This report includes “forward-looking statements” within the meaning of Section 27A of the Securities Act of 1933, as amended (Securities Act), and Section 21E of the Securities Exchange Act of 1934, as amended (Exchange Act). All statements other than statements of historical fact are “forward-looking statements” for purposes of this quarterly reportQuarterly Report on Form 10-Q, including any projections of market size, earnings, revenue, milestone payments, royalties, sales or other financial items, any statements of the plans and objectives of management for future operations (including, but not limited to, preclinical development, clinical trials and manufacturing), any statements related to our financial condition and future working capital needs, any statements regarding potential future financing alternatives, any statements concerning proposed drug candidates, any statements regarding the timing for the start or end of clinical trials or submission of regulatory approval filings, any statements regarding future economic conditions or performance, any statements regarding the initiation, formation, or success of our collaboration arrangements, timing of commercial launches and product sales levels by our collaboration partners and future payments that may come due to us under these arrangements, any statements regarding our plans and objectives to initiate or continue clinical trials, any statements related to potential, anticipated, or ongoing litigation, any statements concerning estimates and predictions of the COVID-19 pandemic's impact on our business and clinical trials and any statements of assumptions underlying any of the foregoing. In some cases, forward-looking statements can be identified by the use of terminology such as “believe,” “may,” “will,” “expects,” “plans,” “anticipates,” “estimates,” “potential” or “continue,” or the negative thereof or other comparable terminology. Although we believe that the expectations reflected in the forward-looking statements contained herein are reasonable, such expectations or any of the forward-looking statements may prove to be incorrect and actual results could differ materially from those projected or assumed in the forward-looking statements. Our future financial condition and results of operations, as well as any forward-looking statements, are subject to inherent risks and uncertainties, including, but not limited to, the risk factors set forth in Part II, Item 1A “Risk Factors” below and for the reasons described elsewhere in this quarterly reportQuarterly Report on Form 10-Q. All forward-looking statements and reasons why results may differ included in this report are made as of the date hereof and we do not intend to update any forward-looking statements except as required by law or applicable regulations. Except where the context otherwise requires, in this quarterly reportQuarterly Report on Form 10-Q, the terms “Company,” “Nektar,” “we,” “us,” and “our” refer to Nektar Therapeutics, a Delaware corporation, and, where appropriate, its subsidiaries.

Trademarks

Summary of Risks

We are providing the following cautionary discussion of risk factors, uncertainties and assumptions that we believe are relevant to our business. These are factors that, individually or in the aggregate, we think could cause our actual results to differ materially from expected and historical results and our forward-looking statements. We note these factors for investors as permitted by Section 21E of the Exchange Act and Section 27A of the Securities Act. Investors in Nektar Therapeutics should carefully consider the risks described below before making an investment decision. You should understand that it is not possible to predict or identify all such factors. Consequently, you should not consider this section to be a complete discussion of all potential risks or uncertainties that may substantially impact our business. Moreover, we operate in a competitive and rapidly changing environment. New factors emerge from time to time and it is not possible to predict the impact of all of these factors on our business, financial condition or results of operations.

Note 1 — Organization and Summary of Significant Accounting Policies

We are a research-based biopharmaceutical company headquartered in San Francisco, California and incorporated in Delaware. We are developing a pipeline of drug candidates that leverage our proprietary and proven advanced polymer conjugate technology platforms, which are designed to enable the development of new molecular entities that target known mechanisms of action. Our research and development pipeline of new investigational drugs includes potential therapies for oncology, immunology and virology.

Our research and development activities have required significant ongoing investment to date and are expected to continue to require significant investment. As a result, we expect to continue to incur substantial losses and negative cash flows from operations in the future. We have financed our operations primarily through cash generated from licensing, collaboration and manufacturing agreements and financing transactions. At March 31,June 30, 2021, we had approximately $1.1 billion in cash and investments in marketable securities.

Basis of Presentation and Principles of Consolidation

Our Condensed Consolidated Financial Statements include the financial position, results of operations and cash flows of our wholly-owned subsidiaries: Inheris Biopharma, Inc. (Inheris), Nektar Therapeutics (India) Private Limited (Nektar India), Nektar Therapeutics UK Limited,Europe GmbH, and Nektar Therapeutics NL B.V.certain other entities in Europe. We have eliminated all intercompany accounts and transactions in consolidation.

We prepared our Condensed Consolidated Financial Statements following the requirements of the Securities and Exchange Commission (SEC) for interim reporting. As permitted under those rules, we may condense or omit certain footnotes or other financial information that are normally required by U.S. generally accepted accounting principles (GAAP) for annual periods. In the opinion of management, these financial statements include all normal and recurring adjustments that we consider necessary for the fair presentation of our financial position and operating results.

Our Condensed Consolidated Financial Statements are denominated in U.S. dollars. Accordingly, changes in exchange rates between the applicable foreign currency and the U.S. dollar will affect the translation of each foreign subsidiary’s financial results into U.S. dollars for purposes of reporting our consolidated financial results. We include translation gains and losses in accumulated other comprehensive income (loss) in the stockholders’ equity section of our Condensed Consolidated Balance Sheets. To date, such cumulative currency translation adjustments have not been significant to our consolidated financial position.

Our comprehensive loss consists of our net loss plus our foreign currency translation gains and losses and unrealized holding gains and losses on available-for-sale securities. There were no significant reclassifications out of accumulated other comprehensive loss to the statements of operations during the three and six months ended March 31,June 30, 2021 and 2020.

The accompanying Condensed Consolidated Financial Statements are unaudited. The Condensed Consolidated Balance Sheet data as of December 31, 2020 was derived from the audited consolidated financial statements which are included in our Annual Report on Form 10-K for the year ended December 31, 2020 filed with the SEC on February 26, 2021. The information included in this Quarterly Report on Form 10-Q should be read in conjunction with the consolidated financial statements and the accompanying notes to those financial statements included in our Annual Report on Form 10-K for the year ended December 31, 2020.

