NOTES TO THE UNAUDITED CONDENSED CONSOLIDATED FINANCIAL STATEMENTS

Note 1—Business and Basis of Presentation:

Business:

Puma Biotechnology, Inc., or the Company, is a biopharmaceutical company based in Los Angeles, California with a focus on the development and commercialization of innovative products to enhance cancer care. The Company in-licenses the global development and commercialization rights to three drug candidates—PB272 (neratinib (oral)), PB272 (neratinib (intravenous)) and PB357. Neratinib is a potent irreversible tyrosine kinase inhibitor that blocks signal transduction through the epidermal growth factor recept ors HER1, HER2 and HER4. Currently, the Company is primarily focused on the U.S. commercialization of NERLYNX (neratinib), its first U.S. Food and Drug Administration, or FDA, approved product, and on the further development of the oral version of neratini b for additional indications in the treatment of HER2-positive breast cancer. The Company believes that neratinib has clinical application in the treatment of several other cancers as well, including non-small cell lung cancer and other tumor types that over-express or have a mutation in HER2.

In November 2012, the Company established and incorporated Puma Biotechnology Ltd., a wholly owned subsidiary, for the sole purpose of serving as the Company’s legal representative in the United Kingdom and the European Union in connection with the Company’s clinical trial activity in those countries.  In December 2018, the Company established and incorporated Puma Biotechnology, B.V., a wholly owned subsidiary, for the sole purpose transferring the above mentioned marketing authorisation in preparation of the departure of the United Kingdom from the European Union.  Puma Biotechnology, B.V., is currently the holder of the marketing authorisation for commercialization of NERLYNX in the European Union.

Basis of Presentation:

The Company is focused on developing and commercializing neratinib for the treatment of patients with human epidermal growth factor receptor type 2, or HER2-positive, breast cancer, HER2 mutated non-small cell lung cancer, HER2-negative breast cancer that has a HER2 mutation and other solid tumors that have an activating mutation in HER2.  The Company has reported a net loss of approximately $10.1 million and negative cash flows from operations of approximately $16.1 million for the three months ended March 31, 2019.  The Company believes that it will continue to incur net losses and negative net cash flows from operating activities through the drug development process and global commercialization.

The Company has incurred significant operating losses and negative cash flows from operations since its inception.  On July 17, 2017, the Company received FDA approval for its first product, NERLYNX® (neratinib), formerly known as PB272 (neratinib (oral)), for the extended adjuvant treatment of adult patients with early stage HER2-overexpressed/amplified breast cancer following adjuvant trastuzumab-based therapy.  Following FDA approval in July 2017, NERLYNX became available by prescription in the United States, and the Company commenced commercialization.

The Company in-licenses PB272 (neratinib (oral)), PB272 (neratinib (intravenous)) and PB357, as well as certain related compounds, from Pfizer Inc., or Pfizer. The Company is required to make substantial payments to Pfizer upon the achievement of certain milestones and has contractual obligations for clinical trial contracts.

Additionally, the Company has entered into exclusive license agreements with Specialised Therapeutics Asia Pte Ltd., or STA, Medison Pharma Ltd., or Medison, CANbridgepharma Limited, or CANbridge, Pint Pharma International SA, or Pint, and, most recently, Knight Therapeutics Inc., or Knight, and Pierre Fabre Medicament SAS, or Pierre Fabre, to pursue regulatory approval and/or commercialize NERLYNX, if approved, in various specified regions outside of the United States.  The Company plans to continue to pursue commercialization of NERLYNX in additional countries outside the United States, if approved, and is evaluating various commercialization options in those countries, including developing a direct salesforce, contracting with third parties to provide sales and marketing capabilities, or some combination of these two options.  In September 2018, the European Commission, or EC, granted marketing authorisation for NERLYNX for the extended adjuvant treatment of adult patients with early stage hormone receptor positive HER2-overexpressed/amplified breast cancer and who are less than one year from the completion of prior adjuvant trastuzumab based therapy.  

