Document and Entity Information - shares	3 Months Ended
Document and Entity Information - shares	Mar. 31, 2019	May 07, 2019
Document And Entity Information [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Mar. 31, 2019
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	Q1
Trading Symbol	APVO
Entity Registrant Name	APTEVO THERAPEUTICS INC.
Entity Central Index Key	0001671584
Current Fiscal Year End Date	--12-31
Entity Filer Category	Accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	true
Entity Extended Transition Period	true
Entity Common Stock, Shares Outstanding		45,090,219

CONDENSED CONSOLIDATED BALANCE SHEETS (Unaudited) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Current assets:
Cash and cash equivalents	$ 37,011	$ 30,635
Accounts receivable	5,801	5,220
Inventories	4,346	1,785
Prepaid expenses	6,923	6,907
Other current assets	3,561	4,142
Total current assets	57,642	48,689
Restricted cash	7,448	7,448
Property and equipment, net	4,978	5,202
Intangible assets, net	5,043	5,250
Operating lease right-of-use asset	4,481
Other assets	1,249	905
Total assets	80,841	67,494
Current liabilities:
Accounts payable	11,043	11,671
Accrued compensation	5,042	3,898
Sales rebates and discounts payable	857	1,245
Other short-term liabilities	1,348	796
Total current liabilities	18,290	17,610
Long-term debt, net	19,415	19,278
Operating lease liability, net of current portion	3,995
Other liabilities	11	200
Total liabilities	41,711	37,088
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; 45,090,219 and 22,808,416 shares issued and outstanding at March 31, 2019 and December 31, 2018, respectively	45	23
Additional paid-in capital	178,511	157,791
Accumulated deficit	(139,426)	(127,408)
Total stockholders' equity	39,130	30,406
Total liabilities and stockholders' equity	$ 80,841	$ 67,494

CONDENSED CONSOLIDATED BALANCE SHEETS (Unaudited) (Parenthetical) - $ / shares	Mar. 31, 2019	Dec. 31, 2018
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	45,090,219	22,808,416
Common stock, shares outstanding	45,090,219	22,808,416

CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Revenues:
Product sales	$ 7,022	$ 4,071
Type of Revenue [Extensible List]	us-gaap:ProductMember	us-gaap:ProductMember
Costs and expenses:
Cost of product sales	$ 3,847	$ 1,781
Type of Cost, Good or Service [Extensible List]	us-gaap:ProductMember	us-gaap:ProductMember
Research and development	$ 7,285	$ 8,199
Selling, general and administrative	7,330	7,592
Loss from operations	(11,440)	(13,501)
Other expense, net	(578)	(353)
Net loss	$ (12,018)	$ (13,854)
Basic and diluted net loss per basic share	$ (0.44)	$ (0.63)
Weighted-average shares used to compute per share calculations	27,567,584	22,025,268

CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Statement Of Income And Comprehensive Income [Abstract]
Net loss	$ (12,018)	$ (13,854)
Other comprehensive loss:
Unrealized loss on available-for-sale investments, net		22
Total comprehensive loss	$ (12,018)	$ (13,832)

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References + Details

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Operating Activities
Net loss	$ (12,018)	$ (13,854)
Adjustments to reconcile net loss to net cash used in operating activities:
Stock-based compensation	594	717
Depreciation and amortization	583	587
Non-cash interest expense and other	198	60
Changes in operating assets and liabilities:
Accounts receivable	(581)	(957)
Inventories	(2,561)	(257)
Prepaid expenses and other current assets	121	97
Operating lease right of use asset	211
Accounts payable, accrued compensation and other liabilities	368	(3,371)
Long-term operating lease liability	(371)
Sales rebates and discounts	(388)
Net cash used in operating activities	(13,844)	(16,978)
Investing Activities
Proceeds from the maturity of investments		25,929
Cash received from sale of Hyperimmune Business		54
Purchases of property and equipment	(153)	(473)
Purchases of investments		(1,998)
Net cash (used in) provided by investing activities	(153)	23,512
Financing Activities
Proceeds from issuance of common stock, warrants, and pre-funded warrants, net	20,410
Proceeds from exercise of common stock options		186
Proceeds from the exercise of pre-funded warrants	21
Payment of tax liability for vested equity awards	(58)	(742)
Net cash provided by (used in) financing activities	20,373	(556)
Increase in cash, cash equivalents, and restricted cash	6,376	5,978
Cash, cash equivalents, and restricted cash at beginning of period	38,083	17,495
Cash, cash equivalents, and restricted cash at end of period	$ 44,459	$ 23,473

CONDENSED CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS' EQUITY (Unaudited) - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-In Capital	Accumulated Deficit	Accumulated Other Comprehensive Loss
Balance at Dec. 31, 2017	$ 82,035	$ 22	$ 155,837	$ (73,719)	$ (105)
Balance (in shares) at Dec. 31, 2017		21,605,716
Unrealized losses on available-for-sale investments	22				22
Common stock issued upon exercise of stock options	186		186
Common stock issued upon exercise of stock options (in shares)		75,425
Common stock issued upon vesting of restricted stock units	(742)		(742)
Common stock issued upon vesting of restricted stock units (in shares)		760,833
Stock-based compensation	717		717
Net loss for the period	(13,854)			(13,854)
Balance at Mar. 31, 2018	68,364	$ 22	155,998	(87,573)	$ (83)
Balance (in shares) at Mar. 31, 2018		22,441,974
Balance at Dec. 31, 2018	30,406	$ 23	157,791	(127,408)
Balance (in shares) at Dec. 31, 2018		22,808,416
Issuance of common stock, pre-funded warrants and warrants, net	20,206	$ 22	20,184
Issuance of common stock, pre-funded warrants and warrants, net (in shares)		22,000,000
Issuance of commitment shares of common stock, non-cash transaction (in shares)		195,867
Common stock issued upon vesting of restricted stock units	(58)		(58)
Common stock issued upon vesting of restricted stock units (in shares)		85,936
Stock-based compensation	594		594
Net loss for the period	(12,018)			(12,018)
Balance at Mar. 31, 2019	$ 39,130	$ 45	$ 178,511	$ (139,426)
Balance (in shares) at Mar. 31, 2019		45,090,219

Nature of Business and Significant Accounting Policies

3 Months Ended

Mar. 31, 2019

Accounting Policies [Abstract]

Nature of Business and Significant Accounting Policies

Note 1. Nature of Business and Significant Accounting Policies

Organization and Liquidity

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 areas of immuno-oncology and autoimmune and inflammatory diseases.

We are currently trading on the Nasdaq Global Market under the symbol “APVO.”

In accordance with Financial Accounting Standards Board, or the FASB, Accounting Standards Update No. 2014-15, Presentation of Financial Statements - Going Concern (Subtopic 205-40), our management evaluates whether there are conditions or events, considered in aggregate, that raise substantial doubt about our ability to continue as a going concern within one year after the date that the financial statements are issued. As of May 9, 2019, there are not such conditions or events, as we expect our existing cash and cash equivalents will be sufficient to fund our operations through May 9, 2020.

In March 2019, we completed a public offering relating to the issuance and sale of 19,850,000 shares of our common stock and warrants to purchase up to 19,850,000 shares of common stock at an exercise price of $1.30 per share, as well as pre-funded warrants to purchase up to 2,150,000 shares of common stock at an exercise price of $0.01 per share and 2,150,000 of related warrants to purchase shares of common stock at $1.30 per share. We received net proceeds of $20.2 million, after underwriting fees, legal fees, and other expenses. If the remaining warrants are fully exercised in the future, additional proceeds to be received upon exercise of these warrants totals up to $28.6 million over the ten-year term of the warrants.