Revenue, expenses, assets, and liabilities can vary during each quarter of the year. The results and trends in these interim Condensed Consolidated Financial Statements are not necessarily indicative of the results to be expected for the full year or any other period.

The preparation of consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the

date of the consolidated financial statements and the reported amounts of revenue and expenses during the reporting period. Accounting estimates and assumptions are inherently uncertain.

Actual results could differ materially from those estimates and assumptions. As appropriate, we assess our estimates each period, update them to reflect current information and generally recognize any changes in such estimates in the period first identified.

Reclassifications

Certain items previously reported in specific financial statement captions have been reclassified to conform to the current period presentation. Such reclassifications do not materially impact previously reported revenue, operating loss, net loss, total assets, liabilities or stockholders’ equity.

Segment Information

We operate in 1 business segment which focuses on applying our technology platform to develop novel drug candidates. Our business offerings have similar economics and other characteristics, including the nature of products and manufacturing processes, types of customers, distribution methods and regulatory environment. We are comprehensively managed as 1 business segment by our Chief Executive Officer.

Significant Concentrations

Our customers are primarily pharmaceutical and biotechnology companies that are located in the U.S. and Europe and with whom we have multi-year arrangements. Our accounts receivable balance contains billed and unbilled trade receivables from product sales, milestones (to the extent that they have been achieved and are due from the counterparty), and other contingent payments, as well as reimbursable costs from collaborative research and development agreements. As of March 31,June 30, 2021, our accounts receivable includes $26.2$25.0 million for unbilled net expense reimbursements from our collaboration partner Bristol-Myers Squibb Company (BMS) and $2.9$3.4 million under customer contracts from our collaboration partners. As of December 31, 2020, our accounts receivable included $38.7 million for unbilled net expense reimbursements from BMS and $0.2 million from customer contracts. We generally do not require collateral from our customers. We perform a regular review of our customers’ credit risk and payment histories, including payments made after period end. Historically, we have not experienced credit losses from our accounts receivable and recorded no bad debt expense for the three and six months ended March 31,June 30, 2021 and 2020. We have 0t recorded a reserve for credit losses at March 31,June 30, 2021 or December 31, 2020.

We are dependent on our suppliers and contract manufacturers to provide raw materials and drugs of appropriate quality and reliability and to meet applicable contract and regulatory requirements. In certain cases, we rely on single sources of supply of one or more critical materials. Consequently, in the event that supplies are delayed or interrupted for any reason, including as a result of the COVID-19 pandemic, our ability to develop and produce our drug candidates, our ability to supply comparator drugs for our clinical trials, or our ability to meet our supply obligations could be significantly impaired, which could have a material adverse effect on our business, financial condition and results of operations.

For our available-for-sale securities, we have significant concentrations of issuers in the banking and financial services industry. While our investment policy requires that we only invest in highly-rated securities and limit our exposure to any single issuer, a deterioration in this industry could have a material effect on our results of operations and financial position. Additionally, pursuant to our investment policy, we may sell securities before maturity if the issuer’s credit rating has been downgraded below our minimum credit rating requirements, which may result in a loss on the sale. Accordingly, if factors, including the effects of the COVID-19 pandemic, result in downgrades below our minimum credit rating requirements and if we decide to sell these securities, we may experience losses on such sales.

Collaborative Arrangements

We enter into collaboration arrangements with pharmaceutical and biotechnology collaboration partners, under which we may grant licenses to our collaboration partners to further develop and commercialize one of our proprietary drug candidates, either alone or in combination with the collaboration partners’ compounds, or grant licenses to partners to use our technology to research and develop their own proprietary drug candidates. We may also perform research, development, manufacturing and supply activities under our collaboration agreements. Consideration under these contracts may include an upfront payment,

purchase our proprietary PEGylation materials, drug candidates or additional contract research and development services under separate contracts.

Revenue Recognition

For elements of those arrangements that we determine should be accounted for under ASC 606, we assess which activities in our collaboration agreements are performance obligations that should be accounted for separately and determine the transaction price of the arrangement, which includes the assessment of the probability of achievement of future milestones and other potential consideration. For arrangements that include multiple performance obligations, such as granting a license or performing contract research and development activities or participation on joint steering or other committees, we allocate upfront and milestone payments under a relative standalone selling price method. Accordingly, we develop assumptions that require judgment to determine the standalone selling price for each performance obligation identified in the contract. These key assumptions may include revenue forecasts, clinical development timelines and costs, discount rates and probabilities of clinical and regulatory success.

Product Sales

Product sales are primarily derived from manufacturing and supply agreements with our customers. We have assessed our current manufacturing and supply arrangements and have generally determined that they provide the customer an option to purchase our proprietary PEGylation materials. Accordingly, we treat each purchase order as a discrete exercise of the customer’s option (i.e. a separate contract) rather than as a component of the overall arrangement. The pricing for the manufacturing and supply is generally at a fixed price and may be subject to annual producer price index (PPI) adjustments. We invoice and recognize product sales when title and risk of loss pass to the customer, which generally occurs upon shipment. Customer payments are generally due 30 days from receipt of invoice. We test our products for adherence to technical specifications before shipment; accordingly, we have not experienced any significant returns from our customers.

Royalty Revenue

License, Collaboration and other Revenue

Research and Development Expense

Research and development costs are expensed as incurred and include salaries, benefits and other operating costs such as outside services, supplies and allocated overhead costs. We perform research and development for our proprietary drug candidates and technology development and for certain third parties under collaboration agreements. For our proprietary drug candidates and our internal technology development programs, we invest our own funds without reimbursement from a third party. Where we perform research and development activities under a joint development collaboration, such as our collaboration with BMS, we record the cost reimbursement from our partner as a reduction to research and development expense when reimbursement amounts are due to us under the agreement.

