Document and Entity Information - USD ($) $ in Millions	12 Months Ended
Document and Entity Information - USD ($) $ in Millions	Dec. 31, 2017	Mar. 09, 2018	Jun. 30, 2017
Document And Entity Information [Abstract]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2017
Document Fiscal Year Focus	2017
Document Fiscal Period Focus	FY
Trading Symbol	APVO
Entity Registrant Name	APTEVO THERAPEUTICS INC.
Entity Central Index Key	0001671584
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	No
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Entity Filer Category	Smaller Reporting Company
Entity Common Stock, Shares Outstanding		21,112,605
Entity Public Float			$ 35.8

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Current assets:
Cash and cash equivalents	$ 7,095	$ 9,676
Short-term investments	73,688	44,849
Accounts receivable	2,141	307
Inventories	1,028	461
Current assets held for sale		10,155
Restricted cash, current portion	400	400
Prepaid expenses	4,022	3,540
Other current assets	6,710	2,026
Total current assets	95,084	71,414
Restricted cash, net of current portion	10,000
Property and equipment, net	5,843	5,910
Intangible assets, net	6,080	6,910
Long-term assets held for sale		7,624
Total assets	117,007	91,858
Current liabilities:
Accounts payable and other accrued liabilities	7,350	10,518
Accrued compensation	4,626	4,009
Deferred revenue, current portion		811
Current portion of long-term debt	3,333
Other short-term liabilities	3,201	278
Current liabilities held for sale		3,928
Total current liabilities	18,510	19,544
Deferred revenue, net of current portion		2,896
Long-term debt, net	15,728	18,383
Other liabilities	734	469
Total liabilities	34,972	41,292
Stockholders' equity:
Preferred stock: $0.001 par value; 15,000,000 shares authorized, zero shares issued or outstanding
Common stock: $0.001 par value; 500,000,000 shares authorized; 21,605,716 and 20,271,737 shares issued and outstanding at December 31, 2017 and December 31, 2016, respectively	22	20
Additional paid-in capital	155,837	151,271
Accumulated other comprehensive loss	(105)	(33)
Contribution receivable from former parent		(20,000)
Accumulated deficit	(73,719)	(80,692)
Total stockholders' equity	82,035	50,566
Total liabilities and stockholders' equity	$ 117,007	$ 91,858

CONSOLIDATED BALANCE SHEETS (Parenthetical) - $ / shares	Dec. 31, 2017	Dec. 31, 2016
Statement Of Financial Position [Abstract]
Preferred stock, par value	$ 0.001	$ 0.001
Preferred stock, shares authorized	15,000,000	15,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value	$ 0.001	$ 0.001
Common stock, shares authorized	500,000,000	500,000,000
Common stock, shares issued	21,605,716	20,271,737
Common stock, shares outstanding	21,605,716	20,271,737

CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Revenues:
Product sales	$ 10,949	$ 9,805
Collaborations	3,709	180
Total revenues	14,658	9,985
Costs and expenses:
Cost of product sales	5,010	12,467
Research and development	29,021	29,120
Selling, general and administrative	34,576	36,158
Impairment of goodwill and intangible assets		71,013
Loss from operations	(53,949)	(138,773)
Other expense:
Other expense	(1,944)	(810)
Total other expense	(1,944)	(810)
Loss before income taxes	(55,893)	(139,583)
Benefit from income taxes	23,301	19,692
Net loss from continuing operations	(32,592)	(119,891)
Discontinued operations (Note 2):
Income from discontinued operations, before income taxes	62,864	11,828
Income tax expense	(23,299)	(4,352)
Income from discontinued operations	39,565	7,476
Net income (loss)	$ 6,973	$ (112,415)
Basic and diluted net income (loss) per share:
Net loss from continuing operations	$ (1.53)	$ (5.92)
Net income from discontinued operations	1.86	0.37
Net income (loss)	$ 0.33	$ (5.55)
Weighted-average shares used to compute per share calculation	21,335,157	20,239,160

CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Statement Of Income And Comprehensive Income [Abstract]
Net income (loss)	$ 6,973	$ (112,415)
Other comprehensive loss:
Unrealized losses on available-for-sale investments, net	(72)	(33)
Total comprehensive income (loss)	$ 6,901	$ (112,448)

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Operating Activities
Net income (loss)	$ 6,973	$ (112,415)
Adjustments to reconcile net income (loss) to net cash used in operating activities:
Stock-based compensation	4,884	3,809
Depreciation and amortization	3,127	3,362
Gain on sale of Hyperimmune Business	(52,697)
Impairment of goodwill and intangible assets		71,013
Non-cash interest expense	925
Other	(287)
Income taxes	(2)	(15,817)
Change in fair value of contingent consideration		(444)
Changes in operating assets and liabilities:
Accounts receivable	(1,834)	2,172
Inventories	(567)	13,683
Income taxes		1,376
Prepaid expenses and other current assets	(1,628)	(3,223)
Accounts payable, accrued compensation and other liabilities	195	2,479
Change in assets and liabilities held for sale	2,700
Restricted cash		(400)
Sales rebates and discounts	345	997
Deferred revenue	(3,707)	(3,454)
Net cash used in operating activities	(41,573)	(36,862)
Investing Activities
Proceeds from the maturity of investments	70,730
Cash proceeds from sale of Hyperimmune Business	59,763
Purchases of property and equipment	(1,402)	(2,512)
Purchases of investments	(99,633)	(44,882)
Net cash provided by (used in) investing activities	29,458	(47,394)
Financing Activities
Transfer from former parent, prior to spin-off		71,219
Settlement of contribution receivable from former parent	20,000
Proceeds from long-term debt, net of issuance costs (and modification fees)	(150)	18,038
Common stock issued upon exercise of stock options	442	38
Value of equity awards withheld for tax liability	(758)
Restricted cash related to loan agreement	(10,000)
Net cash provided by financing activities	9,534	89,295
(Decrease) increase in cash and cash equivalents	(2,581)	5,039
Cash and cash equivalents at beginning of period	9,676	4,637
Cash and cash equivalents at end of period	7,095	9,676
Supplemental disclosures:
Contribution receivable from former parent		20,000
Cash paid for interest	1,778	537
Cash paid for taxes	$ 1,359	$ 162

CONSOLIDATED STATEMENT OF CHANGES IN STOCKHOLDERS EQUITY - USD ($) $ in Thousands	Total	Common Stock	Former Parent Investment in Subsidiary	Additional Paid-In Capital	Accumulated Deficit	Contribution Receivable from Former Parent	Accumulated Other Comprehensive Loss
Balance at Dec. 31, 2015	$ 88,618		$ 320,606		$ (231,988)
Capitalization upon spinoff	20	$ 20
Capitalization upon spinoff (in shares)		20,229,849
Transfers from former parent	70,529		(288,883)	$ 147,424	231,988	$ (20,000)
Unrealized losses on available- for-sale investments	(33)						$ (33)
Common stock issued upon exercise of stock options	20			20
Common stock issued upon exercise of stock options (in shares)		9,144
Common stock issued upon vesting of restricted stock units	18			18
Common stock issued upon vesting of restricted stock units (in shares)		32,744
Stock-based compensation	3,809			3,809
Net income (loss) for the period	(112,415)		$ (31,723)		(80,692)
Balance at Dec. 31, 2016	50,566	$ 20		151,271	(80,692)	(20,000)	(33)
Balance (in shares) at Dec. 31, 2016		20,271,737
Transfers from former parent	20,000					$ 20,000
Unrealized losses on available- for-sale investments	(72)						(72)
Common stock issued upon exercise of stock options	440			440
Common stock issued upon exercise of stock options (in shares)		174,763
Common stock issued upon vesting of restricted stock units	(756)	$ 2		(758)
Common stock issued upon vesting of restricted stock units (in shares)		1,159,216
Stock-based compensation	4,884			4,884
Net income (loss) for the period	6,973				6,973
Balance at Dec. 31, 2017	$ 82,035	$ 22		$ 155,837	$ (73,719)		$ (105)
Balance (in shares) at Dec. 31, 2017		21,605,716

Nature of Business and Significant Accounting Policies

12 Months Ended

Dec. 31, 2017

Accounting Policies [Abstract]

Nature of Business and Significant Accounting Policies

Note 1. Nature of Business and Significant Accounting Policies

Organization and Basis of Presentation

Aptevo Therapeutics Inc. (Aptevo, we, us, or the Company) is a biotechnology company focused on novel oncology (cancer) and hematology (blood disease) therapeutics to meaningfully improve patients’ lives. Our core technology is the ADAPTIR (modular protein technology) platform. We currently have one revenue-generating product in the area of hematology, IXINITY, as well as various investigational stage product candidates in the area of immuno-oncology and autoimmune and inflammatory diseases.

The accompanying financial statements have been prepared in accordance with U.S. generally accepted accounting principles (GAAP). These consolidated financial statements include all adjustments, which include normal recurring adjustments, necessary for the fair presentation of the Company’s financial position.

On August 6, 2015, Emergent BioSolutions Inc., (Emergent or former parent), announced a plan to separate into two independent publicly traded companies. To accomplish this separation, Emergent created Aptevo Therapeutics Inc. or Aptevo, to be the parent company for the development-based biotechnology business focused on novel oncology and hematology therapeutics. Aptevo was incorporated in Delaware in February 2016 as a wholly owned subsidiary of Emergent. To effect the separation, Emergent made a pro rata distribution of Aptevo’s common stock to Emergent’s stockholders on August 1, 2016. We are currently trading on the NASDAQ Global Market under the symbol “APVO.”

Prior to August 1, 2016, the consolidated financial statements were prepared on a “carve-out” basis for the purpose of presenting Aptevo’s financial position, results of operations, and cash flows, and were derived from Emergent’s consolidated financial statements and accounting records. Aptevo did not operate as a standalone entity in the past and accordingly the selected financial data presented herein is not necessarily indicative of Aptevo’s future performance and does not reflect what Aptevo’s performance would have been had Aptevo operated as an independent publicly-traded company prior to August 1, 2016. The consolidated financial statements reflect Aptevo’s financial position, results of operations, and cash flows as a separately operated business in conformity with GAAP post the August 1, 2016 spin-off.

Prior to August 1, 2016, the consolidated financial statements included an allocation of certain assets and liabilities that have historically been held at the Emergent corporate level but which were specifically identifiable or allocable to Aptevo. All Aptevo intracompany transactions and accounts have been eliminated. All intercompany transactions between Aptevo and Emergent are considered to be effectively settled in the consolidated financial statements at the time the transaction was recorded. The total net effect of the settlement of these intercompany transactions is reflected in the consolidated statement of cash flows as a financing activity and in the consolidated balance sheet as a net investment from Emergent. As of August 1, 2016, in connection with the separation and distribution, Emergent’s investment in the Company’s business was redesignated as stockholder’s equity and allocated between common stock and additional paid-in capital based on the number of shares issued at the distribution date.

Prior to August 1, 2016, Aptevo’s consolidated financial statements included an allocation of expenses related to certain Emergent corporate functions, including senior management, legal, human resources, finance, information technology, and quality assurance. These expenses were allocated to Aptevo based on direct usage or benefit where identifiable, with the remainder allocated on a pro rata basis of expenses, headcount, square footage, or other measures. Aptevo considers the expense allocation methodology and results to be reasonable for all periods presented. However, the allocations may not be indicative of the actual expense that would have been incurred had Aptevo operated as an independent, publicly-traded company for the periods presented.

Prior to August 1, 2016, the income tax amounts in these consolidated financial statements were calculated based on a separate return methodology and presented as if Aptevo’s operations were a standalone taxpayer in each of its tax jurisdictions.