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The Company’s commercialization, R&D, or marketing efforts may require funding in addition to the cash and cash equivalents totaling approximately $48.8 million and marketable securities totaling approximately $ 101.6 million available at March 31, 2019.  The Company believes that its exi sting cash and cash equivalents and marketable securities as of March 31, 2019 and proceeds that will become available to the Company through product sales and upfront license payments are sufficient to satisfy its operating cash and needs for at least one year after the filing of the Quarterly Report on Form 10-Q in which these financial statements are included. The Company continues to remain dependent on its ability to obtain sufficient funding to sustain operations and continue to successfully commercia lize neratinib in the United States.  While the Company has been successful in raising capital in the past, there can be no assurance that it will be able to do so in the future.  The Company’s ability to obtain funding may be adversely impacted by uncerta in market conditions, unfavorable decisions of regulatory authorities or adverse clinical trial results.  The outcome of these matters cannot be predicted at this time.  

Since its inception through March 31, 2019, the Company’s financing has primarily been proceeds from product and license revenue, public offerings of its common stock, private equity placements, and borrowings under its loan and security agreement with Silicon Valley Bank, or SVB and Oxford Finance LLC, or Oxford.          

Note 2—Significant Accounting Policies:

The significant accounting policies followed in the preparation of these unaudited condensed consolidated financial statements are as follows:

Financial Instruments:

The carrying value of financial instruments, such as cash equivalents, accounts receivable and accounts payable, approximate their fair value because of their short-term nature. The carrying value of long-term debt approximates its fair value as the principal amounts outstanding are subject to variable interest rates that are based on market rates, which are regularly reset.

Use of Estimates:

The preparation of consolidated financial statements in conformity with Generally Accepted Accounting Principles, or GAAP, requires management to make estimates and assumptions that affect reported amounts of assets and liabilities, and disclosure of contingent assets and liabilities at the date of the balance sheet, and reported amounts of expenses for the period presented. Accordingly, actual results could differ from those estimates.

Significant estimates include estimates for variable consideration for which reserves were established.  These estimates are included in the calculation of net revenues and include trade discounts and allowances, product returns, provider chargebacks and discounts, government rebates, payor rebates, and other incentives, such as voluntary patient assistance, and other allowances that are offered within contracts between the Company and its customers, payors, and other indirect customers relating to the Company’s sale of its products.

Principles of Consolidation:

The unaudited condensed consolidated financial statements include the accounts of the Company and its wholly owned subsidiaries. All intercompany balances and transactions have been eliminated in consolidation.

Investment Securities:

The Company classifies all investment securities (short term and long term) as available-for-sale, as the sale of such securities may be required prior to maturity to implement management’s strategies. These securities are carried at fair value, with the unrealized gains and losses, reported as a component of accumulated other comprehensive loss in stockholders’ equity until realized. Realized gains and losses from the sale of available-for-sale securities, if any, are determined on a specific identification basis.  A decline in the market value of any available-for-sale security below cost that is determined to be other than temporary results in the revaluation of its carrying amount to fair value. The impairment is charged to earnings and a new cost basis for the security is established. Premiums and discounts are amortized or accreted over the life of the related security as an adjustment to yield using the straight-line method. Interest income is recognized when earned.

License Fees and Intangible Assets:

The Company expenses amounts paid to acquire licenses associated with products under development when the ultimate recoverability of the amounts paid is uncertain and the technology has no alternative future use when acquired. Acquisitions of

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technology licenses are charged to expens e or capitalized based upon the asset achieving technological feasibility in accordance with management’s assessment regarding the ultimate recoverability of the amounts paid and the potential for alternative future use. The Company has determined that tec hnological feasibility for its product candidates is reached when the requisite regulatory approvals are obtained to make the product available for sale.  The Company capitalizes technology licenses upon reaching technological feasibility.

The Company maintains definite-lived intangible assets related to the Company’s license with Pfizer. These assets are amortized over their remaining useful lives, which are estimated based on the shorter of the remaining patent life or the estimated useful life of the underlying product. Intangible assets are amortized using the economic consumption method if anticipated future revenues can be reasonably estimated. The straight-line method is used when future revenues cannot be reasonably estimated. Amortization costs are recorded as part of cost of sales.