Our results of operations will be highly dependent on IXINITY sales unless or until we develop or partner any of our development stage product candidates, which we expect may take a number of years and is subject to significant uncertainty. If we obtain regulatory approval for one of our development stage product candidates, we expect to incur significant commercialization expenses related to sales, marketing, manufacturing and distribution, to the extent that such costs are not paid by collaborators. We do not have sufficient cash to complete the clinical development of any of our development stage product candidates and will require additional funding in order to complete the development activities required for regulatory approval of such product candidates. While we may be able to access capital under our existing equity sales agreement with Lincoln Park Financial LLC or our Equity Distribution Agreement with Piper Jaffray, if we are unable to obtain additional financing when needed, or if IXINITY revenue growth does not continue or continue at the rates we expect, we may have to delay, reduce the scope of, suspend or eliminate one or more of our research and development programs.

Basis of Presentation

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

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.

The condensed 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.

Significant Accounting Policies

Leases

On January 1, 2019 we adopted ASU No. 2016-02, Leases (ASC 842), which amends the existing standards for lease accounting, requiring lessees to recognize most leases on their balance sheets and disclose key information about leasing arrangements. We adopted the new standard using a modified retrospective transition approach for the leases at the beginning of the current fiscal year, January 1, 2019. We did not adjust comparative periods in our financial statements prior to that period. See note 6 – Leases, of our condensed consolidated financial statements for additional information.

The new standard establishes a right-of-use model that requires a lessee to recognize an operating lease right-of-use asset and lease liability on the balance sheet for all leases with a term longer than twelve months. Leases are to be classified as finance or operating at the lease commencement, which affects the classification of expense recognition in the income statement. Right-of-use assets represent the right to use an underlying asset for the lease term and lease liabilities represent the obligation to make lease payments, as agreed to in the lease. Operating lease liabilities are recognized at the date of lease commencement based on the present value of lease payments over the lease term. As leases may include options to extend the lease period, or options for early termination, when it is reasonably certain that an entity is going to exercise the renewal option, the additional payments are to be included in the lease’s terms. When it is reasonably certain that an early termination option will not be exercised, the lease’s terms are to be extended beyond the possible early termination date or dates.

The standard requires that we use our incremental borrowing rate (IBR) as the discount rate in our lease evaluation if a rate implicit in the lease cannot be identified. Due to the significant judgment involved and the complex analysis needed to determine this discount rate, we engaged a third-party valuation specialist to advise us in our determination of our IBR.

An operating right-of-use asset is measured as the amount of the initial measurement of the lease liability, adjusted for prepaid or accrued lease payments, the remaining balance of any lease incentive received, unamortized initial direct costs, and any impairment of the right-of-use asset. The initial measurement of the lease liabilities and right-to-use assets of finance leases is the same as for operating leases.

Lease expense for operating leases is recognized on a straight-line basis over the lease term as part of our selling, general and administrative expenses and our research and development expenses on our consolidated statement of operations. Lease expense for financing leases consists of amortization of the right-of-use asset and interest on the lease liability as part of our research and development expenses on our consolidated statement of operations.

For transition leases, entities are permitted to make an election to apply a package of practical expedients that allows entities not to reassess (i) whether any expired or existing contracts are or contain leases, (ii) lease classification for any expired or existing leases, and (iii) whether initial direct costs for any expired or existing leases qualify for capitalization under ASC 842. These practical expedients must be elected as a package and must be consistently applied to all leases. In addition, entities are also permitted to make an election to use hindsight when determining lease terms and when assessing the impairment of right-of-use assets. We have chosen to elect the package of practical expedients but did not elect the hindsight practical expedient for our transition leases.

Adoption of the new standard resulted in the recognition of a right-to-use asset of $1.5 million, an operating lease liability of $2.2 million dollars, and a related decrease in deferred rent liability of $0.7 million at January 1, 2019.

Other Significant Accounting Policies

Our other significant accounting policies were reported in our Annual Report on Form 10-K for the year ended December 31, 2018 that was filed with the SEC on March 18, 2019. Our other significant accounting policies have not changed materially from the policies previously reported.

Recently Adopted Standards

In February 2016, the FASB issued ASU No. 2016-02, Leases (ASC 842). Under the new guidance, lessees are 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. We adopted this standard on January 1, 2019 and applied the practical expedients thereby continuing to account for leases that commenced before the effective date in accordance with previous GAAP. See note 1 – Significant Accounting Policies, and note 6 – Lease of our condensed consolidated financial statements, for further information.

In June 2018, the FASB issued ASU No. 2018-07, Compensation – Stock Compensation (ASC 718) – Improvements to Non-employee Share-Based Payment Accounting, which aligns the accounting for share-based payment awards issued to employees and nonemployees. Under ASU 2018-07, the existing employee guidance will apply to nonemployee share-based transactions (as long as the transaction is not effectively a form of financing), with the exception of specific guidance related to the attribution of compensation cost. The cost of nonemployee awards will continue to be recorded as if the grantor had paid cash for the goods or services. In addition, the contractual term will be used in lieu of an expected term in the option-pricing model for nonemployee awards. We adopted this on January 1, 2019, and there was no impact on our consolidated results of operations, financial position, and cash flows.

In August 2018, the SEC adopted amendments to certain disclosure requirements in Securities Act Release No. 33-10532, Disclosure Update and Simplification. Among the amendments is the requirement to present any changes in shareholders’ equity in the interim financial statements, either in a separate statement or footnote in the quarterly reports on Form 10-Q. The amendments became effective on November 5, 2018. We have included a separate statement, the Condensed Consolidated Statements of Changes in Stockholders’ Equity in this Quarterly Report on Form 10Q.

Collaboration Agreements

3 Months Ended

Mar. 31, 2019

Organization Consolidation And Presentation Of Financial Statements [Abstract]

Collaboration Agreements

Note 2. 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.

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.

We assessed the arrangement in accordance with ASC 606 and concluded that the contract counterparty, Alligator, is not a customer. As such the arrangement is not in the scope of ASC 606 and is instead treated as a collaborative agreement under ASC 808. For the three months ended March 31, 2019, we recorded a reduction in our research and development expense of $0.4 million and for the three months ended March 31, 2018, we recorded an increase in our research and development expense of less than $0.1 million related to the collaboration arrangement.

Fair Value Measurements

3 Months Ended

Mar. 31, 2019

Fair Value Disclosures [Abstract]

Fair Value Measurements

Note 3. 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.

At March 31, 2019 and December 31, 2018, we had $34.1 million and $29.0 million in money market funds, respectively.

The carrying amounts of our money market funds approximate their fair value. At March 31, 2019, we did not have any level two or level three assets.

- 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

Cash, Cash Equivalents, and Restricted Cash

3 Months Ended

Mar. 31, 2019

Cash And Cash Equivalents [Abstract]

Cash, Cash Equivalents, and Restricted Cash

Note 4. Cash, Cash Equivalents, and Restricted Cash

The Company’s 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. Restricted cash, long-term includes $5.0 million related to the minimum cash covenant included in the Company’s Credit and Security Agreement (the Credit Agreement) with MidCap Financial Trust, and $2.4 million securing letters of credit.