Impairment of Assets and Other Costs for Terminated Program

On January 14, 2020, the joint FDA Anesthetic Drug Products Advisory Committee and Drug Safety and Risk Management Committee did not recommend approval of our NDANew Drug Application (NDA) for NKTR-181. As a result, we withdrew our NDA and decided to make no further investments in this program. As a result, in the three months ended March 31, 2020, we wrote off $19.7 million of advance payments to contract manufacturers for commercial batches of NKTR-181. We also incurred $25.5 million of additional costs, primarily for non-cancellable commitments to our contract manufacturers and certain severance costs. We present these costs in the Impairment of assets and other costs for terminated program line in our Condensed Consolidated Statement of Operations.

Income Taxes

For the three and six months ended March 31,June 30, 2021 and 2020, our income tax expense primarily results from taxable income in our Nektar India subsidiary. We have fully reserved our U.S. federal deferred tax assets generated from our net operating losses, as we believe it is not more likely than not that the benefit will be realized.

Shelf Registration

We currently have an effective shelf registration statement on Form S-3 (the 2021 Shelf Registration Statement) on file with the Securities and Exchange Commission,SEC, which expires in March 2024. The 2021 Shelf Registration Statement currently permits the offering, issuance and sale by us of up to an aggregate offering price of $300.0 million of common stock, preferred stock, debt securities and warrants in one or more offerings and in any combination, all of which may be offered, issued and sold in “at-the-market” sales pursuant to an equity distribution agreement with Cowen and Company, LLC (the Equity Distribution Agreement). No securities have been sold under the 2021 Shelf Registration Statement or the Equity Distribution Agreement.

Note 2 — Cash and Investments in Marketable Securities

At December 31, 2020, our gross unrealized gains and losses totaled $1.1 million and $0.2 million, respectively.

Note 3 — Inventory

We manufacture finished goods inventory upon receipt of firm purchase orders, and we may manufacture certain intermediate work-in-process materials and purchase raw materials based on purchase forecasts from our collaboration partners. We include direct materials, direct labor, and manufacturing overhead in inventory and determine cost on a first-in, first-out basis for raw materials and on a specific identification basis for work-in-process and finished goods. We value inventory at the lower of cost or net realizable value, and we write down defective or excess inventory to net realizable value based on historical experience or projected usage. We expense inventory related to our research and development activities as manufactured by us or when purchased. Before the regulatory approval of our drug candidates, we recognize research and development expense for the manufacture of drug products that could potentially be available to support the commercial launch of our drug candidates, if approved.

Note 4 — Co-Development Agreement with SFJ Pharmaceuticals and Development Derivative Liability

Other than the opportunity to receive Success Payments as outlined below, SFJ has no right to reimbursement of costs incurred by SFJ for the SCCHN Clinical Trial in the event that the Melanoma Clinical Trial and the SCCHN Clinical Trial do not achieve FDA approval. We will pay SFJ a series of success-based annual payments (collectively, the Success Payments) in the event of FDA approval of bempegaldesleukin for the Melanoma Indication, the SCCHN Indication, or both, and in the event of FDA approval of one additional bempegaldesleukin indication. The Success Payments do not begin until the substantial completion of the SCCHN Clinical Trial. The total success-based annual payments for the first indication approved by FDA, whether for the Melanoma Indication or the SCCHN Indication, is an aggregate of $450.0 million, paid in annual contractual payments over five years, with the first payment being $30.0 million, with the earliest possible payment expected to occur in late 2024 or early 2025, subject to the substantial completion of the SCCHN Clinical Trial. The total success-based payments for the second indication approved by FDA, whether for the Melanoma Indication or the SCCHN Indication, is an aggregate of $150.0 million, paid in annual contractual payments over seven years. Finally, in the event of FDA approval for bempegaldesleukin for any indication other than the Melanoma Indication or the SCCHN Indication, we will make a one-time payment of $37.5 million to SFJ. If the success criterion for the interim futility analysis is not met and SFJ winds down the SCCHN Clinical Trial, then the Success Payments, if any, for the Melanoma Indication and/or the additional bempegaldesleukin indication are reduced pro rata based on the costs incurred by SFJ for the SCCHN Clinical Trial over the aggregate commitment of $150.0 million.

The SFJ Agreement provides for certain positive and negative covenants, including restrictions on our ability to incur liens on our intellectual property related to bempegaldesleukin (the bempegaldesleukin IP), or assign or convey any right to receive income with respect to the bempegaldesleukin IP (other than royalty and other license fee obligations to licensors), except for the issuance of senior secured debt secured by all or substantially all of our assets, including the bempegaldesleukin IP.

The SFJ Agreement expires upon the payment of all Success Payments to SFJ, unless earlier terminated as provided under the SFJ Agreement. The SFJ Agreement may be terminated by either party for a safety or health concern for the patients, whether by the independent data monitoring company or by mutual agreement of both parties. The SFJ Agreement may also be terminated by either party for material breach or insolvency of the counterparty.

We valued the derivative using a scenario-based discounted cash flow method, whereby each scenario makes assumptions about the probability and timing of cash flows, and we discount such cash flows to present value using a risk-adjusted rate. The key inputs to the valuation include our estimates of the following: (i) the probability and timing of achieving FDA approval in the Melanoma Indication, the SCCHN Indication and any other bempegaldesleukin indication, (ii) the timing of the substantial completion of the SCCHN Clinical Trial that SFJ must achieve before receiving a Success Payment, (iii) the probability of termination of the study due to meeting the interim futility criteria, (iv) the amount of costs incurred by SFJ if the success criterion for the interim futility analysis is not met, (v) SFJ’s cost of borrowing (1.0%), and (vi) the Company’s imputed cost of borrowing for debt with similar terms (12.2%).