The Company assesses its intangible assets for impairment if indicators are present or changes in circumstance suggest that impairment may exist. Events that could result in an impairment, or trigger an interim impairment assessment, include the receipt of additional clinical or nonclinical data regarding one of the Company’s drug candidates or a potentially competitive drug candidate, changes in the clinical development program for a drug candidate, or new information regarding potential sales of the drug. If impairment indicators are present or changes in circumstance suggest that impairment may exist, the Company performs a recoverability test by comparing the sum of the estimated undiscounted cash flows of each intangible asset to its carrying value on the consolidated balance sheet. If the undiscounted cash flows used in the recoverability test are less than the carrying value, the Company would determine the fair value of the intangible asset and recognize an impairment loss if the carrying value of the intangible asset exceeds its fair value. The FDA approval of NERLYNX in July 2017 triggered a one-time milestone payment pursuant to the Company’s license agreement with the Pfizer. The Company capitalized the milestone payment as an intangible asset and is amortizing the asset to cost of sales on a straight-line basis through 2030, the estimated useful life of the licensed patent. The Company recorded amortization expense related to its intangible asset of $1.0 million   for the three months ended March 31, 2019, respectively. As of March 31, 2019, estimated future amortization expense related to the Company’s intangible asset was approximately $2.9 million for the remainder of 2019, approximately $3.9 million for each year starting 2020 through 2029, and approximately $1.0 million for 2030.

Royalties:

Royalties incurred in connection with the Company’s license agreement with Pfizer, as disclosed in Note 13 Commitments and Contingencies, are expensed to cost of sales as revenue from product sales is recognized.

Leases:

In February 2016, the FASB issued an accounting standards update which requires lessees to recognize most leases on the balance sheet with a corresponding right-of-use asset. Right-of-use assets represent the Company’s right to use an underlying asset for the lease term and lease liabilities represent our obligation to make lease payments arising from the lease. Right-of-use assets and lease liabilities are recognized at the lease commencement date based on the estimated present value of fixed lease payments over the lease term. Leases will be classified as financing or operating which will drive the expense recognition pattern. For lessees, the income statement presentation and expense recognition pattern for financing and operating leases is similar to the current model for capital and operating leases, respectively. The Company has elected to exclude short-term leases. The update also requires additional disclosures that will better enable users of financial statements to assess the amount, timing, and uncertainty of cash flows arising from leases. The Company adopted this guidance as of January 1, 2019, the required effective date, using the effective date transition method. As permitted under the effective date transition method, financial information and disclosure for periods prior to the date of initial application will not be updated. An adjustment to opening retained earnings was not required in conjunction with our adoption. For additional information, see Note 6 — Leases. We have elected not to reassess whether expired or existing contracts contain leases, nor did we reassess the classification of existing leases as of the adoption date.

The Company leases office space and copy machines, all of which are operating leases. Most leases include the option to renew and the exercise of the renewals options is at the Company’s sole discretion. Options to extend or terminate a lease are considered in the lease term to the extent that the option is reasonably certain of exercise. The leases do not include the options to purchase the leased property. The depreciable life of assets and leasehold improvements are limited by the expected lease term.  Covenants imposed by the leases include letters of credit required to be obtained by the lessee.

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The incremental borrowing rate presents the rate of interest that the Company would expect to pay on a collateralized basis to borrow an amount equal to the lease payments under similar terms. When determinable, the Company uses the rate implicit in the le ase to determine the present value of lease payments. As the Company’s leases do not provide an implicit rate, the Company uses its incremental borrowing rate based on the information available at the commencement date in determining the present value of l ease payments. The Company’s average incremental borrowing rate, or IBR, for existing leases on the transition date (January 1, 2019) was calculated as 10.9%.  

Inventory:

The Company values its inventories at the lower of cost and estimated net realizable value. The Company determines the cost of its inventories, which includes amounts related to materials and manufacturing overhead, on a first-in, first-out basis. The Company performs an assessment of the recoverability of capitalized inventory during each reporting period, and it writes down any excess and obsolete inventories to their estimated realizable value in the period in which the impairment is first identified. Such impairment charges, should they occur, are recorded within the cost of sales. The determination of whether inventory costs will be realizable requires estimates by management. If actual market conditions are less favorable than projected by management, additional write-downs of inventory may be required, which would be recorded as a cost of sales in the consolidated statements of operations and comprehensive loss.

The Company capitalizes inventory costs associated with the Company’s products after regulatory approval, if any, when, based on management’s judgment, future commercialization is considered probable and the future economic benefit is expected to be realized. The Company previously expensed $4.5 million of product prior to receipt of marketing approval, which was recorded as research and development expense at the time it was incurred. Inventory that can be used in either the production of clinical or commercial product is recorded as research and development expense when selected for use in a clinical trial. Starter kits, provided to patients prior to insurance approval, are expensed by the Company to sales and marketing expense as incurred.