The following table shows our cash, cash equivalents and long-term restricted cash as of March 31, 2019 and December 31, 2018:

	March 31,		December 31,
(in thousands)	2019		2018
Cash	$	7,864	$	6,588
Cash equivalents		29,147		24,047
Restricted cash		7,448		7,448
Total cash, cash equivalents, and restricted cash	$	44,459	$	38,083

Inventories

3 Months Ended

Mar. 31, 2019

Inventory Disclosure [Abstract]

Inventories

Note 5. Inventories

Inventories consist of the following:

	March 31,		December 31,
(in thousands)	2019		2018
Raw materials and supplies	$	162	$	194
Work-in-process		4,023		916
Finished goods		161		675
Total inventories	$	4,346	$	1,785

Leases

3 Months Ended

Mar. 31, 2019

Leases [Abstract]

Leases

Note 6. Leases

Office Space Lease - Operating

In 2003, we entered into a lease for our corporate headquarters located in Seattle, Washington. This lease has been amended multiple times to add additional space and extend the lease term. Amendment number seven, became effective on September 1, 2014 and expires on April 30, 2020, covering 50,466 square feet of office, laboratory, and meeting space. We are required to pay a proportionate share of certain operating expenses as defined in the agreement with the lessor and a proportionate share of the real estate taxes as assessed. We received a tenant improvement allowance that was settled in June 2017 and which we elected to amortize as a reduction in rent over the remaining term of the lease. The lease has a two-year renewal option at fair market value on the date of renewal and a termination option by giving nine months’ notice and a penalty equal to the unamortized tenant improvement allowance, the unamortized real estate fee, and the market value of free parking. For the three months ended March 31, 2019, we recorded $0.4 million in lease expense, including $0.1 million for variable payments.

We recorded a right-of-use asset for this lease on January 1, 2019, of $1.2 million which reflects the amount of the remaining lease liability, less the balance of accrued and deferred rent, and net of the unamortized balance of tenant incentives. We also recorded a lease liability of $1.9 million which reflects the present value of the remaining lease payments, discounted using our incremental borrowing rate of 16.95% for the remaining term of the lease. The future expense for this lease will be recorded as a straight-line expense, less the unamortized tenant incentive portion, plus any variable expenses due to true-ups of operating costs or real estate taxes.

On March 19, 2019, we entered into a new lease amendment, number eight, for our current headquarters in Seattle, Washington. This amendment extended the terms of the lease for ten years, until April 30, 2030, and reduced the total square footage of our office space to 47,692 after May 1, 2020. We determined we should not include any periods after the termination option when evaluating this amendment as we are not reasonably certain to not exercise the option, therefore we are recording our liability through April 30, 2023. In March 2019, we recorded an increase to our right-of-use asset for this lease amendment of $3.2 million which reflects the amount of the remaining lease liability through April 30, 2023, less the balance of accrued and deferred rent, and net of the unamortized balance of tenant incentives. In March 2019, we also recorded an increase to our lease liability for this lease amendment of $3.2 million which reflects the present value of the remaining lease payments through April 30, 2023, discounted using our incremental borrowing rate of 14.45% for the remaining term of the lease on the date of amendment.

This new amendment has a renewal option of two five-year renewals at fair market value as determined at the time of renewal, and a termination option after month thirty-six with nine months written notice. The termination option also requires a penalty equal to the unamortized tenant improvement allowance at 8% interest, the unamortized real estate taxes at 8% interest, and the equivalent of four-months’ rent at the base rent price at the time of termination. The estimated termination penalty has been recorded in our lease payments.

Equipment Leases - Operating

As of January 1, 2019, we have operating leases for one piece of lab equipment and four copiers in our Seattle, Washington headquarters. We recorded a right-of-use asset of $0.3 million on January 1, 2019 which reflects the remaining liability of the leases, less the balance of accrued and deferred rent. We also recorded a lease liability of $0.3 million which reflects the present value of the remaining payment for the leases, discounted using our incremental borrowing rate for the lab equipment lease is 16.53% and for the copier leases it is 16.19%, for the remaining term of the leases. The future expense for these leases will be straight-line and will include any variable expenses that arise.

Equipment Lease – Financing

As of January 1, 2019, we had one equipment lease classified as a financing lease as the lease transfers ownership of the underlying asset to us at the end of the lease term. At the adoption of the standard at January 1, 2019, we did not make any additional reclassification for this lease as the entire carrying amount had already been recorded as a capital lease obligation under ASC 840 – Leases. The remaining term of this lease is seventeen months and has a remaining expense obligation of less than $0.1 million. There were no financing lease payments in the three months ended March 31, 2019.

Components of lease expense:

	For the Three Months Ended March 31,
(in thousands)	2019
Operating lease cost	$	335
Finance lease cost:
Amortization of right-of-use assets		1
Interest on lease liabilities		1
Total lease cost	$	337

Supplemental cash flows information related to leases is as follows:

Right of use assets acquired under operating leases:

	For the Three Months Ended March 31,
(in thousands)	2019
Operating leases, excluding Seattle office lease	$	345
Seattle office lease, including amendment		4,347
Total operating leases	$	4,692

Lease payments:

	For the Three Months Ended March 31,
(in thousands)	2019
For operating leases	$	434

Future minimum payments as of March 31, 2019 are as follows:

(in thousands)
9 months ended December 31, 2019	$	1,310
12 months ended December 31, 2020		1,510
12 months ended December 31, 2021		1,387
12 months ended December 31, 2022		1,294
12 months ended December 31, 2023		1,399
Total Future minimum lease payments		6,900
Less: imputed interest		(1,824	)
Total	$	5,076

The long-term portion of the lease liabilities included in the amounts above is $4.0 million and the remainder of our lease liabilities are included in other current liabilities on our condensed consolidated balance sheets.

As of March 31, 2019, the weighted average remaining lease term and weighted discount rate for operating leases was 4.0 years and 14.56%.

Debt

3 Months Ended

Mar. 31, 2019

Debt Disclosure [Abstract]

Debt

Note 7. Debt

Credit Facility

On August 4, 2016, we entered into a Credit and Security Agreement (Credit Agreement), with MidCap Financial Trust. The original Credit Agreement provided us with up to $35.0 million of available borrowing capacity composed of two tranches of $20.0 million and $15.0 million. The first tranche of $20.0 million was made available to us, and drawn, on the closing date of the Credit Agreement. On September 28, 2017, we and MidCap Financial Trust entered into a second amendment to the Credit Agreement in order to accommodate the sale of the Hyperimmune Business under the LLC purchase agreement, and to reflect changes in the remaining business as a result of such sale.

Pursuant to the second Amendment, the agent and the lenders consented to the LLC purchase agreement and the consummation of the sale transaction, released the agent’s liens on the assets transferred to one of our subsidiaries prior to the sale, and agreed that no prepayment of the term loans under the credit agreement would be required as a result the sale. As part of the second amendment, the agent and the lenders agreed that: (i) the commitments of the lenders to make the remaining $15.0 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 requiring us to maintain a minimum $10.0 million unrestricted cash balance, and (iv) the date on which the term loans begin to amortize would be extended to February 1, 2019 if we achieved net commercial product revenues of $16.0 million for the twelve month period ending June 30, 2018 and maintain such level of net commercial product revenues for each quarter prior to February 1, 2019 thereafter. As we achieved net commercial product revenues of $16.2 million for the twelve month period ending June 30, 2018, our principal repayments have been deferred to February 1, 2020.

On February 23, 2018, we entered into a third Amendment with the agent and lenders to amend certain provisions of the Credit Agreement in order to permit us to maintain a cash collateral account as security for our reimbursement obligations, in respect of certain letters of credit to be issued for our account.

On August 6, 2018, we entered into an Amended and Restated Credit and Security Agreement (Amended Credit Agreement) amending the terms of our original $20 million term loan agreement with MidCap. Under the Amended Credit Agreement, the timeline for us to begin making principal repayments has been extended to February 1, 2020, with an opportunity for further deferral through August 1, 2020. The amount of restricted cash that we are required to maintain on our balance sheet has been reduced from $10 million to $5 million.