On September 28, 2017, Aptevo completed the sale of its hyperimmune business which consisted of the following products: WinRho^® SDF for autoimmune platelet disorder and hemolytic disease of the newborn; HepaGam B^® for the prevention of Hepatitis B following liver transplantation and for treatment following hepatitis B exposure; and VARIZIG^® for treatment following exposure to varicella zoster virus for individuals with compromised immune systems (Hyperimmune Business). The Hyperimmune Business met all the conditions to be classified as a discontinued operation since the sale of Hyperimmune Business represented a strategic shift that will have a major effect on the Company’s operations and financial results. Aptevo will not have further significant involvement in the operations of the discontinued Hyperimmune Business. The operating results of the Hyperimmune Business are reported as income from the discontinued operations, both pre-tax and net of tax, in the consolidated statements of operations for all periods presented. The gain recognized on the sale of the Hyperimmune Business is presented in income (loss) from discontinued operations, both pre-tax and net of tax, in the consolidated statement of operations. In addition, on the consolidated balance sheet as of December 31, 2016, the assets and liabilities held for sale have been presented separately. See Note 2 - Sale of Hyperimmune Business for additional information.

Significant Accounting Policies

Use of Estimates

The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from these estimates.

Principles of Consolidation

The consolidated financial statements include the accounts of the company and its wholly owned subsidiaries: Aptevo Research and Development LLC; Aptevo BioTherapeutics LLC; and Aptevo Europe Limited. All intercompany balances and transactions have been eliminated.

Cash Equivalents

Cash equivalents are highly liquid investments with a maturity of 90 days or less at the date of purchase and include time deposits and investments in money market funds with commercial banks and financial institutions.

Restricted Cash

We have restricted cash in the amount of $10.4 million of which $10.0 million relates to a covenant of our MidCap loan agreement, and $0.4 million is maintained in depository as collateral for corporate credit cards.

Short-Term Investments

Short-term investments are classified as available-for-sale and are carried at fair value. Unrealized gains and losses, if any, are reported as a component of comprehensive loss. Amortization, accretion, interest and dividends, realized gains and losses and declines in value judged to be other-than-temporary are included in other income (expense). The cost of securities sold is based on the specific-identification method. Investments in securities with maturities of less than one year, or those for which management intends to use the investments to fund current operations, are included in current assets. We evaluate whether an investment is other-than-temporarily impaired based on the specific facts and circumstances. Factors that are considered in determining whether an other-than-temporary decline in value has occurred include: the market value of the security in relation to its cost basis; the financial condition of the investee; and the intent and ability to retain the investment for a sufficient period of time to allow for recovery in the market value of the investment.

Concentrations of Credit Risk

Financial instruments that potentially subject Aptevo to concentrations of credit risk consist primarily of cash and cash equivalents, certain investments and accounts receivable. Aptevo places its cash and cash equivalents with high quality financial institutions and may maintain cash balances in excess of insured limits. Management believes that the financial risks associated with its cash and cash equivalents are minimal.

Accounts Receivable

Aptevo records accounts receivable net of an allowance for doubtful accounts based upon its assessment of collectability, and of applicable discounts. Aptevo performs ongoing credit evaluations of its customers and generally does not require collateral. As a result of its sale of its Hyperimmune Business in September 2017, accounts receivable net of an allowance for doubtful accounts has been revised to reflect the removal of its allowance for doubtful accounts, as the prior balance solely related to the Hyperimmune Business. See Note 2, Sale of Hyperimmune Business for additional information on the divestiture.

Inventories

Inventories, including purchased inventories, are stated at the lower of cost or market with cost being determined using a moving average cost method, which approximates weighted-average cost. Average cost consists primarily of material, labor and manufacturing overhead expenses (including allocation of fixed production-overhead costs) and includes the services and products of third-party suppliers. Aptevo analyzes its inventory levels quarterly and writes down, in the applicable period, inventory that has become obsolete, inventory that has a cost basis in excess of its expected net realizable value and inventory in excess of expected customer demand. Aptevo also writes off, in the applicable period, the costs related to expired inventory and unsuccessful manufacturing runs.

Property and Equipment

Property and equipment are stated at cost. Depreciation is computed using the straight-line method over the following estimated useful lives:

Furniture and equipment	7-10 years
Software and hardware	3-5 years or product life
Leasehold improvements	Lesser of the asset life or the remaining lease term

Upon retirement or sale, the cost of assets disposed of and the related accumulated depreciation are removed from the accounts and any resulting gain or loss is credited or charged to operations. Repairs and maintenance costs are expensed as incurred.

Fair Value of Financial Instruments

We measure and record cash equivalents and investment securities considered available-for-sale at fair value in the accompanying financial statements. Fair value is defined as the exchange price that would be received for an asset or paid to transfer a liability, an exit price, in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. Valuation techniques used to measure fair value must maximize the use of observable inputs and minimize the use of unobservable inputs.

The carrying amounts of our short-term financial instruments, which include cash and cash equivalents, accounts receivable and accounts payable, approximate their fair value due to their short maturities.

Product Sales, Rebates and other Discounts

Aptevo markets and sells its product through commercial wholesalers (direct customers) who purchase the product at a price referred to as the wholesale acquisition cost (WAC). Additionally, Aptevo may enter into separate agreements with indirect customers to acquire its product for a contracted price that is less than the product’s WAC. The indirect customers, such as group-purchasing organizations, physician practice-management groups and hospitals, continue to purchase Aptevo’s product from the wholesalers, but at their respective contractual prices. Per its wholesaler agreements, Aptevo guarantees to credit the wholesaler for the difference between the WAC and the indirect customers’ contracted price. This credit is referred to as a chargeback and revenues from product sales are recorded net of estimated chargebacks. Adjustments to the chargeback provisions are made periodically to reflect new facts and circumstances, therefore historical experience may not be indicative of current and/or future results.

All revenues from product sales are also recorded net of applicable allowances for sales and government rebates, special promotional programs, and discounts. Management does not believe there to be a legal right of offset related to these allowances and the receivables from wholesalers; accordingly, allowances are classified as a current liability in the accompanying balance sheets. These allowances are estimated based on historical payment experience, historical relationship to revenues, estimated customer inventory levels, contract terms, and actual discounts offered. In arriving at these estimates, Aptevo further utilizes information received from third parties including market data, inventory reports from major wholesalers, historical information and analysis. These estimates are subject to the inherent limitations of estimates that rely on third-party data, as certain third-party information may itself rely on estimates and reflect other limitations.

Debt Issuance Costs

Aptevo defers costs related to debt issuance and amortizes these costs to interest expense over the term of the debt, using the effective interest method. Debt issuance costs are presented in the balance sheet as a reduction of the carrying amount of the debt liability.

Revenue Recognition

Aptevo recognizes revenue if four basic criteria have been met: (1) there is persuasive evidence of an arrangement, (2) delivery has occurred or services have been rendered, (3) the fee is fixed or determinable, and (4) collectability is reasonably assured. Where the revenue recognition criteria are not met, we defer the recognition of revenue by recording deferred revenue until such time as all criteria are met.

Collaborations

Revenue generating collaborative research and development agreements may contain one or more provisions including licensing, research services and milestone deliverables. Aptevo analyzes its multiple element revenue generating arrangements to determine whether the elements can be separated and accounted for individually as separate units of accounting. An item can generally be considered a separate unit of accounting if both of the following criteria are met: (1) the delivered item(s) has value to the customer on a standalone basis, and (2) if the arrangement includes a general right of return and delivery, the performance of the undelivered item(s) is considered probable and substantially in the control of Aptevo. Items that cannot be divided into separate units are consolidated with other units of accounting, as appropriate. Consideration to be received is allocated among the separate units based on each unit’s relative selling price and is then recognized when the appropriate revenue recognition criteria are met. Aptevo deems services to be rendered if no continuing obligation exists on the part of Aptevo.

Revenue associated with non-refundable upfront license fees that can be treated as a single unit of accounting is recognized when all ongoing obligations have been delivered. Revenue associated with non-refundable upfront license fees under arrangements where the license fees and research and development activities cannot be accounted for as separate units of accounting is deferred and recognized as revenue either on a straight-line basis over Aptevo’s continued involvement in the research and development process or based on the proportional performance of Aptevo’s expected future obligations under the contract.

Revenues from the achievement of research and development milestones, if deemed substantive, are recognized as revenue when the milestones are achieved and the milestone payments are due and collectible. Milestones are considered substantive if all of the following conditions are met: (1) the milestone is non-refundable, (2) achievement of the milestone was not reasonably assured at the inception of the arrangement, (3) substantive effort is involved to achieve the milestone and (4) the amount of the milestone payment appears reasonable in relation to the effort expended. If not deemed substantive, Aptevo recognizes such milestone as revenue on a percent of completion basis over the remaining expected term of continued involvement in the research and development process. Payments received in advance of revenue recognized are recorded as deferred revenue.

Research and Development

Research and development costs are expensed as incurred. Research and development costs primarily consist of internal labor costs, fees paid to outside service providers and the costs of materials used in clinical trials and research and development. Other research and development expenses include facility, maintenance and related support expenses.

A substantial portion of Aptevo’s pre-clinical studies and all of its clinical studies have been performed by third-party CROs. The Company reviews the activities performed by the CROs each period. For pre-clinical studies, the significant factors used in estimating accruals include the percentage of work completed to date and contract milestones achieved. For clinical study expenses, the significant factors used in estimating accruals include the number of patients enrolled and services provided but not yet invoiced. The Company’s estimates are highly dependent upon the timeliness and accuracy of the data provided by its CROs regarding the status of each program and total program spending and adjustments are made when deemed necessary.

Selling, General and Administrative Expenses

Selling, general and administrative expenses consist primarily of personnel-related costs and professional fees in support of our executive, sales and marketing, business development, finance, accounting, information technology, legal and human resource functions. Other costs include facility costs not otherwise included in cost of product sales or research and development expense.

Stock-Based Compensation

Under the Financial Accounting Standards Board’s (FASB) ASC 718, Compensation—Stock Compensation, we measure and recognize compensation expense for restricted stock units (RSUs), and stock options granted to our employees and directors based on the fair value of the awards on the date of grant. The fair value of stock options is estimated at the date of grant using the Black-Scholes option pricing model that requires management to apply judgment and make estimates, including:

•

the expected term of the stock option award, which we calculate using the simplified method, as permitted by the SEC Staff Accounting Bulletin No. 110, Share-Based Payment, as we have insufficient historical information regarding our stock options to provide a basis for an estimate;

•

the expected volatility of our underlying common stock, which we estimate based on the historical volatility of a representative group of publicly traded biopharmaceutical companies with similar characteristics to us, and our own historical and implied future volatility;

•

the risk-free interest rate, which we based on the yield curve of U.S. Treasury securities with periods commensurate with the expected term of the options being valued;

•

the expected dividend yield, which we estimate to be zero based on the fact that we have never paid cash dividends and have no present intention to pay cash dividends; and

•

the fair value of our common stock on the date of grant.

Stock-based compensation expense for RSUs is recognized on a straight-line basis over the vesting period of the respective award. Stock-based compensation expense for our stock options, both converted and Aptevo granted, is recognized on a straight-line basis over the vesting period of the respective award.

We are required to estimate a forfeiture rate to calculate the stock-based compensation expense for our awards. Our forfeiture rate for the converted RSUs and options is based on an analysis of the actual forfeitures experienced by Emergent. For the RSUs and options issued by Aptevo, we have estimated a forfeiture rate of ten-percent. Since inception our actual forfeiture rate has been de minimis. We routinely evaluate the appropriateness of the forfeiture rate based on actual forfeiture experience, analysis of employee turnover, and expectations of future option exercise behavior.

Income Taxes

Income taxes are accounted for using the liability method. Deferred tax assets and liabilities are recognized for future tax consequences attributable to differences between financial statement carrying amounts of existing assets and liabilities and their respective tax bases and net operating loss and research and development tax credit carry forwards. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the year in which those temporary differences are expected to be recovered or settled.

Aptevo’s ability to realize deferred tax assets depends upon future taxable income as well as the limitations discussed below. For financial reporting purposes, a deferred tax asset must be reduced by a valuation allowance if it is more likely than not that some portion or all of the deferred tax assets will not be realized prior to expiration. Aptevo considers future taxable income and ongoing tax planning strategies in assessing the need for valuation allowances. In general, if Aptevo determines that it is more likely than not to realize more than the recorded amounts of net deferred tax assets in the future, Aptevo will reverse all or a portion of the valuation allowance established against its deferred tax assets, resulting in a decrease to the provision for income taxes in the period in which the determination is made. Likewise, if Aptevo determines that it is not more likely than not to realize all or part of the net deferred tax asset in the future, Aptevo will establish a valuation allowance against deferred tax assets, with an offsetting increase to the provision for income taxes, in the period in which the determination is made.