As of March 31, 2019, the Company’s inventory balance consisted primarily of raw materials purchased subsequent to FDA approval of NERLYNX.

Revenue Recognition:

The Company adopted ASC Topic 606 - Revenue from Contracts with Customers, or ASC 606, on January 1, 2017.  This standard applies to all contracts with customers, except for contracts that are within the scope of other standards, such as leases, insurance, collaboration arrangements, and financial instruments. Under ASC 606, when its customer obtains control of the promised goods or services, an entity recognizes revenue in an amount that reflects the consideration which the entity expects to be entitled in exchange for those goods or services. The Company had no contracts with customers until after the FDA approved NERLYNX in July 2017.  Subsequent to receiving FDA approval, the Company entered into a limited number of arrangements with specialty pharmacies and specialty distributors in the United States to distribute NERLYNX. These arrangements are the Company’s initial contracts with customers.  The Company has determined that these sales channels with customers are similar.

To determine revenue recognition for arrangements that an entity determines are within the scope of ASC 606, the entity performs the following five steps: (i) identifies the contract(s) with a customer, (ii) identifies the performance obligations in the contract, (iii) determines the transaction price, (iv) allocates the transaction price to the performance obligations in the contract, and (v) recognizes revenue when (or as) the entity satisfies a performance obligation. The Company only applies the five-step model to arrangements that meet the definition of a contract under ASC 606, including when it is probable that the entity will collect the consideration it is entitled to in exchange for the goods or services it transfers to the customer. At contract inception, once the contract is determined to be within the scope of ASC 606, the Company assesses the goods or services promised within each contract and determines those that are performance obligations, and assesses whether each promised good or service is distinct. The Company then recognizes as revenue the amount of the transaction price that is allocated to the respective performance obligation when (or as) the performance obligation is satisfied. For a complete discussion of accounting for product revenue, see Product Revenue, Net (below).

Product Revenue, Net:

The Company sells NERLYNX to a limited number of specialty pharmacies and specialty distributors in the United States. These customers subsequently resell the Company’s products to patients and certain medical centers or hospitals. In addition to distribution agreements with these customers, the Company enters into arrangements with health care providers and payors that provide for government mandated and/or privately negotiated rebates, chargebacks and discounts with respect to the purchase of the Company’s products.

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The Company recognizes revenue on product sales when the specialty pharmacy or specialty distributor, as applicable, obtains control of the Company's product, which occurs at a point in time (upon delivery). Product revenue is recorded net of applicable re serves for variable consideration, including discounts and allowances.  The Company’s payment terms range between 10 and 68 days.

Shipping and handling costs for product shipments occur prior to the customer obtaining control of the goods, and are recorded in cost of sales.

If taxes should be collected from these customers relating to product sales and remitted to governmental authorities, they will be excluded from revenue. The Company expenses incremental costs of obtaining a contract when incurred, if the expected amortization period of the asset that the Company would have recognized is one year or less. However, no such costs were incurred during the three months ended March 31, 2019.

Product revenue from customers who individually accounted for 10% or more of the Company’s total revenue for the three months ended March 31, 2019 consisted of the following, shown as a percentage of total revenue:

License Revenue:

The Company also recognizes license revenue under certain of the Company’s sub-license agreements that are within the scope of ASC Topic 606. The terms of these agreements may contain multiple performance obligations, which may include licenses and research and development activities. The Company evaluates these agreements under ASC Topic 606 to determine the distinct performance obligations. Non-refundable, upfront fees that are not contingent on any future performance and require no consequential continuing involvement by the Company, are recognized as revenue when the license term commences and the licensed data, technology or product is delivered. The Company defers recognition of non-refundable upfront license fees if the performance obligations are not satisfied.

Prior to recognizing revenue, the Company makes estimates of the transaction price, including variable consideration that is subject to a constraint. Amounts of variable consideration are included in the transaction price to the extent that it is probable that a significant reversal in the amount of cumulative revenue recognized will not occur and when the uncertainty associated with the variable consideration is subsequently resolved.

If there are multiple distinct performance obligations, the Company allocates the transaction price to each distinct performance obligation based on its relative standalone selling price. The standalone selling price is generally determined based on the prices charged to customers or using expected cost plus margin. Revenue is recognized by measuring the progress toward complete satisfaction of the performance obligations using an input measure.