In January 2019, our unrestricted cash level fell below $25.0 million which triggered the effectiveness of a security agreement in favor of MidCap with respect to our registered intellectual property to secure our obligations under the Amended Credit Agreement. MidCap now holds a security interest in our registered intellectual property and may take ownership of such intellectual property if we do not satisfy our obligations under the Amended Credit Agreement.

Additionally, this amendment is subject to a subjective acceleration clause, although we believe the likelihood of an acceleration of the due date for this obligation is remote.

The obligations under the Amended Credit Agreement will mature on February 1, 2023. Amounts drawn under the Amended Credit Agreement continue to accrue interest at a rate of LIBOR plus 7.60% per annum.

Net Loss Per Share

3 Months Ended

Mar. 31, 2019

Earnings Per Share [Abstract]

Net Loss Per Share

Note 8. Net Loss per Share

Basic net loss per share is calculated by dividing the net loss by the weighted average number of common shares outstanding for the period. Diluted net loss per share is computed by dividing the net 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, warrants, stock options and restricted stock units (RSUs) are only included in the calculation of diluted net income per share when their effect is dilutive.

Common stock equivalents include warrants, stock options and unvested RSUs.

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 Three Months Ended March 31,
(in thousands)	2019		2018
Warrants		22,000		—
Outstanding options to purchase common stock		4,100		3,472
Unvested RSUs		10		196

Equity

3 Months Ended

Mar. 31, 2019

Equity [Abstract]

Equity

Note 9. Equity

Common Stock

On March 11, 2019, we completed a public offering of common stock and warrants, as follows:

•

for a combined public offering price of $1.00 per share of common stock and related warrants, 19,850,000 shares of common stock and related warrants with a 5-year life to purchase up to 19,850,000 shares of common stock at an exercise price of $1.30 per share,

•

for a combined public offering price of $0.99 per pre-funded warrant and related warrant, pre-funded warrants with a 10-year life to purchase up to 2,150,000 shares of common stock at an exercise price of $0.01 per share and related warrants with a 5-year life to purchase up to 2,150,000 shares of common stock at an exercise price of $1.30 per share. These pre-funded warrants were exercised on March 21, 2019.

We received net proceeds of $20.2 million, net of transaction costs, as a result of this offering.

For the three months ended March 31, 2019, we issued 85,936 shares of common stock due to the vesting of RSUs. In addition, pursuant to our purchase agreement with Lincoln Park, we issued 195,867 of commitment shares in a non-cash transaction.

During the three months ended March 31, 2018, we received proceeds of $0.2 million upon the exercise of stock options which resulted in the issuance of 75,425 shares of common stock and issued 760,833 shares of common stock due to the vesting of restricted stock units.

Equity Distribution Agreement

On November 9, 2017, we entered into an Equity Distribution Agreement (the Equity Distribution Agreement) with Piper Jaffray & Co. (Piper Jaffray). The Equity Distribution Agreement provides that, upon the terms and subject to the conditions set forth therein, we may issue and sell through Piper Jaffray, acting as sales agent, shares of our common stock, $0.001 par value per share (the Common Stock) having an aggregate offering price of up to $17.5 million. We have no obligation to sell any such shares under the Equity Distribution Agreement. The sale of such shares of common stock by Piper Jaffray will be effected pursuant to a Registration Statement on Form S-3 which we filed on November 9, 2017. We issued 13,265 shares under the Equity Distribution Agreement in the fourth quarter of 2018, and no shares in the first quarter of 2019.

Converted Equity Awards Incentive Plan

In connection with the spin-off from Emergent BioSolutions, Inc. (Emergent) in August 2016, 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. 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 equity stock options.

Stock options under the 2016 SIP generally vest pro rata over a three-year period and terminate ten years from the grant date, though the specific terms of each grant are determined individually. The Company’s executive officers and certain other employees may be awarded options with different vesting criteria, and options granted to non-employee directors also vest over a three-year period. Option exercise prices for new options granted by the Company equal the closing price of the Company’s common stock on the Nasdaq Global Market on the date of grant.

RSUs issued under the 2016 SIP provide for the issuance of a share of the Company’s common stock at no cost to the holder. RSUs granted to employees under the 2016 SIP generally provide for time-based vesting over an eighteen-month to three-year period, although certain employees may be awarded RSUs with different time-based vesting criteria. Prior to vesting, RSUs granted under the 2016 SIP do not have dividend equivalent rights, do not have voting rights and the shares underlying the RSUs are not considered issued or outstanding.

The equity compensation awards granted by the Company generally vest only if the employee is employed by the Company (or in the case of directors, the director continues to serve on the Board) on the vesting date.

On May 31, 2017, at the 2017 Annual Meeting of Stockholders (Annual Meeting), the Company’s stockholders approved the amendment and restatement of the Company’s 2016 SIP (Restated 2016 Plan) to, among other things, increase the number of authorized shares issuable by 1.3 million shares of Aptevo common stock. The Restated 2016 Plan was previously approved, subject to stockholder approval, by the Board of Directors of the Company.

2018 Stock Incentive Plan

On June 1, 2018, at the 2018 Annual Meeting, the Company’s stockholders approved a new 2018 Stock Incentive Plan (2018 SIP), which replaces the Restated 2016 Plan on a go-forward basis. All stock options, RSUs or other equity awards granted subsequent to June 1, 2018 will be issued out of the 2018 SIP, which has 2.9 million shares of Aptevo common stock authorized for issuance. The 2018 Plan became effective immediately upon stockholder approval at the Annual Meeting. Any shares subject to outstanding stock awards granted under the 2016 SIP that (a) expire or terminate for any reason prior to exercise or settlement; (b) are forfeited because of the failure to meet a contingency or condition required to vest such shares or otherwise return to the Company; or (c) otherwise would have returned to the 2016 SIP for future grant pursuant to the terms of the 2016 Plan (such shares, the “Returning Shares”) will immediately be added to the share reserve under the 2018 SIP as and when such shares become Returning Shares, up to a maximum of 3,711,620 shares. The 2018 SIP was previously approved, subject to stockholder approval, by the Board of Directors of the Company. As of March 31, 2019, there are 2.0 million shares available to be granted under the 2018 SIP.

Stock options under the 2018 SIP generally vest pro rata over a three-year period and terminate ten years from the grant date, though the specific terms of each grant are determined individually. The Company’s executive officers and certain other employees may be awarded options with different vesting criteria, and options granted to non-employee directors also vest over a three-year period. Option exercise prices for new options granted by the Company equal the closing price of the Company’s common stock on the Nasdaq Global Market on the date of grant.

Stock-Based Compensation Expense

Stock-based compensation expense includes amortization of stock options and RSUs granted to employees and non-employees and has been reported in our Condensed Consolidated Statements of Operations as follows:

	For the Three Months Ended March 31,
(in thousands)	2019		2018
Research and development	$	251	$	327
Selling, general and administrative		343		390
Total stock-based compensation expense	$	594	$	717

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 Three Months Ended March 31,
	2019	2018
Expected dividend yield	0.00%	0.00%
Expected volatility	75.00%	75.00%
Risk-free interest rate	2.52%	2.72%
Expected average life of options	7 years	6 years

Management has applied an estimated forfeiture rate of 10% for the periods presented.