Because tax laws are complex and subject to different interpretations, significant judgment is required. As a result, Aptevo makes certain estimates and assumptions, in (1) calculating Aptevo’s income tax expense, deferred tax assets and deferred tax liabilities, (2) determining any valuation allowance recorded against deferred tax assets and (3) evaluating the amount of unrecognized tax benefits, as well as the interest and penalties related to such uncertain tax positions. Aptevo’s estimates and assumptions may differ significantly from tax benefits ultimately realized.

Segment Reporting

We have determined that we operate in a single segment and have one reporting unit: the discovery, development, commercialization and sale of novel oncology and hematology therapeutics.

New Accounting Pronouncements

In May 2014, the Financial Accounting Standards Board (FASB) issued Accounting Standard Update No. 2014-09, Revenue from Contracts with Customers (Topic 606), and has subsequently issued a number of amendments to ASU 2014-09. The new standard as amended, provides a single comprehensive model to be used in the accounting for revenue arising from contracts with customers and supersedes current revenue recognition guidance, included industry-specific guidance. The standard’s stated core principle is that an entity should recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. To achieve this core principle, ASU 2014-09 included provisions within a five-step model that includes identifying the contract with a customer, identifying the performance obligations in the contract, determining the transaction price, allocating the transaction price to the performance obligations, and recognizing revenue, when, or as, an entity satisfies a performance obligation. In addition, the standard requires disclosure of the nature, amount, timing, and uncertainty of revenue and cash flows arising from contracts with customers.

Aptevo adopted this new standard effective January 1, 2018, on a modified retrospective basis, which requires the cumulative effect of the adoption to be recognized as an adjustment to opening retained earnings in the first period of adoption. The adoption of ASU No. 2014-09 did not have a material impact on recorded amounts when applied to the opening balance sheet as of January 1, 2018, and is not expected to impact the amount or timing of the future amounts of net income. Additional impacts could still result when the standard is first applied to revenue transactions during the first quarter of 2018.

In February 2016, the FASB issued ASU No. 2016-02, Leases (Topic 842). Under the new guidance, lessees will be required to recognize a lease liability and a right-of-use asset for all leases (with the exception of short term leases) at the commencement date. Lessor accounting under ASU 2016-02 is largely unchanged. ASU 2016-02 is effective for annual and interim periods beginning on or after December 15, 2018 and early adoption is permitted. Under ASU 2016-02, lessees (for capital and operating leases) and lessors (for sales-type, direct financing, and operating leases) must apply a modified retrospective transition approach for leases existing at, or entered into after, the beginning of the earliest comparative period presented in the financial statements. Lessees and lessors may not apply a full retrospective transition approach. The ASU will be effective for the Company starting on January 1, 2019. Aptevo is continuing to evaluate the impact of the application of this ASU on our consolidated financial statements and disclosures. We expect to recognize right of use assets and lease liabilities.

In March 2016, the FASB issued ASU 2016-09, “Compensation – Stock Compensation (Topic 718): Improvements to Employee Share-Based Payment Accounting.” ASU 2016-09 simplifies the accounting for share-based payment award transactions including the financial statement presentation of excess tax benefits and deficiencies, classification of awards as either equity or liabilities, accounting for forfeitures and classification on the statement of cash flows. Aptevo adopted this standard effective January 1, 2017. Upon adoption of the standard, excess tax benefits and deficiencies resulting from stock-based compensation awards vesting and exercises are now recognized as discrete items in the statement of operations. Aptevo has elected to maintain its current forfeitures policy and will continue to include an estimate of forfeitures when recognizing stock-based compensation expense. Additionally, cash paid by Aptevo when directly withholding shares for tax withholding purposes will continue to be classified as a financing activity in the consolidated statement of cash flows as required by the standard. The adoption of this standard did not have a material impact on Aptevo’s consolidated financial statements and related disclosures.

In August 2016, the FASB issued ASU 2016-15, “Statement of Cash Flows (Topic 230): Classification of Certain Cash Receipts and Cash Payments,” which clarifies the classification and presentation of eight specific cash flow issues in the statement of cash flows. Aptevo adopted this standard effective January 1, 2018. The new standard requires a retrospective transition. Aptevo is aware the adoption of this standard will have an impact for restricted cash, and is evaluating further impacts on its consolidated financial statements.

Sale of Hyperimmune Business

12 Months Ended

Dec. 31, 2017

Discontinued Operations And Disposal Groups [Abstract]

Sale of Hyperimmune Business

Note 2. Sale of Hyperimmune Business

On August 31, 2017, Aptevo entered into a sale agreement with Saol International Limited (Saol) whereby Aptevo agreed to sell its Hyperimmune Business. The sale was completed on September 28, 2017.

At the closing of the sale, Saol paid an amount equal to $65.0 million, including $3.3 million which was deposited in an escrow account for the purposes of satisfying any indemnification claims brought by Saol pursuant to the LLC sale agreement. In addition, Aptevo may receive (1) an additional potential milestone payment totaling up to $7.5 million related to the achievement of certain gross profit milestones and (2) up to $2.0 million related to collection of certain accounts receivable after the closing.

The net gain on sale of the Hyperimmune Business totaling, $52.7 million, was calculated as the difference between the fair value of the consideration received for the Hyperimmune Business, the carrying value of the net assets transferred to Saol, less the transaction costs incurred and a working capital adjustment. The net gain on sale of the business may be adjusted in future periods by the contingent consideration based upon the achievement of certain gross profit milestones and collection of certain outstanding accounts receivable.

The following table summarizes the gain on sale (in thousands):

Cash payment received	$	61,750
Escrow receivable		3,250
Collection of accounts receivable		37
Total consideration		65,037
Less:
Net carrying value of assets transferred to Saol		10,315
Transaction costs		1,273
Working capital adjustment		752
Net gain on sale of business	$	52,697

As a result of Aptevo’s decision to sell the Hyperimmune Business, the consolidated balance sheets for the year ended December 31, 2017, and December 31, 2016, have been revised to reflect the results from the sale of the Hyperimmune Business, and related assets and liabilities, as discontinued operations. The amounts calculated for the discontinued operations include certain allocations that management believes fairly reflect the Hyperimmune Business operations.

The following table presents a reconciliation of the carrying amounts of assets and liabilities of the hyperimmune assets held for sale, net in the consolidated balance sheet (in thousands):

ASSETS	December 31, 2016
Accounts receivable	$	3,977
Inventories		6,178
Total current assets, held for sale		10,155

Intangible assets, net		7,624
Total assets held for sale	$	17,779
LIABILITIES
Accounts payable and other accrued liabilities	$	3,928
Total current liabilities	$	3,928

The following table represents the components attributable to the Hyperimmune Business presented as income from discontinued operations in the consolidated statements of operations (in thousands):

	For the Year Ended December 31,
	2017			2016
Revenues:
Product sales	$	18,886		$	26,449
Total revenues		18,886			26,449
Costs and expenses:
Cost of product sales		7,730			11,715
Research and development		44			398
Selling, general and administrative		945			2,508
Income from operations		10,167			11,828
Gain on sale of Hyperimmune Business		52,697			—
Income from discontinued operations, before income taxes		62,864			11,828
Income tax expense		(23,299	)		(4,352	)
Income from discontinued operations	$	39,565		$	7,476

Amortization for the Hyperimmune Business was $0.8 million and $1.2 million for the year ended December 31, 2017 and December 31, 2016, respectively. There was no depreciation, capital expenditures or other significant operating or investing non-cash items for the year ended December 31, 2017 and 2016.

Collaboration Agreement	12 Months Ended
Collaboration Agreement	Dec. 31, 2017
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Collaboration Agreement	Note 3. Collaboration Agreements Alligator On July 20, 2017, our wholly owned subsidiary Aptevo Research and Development LLC (Aptevo R&D), entered into a collaboration and option agreement (Collaboration Agreement) with Alligator Bioscience AB, (Alligator), pursuant to which Aptevo and Alligator will collaboratively develop ALG.APV-527, a lead bispecific antibody candidate simultaneously targeting 4-1BB (CD137), a member of the TNFR superfamily of a costimulatory receptor found on activated T-cells, and 5T4 a tumor antigen widely overexpressed in a number of different types of cancer. This product candidate is built on our novel ADAPTIR platform, which is designed to expand on the utility and effectiveness of therapeutic antibodies. Under this Collaboration Agreement, Alligator also granted to Aptevo a time-limited option to enter into a second agreement with Alligator for the joint development of a separate bispecific antibody candidate simultaneously targeting 4-1BB (CD137) and 5T4 a tumor antigen that Aptevo R&D and Alligator will collaboratively select. In accordance with the terms of the Collaboration Agreement, the parties intend to develop the lead bispecific antibody candidate targeting 4-1BB (CD137) and 5T4 through the completion of Phase II clinical trials in accordance with an agreed upon development plan and budget. Subject to certain exceptions for Aptevo’s manufacturing and platform technologies, the parties will jointly own intellectual property generated in the performance of the development activities under the Collaboration Agreement. Following the completion of the anticipated development activities under the Collaboration Agreement, the parties intend to seek a third-party commercialization partner for this product candidate, or, in certain circumstances, may elect to enter into a second agreement granting rights to either Aptevo R&D or Alligator to allow such party to continue the development and commercialization of this product candidate. Under the terms of this Collaboration Agreement, the parties intend to share revenue received from a third-party commercialization partner equally, or, if the development costs are not equally shared under this Collaboration Agreement, in proportion to the development costs borne by each party. The Collaboration Agreement also contains several points in development at which either party may elect to “opt-out” (i.e., terminate without cause) and, following a termination notice period, cease paying development costs for this product candidate, which would be borne fully by the continuing party. Following an opt-out by a party, the continuing party will be granted exclusive rights to continue the development and commercialization of the product candidate, subject to a requirement to pay a percentage of revenue received from any future commercialization partner for this product, or, if the continuing party elects to self-commercialize, tiered royalties on the net sales of the product by the continuing party ranging from the low to mid-single digits, based on the point in development at which the ‘opt-out’ occurs. The parties have also agreed on certain technical criteria or ‘stage gates’ related to the development of this product candidate that, if not met, will cause an automatic termination and wind-down of this Collaboration Agreement and the activities thereunder, provided that the parties do not agree to continue. The Collaboration Agreement contains industry standard termination rights, including for material breach following a specified cure period, and in the case of a party’s insolvency. MorphoSys In August 2014, Aptevo entered into a collaboration agreement with MorphoSys AG (MorphoSys Agreement) for the joint development of MOR209/ES414, a targeted immunotherapeutics protein, which activates host T-cell immunity specifically against cancer cells expressing prostate specific membrane antigen, an antigen commonly overexpressed on prostate cancer cells. Effective August 31, 2017, MorphoSys terminated the MorphoSys Agreement. As a result of the termination, Aptevo has no ongoing obligation related to this agreement and therefore recognized the total remaining deferred revenue balance of $3.7 million as collaborations revenue in the third quarter of 2017.

Fair Value Measurements

12 Months Ended

Dec. 31, 2017

Fair Value Disclosures [Abstract]

Fair Value Measurements

Note 4. Fair Value Measurements

The Company’s estimates of fair value for financial assets and financial liabilities are based on the framework established in the fair value accounting guidance. The framework is based on the inputs used in valuation, gives the highest priority to quoted prices in active markets and requires that observable inputs be used in the valuations when available. The disclosure of fair value estimates in the fair value accounting guidance hierarchy is based on whether the significant inputs into the valuation are observable. In determining the level of the hierarchy in which the estimate is disclosed, the highest priority is given to unadjusted quoted prices in active markets and the lowest priority to unobservable inputs that reflect the Company’s significant market assumptions. The level in the fair value hierarchy within which the fair value measurement is reported is based on the lowest level input that is significant to the measurement in its entirety. The three levels of the hierarchy are as follows:

Level 1— Quoted prices in active markets for identical assets and liabilities;

Level 2— Inputs other than quoted prices in active markets that are either directly or indirectly observable; and

Level 3— Unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the assets or liabilities.