Knight Agreement

During the first quarter of 2019, the Company entered into a sub-license agreement, or the Knight Agreement, with Knight. Pursuant to the Knight Agreement, the Company granted to Knight, under certain of the Company’s intellectual property rights relating to neratinib, an exclusive, sublicensable (under certain circumstances) license (i) to commercialize any product containing neratinib and certain related compounds in Canada, (ii) to seek and maintain regulatory approvals for the licensed products in Canada and (iii) to manufacture the licensed products anywhere in the world solely for the development and commercialization of the licensed products in Canada for human use, subject to the terms of the Knight Agreement and the related supply agreement.   During the first quarter of 2019, a non-refundable, upfront license fee was received and recognized as license revenue in accordance with ASC Topic 606.   The Company satisfied the necessary performance obligations to recognize this license revenue under the terms of the arrangement. This license agreement met the contract existence criteria and contained distinct, identifiable performance obligations for which the stand-alone selling prices were readily determinable and allocable.  As a separate promise under the terms of the license agreement, the Company is obligated to supply Knight with the licensed product in accordance with the supply agreement entered in connection with the license agreement.  The Company is also obligated to participate in a Joint Steering Committee, which was identified as a separate performance obligation.  To determine the stand-alone selling price, the Company estimated the transaction prices, including any variable consideration, at contract inception and determined the fair value of such obligations based on similar

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arrangements. When determining the transaction prices, the Company assumed that the goods or services will be transferred to the customer based on the terms of the existing contract, and did not take into consideration the possibility of a contract being canceled, renewed, or modified. The Company noted there was no additional variable consideration, significant financing components, non-cash consideration, or consideration payable to the customer in this agreement. This li cense agreement also includes potential future milestone and royalty payments due to the Company upon successful completion of certain separate, distinct performance obligations.   Pursuant to the Knight Agreement, the Company will potentially receive upfro nt, regulatory and commercial milestone payments totaling up to $7.2 million.  In addition, the Company is entitled to receive significant double-digit royalties calculated as a percentage of net sales of the licensed products in Canada.   At this time, the Company cannot estimate when these milestone-related performance obligations are expected to be achieved.

Pierre Fabre Agreement

Additionally, during the first quarter of 2019, the Company entered into a sub-license agreement, or the Pierre Fabre Agreement, with Pierre Fabre Medicament SAS, or Pierre Fabre.  The Pierre Fabre Agreement granted intellectual property rights and set forth the parties’ respective obligations with respect to development, commercialization and supply of the licensed product in   European countries excluding Russia and Ukraine, along with countries in North Africa and francophone countries of West Africa. During the first quarter of 2019, a non-refundable, upfront license fee of $51.0 million was recognized as license revenue in accordance with ASC Topic 606. The Company satisfied the necessary performance obligations to recognize this license revenue under the terms of the arrangement. The Pierre Fabre Agreement met the contract existence criteria and contained distinct, identifiable performance obligations for which the stand-alone selling prices were readily determinable and allocable. As a separate promise under the terms of the Pierre Fabre Agreement, the Company is obligated to supply Pierre Fabre with the licensed product in accordance with the related supply agreement.   The Company is also obligated to participate in a Joint Steering Committee and Transition Plan, which were identified as separate performance obligations. To determine the respective stand-alone selling prices, the Company estimated the transaction prices, including any variable consideration, at contract inception and determined the fair value of such obligations based on similar arrangements. When determining the transaction prices, the Company assumed that the goods or services will be transferred to the customer based on the terms of the existing contract, and did not take into consideration the possibility of a contract being canceled, renewed, or modified. The Company noted there was approximately $9.0 million of additional variable consideration in this agreement related to a post-marketing commitment liability, while there were no significant financing components, non-cash consideration, or consideration payable to the customer. The Pierre Fabre Agreement also includes potential future milestone and royalty payments due to the Company upon successful completion of certain separate, distinct performance obligations.   Pursuant to the Pierre Fabre Agreement, the Company will potentially receive additional regulatory and commercial milestone payments totaling up to $345 million. In addition, the Company will receive significant double-digit royalties on NERLYNX sales throughout the territory covered by the Pierre Fabre Agreement . At this time, the Company cannot estimate when these milestone-related performance obligations are expected to be achieved.