The following is a summary of option activity for the three months ended March 31, 2019:

	Number of Shares			Weighted- Average Exercise Price		Weighted- Average Remaining Term		Aggregate Intrinsic Value
Balance at December 31, 2018		3,329,618		$	2.74		—	$	—
Granted		821,523			1.60		—		—
Exercised		—			—		—		—
Forfeited		(50,670	)		2.42		—		—
Outstanding at March 31, 2019		4,100,471		$	2.51		7.31	$	—
Exercisable at March 31, 2019		2,062,402		$	2.56		5.59	$	—

As of March 31, 2019, we had $2.6 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 5.6 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 March 2019 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 the last trading day of the quarter. As of December 31, 2018, and March 31, 2019, we had no outstanding options with an exercise price below the trading price of our common stock.

Restricted Stock Units

The following is a summary of RSU activity for the three months ended March 31, 2019:

	Number of Units		Weighted Average Fair Value per Unit		Aggregate Fair Value
Balance at December 31, 2018		133,040	$	2.97	$	168,961
Vested		123,442		2.94		—
Forfeited		—		—		—
Outstanding at March 31, 2019		9,618	$	3.38	$	8,991
Expected to Vest		9,618	$	3.38	$	8,991

As of March 31, 2019, we had less than $0.1 million of unrecognized compensation expense related to RSU’s, which will all be fully vested by May 10, 2019.

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

Warrants

In March 2019, as part of a public offering, we issued warrants to purchase up to 24,150,000 shares of our common stock, 22,000,000 of which have an exercise price of $1.30 per share and have a five-year life, and 2,150,000 of pre-funded warrants with an exercise price of $0.01 per share. The pre-funded warrants have a ten-year life and expire on March 11, 2029. The warrants with a $0.01 per share exercise price were exercised in March 2019. We determined the warrants do not meet liability classification pursuant to ASC 480 – Distinguishing Liabilities from Equity. There are therefore included within equity on our consolidated balance sheet. As of March 31, 2019, there were 22,000,000 outstanding.

Revenue Reserves

3 Months Ended

Mar. 31, 2019

Revenue From Contract With Customer [Abstract]

Revenue Reserves

Note 10. Revenue Reserves

The following table summarizes activity in each of our product revenue allowance and reserve categories for the three months ending March 31, 2019:

(in thousands)	Chargebacks and Cash Discounts			Distribution Fees, Rebates and Patient Assistance
Balance at December 31, 2018	$	(1,323	)	$	(865	)
Provision related to current period sales		(704	)		(923	)
Credit or payments made during the period		922			931
Balance at March 31, 2019	$	(1,105	)	$	(857	)

Nature of Business and Significant Accounting Policies (Policies)	3 Months Ended
	Mar. 31, 2019
Accounting Policies [Abstract]
Leases	Leases On January 1, 2019 we adopted ASU No. 2016-02, Leases (ASC 842), which amends the existing standards for lease accounting, requiring lessees to recognize most leases on their balance sheets and disclose key information about leasing arrangements. We adopted the new standard using a modified retrospective transition approach for the leases at the beginning of the current fiscal year, January 1, 2019. We did not adjust comparative periods in our financial statements prior to that period. See note 6 – Leases, of our condensed consolidated financial statements for additional information. The new standard establishes a right-of-use model that requires a lessee to recognize an operating lease right-of-use asset and lease liability on the balance sheet for all leases with a term longer than twelve months. Leases are to be classified as finance or operating at the lease commencement, which affects the classification of expense recognition in the income statement. Right-of-use assets represent the right to use an underlying asset for the lease term and lease liabilities represent the obligation to make lease payments, as agreed to in the lease. Operating lease liabilities are recognized at the date of lease commencement based on the present value of lease payments over the lease term. As leases may include options to extend the lease period, or options for early termination, when it is reasonably certain that an entity is going to exercise the renewal option, the additional payments are to be included in the lease’s terms. When it is reasonably certain that an early termination option will not be exercised, the lease’s terms are to be extended beyond the possible early termination date or dates. The standard requires that we use our incremental borrowing rate (IBR) as the discount rate in our lease evaluation if a rate implicit in the lease cannot be identified. Due to the significant judgment involved and the complex analysis needed to determine this discount rate, we engaged a third-party valuation specialist to advise us in our determination of our IBR. An operating right-of-use asset is measured as the amount of the initial measurement of the lease liability, adjusted for prepaid or accrued lease payments, the remaining balance of any lease incentive received, unamortized initial direct costs, and any impairment of the right-of-use asset. The initial measurement of the lease liabilities and right-to-use assets of finance leases is the same as for operating leases. Lease expense for operating leases is recognized on a straight-line basis over the lease term as part of our selling, general and administrative expenses and our research and development expenses on our consolidated statement of operations. Lease expense for financing leases consists of amortization of the right-of-use asset and interest on the lease liability as part of our research and development expenses on our consolidated statement of operations. For transition leases, entities are permitted to make an election to apply a package of practical expedients that allows entities not to reassess (i) whether any expired or existing contracts are or contain leases, (ii) lease classification for any expired or existing leases, and (iii) whether initial direct costs for any expired or existing leases qualify for capitalization under ASC 842. These practical expedients must be elected as a package and must be consistently applied to all leases. In addition, entities are also permitted to make an election to use hindsight when determining lease terms and when assessing the impairment of right-of-use assets. We have chosen to elect the package of practical expedients but did not elect the hindsight practical expedient for our transition leases. Adoption of the new standard resulted in the recognition of a right-to-use asset of $1.5 million, an operating lease liability of $2.2 million dollars, and a related decrease in deferred rent liability of $0.7 million at January 1, 2019.
Other Significant Accounting Policies	Other Significant Accounting Policies Our other significant accounting policies were reported in our Annual Report on Form 10-K for the year ended December 31, 2018 that was filed with the SEC on March 18, 2019. Our other significant accounting policies have not changed materially from the policies previously reported.
Recently Adopted Standards	Recently Adopted Standards In February 2016, the FASB issued ASU No. 2016-02, Leases (ASC 842). Under the new guidance, lessees are 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. We adopted this standard on January 1, 2019 and applied the practical expedients thereby continuing to account for leases that commenced before the effective date in accordance with previous GAAP. See note 1 – Significant Accounting Policies, and note 6 – Lease of our condensed consolidated financial statements, for further information. In June 2018, the FASB issued ASU No. 2018-07, Compensation – Stock Compensation (ASC 718) – Improvements to Non-employee Share-Based Payment Accounting, which aligns the accounting for share-based payment awards issued to employees and nonemployees. Under ASU 2018-07, the existing employee guidance will apply to nonemployee share-based transactions (as long as the transaction is not effectively a form of financing), with the exception of specific guidance related to the attribution of compensation cost. The cost of nonemployee awards will continue to be recorded as if the grantor had paid cash for the goods or services. In addition, the contractual term will be used in lieu of an expected term in the option-pricing model for nonemployee awards. We adopted this on January 1, 2019, and there was no impact on our consolidated results of operations, financial position, and cash flows. In August 2018, the SEC adopted amendments to certain disclosure requirements in Securities Act Release No. 33-10532, Disclosure Update and Simplification. Among the amendments is the requirement to present any changes in shareholders’ equity in the interim financial statements, either in a separate statement or footnote in the quarterly reports on Form 10-Q. The amendments became effective on November 5, 2018. We have included a separate statement, the Condensed Consolidated Statements of Changes in Stockholders’ Equity in this Quarterly Report on Form 10Q.