The Company’s financial assets measured at fair value consisted of the following as of December 31, 2017 and December 31, 2016:

	December 31, 2017
(in thousands)	Level 1		Level 2		Level 3		Total
Financial Assets:
Money market funds⁽¹⁾	$	10,997	$	—	$	—	$	10,997
Corporate bonds		—		16,443		—		16,443
US government and agency debt securities		—		33,300		—		33,300
Foreign government and agency debt securities		—		23,945		—		23,945
Total assets	$	10,997	$	73,688	$	—	$	84,685

	December 31, 2016
(in thousands)	Level 1		Level 2		Level 3		Total
Financial Assets:
Money market funds	$	5,215	$	—	$	—	$	5,215
Corporate bonds		—		9,951		—		9,951
US government and agency debt securities		—		34,898		—		34,898
Foreign government and agency debt securities		—		—		—		—
Total assets	$	5,215	$	44,849	$	—	$	50,064
⁽¹⁾ As of December 31, 2017, the money market funds included $10.0 million in restricted cash.

If quoted market prices in active markets for identical assets are not available to determine fair value, then the Company uses quoted prices of similar instruments and other significant inputs derived from observable market data obtained from third-party data providers. These investments are included in Level 2 and consist of debt securities of U.S government agencies and corporate bonds. There were no transfers between Levels 1 and 2 during the twelve-month period ended December 31, 2017.

- Definition

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

+ References + Details

Investments

12 Months Ended

Dec. 31, 2017

Investments Debt And Equity Securities [Abstract]

Investments

Note 5. Investments

Investments are classified as available-for-sale securities and are carried at fair value with unrealized temporary holding gains and losses included in other comprehensive income or loss and as a net amount in accumulated other comprehensive income or loss until such gains and losses are realized. We did not recognize any realized gains or losses in net income during 2017. Available-for-sale securities are written down to fair value through income whenever it is necessary to reflect other than temporary impairments. We have determined that the unrealized gains on our marketable securities as of December 31, 2017 were temporary in nature, and currently does not intend to sell these securities before recovery of their amortized cost basis. All short-term investments are limited to a final maturity of less than one year from the reporting date.

	December 31, 2017
(in thousands)	Amortized Cost		Gross Unrealized Holding Gains		Gross Unrealized Holding (Losses)			Fair Value
Cash equivalents:
Money market funds⁽¹⁾	$	10,997	$	—	$	—		$	10,997
Total cash equivalents	$	10,997	$	—	$	—		$	10,997

Short-term investments:
Corporate bonds	$	16,455	$	—	$	(12	)	$	16,443
US government and agency debt securities		33,331		—		(31	)		33,300
Foreign government and agency debt securities		24,007		—		(62	)		23,945
Total short-term investments	$	73,793	$	—	$	(105	)	$	73,688

	December 31, 2016
(in thousands)	Amortized Cost		Gross Unrealized Holding Gains		Gross Unrealized Holding (Losses)			Fair Value
Cash equivalents:
Money market fund	$	5,215	$	—	$	—		$	5,215
Total cash equivalents	$	5,215	$	—	$	—		$	5,215

Short-term investments:
Corporate bonds	$	9,959	$	1	$	(9	)	$	9,951
US government and agency debt securities		34,923		—		(25	)		34,898
Foreign government and ageny debt securities		—		—		—			—
Total short-term investments	$	44,882	$	1	$	(34	)	$	44,849
⁽¹⁾ As of December 31, 2017, the money market funds included $10.0 million in restricted cash.

Inventories

12 Months Ended

Dec. 31, 2017

Inventory Disclosure [Abstract]

Inventories

Note 6. Inventories

Inventories consist of the following:

	December 31,		December 31,
(in thousands)	2017		2016
Raw materials and supplies	$	56	$	260
Work-in-process		482		4
Finished goods		490		197
Total inventories	$	1,028	$	461

Due to the challenges with the manufacture of our IXINITY product that meets release specifications for the final drug product, we wrote off unsaleable IXINITY inventory that was in the process of being manufactured in the amount of $7.1 million in 2016. This cost is included in cost of product sales.

Property and Equipment, Net

12 Months Ended

Dec. 31, 2017

Property Plant And Equipment [Abstract]

Property and Equipment, Net

Note 7. Property and equipment, net

Property, plant and equipment consist of the following:

	December 31,			December 31,
(in thousands)	2017			2016
Leasehold improvements	$	2,228		$	2,265
Furniture and equipment		11,139			10,283
Property and equipment, gross		13,367			12,548
Less: Accumulated depreciation		(7,524	)		(6,638	)
Total property and equipment, net	$	5,843		$	5,910

Depreciation expense for the year ended December 31, 2017 and December 31, 2016 was $1.5 million and $1.1 million, respectively.

Intangible Assets, Net

12 Months Ended

Dec. 31, 2017

Intangible Assets Net Excluding Goodwill [Abstract]

Intangible Assets, Net

Note 8. Intangible Assets, Net

Intangible assets, net, is solely related to our IXINITY product. For the years ended December 31, 2017 and 2016, the Company recorded $0.8 million and $0.8 million, respectively, of intangible asset amortization expense. As of December 31, 2017, the weighted average amortization period remaining for intangible assets was 88 months.

Future amortization expense as of December 31, 2017 is as follows:

(in thousands)
2018	$	830
2019		830
2020		830
2021		830
2022 and beyond		2,760
Total remaining amortization	$	6,080

Debt

12 Months Ended

Dec. 31, 2017

Debt Disclosure [Abstract]

Debt

Note 9. Debt

Credit Facility

On August 4, 2016, we entered into a $35.0 million Credit and Security Agreement (the Credit Agreement) with MidCap Financial Trust. The Credit Agreement, prior to the amendments described below, provided us with up to $35.0 million of available borrowing capacity, available (subject to certain conditions) in two tranches of $20.0 million and $15.0 million. Amounts drawn under the Credit Agreement bear interest at a rate of LIBOR plus 7.60% per annum. The first tranche of $20.0 million was funded on the closing date of the Credit Agreement with the second tranche of $15.0 million to become available (subject to certain conditions) following the date Aptevo and its subsidiaries: (1) achieve net commercial product revenue of $40.0 million on a trailing twelve-month basis, and (2) receive an additional $20.0 million in cash from Emergent. Emergent made this payment on January 13, 2017. We paid debt issuance costs to third-parties and the lender of $1.9 million of which $1.4 million remains unamortized at December 31, 2017. The loan repayment included interest (no principal) through August 2018 and was set to transition to principal and interest as of August 2018 and to be repaid in full on February 1, 2021 (54 months). Amounts drawn under the Credit Agreement bear interest at a rate of LIBOR plus 7.60% per annum.

The Credit Agreement contained financial covenants that require us and our subsidiaries to maintain increasing minimum net commercial product revenue for each twelve-month period ending on the last day of each calendar quarter, commencing with the twelve-month period ending September 30, 2016. As of March 31, 2017, the Company’s net minimum revenue did not meet the required minimum for the twelve months ended March 31, 2017.

As a result, on May 11, 2017, we and MidCap Financial Trust entered into an amendment to the Credit Agreement to, among other things, waive the existing event of default and revise the financial covenants pertaining to the minimum required commercial product revenue for the twelve months ended March 31, 2017 and future rolling twelve-month periods. As a result of the amendment, the Company was in compliance with the modified minimum net revenue covenant for the three and six months ended June 30, 2017. As such, amounts owed under the Credit Facility are classified based on their contractual maturities.

This first amendment revised the provisions of the Credit Agreement to: (1) extend the time period through which the Company could draw the second tranche from August 2017 to March 2018, (2) increase the exit fee of 5.75% of the aggregate principal amount under the Credit Agreement for repayment or prepayment other than scheduled amortization payments and the final payment of principal to 6.75% and (3) permit MidCap Financial Trust to obtain an affirmative lien on the intellectual property of the Company, upon the earlier of (i) the Company’s draw down of the second tranche or (ii) the Company’s cash, cash equivalents, and short-term investments balance descend below a minimum cash threshold of $25 million.

On September 28, 2017, the Company entered into a second amendment of the Credit Agreement (Amendment No. 2) in order to permit the sale under the LLC purchase agreement described in Note 2 Sale of Hyperimmune Business, and to reflect changes in the remaining business as a result of such sale.

In addition, as part of the Amendment No. 2, the agent and the lenders agreed that: (i) the commitments of the lenders to make the remaining $15 million tranche of loans under the credit agreement were terminated, (ii) the covenant levels set forth in the minimum net commercial product revenue covenant were revised, (iii) a new covenant was added requiring the Company to maintain a minimum $10.0 million unrestricted cash balance, and (iv) the date on which the term loans begin to amortize will be extended to February 1, 2019 if the Company achieves net commercial product revenues of $16 million for the twelve month period ending June 30, 2018 and maintains such level of net commercial product revenues for each quarter prior to February 1, 2019 thereafter.

Future principal and interest payments in connection with the Credit Agreement as of December 31, 2017 are as follows:

(in thousands)
2018	$	5,050
2019		9,147
2020		8,441
2021		2,022
Total principal and interest payments	$	24,660

Net Loss Per Share

12 Months Ended

Dec. 31, 2017

Earnings Per Share [Abstract]

Net Income (Loss) Per Share

Note 10. Net Income (Loss) per Share

Basic net income (loss) per share is calculated by dividing the net income (loss) by the weighted average number of common shares outstanding for the period. Diluted net income (loss) per share is computed by dividing the net income (loss) by the weighted average number of common share equivalents outstanding for the period using the as-if converted method. For the purpose of this calculation, stock options and restricted stock units are only included in the calculation of diluted net income per share when their effect is dilutive.

We utilize the control number concept in the computation of diluted earnings per share to determine whether potential common stock instruments are dilutive. The control number used is loss from continuing operations. The control number concept requires that the same number of potentially dilutive securities applied in computing diluted earnings per share from continuing operations be applied to all other categories of income or loss, regardless of their anti-dilutive effect on such categories. Therefore, no dilutive effect has been recognized in the calculation of income from discontinued operations per share.

Prior to the spin-off, Aptevo did not operate as a separate entity and as a result did not have any common stock outstanding other than 1,000 shares held by Emergent. The calculation of basic and diluted net loss per share assumes that the 20,229,849 ordinary shares issued to Aptevo stockholders in connection with the spin-off were outstanding from the beginning of the periods presented.

Common stock equivalents include stock options and unvested RSUs.

The following table presents the computation of basic and diluted net income (loss) per share (in thousands, except share and per share amounts):

	For the Year Ended December 31,
	2017			2016
Net income (loss)	$	6,973		$	(112,415	)

Basic and diluted net income (loss) per share:
Net loss from continuing operations	$	(1.53	)	$	(5.92	)
Net income from discontinued operations	$	1.86		$	0.37
Net income (loss)	$	0.33		$	(5.55	)
Weighted-average shares used to compute per share calculation		21,335,157			20,239,160

The following table represents all potentially dilutive shares, which were all anti-dilutive and therefore excluded from the calculation of diluted net loss per share:

	For the Year Ended December 31,
(in thousands, except for per share amounts)	2017		2016
Outstanding options to purchase common stock		2,819		2,069
Unvested RSUs		1,211		3,034

Equity

12 Months Ended

Dec. 31, 2017

Equity [Abstract]

Equity

Note 11. Equity

Capitalization Upon Spin-off

Converted Equity Awards Incentive Plan

We had no stock-based compensation plans of our own prior to the spin-off from Emergent; however certain Aptevo employees participated in Emergent’s stock-based compensation plans (Emergent Plans), which provided for the grants of stock options and restricted stock units (RSUs). The expense associated with Aptevo employees who participated in the Emergent Plans was allocated to the Company in the accompanying Statements of Operations for the associated periods prior to the spin off.

In connection with the spin-off we adopted the Converted Equity Awards Incentive Plan (Converted Plan) and outstanding equity awards of Emergent held by Aptevo employees were converted into or replaced with equity awards of Aptevo (Conversion Awards) under the Converted Plan and were adjusted to maintain the economic value before and after the distribution date using the relative fair market value of the Emergent and Aptevo common stock based on the closing prices as of August 1, 2016. There was no significant incremental stock-based compensation expense recorded as a result of the equity award conversion. A total of 1.3 million shares of Aptevo common stock have been authorized for issuance under the Converted Plan. Options issued as Conversion Awards were priced according to the Converted Plan. RSUs issued as part of the Converted Plan provide for the issuance of a share of Aptevo’s stock at no cost to the holder.