Reserves for Variable Consideration:

Revenue from product sales are recorded at the net sales price (transaction price), which includes estimates of variable consideration for which reserves are established. Components of variable consideration include trade discounts and allowances, product returns, provider chargebacks and discounts, government rebates, payor rebates, and other incentives, such as voluntary patient assistance, and other allowances that are offered within contracts between the Company and its customers, payors, and other indirect customers relating to the Company’s sale of its products. These reserves, as detailed below, are based on the related sales, and are classified as reductions of accounts receivable or as a current liability. These estimates take into consideration a range of possible outcomes that are probability-weighted in accordance with the expected value method in ASC Topic 606 for relevant factors such as current contractual and statutory requirements, specific known market events and trends, industry data, and forecasted customer buying and payment patterns. Overall, these reserves reflect the Company’s best estimates of the amount of consideration to which it is entitled based on the terms of the respective underlying contracts.

The amount of variable consideration that is included in the transaction price may be constrained, and is included in the net sales price only to the extent that it is probable that a significant reversal in the amount of the cumulative revenue recognized under the contract will not occur in a future period. The Company’s analyses also contemplated application of the constraint in accordance with the guidance, under which it determined a material reversal of revenue would not occur in a future period for the estimates detailed below as of March 31, 2019 and, therefore, the transaction price was not reduced further during the quarter ended March 31, 2019. Actual amounts of consideration ultimately received may differ from the Company’s estimates. If actual results in the future vary from the Company’s estimates, the Company will adjust these estimates, which would affect net product revenue and earnings in the period such variances become known.

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Trade Discounts and Allowances:

The Company generally provides customers with discounts, which include incentive fees that are explicitly stated in the Company’s contracts and are recorded as a reduction of revenue in the period the related product revenue is recognized. The reserve for discounts is established in the same period that the related revenue is recognized, together with reductions to trade receivables, net on the consolidated balance sheets. In addition, the Company compensates its customers for sales order management, data, and distribution services. The Company has determined such services received to date are not distinct from the Company’s sale of products to its customers and, therefore, these payments have been recorded as a reduction of revenue within the statement of operations and comprehensive loss through March 31, 2019.

Product Returns:

Consistent with industry practice, the Company offers the specialty pharmacies and specialty distributors that are its customers limited product return rights for damaged and expiring product, provided it is within a specified period around the product expiration date as set forth in the applicable individual distribution agreement. The Company estimates the amount of its product sales that may be returned by its customers and records this estimate as a reduction of revenue in the period the related product revenue is recognized, as well as a reduction to trade receivables, net on the consolidated balance sheets. The Company currently estimates product returns using available industry data and its own sales information, including its visibility into the inventory remaining in the distribution channel. The Company has an insignificant amount of returns to date and believes that returns of its products will continue to be minimal.

Provider Chargebacks and Discounts:

Chargebacks for fees and discounts to providers represent the estimated obligations resulting from contractual commitments to sell products to qualified healthcare providers at prices lower than the list prices charged to its customers who directly purchase the product from the Company. Customers charge the Company for the difference between what they pay for the product and the ultimate selling price to the qualified healthcare providers. The reserve for chargebacks is established in the same period that the related revenue is recognized, resulting in a reduction of product revenue and the establishment of a current liability. Chargeback amounts are generally determined at the time of resale to the qualified healthcare provider by customers, and the Company generally issues payments for such amounts within a few weeks of the customer’s notification to the Company of the resale. Reserves for chargebacks consist of payments the Company expects to issue for units that remain in the distribution channel at each reporting period-end that the Company expects will be sold to qualified healthcare providers and chargebacks that customers have claimed, but for which the Company has not yet issued a payment .

Government Rebates:

The Company is subject to discount obligations under state Medicaid programs and Medicare. These reserves are recorded in the same period the related revenue is recognized, resulting in a reduction of product revenue and the establishment of a current liability, which is included in accrued expenses and other current liabilities on the consolidated balance sheets. The Company’s liability for these rebates consists of invoices received for claims from prior quarters that have not been paid or for which an invoice has not yet been received, estimates of claims for the current quarter, and estimates of future claims that will be made for product that has been recognized as revenue, but which remains in the distribution channel at the end of each reporting period.

Payor Rebates:

The Company contracts with certain private payor organizations, primarily insurance companies and pharmacy benefit managers, for the payment of rebates with respect to utilization of its products. The Company estimates these rebates and records such estimates in the same period the related revenue is recognized, resulting in a reduction of product revenue and the establishment of a current liability.