Cash, Cash Equivalents, and Restricted Cash (Tables)

3 Months Ended

Mar. 31, 2019

Cash And Cash Equivalents [Abstract]

Schedule of Cash, Cash Equivalents and Long-term Restricted Cash

The following table shows our cash, cash equivalents and long-term restricted cash as of March 31, 2019 and December 31, 2018:

	March 31,		December 31,
(in thousands)	2019		2018
Cash	$	7,864	$	6,588
Cash equivalents		29,147		24,047
Restricted cash		7,448		7,448
Total cash, cash equivalents, and restricted cash	$	44,459	$	38,083

Inventories (Tables)

3 Months Ended

Mar. 31, 2019

Inventory Disclosure [Abstract]

Schedule of Inventories

Inventories consist of the following:

	March 31,		December 31,
(in thousands)	2019		2018
Raw materials and supplies	$	162	$	194
Work-in-process		4,023		916
Finished goods		161		675
Total inventories	$	4,346	$	1,785

Leases (Tables)

3 Months Ended

Mar. 31, 2019

Leases [Abstract]

Components of Lease Expense

Components of lease expense:

	For the Three Months Ended March 31,
(in thousands)	2019
Operating lease cost	$	335
Finance lease cost:
Amortization of right-of-use assets		1
Interest on lease liabilities		1
Total lease cost	$	337

Summary of Supplemental Cash Flows Information Related to Leases

Supplemental cash flows information related to leases is as follows:

Right of use assets acquired under operating leases:

	For the Three Months Ended March 31,
(in thousands)	2019
Operating leases, excluding Seattle office lease	$	345
Seattle office lease, including amendment		4,347
Total operating leases	$	4,692

Lease payments:

	For the Three Months Ended March 31,
(in thousands)	2019
For operating leases	$	434

Summary of Future Minimum Lease Payments

Future minimum payments as of March 31, 2019 are as follows:

(in thousands)
9 months ended December 31, 2019	$	1,310
12 months ended December 31, 2020		1,510
12 months ended December 31, 2021		1,387
12 months ended December 31, 2022		1,294
12 months ended December 31, 2023		1,399
Total Future minimum lease payments		6,900
Less: imputed interest		(1,824	)
Total	$	5,076

Net Loss Per Share (Tables)

3 Months Ended

Mar. 31, 2019

Earnings Per Share [Abstract]

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 Three Months Ended March 31,
(in thousands)	2019		2018
Warrants		22,000		—
Outstanding options to purchase common stock		4,100		3,472
Unvested RSUs		10		196

Equity (Tables)

3 Months Ended

Mar. 31, 2019

Equity [Abstract]

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

	For the Three Months Ended March 31,
(in thousands)	2019		2018
Research and development	$	251	$	327
Selling, general and administrative		343		390
Total stock-based compensation expense	$	594	$	717

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 Three Months Ended March 31,
	2019	2018
Expected dividend yield	0.00%	0.00%
Expected volatility	75.00%	75.00%
Risk-free interest rate	2.52%	2.72%
Expected average life of options	7 years	6 years

Summary of Stock Option Activity

The following is a summary of option activity for the three months ended March 31, 2019:

	Number of Shares			Weighted- Average Exercise Price		Weighted- Average Remaining Term		Aggregate Intrinsic Value
Balance at December 31, 2018		3,329,618		$	2.74		—	$	—
Granted		821,523			1.60		—		—
Exercised		—			—		—		—
Forfeited		(50,670	)		2.42		—		—
Outstanding at March 31, 2019		4,100,471		$	2.51		7.31	$	—
Exercisable at March 31, 2019		2,062,402		$	2.56		5.59	$	—

Summary of RSU Activity

The following is a summary of RSU activity for the three months ended March 31, 2019:

	Number of Units		Weighted Average Fair Value per Unit		Aggregate Fair Value
Balance at December 31, 2018		133,040	$	2.97	$	168,961
Vested		123,442		2.94		—
Forfeited		—		—		—
Outstanding at March 31, 2019		9,618	$	3.38	$	8,991
Expected to Vest		9,618	$	3.38	$	8,991

Revenue Reserves (Tables)

3 Months Ended

Mar. 31, 2019

Revenue From Contract With Customer [Abstract]

Summary of Product Revenue Allowance and Reserve Categories

The following table summarizes activity in each of our product revenue allowance and reserve categories for the three months ending March 31, 2019:

(in thousands)	Chargebacks and Cash Discounts			Distribution Fees, Rebates and Patient Assistance
Balance at December 31, 2018	$	(1,323	)	$	(865	)
Provision related to current period sales		(704	)		(923	)
Credit or payments made during the period		922			931
Balance at March 31, 2019	$	(1,105	)	$	(857	)

Nature of Business and Significant Accounting Policies - Additional Information (Details) $ / shares in Units, $ in Thousands			1 Months Ended	3 Months Ended
	Mar. 11, 2019 $ / shares shares	Jan. 01, 2019 USD ($)	Mar. 31, 2019 USD ($) $ / shares shares	Mar. 31, 2019 USD ($) Product $ / shares shares
Nature Of Business [Line Items]
Number of revenue-generating product \| Product				1
Warrants exercise price, per share \| $ / shares			$ 1.30	$ 1.30
Pre funded warrants exercise price, per share \| $ / shares			$ 0.01
Proceeds from issuance of warrants				$ 20,200
Warrants outstanding, term			10 years	10 years
Operating lease right-of-use asset			$ 4,481	$ 4,481
Operating lease liability			$ 5,076	5,076
ASU No. 2016-02
Nature Of Business [Line Items]
Operating lease right-of-use asset		$ 1,500
Operating lease liability		2,200
Decrease in deferred rent liability		$ 700
Common Stock
Nature Of Business [Line Items]
Number of shares issued \| shares			19,850,000
Warrants exercise price, per share \| $ / shares	$ 1.30
Issuance of pre-funded warrants \| shares			2,150,000
Pre funded warrants exercise price, per share \| $ / shares	$ 0.01
Proceeds from issuance of warrants				20,200
Warrants outstanding, term	5 years
Maximum
Nature Of Business [Line Items]
Additional proceeds to be received upon exercise of the warrants			$ 28,600	28,600
Operating lease right-of-use asset			300	300
Operating lease liability			$ 300	$ 300
Maximum \| Common Stock
Nature Of Business [Line Items]
Number of common stock to be issued up conversion of warrants \| shares	19,850,000		19,850,000	19,850,000
Number of common stock to be issued exercise of prefunded warrants \| shares	2,150,000		2,150,000

Collaboration Agreements - Additional Information (Details) - USD ($)	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Reduction in research and development expense	$ 400,000	$ 400,000
Maximum
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Increase in research and development expense.	$ 100,000

Fair Value Measurements - Additional Information (Details) - USD ($)	Mar. 31, 2019	Dec. 31, 2018
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Money market funds	$ 34,100,000	$ 29,000,000
Level Two
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Fair value assets	0
Level Three
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Fair value assets	$ 0

Cash, Cash Equivalents and Restricted Cash - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Restricted Cash And Cash Equivalents Items [Line Items]
Long-term restricted cash	$ 7,448	$ 7,448	$ 10,000
Maximum
Restricted Cash And Cash Equivalents Items [Line Items]
Cash equivalents, maturity period	90 days
Letter of Credit
Restricted Cash And Cash Equivalents Items [Line Items]
Long-term restricted cash	$ 2,400
Covenant of MidCap Loan Agreement
Restricted Cash And Cash Equivalents Items [Line Items]
Long-term restricted cash	$ 5,000

Cash, Cash Equivalents and Restricted Cash - Schedule of Cash, Cash Equivalents and Long-term Restricted Cash (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Cash And Cash Equivalents [Abstract]
Cash	$ 7,864	$ 6,588
Cash equivalents	29,147	24,047
Restricted cash	7,448	7,448	$ 10,000
Total cash, cash equivalents, and restricted cash	$ 44,459	$ 38,083