Note 5 — Liability Related to Sale of Future Royalties

The 2020 Purchase and Sale Agreement will automatically expire, and the payment of the 2020 Transaction Royalties to HCR will cease, when HCR has received payments of the 2020 Transaction Royalties equal to $210.0 million (the 2025 Threshold), if the 2025 Threshold is achieved on or prior to December 31, 2025, or $240.0 million, if the 2025 Threshold is not achieved on or prior to December 31, 2025 (or, if earlier, the date on which the last royalty payment under the relevant license agreements is made). If HCR has received payments of the 2020 Transaction Royalties equal to at least $208.0 million on or prior to December 31, 2025, we have the option to pay the difference between the 2025 Threshold and such 2020 Transaction Royalties, and the 2025 Threshold will be met and the 2020 Purchase and Sale Agreement will expire. After the 2020 Purchase and Sale Agreement expires, all rights to receive the 2020 Transaction Royalties return to Nektar.

On December 30, 2020, we received aggregate cash proceeds of $150.0 million for the sale of the 2020 Transaction Royalties. As part of the sale, we incurred approximately $3.8 million in transaction costs, which are amortized to interest expense over the estimated life of the 2020 Purchase and Sale Agreement. Although we sold all of our rights to receive royalties from these products, as a result of the limits on the 2020 Transaction Royalties to be received by HCR and our ongoing manufacturing and supply obligations related to the generation of these royalties, we will continue to account for these non-cash royalties as revenue, commencing with royalties for the three months ended December 31, 2020, which HCR received in the three months ended March 31, 2021. We recorded the $150.0 million in proceeds from this transaction as a liability (the 2020 Royalty Obligation) that will be amortized using the effective interest method over the estimated life of the 2020 Purchase and Sale Agreement.

As royalties are remitted to RPI and HCR by our licensees, the balances of the respective Royalty Obligations will be effectively repaid over the lives of the agreements. To determine the amortization of the Royalty Obligations, we are required to estimate the total amount of future royalty payments to be received by RPI and HCR, respectively. The sum of these amounts less the net proceeds we received will be recorded as non-cash interest expense over the lives of the respective Royalty Obligations. We periodically assess the estimated royalty payments to RPI and HCR from our licensees and to the extent the amount or timing of such payments is materially different than our original estimates, we will prospectively adjust the imputed interest rate and the related amortization of the applicable Royalty Obligation.

In addition, the 2012 and 2020 Purchase and Sale Agreements grant RPI and HCR, respectively, the right to receive certain reports and other information relating to the 2012 and 2020 Transaction Royalties, respectively, and contain other representations and warranties, covenants and indemnification obligations that are customary for transactions of this nature. To our knowledge, we are currently in compliance with these provisions of the 2012 and 2020 Purchase and Sale Agreements; however, if we were to breach our obligations, we could be required to pay damages to RPI and HCR, respectively, that are not limited to the purchase prices we received in the sale transactions. However, the time limitation we have to indemnify RPI with respect to any breach of these intellectual property-based representations and warranties has passed.

Note 6 — Commitments and Contingencies

From time to time, we are involved in lawsuits, arbitrations, claims, investigations and proceedings, consisting of intellectual property, commercial, employment and other matters, which arise in the ordinary course of business. We make provisions for liabilities when it is both probable that a liability has been incurred and the amount of the loss can be reasonably estimated. Such provisions are reviewed at least quarterly and adjusted to reflect the impact of settlement negotiations, judicial and administrative rulings, advice of legal counsel, and other information and events pertaining to a particular case. Litigation is inherently unpredictable. If any unfavorable ruling were to occur in any specific period, there exists the possibility of a material adverse impact on the results of our operations of that period and on our cash flows and liquidity.

In October 2018, we and certain of our executives were named in a putative securities class action complaint filed in the U.S. District Court for the Northern District of California (Case No. 18-cv—66-7-HSG, which we refer to as the Mulquin action). The Mulquin plaintiffs have challenged public statements Nektar made, about clinical trials of bempegaldesleukin between January 2017 and June 2018.2018, about the clinical trials of bempegaldesleukin. The Mulquin complaint was amended in May 2019. The defendants moved to dismiss and the court granted the motion without prejudice in July 2020. The Mulquin plaintiffs again amended their complaint and the defendants again moved to dismiss. In December 2020, the court dismissed the action with prejudice. The plaintiffs filed a notice of appeal in January 2021 and appellate briefing in the U.S. Court of Appeals for the Ninth Circuit is expected to be completed by September 2021.

A second putative securities class action was filed against the Company and certain of our executives in the U.S. District Court for the Northern District of California in August 2019 (Case No. 4-19-cv-05173, which we refer to as the Damiba action). The Damiba plaintiffs challenged public statements Nektar made, between February 2019 and May 2019, about its bempegaldesleukin clinical trials and collaboration with Bristol-Myers Squibb. After the Damiba plaintiffs filed an amended complaint and the defendants moved to dismiss, the court dismissed the action without prejudice in January 2021. The Damiba plaintiffs subsequently voluntarily dismissed the action, with prejudice, in March 2021.

In addition to the two securities actions (Mulquin(the Mulquin action and Damiba)the Damiba action), three sets of derivative actions have been filed against certain of the Company’s current and former officers and directors, purportedly on the Company’s behalf. These derivative actions are based on the allegations in the securities actions and on the premise that the Company’s officerofficers and directors breached their fiduciary duties by exposing the Company to one or both of the securities actions. The first derivative action was filed in the U.S. District Court for the District of Delaware in February 2019 (Case No. 1:19-cv-00322-MN-JLH). After amending their complaint several times, the plaintiffs in that action voluntarily dismissed their claims without prejudice in April 2021.