Other Incentives:

Other incentives the Company offers include voluntary patient assistance programs, such as the co-pay assistance program, which are intended to provide financial assistance to qualified commercially-insured patients with prescription drug co-payments required by payors. The calculation of the accrual for co-pay assistance is based on an estimate of claims and the cost per claim that the Company expects to receive associated with product that has been recognized as revenue, but remains in the distribution channel at the end of each reporting period. The adjustments are recorded in the same period the related revenue is recognized, resulting in a reduction of product revenue and the establishment of a current liability, which is included as a component of accrued expenses and other current liabilities on the consolidated balance sheets.

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Assets Measured at Fair Value on a Recurring Basis:

ASC, 820, Fair Value Measurement , or ASC 820, provides a single definition of fair value and a common framework for measuring fair value as well as new disclosure requirements for fair value measurements used in financial statements. Under ASC 820, fair value is determined based upon the exit price that would be received by a company to sell an asset or paid by a company to transfer a liability in an orderly transaction between market participants, exclusive of any transaction costs. Fair value measurements are determined by either the principal market or the most advantageous market. The principal market is the market with the greatest level of activity and volume for the asset or liability. Absent a principal market to measure fair value, the Company uses the most advantageous market, which is the market from which the Company would receive the highest selling price for the asset or pay the lowest price to settle the liability, after considering transaction costs. However, when using the most advantageous market, transaction costs are only considered to determine which market is the most advantageous and these costs are then excluded when applying a fair value measurement. ASC 820 creates a three-level hierarchy to prioritize the inputs used in the valuation techniques to derive fair values. The basis for fair value measurements for each level within the hierarchy is described below, with Level 1 having the highest priority and Level 3 having the lowest.

Following are the major categories of assets measured at fair value on a recurring basis as of March 31, 2019 and December 31, 2018, using quoted prices in active markets for identical assets (Level 1), significant other observable inputs (Level 2), and significant unobservable inputs (Level 3) (in thousands):

The Company’s investments in commercial paper, corporate bonds and U.S. government securities are exposed to price fluctuations. The fair value measurements for commercial paper, corporate bonds and U.S. government securities are based upon the quoted prices of similar items in active markets multiplied by the number of securities owned.

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The following tables summarize the Company’s short-term investments (in thous ands):

Concentration of Risk:

Financial instruments, which potentially subject the Company to concentrations of credit risk, principally consist of cash and cash equivalents and accounts receivable. The Company’s cash and cash equivalents and restricted cash in excess of the Federal Deposit Insurance Corporation and the Securities Investor Protection Corporation insured limits at March 31, 2019, were approximately $56.1 million. The Company does not believe it is exposed to any significant credit risk due to the quality nature of the financial instruments in which the money is held. Pursuant to the Company’s internal investment policy, investments must be rated A-1/P-1 or better by Standard and Poor’s Rating Service and Moody’s Investors Service at the time of purchase.

The Company sells its products in the United States primarily through specialty pharmacies and specialty distributors. Therefore, wholesale distributors and large pharmacy chains account for a large portion of its trade receivables and net product revenues. The creditworthiness of its customers is continuously monitored, and the Company has internal policies regarding customer credit limits. The Company estimates an allowance for doubtful accounts primarily based on the credit worthiness of our customers, historical payment patterns, aging of receivable balances and general economic conditions.

The Company’s success depends on its ability to successfully commercialize NERLYNX.  The Company currently has a single product with limited commercial sales experience, which makes it difficult to evaluate its current business, predict its future prospects and forecast financial performance and growth. The Company has invested a significant portion of its efforts and financial resources in the development and commercialization of the lead product, NERLYNX, and expects NERLYNX to constitute the vast majority of product revenue for the foreseeable future. The Company’s success depends on its ability to effectively commercialize NERLYNX.

The Company relies exclusively on third parties to formulate and manufacture NERLYNX and its drug candidates. The commercialization of NERLYNX and any other drug candidates, if approved, could be stopped, delayed or made less profitable if those third parties fail to provide sufficient quantities of product or fail to do so at acceptable quality levels or prices. The Company has no experience in drug formulation or manufacturing and does not intend to establish its own manufacturing facilities. The Company lacks the resources and expertise to formulate or manufacture NERLYNX and other drug candidates. While the drug candidates were being developed by Pfizer, both the drug substance and drug product were manufactured by third-party contractors. The Company is using the same third-party contractors to manufacture, supply, store and distribute drug supplies for clinical trials and the commercialization of NERLYNX. If the Company is unable to continue its relationships with one or more of these third-party contractors, it could experience delays in the development or commercialization efforts as it locates and qualifies new manufacturers. The Company intends to rely on one or more third-party contractors to manufacture the commercial supply of drugs.