2016 Stock Incentive Plan

On August 1, 2016, the Company adopted the 2016 Stock Incentive Plan (2016 SIP). A total of 3.1 million shares of Aptevo common stock have been authorized for issuance under the 2016 SIP in the form of incentive stock options.

Stock-Based Compensation Expense

Stock-based compensation expense includes amortization of stock options and restricted stock units granted to employees and non-employees and has been reported in our Consolidated Statements of Operation and Comprehensive Loss as follows:

	For the Year Ended December 31,
(in thousands)	2017		2016
Research and development	$	2,256	$	2,693
Selling, general and administrative		2,628		1,116
Total stock-based compensation expense	$	4,884	$	3,809

The Company accounts for stock-based compensation by measuring the cost of employee services received in exchange for all equity awards granted based on the fair value of the award as of the grant date. The Company recognizes the compensation expense over the vesting period.

Stock Options

Aptevo utilizes the Black-Scholes valuation model for estimating the fair value of all stock options granted. Set forth below are the assumptions used in valuing the stock options granted:

	For the Year Ended December 31,
	2017	2016
Expected dividend yield	0.00%	0.00%
Expected volatility	75.00%	75.00%
Risk-free interest rate	1.90%	1.00%
Expected average life of options	6 years	3 years

Management applied an estimated forfeiture rate for the 2017 plan period of 10%.

The following is a summary of option activity for the year ended December 31, 2017:

	Number of Shares			Weighted- Average Exercise Price		Weighted- Average Remaining Term		Aggregate Intrinsic Value
Balance at December 31, 2016		2,085,214		$	2.57			$	164,767
Granted		1,071,189			2.11				—
Exercised		(204,275	)		4.15				334,268
Forfeited		(132,784	)		2.31				45,557
Outstanding at December 31, 2017		2,819,344		$	2.41		6.92	$	5,156,881
Exercisable at December 31, 2017		1,089,510		$	2.45		4.53	$	1,976,638

As of December 31, 2017, we had $1.6 million of unrecognized compensation expense related to options expected to vest over a weighted average period of 2.0 years. The weighted average remaining contractual life of outstanding and exercisable options is 6.8 years.

The aggregate intrinsic value in the table above represents the total pretax intrinsic value (the difference between the closing stock price of Aptevo’s common stock on the last trading day of 2017 and the exercise price, multiplied by the number of in the money options) that would have been received by the option holders had all the option holders exercised their options on December 31, 2017.

Restricted Stock Units

The following is a summary of restricted stock activity for the year ended December 31, 2017:

	Number of Units			Weighted Average Fair Value per Unit		Aggregate Fair Value
Balance at December 31, 2016		3,034,195		$	2.88	$	7,406,256
Granted		19,803			2.00		37,118
Vested		(1,558,642	)		2.84		2,973,951
Forfeited		(283,869	)		2.94		597,483
Outstanding at December 31, 2017		1,211,487		$	2.91	$	5,136,705
Expected to Vest		1,174,656		$	2.91	$	4,980,541

As of December 31, 2017, we had $0.7 million of unrecognized compensation expense related to RSU’s expected to vest over a period of 0.8 years. The weighted average remaining contractual life of unvested RSU’s is 2.3 years.

The fair value of each RSU has been determined to be the closing trading price of the Company’s common shares on the date of grant as quoted in NASDAQ Global Market.

Leases and Contingencies

12 Months Ended

Dec. 31, 2017

Leases [Abstract]

Leases and Contingencies

Note 13. Leases and Contingencies

The Company leases laboratory and office facilities, and office equipment under operating lease agreements. The Company recognizes rent expense under such arrangements on a straight-line basis over the term of the lease. During the year ended December 31, 2017 and December 31, 2016 total lease expense was $1.7 million and $1.8 million, respectively.

As of December 31, 2017, we are committed to future minimum lease payments under operating lease agreements as follows:

(in thousands)
2018	$	1,713
2019		1,611
2020		543
Total	$	3,867

Income Taxes

12 Months Ended

Dec. 31, 2017

Income Tax Disclosure [Abstract]

Income Taxes

Note 14. Income Taxes

During the periods prior to spin-off, the Company did not file separate tax returns as it was included in the tax returns of Emergent entities within the respective tax jurisdictions. For periods during which our operations were included with Emergent, income taxes are presented in these financial statements as if we filed our own tax returns on a standalone basis. All tax amounts shown in the tables below are presented on a consolidated basis, including both continuing operations and discontinued operations.

On December 22, 2017 the President of the United State signed into law Public Law No. 115-97, commonly referred to as the Tax Cuts and Jobs Act (the Tax Act), following its passage by the United States Congress. The Tax Act will make significant changes to U.S. federal income tax laws, including reduction of the corporate tax rate from 35.0% to 21.0%, limitation of the deduction for net operating losses to 80.0% of current year taxable income and elimination of net operating loss carrybacks, one-time taxation of offshore earning at reduced rates regardless of whether they are repatriated, elimination of U.S. tax on foreign earnings (subject to certain important exceptions), immediate deductions for certain new investments instead of deductions for depreciation expense over time, and modifying or repealing many business deductions. We have estimated the provision for income taxes in accordance with the Tax Act and guidance available to us as of the date of this filing. The provisional amount related to the re-measurement of certain deferred tax assets and liabilities, based on the rates at which they are expected to reverse in the future, was $10.0 million, which is entirely offset by a valuation allowance resulting in zero total tax expense in the period in which the legislation was enacted. The provisional amount related to the one-time transition tax on the mandatory deemed repatriation of foreign earnings was $0.02 million based on cumulative foreign earnings of $0.06 million.

On December 22, 2017, Staff Accounting Bulletin No. 118, or SAB 118, was issued to address the application of GAAP in situations when a registrant does not have the necessary information available, prepared, or analyzed (including computations) in reasonable detail to complete the accounting for certain income tax effects of the Tax Act. Additional work is necessary for a more detailed analysis of the deferred tax assets and liabilities and our historical foreign earnings as well as potential correlative adjustments. Any subsequent adjustment to these amounts will be recorded to current tax expense within the measurement period.

Significant components of the benefits for income taxes attributable to continuing operations consist of the following:

	Year ended December 31,
(in thousands)	2017		2016
Current
Federal	$	12,051	$	4,255
State		710		218
International		2		29
Total current		12,763		4,502
Deferred
Federal		9,636		14,518
State		902		672
International		—		—
Total deferred		10,538		15,190
Total income tax benefit from continuing operations	$	23,301	$	19,692

The table above excludes income tax expense from discontinued operations of $23.3 million and $4.4 million for 2017 and 2016, respectively.

Loss from continuing operations before income taxes is comprised of:

	Year ended December 31,
(in thousands)	2017			2016
US	$	(55,885	)	$	(139,578	)
International		(8	)		(5	)
Loss from continuing operations before benefit from income taxes	$	(55,893	)	$	(139,583	)

The tax effects of temporary differences that give rise to significant portions of the deferred tax assets and deferred tax liabilities are presented below:

	December 31,
(in thousands)	2017			2016
Federal losses carryforward	$	8,454		$	7,237
Intangible assets		4,470			17,464
Stock compensation		1,128			1,726
State losses carryforward		1,246			371
Other		1,262			3,050
Other tax credits		502			384
Fixed assets		309			160
Deferred tax asset		17,371			30,392
Prepaid expenses		(224	)		(575	)
Deferred tax liability		(224	)		(575	)
Valuation allowance		(17,147	)		(29,817	)
Net deferred tax liabilities	$	—		$	—

The table above includes deferred tax assets from discontinued operations of $0 and $10.4 million for 2017 and 2016, respectively.

As of December 31, 2017 and 2016, we have recorded federal net operating losses (NOL) carryforwards of approximately $41.5 and $20.7 million, respectively, state NOL carryforwards of approximately $20.2 million and $9.0, respectively, and tax credit carryforwards of $0.5 million and $0.4 million, respectively, all of which are attributable to continuing operations. The federal losses and credits would begin to expire in 2037. The state net operating losses will begin to expire in varying periods. Carryforwards of net operating losses and tax credits are subject to possible limitation, should a change in ownership occur, as defined by Internal Revenue Code Section 382.

The Company files income tax returns in the U.S. and several state jurisdictions. The 2017 and 2016 tax filings are open to review by taxing authorities.

We are subject to the accounting guidance for uncertain income tax positions. We believe that our income tax positions and deductions will be sustained on audit and do not anticipate any adjustments that will result in a material adverse effect on our financial condition, results of operations, or cash flow. Our policy for recording interest and penalties associated with audits and uncertain tax positions is to record such items as a component of income tax expense, and amounts recognized to date are insignificant. No uncertain income tax positions were recorded during 2017 or 2016, and we do not expect our uncertain tax position to change during the next twelve months.

The reconciliation of the federal statutory income tax rate to the Company’s effective income tax from continuing operations is as follows:

	Year ended December 31,
	2017			2016
Federal tax at statutory rates		35.0	%		35.0	%
State taxes, net of federal benefit		2.4	%		1.0	%
Change in valuation allowance		22.7	%		-6.8	%
Tax credits		0.6	%		0.3	%
Permanent differences		-0.3	%		-7.4	%
Separation related adjustment		—			-7.9	%
Other		-1.3	%		-0.1	%
Tax Reform		-17.4	%		—
Total income tax benefit		41.7	%		14.1	%

Nature of Business and Significant Accounting Policies (Policies)

12 Months Ended

Dec. 31, 2017

Accounting Policies [Abstract]

Use of Estimates

Principles of Consolidation

Cash Equivalents

Restricted Cash

Short-Term Investments

Concentrations of Credit Risk

Accounts Receivable

Inventories

Property and Equipment

Property and equipment are stated at cost. Depreciation is computed using the straight-line method over the following estimated useful lives:

Furniture and equipment	7-10 years
Software and hardware	3-5 years or product life
Leasehold improvements	Lesser of the asset life or the remaining lease term

Fair Value of Financial Instruments

Product Sales, Rebates and other Discounts

Debt Issuance Costs

Revenue Recognition

Collaborations

Research and Development

Selling, General and Administrative Expenses

Stock-Based Compensation

•

the risk-free interest rate, which we based on the yield curve of U.S. Treasury securities with periods commensurate with the expected term of the options being valued;

•

the expected dividend yield, which we estimate to be zero based on the fact that we have never paid cash dividends and have no present intention to pay cash dividends; and

•

the fair value of our common stock on the date of grant.

Income Taxes

Segment Reporting

We have determined that we operate in a single segment and have one reporting unit: the discovery, development, commercialization and sale of novel oncology and hematology therapeutics.