Inventories - Schedule of Inventories (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Inventory Adjustments [Abstract]
Raw materials and supplies	$ 162	$ 194
Work-in-process	4,023	916
Finished goods	161	675
Total inventories	$ 4,346	$ 1,785

Leases - Additional Information (Details)			1 Months Ended		3 Months Ended
Leases - Additional Information (Details)	Mar. 19, 2019 ft² RenewalOption	Jan. 01, 2019 USD ($) Piece Copier Equipment	Mar. 31, 2019 USD ($)	Dec. 31, 2003 ft²	Mar. 31, 2019 USD ($)
Lessee Lease Description [Line Items]
Lease expense					$ 337,000
Operating lease right-of-use asset			$ 4,481,000		4,481,000
Operating lease liability			5,076,000		$ 5,076,000
Operating lease number of piece for lab equipment \| Piece		1
Operating lease number of copiers \| Copier		4
Financing lease number of equipment \| Equipment		1
Financing lease remaining term					17 months
Financing lease remaining expense obligation					$ 1,000
Financing lease payments					0
Long term portion of operating lease liabilities			$ 3,995,000		$ 3,995,000
Weighted average remaining lease term for operating leases			4 years		4 years
Weighted discount rate for operating leases			14.56%		14.56%
Maximum
Lessee Lease Description [Line Items]
Operating lease right-of-use asset			$ 300,000		$ 300,000
Operating lease liability			$ 300,000		300,000
Minimum
Lessee Lease Description [Line Items]
Financing lease remaining expense obligation					$ 100,000
Lab Equipment Lease
Lessee Lease Description [Line Items]
Operating lease, discounted incremental borrowing rate			16.53%		16.53%
Copier Leases
Lessee Lease Description [Line Items]
Operating lease, discounted incremental borrowing rate			16.19%		16.19%
Amendment Seven Operating lease \| Office Space Lease
Lessee Lease Description [Line Items]
Operating lease expiration amendment date				Apr. 30, 2020
Operating lease effective amendment date				Sep. 01, 2014
Operating lease square feet \| ft²				50,466
Operating lease renewal option description				The lease has a two-year renewal option at fair market value on the date of renewal
Operating lease renewal option to terminate description				a termination option by giving nine months’ notice and a penalty equal to the unamortized tenant improvement allowance, the unamortized real estate fee, and the market value of free parking.
Operating lease renewal option term				2 years
Operating lease termination option written notice period	9 months			9 months
Operating lease option to extend				true
Operating lease renewal option to terminate				true
Lease expense					$ 400,000
Variable payments					100,000
Operating lease right-of-use asset		$ 1,200,000
Operating lease liability			$ 1,900,000		$ 1,900,000
Operating lease, discounted incremental borrowing rate	14.45%		16.95%		16.95%
Number of operating lease renewal option \| RenewalOption	2
Operating lease termination option unamortized tenant improvement allowance interest rate	8.00%
Operating lease termination option unamortized real estate taxes interest rate	8.00%
Amendment Seven Operating lease \| Office Space Lease \| Renewal Option Two
Lessee Lease Description [Line Items]
Operating lease renewal option term			5 years		5 years
Amendment Seven Operating lease \| Office Space Lease \| Maximum
Lessee Lease Description [Line Items]
Operating lease right-of-use asset			$ 3,200,000
Operating lease liability			$ 3,200,000
Amendment Eight Operating lease \| Office Space Lease
Lessee Lease Description [Line Items]
Operating lease renewal option description	This amendment extended the terms of the lease for ten years, until April 30, 2030, and reduced the total square footage of our office space to 47,692 after May 1, 2020.
Operating lease renewal option to terminate description	We determined we should not include any periods after the termination option when evaluating this amendment as we are not reasonably certain to not exercise the option, therefore we are recording our liability through April 30, 2023
Operating lease renewal option term	10 years
Operating lease option to extend	true
Operating lease renewal option to terminate	true
Operating lease extended renewal option date	Apr. 30, 2030
Amendment Eight Operating lease \| Office Space Lease \| Minimum
Lessee Lease Description [Line Items]
Operating lease square feet \| ft²	47,692

Leases - Components of Lease Expense (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2019 USD ($)
Leases [Abstract]
Operating lease cost	$ 335
Finance lease cost:
Amortization of right-of-use assets	1
Interest on lease liabilities	1
Total lease cost	$ 337

Leases - Summary of Supplemental Cash Flows Information Related to Leases (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2019 USD ($)
Lessee Lease Description [Line Items]
Total operating leases	$ 4,692
For operating leases	434
Operating Leases, Excluding Seattle Office Lease
Lessee Lease Description [Line Items]
Total operating leases	345
Seattle Office Lease, Including Amendment
Lessee Lease Description [Line Items]
Total operating leases	$ 4,347

Leases - Summary of Future Minimum Lease Payments (Details) $ in Thousands	Mar. 31, 2019 USD ($)
Leases [Abstract]
9 months ended December 31, 2019	$ 1,310
12 months ended December 31, 2020	1,510
12 months ended December 31, 2021	1,387
12 months ended December 31, 2022	1,294
12 months ended December 31, 2023	1,399
Total Future minimum lease payments	6,900
Less: imputed interest	(1,824)
Total	$ 5,076

Debt - Additional Information (Details) - USD ($)			3 Months Ended		12 Months Ended
Debt - Additional Information (Details) - USD ($)	Aug. 06, 2018	Sep. 28, 2017	Mar. 31, 2019	Mar. 31, 2018	Jun. 30, 2018	Jan. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Aug. 04, 2016
Line Of Credit Facility [Line Items]
Maximum borrowing capacity									$ 35,000,000
Unrestricted cash balance			$ 7,864,000				$ 6,588,000
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 would be extended to February 1, 2019 if we achieved net commercial product revenues of $16.0 million for the twelve month period ending June 30, 2018 and maintain such level of net commercial product revenues for each quarter prior to February 1, 2019 thereafter
Revenue			$ 7,022,000	$ 4,071,000
Type of Revenue [Extensible List]			us-gaap:ProductMember	us-gaap:ProductMember
Long-term restricted cash			$ 7,448,000				$ 7,448,000	$ 10,000,000
Amended Credit Agreement
Line Of Credit Facility [Line Items]
Maximum borrowing capacity	$ 20,000,000
Line of credit, repayment begin date	Feb. 01, 2020
Line of credit, repayment deferral begin date	Aug. 01, 2020
Long-term restricted cash	$ 5,000,000
Credit agreement, maturity date	Feb. 01, 2023
Credit agreement reference rate for the variable rate			LIBOR
Credit agreement basis spread on variable rate	7.60%
Maximum \| Amended Credit Agreement
Line Of Credit Facility [Line Items]
Unrestricted cash balance						$ 25,000,000
Credit Facility First Tranche
Line Of Credit Facility [Line Items]
Maximum borrowing capacity									20,000,000
Credit facility available and drawn									20,000,000
Credit Facility Second Tranche
Line Of Credit Facility [Line Items]
Maximum borrowing capacity									$ 15,000,000
Prepayment of term loans		$ 0
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 required to be achieved on trailing twelve month basis		$ 16,000,000
Revenue					$ 16,200,000
Type of Revenue [Extensible List]					apvo:NetCommercialProductMember
Principal repayments date deferred upon achievement of net commercial product revenues			Feb. 01, 2020
Credit Facility Second Tranche \| Minimum
Line Of Credit Facility [Line Items]
Unrestricted cash balance		$ 10,000,000