A second set of derivative actions was filed in February 2020 in the U.S. District Court for the Northern District of California (Case No. 4:20-cv-01088-JSW). The derivative actions in California have been consolidated and the Company has moved to dismiss on the basis that the plaintiffs have neither made a demand on the Company’s board of directors nor shown that a demand would be futile. The Company’s motion to dismiss has been under submission since December 2020.

An additionalA third derivative complaint was filed in February 2021 in the Court of Chancery of the State of Delaware (C.A. No. 2021-0118-PAF). No responseThe parties agreed to stay further proceedings in this action until thirty days after the complaint is due until May 2021.U.S. Court of Appeals for the Ninth Circuit's final resolution of the appeal in the Mulquin action.

Given the nature and status of these securities class action lawsuits and derivative complaints, we cannot reasonably estimate a potential future loss or a range of potential future losses. However, an unfavorable resolution could potentially have a material adverse effect on our business, financial condition, and results of operations or prospects, and potentially result in paying monetary damages. We have recorded 0 liability for these matters in our Condensed Consolidated Balance Sheets at either March 31,June 30, 2021 or December 31, 2020.

Indemnifications in Connection with Commercial Agreements

As part of our collaboration agreements with our partners related to the license, development, manufacture and supply of drugs and PEGylation materials based on our proprietary technologies and drug candidates, we generally agree to defend,

From time to time, we enter into other strategic agreements such as divestitures and financing transactions pursuant to which we are required to make representations and warranties and undertake to perform or comply with certain covenants, including our obligation to RPI described in Note 5. In the event it is determined that we breached certain of the representations and warranties or covenants made by us in any such agreements, we could incur substantial indemnification liabilities depending on the timing, nature, and amount of any such claims.

To date, we have not incurred costs to defend lawsuits or settle claims related to these indemnification obligations, representations or warranties. Because the aggregate amount of any potential indemnification obligation is not a stated amount, we cannot reasonably estimate the overall maximum amount of any such obligations. We have recorded 0 liabilities for these obligations in our Condensed Consolidated Balance Sheets at either March 31,June 30, 2021 or December 31, 2020.

Note 7 — Fair Value Measurement

Note 8 — License and Collaboration Agreements

We have entered into various collaboration agreements including license agreements and collaborative research, development and commercialization agreements with various pharmaceutical and biotechnology companies. Under these collaboration arrangements, we are entitled to receive license fees, upfront payments, milestone and other contingent payments, royalties, sales milestone payments, and payments for the manufacture and supply of our proprietary PEGylation materials and/or reimbursement for research and development activities. We generally include our costs of performing these services in research and development expense, except for costs for product sales to our collaboration partners which we include in cost of goods sold. We analyze our agreements to determine whether we should account for the agreements within the scope of ASC 808, and, if so, we analyze whether we should account for any elements under ASC 606.

During the three and six months ended March 31,June 30, 2021, and 2020, we recognized $18.8$20.5 million and $44.6$39.3 million, respectively, of revenue for performance obligations that we had satisfied in prior periods. This amount includesDuring the three and six months ended June 30, 2020, we recognized $42.1 million and $86.7 million, respectively, of revenue for performance obligations that we had satisfied in prior periods. These amounts include all of our royalty revenue and non-cash royalty revenue, as well as the $25.0 million milestone receivedand $50.0 million in milestones, respectively, recognized under our BMS Collaboration Agreement during the three and six months ended March 31,June 30, 2020, as further described below, because we had previously completed our performance obligations of granting the licenses.

As of March 31,June 30, 2021, our collaboration agreements with partners included potential future payments for development and regulatory milestones totaling approximately $1.7 billion, including amounts from our agreements with BMS and Eli Lilly and Company described below. In addition, under our collaboration agreements we are entitled to receive contingent sales milestone payments, other contingent payments and royalty payments, as described below.

There have been no material changes to our collaboration agreements in the three and six months ended March 31,June 30, 2021.

In April 2018, BMS paid us a non-refundable upfront cash payment of $1.0 billion. We are eligible to receive additional cash payments up to a total of approximately $1.455 billion (including the milestones which we have received under Amendment No. 1 described below) upon the achievement of certain development and regulatory milestones, and up to a total of

We determined that the BMS Collaboration Agreement falls within the scope of ASC 808, and we analogized to ASC 606 for the accounting for our performance obligation of the delivery of the licenses to develop and commercialize bempegaldesleukin.

During 2018, we aggregated the total consideration of $1.85 billion received under the agreements and allocated it between the stock purchase and the revenue-generating elements, because we and BMS negotiated the agreements together and the effective date of the BMS Collaboration Agreement was dependent upon the effective date of the Share Purchase Agreement. We recorded the estimated fair value of the shares of $790.2 million in stockholders’ equity. We allocated the remaining $1,059.8 million to the transaction price of the collaboration agreement, which we recognized in 2018. We consider the future potential development, regulatory and sales milestones to be variable consideration.

On January 9, 2020, we and BMS entered into Amendment No. 1 (the Amendment) to the BMS Collaboration Agreement. Pursuant to the Amendment, we and BMS agreed to update the Collaboration Development Plan under which we are collaborating and developing bempegaldesleukin. The cost sharing under the AmendmentBMS Collaboration Agreement remains unchanged. We received a non-refundable, creditable milestone payment of $25.0 million for the achievement of the first patient, first visit in the registrational muscle-invasive bladder cancer trial on January 30, 2020, which we recognized in the three months ended March 31, 2020. We have also received a non-refundable, non-creditable milestone payment of $25.0 million for the achievement of the first patient, first visit in the registrational adjuvant melanoma trial on July 27, 2020.2020, which we recognized in the three months ended June 30, 2020, because we concluded that, as of June 30, 2020, a significant reversal of this revenue was not probable. For the creditable milestone, BMS is entitled to deduct the amount paid from future development milestones due to us under the original agreement.