New Accounting Pronouncements

Sale of Hyperimmune Business (Tables)

12 Months Ended

Dec. 31, 2017

Discontinued Operations And Disposal Groups [Abstract]

Summary of Gain on Sale

The following table summarizes the gain on sale (in thousands):

Cash payment received	$	61,750
Escrow receivable		3,250
Collection of accounts receivable		37
Total consideration		65,037
Less:
Net carrying value of assets transferred to Saol		10,315
Transaction costs		1,273
Working capital adjustment		752
Net gain on sale of business	$	52,697

Summary of Reconciliation of Carrying Amounts of Assets and Liabilities of Hyperimmune Assets Held For Sale, Net in Consolidated Balance Sheet and Components Attributable to Hyperimmune Business Presented as Income from Discontinued Operations in Consolidated Statements of Operations

The following table presents a reconciliation of the carrying amounts of assets and liabilities of the hyperimmune assets held for sale, net in the consolidated balance sheet (in thousands):

ASSETS	December 31, 2016
Accounts receivable	$	3,977
Inventories		6,178
Total current assets, held for sale		10,155

Intangible assets, net		7,624
Total assets held for sale	$	17,779
LIABILITIES
Accounts payable and other accrued liabilities	$	3,928
Total current liabilities	$	3,928

The following table represents the components attributable to the Hyperimmune Business presented as income from discontinued operations in the consolidated statements of operations (in thousands):

	For the Year Ended December 31,
	2017			2016
Revenues:
Product sales	$	18,886		$	26,449
Total revenues		18,886			26,449
Costs and expenses:
Cost of product sales		7,730			11,715
Research and development		44			398
Selling, general and administrative		945			2,508
Income from operations		10,167			11,828
Gain on sale of Hyperimmune Business		52,697			—
Income from discontinued operations, before income taxes		62,864			11,828
Income tax expense		(23,299	)		(4,352	)
Income from discontinued operations	$	39,565		$	7,476

- Definition

Tabular disclosure of information related to a disposal group. Includes, but is not limited to, a discontinued operation, disposal classified as held-for-sale or disposed of by means other than sale or disposal of an individually significant component.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 45
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=65878427&loc=SL51721533-107759

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 50
-Paragraph 4B
-URI http://asc.fasb.org/extlink&oid=64827811&loc=SL51721665-107760

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=64827811&loc=d3e1474-107760

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=64827811&loc=d3e1361-107760

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 50
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=64827811&loc=SL51721683-107760

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 3A
-URI http://asc.fasb.org/extlink&oid=84176398&loc=SL51724579-110230

Reference 7: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 50
-Paragraph 5C
-URI http://asc.fasb.org/extlink&oid=64827811&loc=SL51721675-107760

Reference 8: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 50
-Paragraph 4A
-URI http://asc.fasb.org/extlink&oid=64827811&loc=SL51721663-107760

Reference 9: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=84176398&loc=d3e2941-110230

Reference 10: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 50
-Paragraph 5B
-URI http://asc.fasb.org/extlink&oid=64827811&loc=SL51721673-107760

Reference 11: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 50
-Paragraph 3A
-URI http://asc.fasb.org/extlink&oid=64827811&loc=SL51721659-107760

Reference 12: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 50
-Paragraph 5A
-URI http://asc.fasb.org/extlink&oid=64827811&loc=SL51721671-107760

Reference 13: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 50
-Paragraph 5D
-URI http://asc.fasb.org/extlink&oid=64827811&loc=SL51721677-107760

+ Details

Fair Value Measurements (Tables)

12 Months Ended

Dec. 31, 2017

Fair Value Disclosures [Abstract]

Summary of Financial Assets Measured at Fair Value

The Company’s financial assets measured at fair value consisted of the following as of December 31, 2017 and December 31, 2016:

	December 31, 2017
(in thousands)	Level 1		Level 2		Level 3		Total
Financial Assets:
Money market funds⁽¹⁾	$	10,997	$	—	$	—	$	10,997
Corporate bonds		—		16,443		—		16,443
US government and agency debt securities		—		33,300		—		33,300
Foreign government and agency debt securities		—		23,945		—		23,945
Total assets	$	10,997	$	73,688	$	—	$	84,685

	December 31, 2016
(in thousands)	Level 1		Level 2		Level 3		Total
Financial Assets:
Money market funds	$	5,215	$	—	$	—	$	5,215
Corporate bonds		—		9,951		—		9,951
US government and agency debt securities		—		34,898		—		34,898
Foreign government and agency debt securities		—		—		—		—
Total assets	$	5,215	$	44,849	$	—	$	50,064
⁽¹⁾ As of December 31, 2017, the money market funds included $10.0 million in restricted cash.

Investments (Tables)

12 Months Ended

Dec. 31, 2017

Investments Debt And Equity Securities [Abstract]

Schedule of short-term investments

All short-term investments are limited to a final maturity of less than one year from the reporting date.

	December 31, 2017
(in thousands)	Amortized Cost		Gross Unrealized Holding Gains		Gross Unrealized Holding (Losses)			Fair Value
Cash equivalents:
Money market funds⁽¹⁾	$	10,997	$	—	$	—		$	10,997
Total cash equivalents	$	10,997	$	—	$	—		$	10,997

Short-term investments:
Corporate bonds	$	16,455	$	—	$	(12	)	$	16,443
US government and agency debt securities		33,331		—		(31	)		33,300
Foreign government and agency debt securities		24,007		—		(62	)		23,945
Total short-term investments	$	73,793	$	—	$	(105	)	$	73,688

	December 31, 2016
(in thousands)	Amortized Cost		Gross Unrealized Holding Gains		Gross Unrealized Holding (Losses)			Fair Value
Cash equivalents:
Money market fund	$	5,215	$	—	$	—		$	5,215
Total cash equivalents	$	5,215	$	—	$	—		$	5,215

Short-term investments:
Corporate bonds	$	9,959	$	1	$	(9	)	$	9,951
US government and agency debt securities		34,923		—		(25	)		34,898
Foreign government and ageny debt securities		—		—		—			—
Total short-term investments	$	44,882	$	1	$	(34	)	$	44,849
⁽¹⁾ As of December 31, 2017, the money market funds included $10.0 million in restricted cash.

- Definition

Tabular disclosure of available-for-sale securities which includes, but is not limited to, changes in the cost basis and fair value, fair value and gross unrealized gain (loss), fair values by type of security, contractual maturity and classification, amortized cost basis, contracts to acquire securities to be accounted for as available-for-sale, debt maturities, transfers to trading, change in net unrealized holding gain (loss) net of tax, continuous unrealized loss position fair value, aggregate losses qualitative disclosures, other than temporary impairment (OTTI) losses or other disclosures related to available for sale securities.

+ References + Details

Inventories (Tables)

12 Months Ended

Dec. 31, 2017

Inventory Disclosure [Abstract]

Schedule of Inventories

Inventories consist of the following:

	December 31,		December 31,
(in thousands)	2017		2016
Raw materials and supplies	$	56	$	260
Work-in-process		482		4
Finished goods		490		197
Total inventories	$	1,028	$	461

Property and Equipment, Net (Tables)

12 Months Ended

Dec. 31, 2017

Property Plant And Equipment [Abstract]

Summary of Property, Plant and Equipment

Property, plant and equipment consist of the following:

	December 31,			December 31,
(in thousands)	2017			2016
Leasehold improvements	$	2,228		$	2,265
Furniture and equipment		11,139			10,283
Property and equipment, gross		13,367			12,548
Less: Accumulated depreciation		(7,524	)		(6,638	)
Total property and equipment, net	$	5,843		$	5,910

Intangible Assets, Net (Tables)

12 Months Ended

Dec. 31, 2017

Intangible Assets Net Excluding Goodwill [Abstract]

Schedule of Future Amortization Expense

Future amortization expense as of December 31, 2017 is as follows:

(in thousands)
2018	$	830
2019		830
2020		830
2021		830
2022 and beyond		2,760
Total remaining amortization	$	6,080

Debt (Tables)

12 Months Ended

Dec. 31, 2017

Debt Disclosure [Abstract]

Schedule of Future Principal and Interest Payment in Connection with Credit Agrement

Future principal and interest payments in connection with the Credit Agreement as of December 31, 2017 are as follows:

(in thousands)
2018	$	5,050
2019		9,147
2020		8,441
2021		2,022
Total principal and interest payments	$	24,660

Net Income (Loss) Per Share (Tables)

12 Months Ended

Dec. 31, 2017

Earnings Per Share [Abstract]

Computation of Basic and Diluted Net Income (Loss) per Share

The following table presents the computation of basic and diluted net income (loss) per share (in thousands, except share and per share amounts):

	For the Year Ended December 31,
	2017			2016
Net income (loss)	$	6,973		$	(112,415	)

Basic and diluted net income (loss) per share:
Net loss from continuing operations	$	(1.53	)	$	(5.92	)
Net income from discontinued operations	$	1.86		$	0.37
Net income (loss)	$	0.33		$	(5.55	)
Weighted-average shares used to compute per share calculation		21,335,157			20,239,160

Summary of Potentially Dilutive Shares Excluded from Calculation of Net Loss Per Share

The following table represents all potentially dilutive shares, which were all anti-dilutive and therefore excluded from the calculation of diluted net loss per share:

	For the Year Ended December 31,
(in thousands, except for per share amounts)	2017		2016
Outstanding options to purchase common stock		2,819		2,069
Unvested RSUs		1,211		3,034

Equity (Tables)

12 Months Ended

Dec. 31, 2017

Equity [Abstract]

Summary of Stock-based Compensation Expense Includes Amortization of Stock Options and Restricted Stock Units Granted

	For the Year Ended December 31,
(in thousands)	2017		2016
Research and development	$	2,256	$	2,693
Selling, general and administrative		2,628		1,116
Total stock-based compensation expense	$	4,884	$	3,809

Assumptions used in Valuing the Stock Options Granted under Black-Scholes Valuation Model

Aptevo utilizes the Black-Scholes valuation model for estimating the fair value of all stock options granted. Set forth below are the assumptions used in valuing the stock options granted:

	For the Year Ended December 31,
	2017	2016
Expected dividend yield	0.00%	0.00%
Expected volatility	75.00%	75.00%
Risk-free interest rate	1.90%	1.00%
Expected average life of options	6 years	3 years

Summary of Stock Option Activity

The following is a summary of option activity for the year ended December 31, 2017:

	Number of Shares			Weighted- Average Exercise Price		Weighted- Average Remaining Term		Aggregate Intrinsic Value
Balance at December 31, 2016		2,085,214		$	2.57			$	164,767
Granted		1,071,189			2.11				—
Exercised		(204,275	)		4.15				334,268
Forfeited		(132,784	)		2.31				45,557
Outstanding at December 31, 2017		2,819,344		$	2.41		6.92	$	5,156,881
Exercisable at December 31, 2017		1,089,510		$	2.45		4.53	$	1,976,638

Summary of Restricted Stock Activity

The following is a summary of restricted stock activity for the year ended December 31, 2017:

	Number of Units			Weighted Average Fair Value per Unit		Aggregate Fair Value
Balance at December 31, 2016		3,034,195		$	2.88	$	7,406,256
Granted		19,803			2.00		37,118
Vested		(1,558,642	)		2.84		2,973,951
Forfeited		(283,869	)		2.94		597,483
Outstanding at December 31, 2017		1,211,487		$	2.91	$	5,136,705
Expected to Vest		1,174,656		$	2.91	$	4,980,541

Leases and Contingencies (Tables)

12 Months Ended

Dec. 31, 2017

Leases [Abstract]

Summary of Future Minimum Lease Payments Under Operating Lease Agreements

As of December 31, 2017, we are committed to future minimum lease payments under operating lease agreements as follows:

(in thousands)
2018	$	1,713
2019		1,611
2020		543
Total	$	3,867

Income Taxes (Tables)

12 Months Ended

Dec. 31, 2017

Income Tax Disclosure [Abstract]

Summary of Significant Components of Benefits for Income Taxes Attributable to Continuing Operations

Significant components of the benefits for income taxes attributable to continuing operations consist of the following:

	Year ended December 31,
(in thousands)	2017		2016
Current
Federal	$	12,051	$	4,255
State		710		218
International		2		29
Total current		12,763		4,502
Deferred
Federal		9,636		14,518
State		902		672
International		—		—
Total deferred		10,538		15,190
Total income tax benefit from continuing operations	$	23,301	$	19,692

Schedule of Loss from Continuing Operations Before Income Taxes

Loss from continuing operations before income taxes is comprised of:

	Year ended December 31,
(in thousands)	2017			2016
US	$	(55,885	)	$	(139,578	)
International		(8	)		(5	)
Loss from continuing operations before benefit from income taxes	$	(55,893	)	$	(139,583	)

Schedule of Tax Effects of Temporary Differences Give Rise to Significant Portions of Deferred Tax Assets and Deferred Tax Liabilities

The tax effects of temporary differences that give rise to significant portions of the deferred tax assets and deferred tax liabilities are presented below:

	December 31,
(in thousands)	2017			2016
Federal losses carryforward	$	8,454		$	7,237
Intangible assets		4,470			17,464
Stock compensation		1,128			1,726
State losses carryforward		1,246			371
Other		1,262			3,050
Other tax credits		502			384
Fixed assets		309			160
Deferred tax asset		17,371			30,392
Prepaid expenses		(224	)		(575	)
Deferred tax liability		(224	)		(575	)
Valuation allowance		(17,147	)		(29,817	)
Net deferred tax liabilities	$	—		$	—