Net Loss Per Share - Summary of Potentially Dilutive Shares Excluded from Calculation of Net Loss Per Share (Details) - shares shares in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Warrants
Schedule Of Earnings Per Share Basic And Diluted [Line Items]
Anti-dilutive shares excluded from calculation of diluted net loss per share	22,000
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	4,100	3,472
Unvested RSUs
Schedule Of Earnings Per Share Basic And Diluted [Line Items]
Anti-dilutive shares excluded from calculation of diluted net loss per share	10	196

Equity - Additional Information (Details) - USD ($)					1 Months Ended	3 Months Ended
Equity - Additional Information (Details) - USD ($)	Mar. 11, 2019	Jun. 01, 2018	Nov. 09, 2017	Aug. 01, 2016	Mar. 31, 2019	Mar. 31, 2019	Dec. 31, 2018	Mar. 31, 2018	May 31, 2017
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Warrants outstanding, term					10 years	10 years
Warrants exercise price, per share					$ 1.30	$ 1.30
Pre funded warrants outstanding, term					10 years
Pre funded warrants exercise price, per share					$ 0.01
Proceeds from issuance of warrants						$ 20,200,000
Proceeds upon exercise of stock options								$ 186,000
Common stock, par value					$ 0.001	$ 0.001	$ 0.001
Number of shares, outstanding					0	0
Pre funded warrants expire date					Mar. 11, 2029
RSUs
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period						May 10, 2019
Stock Option
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Estimated forfeiture rate						10.00%
Unrecognized compensation expense					$ 2,600,000	$ 2,600,000
Options expected to vest, weighted average period						2 years
Options outstanding and exercisable weighted average remaining contractual life						5 years 7 months 6 days
Number of shares, outstanding					4,100,471	4,100,471	3,329,618
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
Stock plan vesting period				3 years
Stock plan termination period				10 years
2016 Stock Incentive Plan \| RSUs
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Increase of authorized shares issuable									1,300,000
2016 Stock Incentive Plan \| Non-employee Directors
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock plan vesting period				3 years
2018 Stock Incentive Plan \| RSUs
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock authorized for issuance under Stock Plan		2,900,000
Stock plan vesting period		3 years
Stock plan termination period		10 years
Maximum number of returning shares from old plan to be add to shares reserve		3,711,620
Number of shares available for grant					2,000,000	2,000,000
2018 Stock Incentive Plan \| Non-employee Directors \| RSUs
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock plan vesting period		3 years
Equity Distribution Agreement
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock, par value			$ 0.001
Issuance of common stock shares						0	13,265
Tranche Two
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of common stock to be issued exercise of prefunded warrants					2,150,000
Pre funded warrants exercise price, per share					$ 0.01
Common Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares issued price per share	$ 1.00
Number of warrants issued	19,850,000
Warrants outstanding, term	5 years
Warrants exercise price, per share	$ 1.30
Pre funded warrant issued price, per share	$ 0.99
Pre funded warrants outstanding, term	10 years
Pre funded warrants exercise price, per share	$ 0.01
Proceeds from issuance of warrants						$ 20,200,000
Common stock issued upon vesting of restricted stock units (in shares)						85,936		760,833
Issuance of commitment shares of common stock, non-cash transaction (in shares)						195,867
Proceeds upon exercise of stock options								$ 200,000
Common stock issued upon exercise of stock options								75,425
Common stock issued upon vesting of restricted stock units								760,833
Issuance of common stock shares					19,850,000
Common Stock \| Converted Equity Awards Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock authorized for issuance under Stock Plan				1,300,000
Common Stock \| Tranche One
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Warrants outstanding, term	5 years
Warrants exercise price, per share	$ 1.30
Warrants
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Warrants outstanding, term					5 years	5 years
Warrants outstanding					22,000,000	22,000,000
Warrants \| Tranche One
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of warrants issued					22,000,000
Warrants exercise price, per share					$ 1.30	$ 1.30
Minimum \| 2016 Stock Incentive Plan \| RSUs
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock plan vesting period				18 months
Maximum \| RSUs
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unrecognized compensation expense					$ 100,000	$ 100,000
Maximum \| 2016 Stock Incentive Plan \| RSUs
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock plan vesting period				3 years
Maximum \| Common Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of common stock to be issued up conversion of warrants	19,850,000				19,850,000	19,850,000
Number of common stock to be issued exercise of prefunded warrants	2,150,000				2,150,000
Maximum \| Common Stock \| Equity Distribution Agreement
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Aggregate offering price			$ 17,500,000
Maximum \| Common Stock \| Tranche One
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of common stock to be issued up conversion of warrants	2,150,000
Maximum \| Warrants
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of common stock to be issued up conversion of warrants					24,150,000	24,150,000

Equity - Summary of Stock-based Compensation Expense Includes Amortization of Stock Options and Restricted Stock Units Granted (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense	$ 594	$ 717
Research and Development
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense	251	327
Selling, General and Administrative
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense	$ 343	$ 390

Equity - Assumptions used in Valuing the Stock Options Granted under Black-Scholes Valuation Model (Details) - Stock Option	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
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	2.52%	2.72%
Expected average life of options	7 years	6 years

Equity - Summary of Stock Option Activity (Details)	3 Months Ended
Equity - Summary of Stock Option Activity (Details)	Mar. 31, 2019 $ / shares shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of Shares, Outstanding, Ending balance	0
Stock Option
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of Shares, Outstanding, Beginning balance	3,329,618
Number of Shares, Granted	821,523
Number of Shares, Forfeited	(50,670)
Number of Shares, Outstanding, Ending balance	4,100,471
Number of Shares, Exercisable	2,062,402
Weighted-Average Exercise Price, Outstanding, Beginning balance \| $ / shares	$ 2.74
Weighted-Average Exercise Price, Granted \| $ / shares	1.60
Weighted-Average Exercise Price, Forfeited \| $ / shares	2.42
Weighted-Average Exercise Price, Outstanding, Ending balance \| $ / shares	2.51
Weighted-Average Exercise Price, Exercisable \| $ / shares	$ 2.56
Weighted-Average Remaining Term, Outstanding	7 years 3 months 21 days
Weighted-Average Remaining Term, Exercisable	5 years 7 months 2 days

Equity - Summary of Restricted Stock Activity (Details) - RSUs	3 Months Ended
	Mar. 31, 2019 USD ($) $ / shares shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of Units, Outstanding, Beginning balance \| shares	133,040
Number of Units, Vested \| shares	123,442
Number of Units, Outstanding, Ending balance \| shares	9,618
Number of Units, Expected to Vest \| shares	9,618
Weighted Average Fair Value per Unit, Outstanding Beginning Balance \| $ / shares	$ 2.97
Weighted Average Fair Value per Unit, Vested \| $ / shares	2.94
Weighted Average Fair Value per Unit, Outstanding Ending Balance \| $ / shares	3.38
Weighted Average Fair Value per Unit, Expected to Vest \| $ / shares	$ 3.38
Aggregate Fair Value, Outstanding, Beginning balance \| $	$ 168,961
Aggregate Fair Value, Outstanding, Ending balance \| $	8,991
Aggregate Fair Value, Expected to Vest \| $	$ 8,991

Revenue Reserves - Summary of Product Revenue Allowance and Reserve Categories (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2019 USD ($)
Chargebacks and Cash Discount
Valuation And Qualifying Accounts Disclosure [Line Items]
Beginning balance	$ (1,323)
Provision related to current period sales	(704)
Credit or payments made during the period	922
Ending balance	(1,105)
Distribution Fees, Rebates and Patient Assistance
Valuation And Qualifying Accounts Disclosure [Line Items]
Beginning balance	(865)
Provision related to current period sales	(923)
Credit or payments made during the period	931
Ending balance	$ (857)