Other than these two milestones which we recognized during 2020, we continue to exclude the other milestones of up to $1.8 billion from the transaction price as of March 31,June 30, 2021 due to the significant uncertainties involved with clinical development and regulatory approval. We re-evaluate the transaction price at each reporting period and as uncertain events are resolved or other changes in circumstances occur.

As mentioned above, BMS shares certain percentages of development costs incurred by us and we share certain percentages of development costs incurred by BMS. We consider these activities to represent collaborative activities under ASC 808, and we recognize such cost sharing proportionately with the performance of the underlying services. We recognize BMS’ reimbursement of our costs as a reduction of research and development expense and our reimbursement of BMS’ costs as research and development expense. During the three and six months ended March 31,June 30, 2021, we recorded $24.8 million and $51.4 million, respectively, as a reduction of research and development expense for BMS’ share of our expenses, net of our share of BMS’ expenses. During the three and six months ended June 30, 2020, we recorded $26.7$33.9 million and $30.7$65.1 million, respectively, as a reduction of research and development expense for BMS’ share of our expenses, net of our share of BMS’ expenses. As of March 31,June 30, 2021, we have recorded an unbilled receivable of $26.2$25.0 million from BMS in accounts receivable in our Condensed Consolidated Balance Sheet.

On July 23, 2017, we entered into a worldwide license agreement (the Lilly Agreement) with Eli Lilly and Company (Lilly), which became effective on August 23, 2017, to co-develop NKTR-358, a novel immunological drug candidate that we invented. Under the terms of the agreement,Lilly Agreement, we (i) received an initial payment of $150.0 million in September 2017 and are eligible for up to $250.0 million in additional development and regulatory milestones, (ii) will co-develop NKTR-358 with Lilly, for which we were responsible for completing Phase 1 clinical development and certain drug product development and supply activities, (iii) share with Lilly Phase 1B and 2 development costs with 75% of those costs borne by Lilly and 25% of the costs borne by us, (iv) will have the option to contribute funding to Phase 3 development on an indication-by-indication basis ranging from 0 to 25% of development costs, and (v) will have the opportunity to receive a royalty rate up to the low twenties based upon our Phase 3 development cost contribution and the level of annual global product sales. Lilly will be responsible for all costs of global commercialization, and we will have an option to co-promote in the U.S. under certain conditions. A portion of the development milestones may be reduced by 50% under certain conditions, related to the final formulation of the approved product and the timing of prior approval (if any) of competitive products with a similar mechanism of action, which could reduce these milestone payments by 75% if both conditions occur.

The agreementLilly Agreement will continue until Lilly no longer has any royalty payment obligations or, if earlier, the termination of the agreement in accordance with its terms. The agreementLilly Agreement may be terminated by Lilly for convenience, and may also be terminated under certain other circumstances, including material breach.

We identified our license grant to Lilly, our Phase 1 clinical development obligation and our drug product development obligation as the significant performance obligations in the arrangement. Based on our estimates of the standalone selling prices of the performance obligations, we allocated the $150.0 million upfront payment as $125.9 million to the license, $17.6 million to our portion of the Phase 1 clinical development and $6.5 million to the drug product development. We recognized the revenue

Although we are entitled to significant development milestones under this arrangement, through March 31,June 30, 2021, we have excluded such milestones from the transaction price due to the significant uncertainties involved with clinical development. We re-evaluate the transaction price at each reporting period and as uncertain events are resolved or other changes in circumstances occur.

Other

Additionally, we have collaborationscollaboration agreements for products under development, under which we are entitled to up to a total of $40.0 million of development milestones, as well as sales milestones upon achievement of annual sales targets and royalties based on net sales of commercialized products, if any. However, given the current phase of development of the potential products under these collaboration agreements, we cannot estimate the probability or timing of achieving these milestones, and, therefore, have excluded all development milestones from the respective transaction prices for these agreements.

Note 9 — Stock-Based Compensation

The stock-based compensation expense reported in impairment of assets and other costs for terminated program resulted from executive severance. We accounted for this as a liability award as of March 31, 2020, which we reclassified into equity in three months ended June 30, 2020.

Note 10 — Net Loss Per Share

We calculate basic net loss per share based on the weighted-average number of common shares outstanding during the periods presented and calculate diluted net loss per share based on the weighted-average number of shares of common stock

The following discussion contains forward-looking statements that involve risks and uncertainties. See the section entitled "Forward-Looking Statements" that appears at the beginning of this report. Our actual results could differ materially from those discussed here. Factors that could cause or contribute to such differences include, but are not limited to those discussed in this section as well as factors described in Part II, Item 1A “Risk Factors.”

Overview

Nektar Therapeutics is a research-based biopharmaceutical company that discovers and develops innovative new medicines in areas of high unmet medical need. Our research and development pipeline of new investigational drugs includes potential therapies for oncology, immunology and virology. We leverage our proprietary and proven chemistry platform to discover and design new drug candidates. These drug candidates utilize our advanced polymer conjugate technology platforms, which are designed to enable the development of new molecular entities that target known mechanisms of action. We continue to make significant investments in building and advancing our pipeline of proprietary drug candidates as we believe that this is the best strategy to build long-term stockholder value.