Schedule of Reconciliation of Federal Statutory Income Tax Rate to Effective Income Tax from Continuing Operations

The reconciliation of the federal statutory income tax rate to the Company’s effective income tax from continuing operations is as follows:

	Year ended December 31,
	2017			2016
Federal tax at statutory rates		35.0	%		35.0	%
State taxes, net of federal benefit		2.4	%		1.0	%
Change in valuation allowance		22.7	%		-6.8	%
Tax credits		0.6	%		0.3	%
Permanent differences		-0.3	%		-7.4	%
Separation related adjustment		—			-7.9	%
Other		-1.3	%		-0.1	%
Tax Reform		-17.4	%		—
Total income tax benefit		41.7	%		14.1	%

Nature of Business and Significant Accounting Policies - Additional Information (Details) $ in Millions	12 Months Ended
	Dec. 31, 2017 USD ($) Product Segment Unit	Dec. 31, 2016	Aug. 06, 2015 Company
Nature Of Business [Line Items]
Number of revenue-generating product \| Product	1
Month and year of incorporation	2016-02
Spin off transaction separation distribution agreement date	Aug. 01, 2016
Restricted cash	$ 10.4
Number of operating segment \| Segment	1
Number of reporting unit \| Unit	1
Stock Option
Nature Of Business [Line Items]
Expected dividend yield	0.00%	0.00%
Estimated forfeiture rate	10.00%
RSUs and Options
Nature Of Business [Line Items]
Estimated forfeiture rate	10.00%
Covenant of MidCap Loan Agreement
Nature Of Business [Line Items]
Restricted cash	$ 10.0
Collateral for Corporate Credit Cards
Nature Of Business [Line Items]
Restricted cash	$ 0.4
Emergent
Nature Of Business [Line Items]
Number of independent publicly traded companies \| Company			2

Nature of Business and Significant Accounting Policies - Schedule of Estimated Useful Lives of Property and Equipment (Details)	12 Months Ended
	Dec. 31, 2017
Furniture and Equipment \| Minimum
Property Plant And Equipment [Line Items]
Estimated useful lives	7 years
Furniture and Equipment \| Maximum
Property Plant And Equipment [Line Items]
Estimated useful lives	10 years
Software and Hardware
Property Plant And Equipment [Line Items]
Estimated useful lives	product life
Software and Hardware \| Minimum
Property Plant And Equipment [Line Items]
Estimated useful lives	3 years
Software and Hardware \| Maximum
Property Plant And Equipment [Line Items]
Estimated useful lives	5 years
Leasehold Improvements
Property Plant And Equipment [Line Items]
Estimated useful lives	Lesser of the asset life or the remaining lease term

Sale of Hyperimmune Business - Additional Information (Details) - USD ($)			12 Months Ended
	Sep. 28, 2017	Aug. 31, 2017	Dec. 31, 2017	Dec. 31, 2016
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Net gain on sale of business			$ 52,697,000
Hyperimmune Business
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Business sale agreement date		Aug. 31, 2017
Business sale completion date	Sep. 28, 2017
Cash payment received	$ 65,037,000
Escrow receivable	3,250,000
Net gain on sale of business	52,697,000		52,697,000
Amortization			800,000	$ 1,200,000
Depreciation			0	0
Capital expenditures			0	0
Other non-cash operating activities			0	0
Other non-cash investing activities			$ 0	$ 0
Hyperimmune Business \| Maximum
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Additional potential milestone payment related to gross profit	7,500,000
Additional potential milestone payment related to accounts receivable	$ 2,000,000

Sale of Hyperimmune Business - Summary of Gain on Sale (Details) - USD ($) $ in Thousands		12 Months Ended
	Sep. 28, 2017	Dec. 31, 2017	Dec. 31, 2016
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Net gain on sale of business		$ 52,697
Hyperimmune Business
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Cash payment received	$ 61,750
Escrow receivable	3,250
Collection of accounts receivable	37		$ 3,977
Total consideration	65,037
Net carrying value of assets transferred to Saol	10,315		$ 17,779
Transaction costs	1,273
Working capital adjustment	752
Net gain on sale of business	$ 52,697	$ 52,697

Sale of Hyperimmune Business - Summary of Reconciliation of Carrying Amounts of Assets and Liabilities of Hyperimmune Assets Held For Sale, Net in Consolidated Balance Sheet (Details) - USD ($) $ in Thousands	Sep. 28, 2017	Dec. 31, 2016
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Total current assets, held for sale		$ 10,155
Total current liabilities		3,928
Hyperimmune Business
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Accounts receivable	$ 37	3,977
Inventories		6,178
Total current assets, held for sale		10,155
Intangible assets, net		7,624
Total assets held for sale	$ 10,315	17,779
Accounts payable and other accrued liabilities		3,928
Total current liabilities		$ 3,928

Sale of Hyperimmune Business - Summary of Components Attributable to Hyperimmune Business Presented as Income from Discontinued Operations in Consolidated Statements of Operations (Details) - USD ($) $ in Thousands		12 Months Ended
	Sep. 28, 2017	Dec. 31, 2017	Dec. 31, 2016
Costs and expenses:
Gain on sale of Hyperimmune Business		$ 52,697
Income from discontinued operations, before income taxes		62,864	$ 11,828
Income tax expense		(23,299)	(4,352)
Income from discontinued operations		39,565	7,476
Hyperimmune Business
Revenues:
Product sales		18,886	26,449
Total revenues		18,886	26,449
Costs and expenses:
Cost of product sales		7,730	11,715
Research and development		44	398
Selling, general and administrative		945	2,508
Income from operations		10,167	11,828
Gain on sale of Hyperimmune Business	$ 52,697	52,697
Income from discontinued operations, before income taxes		62,864	11,828
Income tax expense		(23,299)	(4,352)
Income from discontinued operations		$ 39,565	$ 7,476

Collaboration Agreement - Additional Information (Details) $ in Millions	Sep. 30, 2017 USD ($)
MorphoSys Agreement
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Deferred revenue	$ 3.7

Fair Value Measurements - Summary of Financial Assets Measured at Fair Value (Details) - USD ($)
$ in Thousands

Dec. 31, 2017

Dec. 31, 2016

Financial Assets:

Assets fair value

$ 84,685

$ 50,064

Money Market Funds

Financial Assets:

Assets fair value

10,997

^[1]

5,215

Corporate Bonds

Financial Assets:

Assets fair value

16,443

9,951

US Government and Agency Debt Securities

Financial Assets:

Assets fair value

33,300

34,898

Foreign Government and Agency Debt Securities

Financial Assets:

Assets fair value

23,945

Level 1

Financial Assets:

Assets fair value

10,997

5,215

Level 1 | Money Market Funds

Financial Assets:

Assets fair value

10,997

^[1]

5,215

Level 2

Financial Assets:

Assets fair value

73,688

44,849

Level 2 | Corporate Bonds

Financial Assets:

Assets fair value

16,443

9,951

Level 2 | US Government and Agency Debt Securities

Financial Assets:

Assets fair value

33,300

$ 34,898

Level 2 | Foreign Government and Agency Debt Securities

Financial Assets:

Assets fair value

$ 23,945

[1]	As of December 31, 2017, the money market funds included $10.0 million in restricted cash.

Investments - Schedule of Short-term Investments (Details) - USD ($)
$ in Thousands

Dec. 31, 2017

Dec. 31, 2016

Short-term Investments

Schedule Of Available For Sale Securities [Line Items]

Amortized Cost

$ 73,793

$ 44,882

Gross Unrealized Holding Gains

Gross Unrealized Holding (Losses)

(105)

(34)

Fair Value

73,688

44,849

Short-term Investments | Corporate Bonds

Schedule Of Available For Sale Securities [Line Items]

Amortized Cost

16,455

9,959

Gross Unrealized Holding Gains

Gross Unrealized Holding (Losses)

(12)

(9)

Fair Value

16,443

9,951

Short-term Investments | US Government and Agency Debt Securities

Schedule Of Available For Sale Securities [Line Items]

Amortized Cost

33,331

34,923

Gross Unrealized Holding Gains

Gross Unrealized Holding (Losses)

(31)

(25)

Fair Value

33,300

34,898

Short-term Investments | Foreign Government and Agency Debt Securities

Schedule Of Available For Sale Securities [Line Items]

Amortized Cost

24,007

Gross Unrealized Holding (Losses)

(62)

Fair Value

23,945

Cash Equivalents

Schedule Of Available For Sale Securities [Line Items]

Amortized Cost

10,997

5,215

Gross Unrealized Holding Gains

Gross Unrealized Holding (Losses)

Fair Value

10,997

5,215

Cash Equivalents | Money Market Funds

Schedule Of Available For Sale Securities [Line Items]

Amortized Cost

10,997

^[1]

5,215

Gross Unrealized Holding Gains

^[1]

Gross Unrealized Holding (Losses)

^[1]

Fair Value

$ 10,997

^[1]

$ 5,215

[1]	As of December 31, 2017, the money market funds included $10.0 million in restricted cash.

Inventories - Schedule of Inventories (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Inventory Adjustments [Abstract]
Raw materials and supplies	$ 56	$ 260
Work-in-process	482	4
Finished goods	490	197
Total inventories	$ 1,028	$ 461

Property and Equipment, Net - Summary of Property, Plant and Equipment (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 13,367	$ 12,548
Less: Accumulated depreciation	(7,524)	(6,638)
Total property and equipment, net	5,843	5,910
Leasehold Improvements
Property Plant And Equipment [Line Items]
Property and equipment, gross	2,228	2,265
Furniture and Equipment
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 11,139	$ 10,283

Intangible Assets, Net - Additional Information (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Intangible Assets Net Excluding Goodwill [Abstract]
Amortization expense	$ 0.8	$ 0.8
Weighted average remaining amortization period	88 months

Intangible Assets, Net - Schedule of Future Amortization Expense (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Finite Lived Intangible Assets Future Amortization Expense [Abstract]
2018	$ 830
2019	830
2020	830
2021	830
2022 and beyond	2,760
Net book value at December 31, 2017	$ 6,080	$ 6,910

Debt - Additional Information (Details) - USD ($)				12 Months Ended
Debt - Additional Information (Details) - USD ($)	Sep. 28, 2017	May 11, 2017	Aug. 04, 2016	Dec. 31, 2017	Jan. 13, 2017
Line Of Credit Facility [Line Items]
Maximum borrowing capacity			$ 35,000,000
Credit facility repayment term, description				The loan repayment included interest (no principal) through August 2018 and was set to transition to principal and interest as of August 2018 and to be repaid in full on February 1, 2021 (54 months).
Credit facility repayment period			54 months
Maturity date of credit agreement			Feb. 01, 2021
Credit agreement reference rate for the variable rate				LIBOR
Credit agreement basis spread on variable rate			7.60%
Cash funding committed by Emergent in connection with spin-off					$ 20,000,000
Unamortized debt issuance costs				$ 1,400,000
Credit agreement exit fee, percentage			5.75%
Credit agreement final principal payment, percentage		6.75%
Credit agreement minimum cash threshold required amount		$ 25,000,000
Line of Credit
Line Of Credit Facility [Line Items]
Debt issuance costs				$ 1,900,000
Credit Facility First Tranche
Line Of Credit Facility [Line Items]
Maximum borrowing capacity			$ 20,000,000
Credit Facility Second Tranche
Line Of Credit Facility [Line Items]
Maximum borrowing capacity			15,000,000
Net commercial product revenue required to be achieved on trailing twelve month basis	$ 16,000,000		$ 40,000,000
Maximum borrowing capacity withdrawal date of tranche		2018-03	2017-08
Terminated maximum borrowing capacity	$ 15,000,000
Term loans extended amortization date based on net commercial product revenues recognized	Feb. 01, 2019
Net commercial product revenue, date to be achieved	Jun. 30, 2018
Net commercial product revenue requirements to be maintained				The date on which the term loans begin to amortize will be extended to February 1, 2019 if the Company achieves net commercial product revenues of $16 million for the twelve month period ending June 30, 2018 and maintains such level of net commercial product revenues for each quarter prior to February 1, 2019 thereafter.
Credit Facility Second Tranche \| Minimum
Line Of Credit Facility [Line Items]
Unrestricted cash balance	$ 10,000,000