The BMS Collaboration Agreement entitles Nektar to receive up to $1.455 billion of clinical, regulatory and commercial launch milestones. Of these milestones, we received a non-refundable, creditable milestone payment of $25.0 million for the first patient, first visit in the registrational muscle-invasive bladder cancer trial, which was achieved on January 30, 2020, and also received a non-refundable, non-creditable milestone payment of $25.0 million for the first patient, first visit in the registrational adjuvant melanoma trial, which we achieved on July 27, 2020. Of the remaining milestones, $625.0 million are associated with the approval and launch of bempegaldesleukin in its first indication in the U.S., EUEuropean Union (EU) and Japan (which reflects the reduction for the $25.0 million nonrefundable,non-refundable, creditable milestone for the first patient, first visit in the muscle-invasive bladder cancer trial). As a result, whether and when bempegaldesleukin is approved in any indication will have a significant impact on our future results of operations and financial condition.

We are also combiningconducting studies of bempegaldesleukin in combination with NKTR-262. NKTR-262 is a small molecule agonist that targets toll-like receptors (TLRs) found on innate immune cells in the body. NKTR-262 is designed to stimulate the innate immune system and promote maturation and activation of antigen-presenting cells, (APCs), such as dendritic cells, which are critical to induce the body’s adaptive immunity and create antigen-specific cytotoxic T cells. NKTR-262 is being developed as an intra-tumoral injection in combination with systemic bempegaldesleukin to induce an abscopal response and achieve the goal of tumor regression in cancer patients treated with both therapies. The Phase 1/2 dose-escalation and expansion trial in patients with solid tumors is currently ongoing.

Our next most advanced I-O program is NKTR-255. NKTR-255 is a biologic that targets the IL-15 pathway in order to activate the body’s innate and adaptive immunity. Activation of the IL-15 pathway enhances the survival and function of NKnatural killer (NK) cells and induces survival of both effector and CD8CD8+ memory T cells. Recombinant human IL-15 is rapidly cleared from the body and must be administered frequently and in high doses limiting its utility due to toxicity. Through optimal engagement of the IL-15 receptor complex, NKTR-255 is designed to enhance functional NK cell populations and formation of long-term immunological memory, which may lead to sustained and durable anti-tumor immune response. Preclinical findings suggest NKTR-255 has the potential to synergistically combine with antibody-dependent cellular toxicity molecules as well as to enhance CAR-T therapies. We have initiated a Phase 1 dose escalation and expansion clinical study of NKTR-255 in adults with relapsed or refractory non-Hodgkin lymphoma or multiple myeloma, as well as a Phase 1/2 clinical study of NKTR-255 in patients with relapsed or refractory head and neck squamous cell carcinoma or colorectal cancer. At the 2020 Society for Immunotherapy of Cancer (SITC) Annual Meeting, we reported early findings from the Phase 1 dose escalation study that demonstrated expansion of NK and CD8+ T cells in patients with multiple myeloma and non-Hodgkin lymphoma.

In immunology, we are developing NKTR-358, which is designed to correct the underlying immune system imbalance in the body that occurs in patients with autoimmune disease. NKTR-358 is designed to optimally target the IL-2 receptor complex in order to stimulate proliferation and growth of regulatory T cells. NKTR-358 is being developed as a once or twice monthly self-administered injection for a number of autoimmune diseases. In 2017, we entered into a worldwide license agreement with Eli Lilly and Company (Lilly) to co-develop NKTR-358. We received an initial payment of $150.0 million in September 2017 and are eligible for up to an additional $250.0 million for development and regulatory milestones. We were responsible for completing Phase 1 clinical development and certain drug product development and supply activities. We also share Phase 2 development costs with Lilly, with Lilly responsible for 75% and Nektar responsible for 25% of these costs. We will have the option to contribute funding to Phase 3 development on an indication-by-indication basis, ranging from zero to 25% of the Phase 3 development costs and receive a royalty rate on global NKTR-358 sales up to the low twenties based upon our Phase 3 development cost contribution and the level of annual global product sales. Lilly will be responsible for all costs of global commercialization and we will have an option to co-promote in the U.S. under certain conditions.

We have completed a Phase 1 dose-finding trial of NKTR-358 to evaluate single-ascending doses of NKTR-358 in approximately 100 healthy patients. Results from this study demonstrated a multiple-fold increase in regulatory T cells with no change in CD8 positiveCD8+ or natural killerNK cell levels and no dose-limiting toxicities were observed. We also completed treatment of a Phase 1 multiple-ascending dose trial to evaluate NKTR-358 in patients with systemic lupus erythematosus (SLE). Lilly is conducting two Phase 1b studies in patients with psoriasis and atopic dermatitis, hasand initiated a Phase 2 study in SLE in October 2020 and has initiated a Phase 2 study in ulcerative colitis.colitis in March 2021. In addition, Lilly is planning to initiate two new Phase 2 studies in undisclosed auto-immune indications.two different immune-mediated diseases.

In virology, we received on October 22, 2020, FDA clearance for an Investigational New Drug application for bempegaldesleukin to be evaluated in a Phase 1b clinical study in adult patients who have been diagnosed with mild COVID-19 infection. The study design allows us to evaluate whether bempegaldesleukin’s adaptive immune-stimulating mechanism to promote priming and proliferation of T cells and NK cells could be useful in the emerging treatment options for COVID-19. Enrollment in the Phase 1b randomized, double-blind, placebo-controlled trial began in November 2020. We have also entered into a preclinical research collaboration with Gilead to test the combination of NKTR-255 with therapies in Gilead’s antiviral portfolio.

The level of our future research and development investment will depend on a number of trends and uncertainties including clinical study outcomes, future studies required to advance programs to regulatory approval, and the economics related to potential future collaborations that may include up-front payments, development funding, milestones, and royalties. Over the next several years, we plan to continue to make significant investments to advance our early drug candidate pipeline.

We have historically derived all of our revenue and substantial amounts of operating capital from our collaboration agreements including the BMS Collaboration Agreement, pursuant to which we have recognized $1.11 billion in revenue and recorded $790.2 million in additional paid in capital for shares of our common stock issued in the transaction. While in the near-term we continue to expect to generate substantially all of our revenue from collaboration arrangements, including the potential remaining $1.405 billion in development and regulatory milestones under the BMS collaboration, in the medium- to long-term, our plan is to generate significant commercial revenue from proprietary products, the first of which being bempegaldesleukin, if approved. Since we do not have experience commercializing products or an established commercialization organization, there will be substantial risks and uncertainties in future years as we build commercial, organizational, and operational capabilities.

Our business is subject to significant risks, including the risks inherent in our development efforts, the results of our clinical trials, our dependence on the marketing efforts by our collaboration partners, uncertainties associated with obtaining and enforcing patents, the lengthy and expensive regulatory approval process and competition from other products. For a discussion of these and some of the other key risks and uncertainties affecting our business, see Item 1A. Risk1A “Risk Factors.”

While the approved drugs and clinical development programs described above are key elements of our future success, we believe it is critically important that we continue to make substantial investments in our earlier-stage drug candidate pipeline. We have several drug candidates in earlier stage clinical development or being explored in research that we are preparing to advance into the clinic in future years. We are also advancing several other drug candidates in preclinical development in the areas of I-O, immunology, and other therapeutic indications. We believe that our substantial investment in research and development has the potential to create significant value if one or more of our drug candidates demonstrates positive clinical results, receives regulatory approval in one or more major markets and achieves commercial success. Drug research and development is an inherently uncertain process with a high risk of failure at every stage prior to approval. The timing and outcome of clinical trial results are extremely difficult to predict. Clinical development successes and failures can have a disproportionately positive or negative impact on our scientific and medical prospects, financial condition and prospects, results of operations and market value.

In March 2020, COVID-19, the disease resulting from a novel strain of coronavirus infection, was declared a global pandemic. Many countries, including the United States and India, initially took steps such as restricting travel, closing schools, and issuing shelter-in-place orders to slow or moderate the spread of the virus. More recently, states and countries have adopted individualized approaches to respond to the COVID-19 pandemic. In particular, the emergence of new variants of the coronavirus, such as the Delta variant, and local resurgences in number and rates of infections, and the further spread of the virus may result in the return of prior restrictions or the institution of restrictions in the affected areas.areas, which could have an adverse effect on our business, including our clinical trial timelines. Although vaccines intended to reduce the incidence and severity of infection are available pursuant to an Emergency Use Authorization granted by the FDA in the U.S. (and under similar authorizations by other health authorities in our countries), it remains unclear how long the negative impacts caused by the coronavirus will continue into the future.

Currently, with respect to the operation of our facilities, we are closely adhering to applicable guidelines and orders. Operationsoperations in research, manufacturing and maintenance that occur within our facilities are continuing in accordance with the permissions granted under local government ordinances. Recently, in view of the surge of COVID-19 cases occurring in India, we have further decreased the number of employees working at our facilities in Hyderabad.applicable guidelines and orders. Across all our locations, we have instituted a temporary work from home policy for all office personnel who do not need to work on site to maintain productivity. At this time, weWe have not identified a material changerecently allowed these employees to our productivity as a result of these measures, but this could change, particularly if restricted travel, closed schools,voluntarily return to work on site with appropriate health and shelter-in-place orders are not removed or significantly eased in the areas in which we operate.safety measures.

The safety and well-being of our employees, and the patients and healthcare providers in our clinical trial programs, are of first and foremost importance to us. We believe that the safety measures we are taking and instructing our contractors to take in response to the COVID-19 pandemic meet or exceed the guidance and requirements issued from government and public health officials. We continue to monitor our operations and applicable government recommendations in light of new developments in the ongoing COVID-19 pandemic.

We and our partners are currently engaged in the clinical testing of our proprietary drug candidates and the COVID-19 pandemic introduces significant challenges to our clinical development programs which are central to our business. The evolving situation around the COVID-19 pandemic, along with the resulting public health guidance measures that have been put into place, have thus far had varying impacts on the clinical testing of our proprietary drug candidates depending on the therapeutic indication, geographic distribution of clinical trial sites, the clinical trial stage, and, in certain cases, our partners’ general corporate approach to the COVID-19 pandemic. The rapid development and fluidity of the COVID-19 pandemic precludes any firm estimates as to the ultimate effect this disease will have on our clinical trials, our operations and our business. As a result, any current assessment of the effects of the COVID-19 pandemic, including the impact of this disease on our specific clinical programs as discussed below, is difficult to predict and subject to change.

With regard to Nektar’s ongoing Phase 1/2 clinical study of NKTR-262 (the Phase 1/2 REVEAL study),in patients with solid tumors, this study has largely remained on trackschedule although we have experienced some challenges with new investigator site initiations. Nektar’s Phase 1 clinical study of NKTR-255 in patients with relapsed/refractory hematologic malignancies has enrolled slower than anticipated due to challenges caused by the COVID-19 pandemic, and the dose-escalation monotherapy portion of the study is expected to be completed in the firstsecond half of 2021. For both of these Nektar-run clinical programs, the ongoing COVID-19 pandemic could still impact investigator site initiations and trial enrollment despite our mitigation efforts.

For clinical studies of our proprietary drug candidates being run by our partners, BMS is enrolling patients in each of the BMS-led registration studies and re-started initiation of new investigator sites in the third quarter of 2020 following a pause in the initiation of new investigator sites it instituted for all of its studies as a result of the COVID-19 pandemic. In the summer of 2020, BMS extended theirits timeline estimates by approximately six months for the first data read-outs for the first-line melanoma trial. We will continue to monitor the progress of enrollment of the BMS-led studies and projections for topline clinical outcome data.