Debt - Schedule of Future Principal and Interest Payment in Connection with Credit Agrement (Details) $ in Thousands	Dec. 31, 2017 USD ($)
Debt Disclosure [Abstract]
2018	$ 5,050
2019	9,147
2020	8,441
2021	2,022
Total principal and interest payments	$ 24,660

Net Income (Loss) Per Share - Additional Information (Details) - shares	Dec. 31, 2017	Dec. 31, 2016
Schedule Of Earnings Per Share Basic And Diluted [Line Items]
Ordinary shares outstanding	21,605,716	20,271,737
Ordinary shares issued in connection with spin-off	21,605,716	20,271,737
Emergent
Schedule Of Earnings Per Share Basic And Diluted [Line Items]
Ordinary shares outstanding	1,000
Spin-off
Schedule Of Earnings Per Share Basic And Diluted [Line Items]
Ordinary shares issued in connection with spin-off	20,229,849

Net Income (Loss) Per Share - Computation of Basic and Diluted Net Income (Loss) per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Earnings Per Share [Abstract]
Net income (loss)	$ 6,973	$ (112,415)
Basic and diluted net income (loss) per share:
Net loss from continuing operations	$ (1.53)	$ (5.92)
Net income from discontinued operations	1.86	0.37
Net income (loss)	$ 0.33	$ (5.55)
Weighted-average shares used to compute per share calculation	21,335,157	20,239,160

Net Income (Loss) Per Share - Summary of Potentially Dilutive Shares Excluded from Calculation of Net Loss Per Share (Details) - shares shares in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Outstanding Options to Purchase Common Stock
Schedule Of Earnings Per Share Basic And Diluted [Line Items]
Anti-dilutive shares excluded from calculation of diluted net loss per share	2,819	2,069
Unvested RSUs
Schedule Of Earnings Per Share Basic And Diluted [Line Items]
Anti-dilutive shares excluded from calculation of diluted net loss per share	1,211	3,034

Equity - Additional Information (Details) - USD ($)		12 Months Ended
Equity - Additional Information (Details) - USD ($)	Aug. 02, 2016	Dec. 31, 2017	Aug. 01, 2016
Stock Option
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Estimated forfeiture rate		10.00%
Unrecognized compensation expense		$ 1,600,000
Options expected to vest , weighted average period		2 years
Options outstanding and exercisable weighted average remaining contractual life		6 years 9 months 18 days
RSUs
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unrecognized compensation expense		$ 700,000
Expected vesting period		9 months 18 days
Weighted average remaining contractual life		2 years 3 months 18 days
Converted Equity Awards Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Incremental stock-based compensation expense recorded as result of equity award conversion	$ 0
Converted Equity Awards Incentive Plan \| Common Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock authorized for issuance under Stock Plan			1,300,000
2016 Stock Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock authorized for issuance under Stock Plan			3,100,000

Equity - Summary of Stock-based Compensation Expense Includes Amortization of Stock Options and Restricted Stock Units Granted (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense	$ 4,884	$ 3,809
Research and Development
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense	2,256	2,693
Selling, General and Administrative
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense	$ 2,628	$ 1,116

Equity - Assumptions used in Valuing the Stock Options Granted under Black-Scholes Valuation Model (Details) - Stock Option	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected dividend yield	0.00%	0.00%
Expected volatility	75.00%	75.00%
Risk-free interest rate	1.90%	1.00%
Expected average life of options	6 years	3 years

Equity - Summary of Stock Option Activity (Details) - Stock Option	12 Months Ended
	Dec. 31, 2017 USD ($) $ / shares shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of Shares, Outstanding, Beginning balance \| shares	2,085,214
Number of Shares, Granted \| shares	1,071,189
Number of Shares, Exercised \| shares	(204,275)
Number of Shares, Forfeited \| shares	(132,784)
Number of Shares, Outstanding, Ending balance \| shares	2,819,344
Number of Shares, Exercisable \| shares	1,089,510
Weighted-Average Exercise Price, Outstanding, Beginning balance \| $ / shares	$ 2.57
Weighted-Average Exercise Price, Granted \| $ / shares	2.11
Weighted-Average Exercise Price, Exercised \| $ / shares	4.15
Weighted-Average Exercise Price, Forfeited \| $ / shares	2.31
Weighted-Average Exercise Price, Outstanding, Ending balance \| $ / shares	2.41
Weighted-Average Exercise Price, Exercisable \| $ / shares	$ 2.45
Weighted-Average Remaining Term, Outstanding	6 years 11 months 1 day
Weighted-Average Remaining Term, Exercisable	4 years 6 months 10 days
Aggregate Intrinsic Value, Outstanding, Beginning balance \| $	$ 164,767
Aggregate Intrinsic Value, Exercised \| $	334,268
Aggregate Intrinsic Value, Forfeited \| $	45,557
Aggregate Intrinsic Value, Outstanding, Ending balance \| $	5,156,881
Aggregate Intrinsic Value, Exercisable \| $	$ 1,976,638

Equity - Summary of Restricted Stock Activity (Details) - RSUs	12 Months Ended
	Dec. 31, 2017 USD ($) $ / shares shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of Units, Outstanding, Beginning balance \| shares	3,034,195
Number of Units, Granted \| shares	19,803
Number of Units, Vested \| shares	(1,558,642)
Number of Units, Forfeited \| shares	(283,869)
Number of Units, Outstanding, Ending balance \| shares	1,211,487
Number of Units, Expected to Vest \| shares	1,174,656
Weighted Average Fair Value per Unit, Outstanding Beginning Balance \| $ / shares	$ 2.88
Weighted Average Fair Value per Unit, Granted \| $ / shares	2.00
Weighted Average Fair Value per Unit, Vested \| $ / shares	2.84
Weighted Average Fair Value per Unit, Forfeited \| $ / shares	2.94
Weighted Average Fair Value per Unit, Outstanding Ending Balance \| $ / shares	2.91
Weighted Average Fair Value per Unit, Expected to Vest \| $ / shares	$ 2.91
Aggregate Fair Value, Outstanding, Beginning balance \| $	$ 7,406,256
Aggregate Fair Value, Granted \| $	37,118
Aggregate Fair Value, Vested \| $	2,973,951
Aggregate Fair Value, Forfeited \| $	597,483
Aggregate Fair Value, Outstanding, Ending balance \| $	5,136,705
Aggregate Fair Value, Expected to Vest \| $	$ 4,980,541

401(K) Savings Plan - Additional Information (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Defined Contribution Plan Disclosure [Line Items]
Maximum employee deferral rate	6.00%
Matching contributions made by employer	$ 0.5	$ 0.3
Maximum
Defined Contribution Plan Disclosure [Line Items]
Employer matching contribution, qualified deferral percentage	50.00%

Leases and Contingencies - Summary of Future Minimum Lease Payments Under Operating Lease Agreements (Details) $ in Thousands	Dec. 31, 2017 USD ($)
Leases [Abstract]
2018	$ 1,713
2019	1,611
2020	543
Total	$ 3,867

Income Taxes - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Taxes [Line Items]
U.S. federal statutory tax rate, percent		35.00%	35.00%
Limitation of taxable income for NOL carryforward percentage		80.00%
Tax cuts and jobs act description		On December 22, 2017 the President of the United State signed into law Public Law No. 115-97, commonly referred to as the Tax Cuts and Jobs Act (the Tax Act), following its passage by the United States Congress. The Tax Act will make significant changes to U.S. federal income tax laws, including reduction of the corporate tax rate from 35.0% to 21.0%, limitation of the deduction for net operating losses to 80.0% of current year taxable income and elimination of net operating loss carrybacks, one-time taxation of offshore earning at reduced rates regardless of whether they are repatriated, elimination of U.S. tax on foreign earnings (subject to certain important exceptions), immediate deductions for certain new investments instead of deductions for depreciation expense over time, and modifying or repealing many business deductions.
Provisional amount related to re-measurement of deferred tax assets and liabilities expected to reverse future		$ 10,000,000
Total tax expense related to valuation allowance		0
Transition tax on mandatory deemed repatriation of foreign earnings		20,000
Cumulative foreign earnings		60,000
Income tax expense from discontinued operations		23,299,000	$ 4,352,000
Deferred tax assets from discontinued operations		0	10,400,000
Uncertain income tax positions		0	0
Federal
Income Taxes [Line Items]
Net operating loss carryforwards		41,500,000	20,700,000
State
Income Taxes [Line Items]
Net operating loss carryforwards		20,200,000	9,000,000
Tax credit carryforwards		$ 500,000	$ 400,000
Earliest Tax Year \| Federal
Income Taxes [Line Items]
Operating losses, begin to expiration year		2037
Tax credits, begin to expiration year		2037
Scenario, Forecast
Income Taxes [Line Items]
U.S. federal statutory tax rate, percent	21.00%

Income Taxes - Summary of Significant Components of Benefits for Income Taxes Attributable to Continuing Operations (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Current
Federal	$ 12,051	$ 4,255
State	710	218
International	2	29
Total current	12,763	4,502
Deferred
Federal	9,636	14,518
State	902	672
Total deferred	10,538	15,190
Total income tax benefit from continuing operations	$ 23,301	$ 19,692

Income Taxes - Schedule of Loss from Continuing Operations Before Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Income Tax Disclosure [Abstract]
US	$ (55,885)	$ (139,578)
International	(8)	(5)
Loss before income taxes	$ (55,893)	$ (139,583)

Income Taxes - Schedule of Tax Effects of Temporary Differences Give Rise to Significant Portions of Deferred Tax Assets and Deferred Tax Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Income Tax Disclosure [Abstract]
Federal losses carryforward	$ 8,454	$ 7,237
Intangible assets	4,470	17,464
Stock compensation	1,128	1,726
State losses carryforward	1,246	371
Other	1,262	3,050
Other tax credits	502	384
Fixed assets	309	160
Deferred tax asset	17,371	30,392
Prepaid expenses	(224)	(575)
Deferred tax liability	(224)	(575)
Valuation allowance	$ (17,147)	$ (29,817)

Income Taxes - Schedule of Reconciliation of Federal Statutory Income Tax Rate to Effective Income Tax from Continuing Operations (Details)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Income Tax Disclosure [Abstract]
Federal tax at statutory rates	35.00%	35.00%
State taxes, net of federal benefit	2.40%	1.00%
Change in valuation allowance	22.70%	(6.80%)
Tax credits	0.60%	0.30%
Permanent differences	(0.30%)	(7.40%)
Separation related adjustment		(7.90%)
Other	(1.30%)	(0.10%)
Tax Reform	(17.40%)
Total income tax benefit	41.70%	14.10%

401(K) Savings Plan	12 Months Ended
401(K) Savings Plan	Dec. 31, 2017
Compensation And Retirement Disclosure [Abstract]
401(K) Savings Plan	Note 12. 401(k) savings plan Aptevo has established a defined contribution savings plan under Section 401(k) of the Internal Revenue Code. The 401(k) Plan covers all employees. Under the 401(k) Plan, employees may make elective salary deferrals. Aptevo currently provides for matching of qualified deferrals up to 50% of 401(k) employee deferral contributions, based on a maximum employee deferral rate of 6% of compensation. During the year ended December 31, 2017 and December 31, 2016, Aptevo’s related share of matching contributions was approximately $0.5 million and $0.3 million.

Investments - Schedule of Short-term Investments (Parenthetical) (Details) $ in Millions	Dec. 31, 2017 USD ($)
Available For Sale Securities [Abstract]
Amount of money market funds included in restricted cash	$ 10.0

Inventories - Additional Information (Details) $ in Millions	12 Months Ended
	Dec. 31, 2016 USD ($)
Inventory Adjustments [Abstract]
Inventory Write-down	$ 7.1

Fair Value Measurements - Additional Information (Details)	Dec. 31, 2017 USD ($)
Fair Value Disclosures [Abstract]
Fair value assets, level 1 to level 2 transfers	$ 0
Fair value assets, level 2 to level 1 transfers	$ 0