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Research and Development Expenses:

Research and development expenses, or R&D, are charged to operations as incurred. The major components of research and development costs include clinical manufacturing costs, clinical trial expenses, consulting and other third-party costs, salaries and employee benefits, stock-based compensation expense, supplies and materials, and allocations of various overhead costs. Clinical trial expenses include, but are not limited to, investigator fees, site costs, comparator drug costs, and clinical research organization, or CRO, costs. In the normal course of business, the Company contracts with third parties to perform various clinical trial activities in the ongoing development of potential products. The financial terms of these agreements are subject to negotiation and variations from contract to contract and may result in uneven payment flows. Payments under the contracts depend on factors such as the achievement of certain events, the successful enrollment of patients and the completion of portions of the clinical trial or similar conditions. The Company’s accruals for clinical trials are based on estimates of the services received and efforts expended pursuant to contracts with numerous clinical trial sites, cooperative groups and CROs. As actual costs become known, the Company adjusts its accruals in that period.

In instances where the Company enters into agreements with third parties for clinical trials and other consulting activities, upfront amounts are recorded to prepaid expenses and other in the accompanying Consolidated Balance Sheets and expensed as services are performed or as the underlying goods are delivered. If the Company does not expect the services to be rendered or goods to be delivered, any remaining capitalized amounts for non-refundable upfront payments are charged to expense immediately. Amounts due under such arrangements may be either fixed fee or fee for service, and may include upfront payments, monthly payments and payments upon the completion of milestones or receipt of deliverables.

Costs related to the acquisition of technology rights and patents for which development work is still in process are charged to operations as incurred and considered a component of research and development costs.

Stock-Based Compensation:

Stock option awards:

ASC 718, Compensation-Stock Compensation , or ASC 718, requires the fair value of all share-based payments to employees, including grants of stock options, to be recognized in the statement of operations over the requisite service period. Under ASC 718, employee option grants are generally valued at the grant date and those valuations do not change once they have been established. The fair value of each option award is estimated on the grant date using the Black-Scholes Option Pricing Method. As allowed by ASC 718, the Company’s estimate of expected volatility is based on its average volatilities using its past six years of publicly traded history.  Beginning in 2018, the Company estimated its expected volatility based on its average volatilities using its past six years of publicly traded stock history, including industry, stage of life cycle, size and financial leverage. The risk-free rate for periods within the contractual life of the option is based on the U.S. Treasury yield curve in effect at the time of grant valuation. Option forfeitures are calculated when the option is granted to reduce the option expense to be recognized over the life of the award and updated upon receipt of further information as to the amount of options expected to be forfeited. The option expense is “trued-up” upon the actual forfeiture of a stock option grant. Due to its limited history of stock option exercises, the Company uses the simplified method to determine the expected life of the option grants.

Restricted stock units:

Restricted stock units, or RSUs, are valued on the grant date and the fair value of the RSUs is equal to the market price of the Company’s common stock on the grant date.  The RSU expense is recognized over the requisite service period.  When the requisite service period begins prior to the grant date (because the service inception date occurs prior to the grant date), the Company is required to begin recognizing compensation cost before there is a measurement date (i.e., the grant date).  The service inception date is the beginning of the requisite service period.  If the service inception date precedes the grant date, accrual of compensation cost for periods before the grant date shall be based on the fair value of the award at the reporting date.  In the period in which the grant date occurs, cumulative compensation cost shall be adjusted to reflect the cumulative effect of measuring compensation cost based on fair value at the grant date rather than the fair value previously used at the service inception date (or any subsequent reporting date).

Income Taxes:

The Company follows ASC 740, Income Taxes, or ASC 740, which requires recognition of deferred tax assets and liabilities for the expected future tax consequences of events that have been included in the consolidated financial statements or tax returns. Under this method, deferred tax assets and liabilities are based on the differences between the consolidated financial statement and tax basis of assets and liabilities using enacted tax rates in effect for the year in which the differences are expected to reverse. Deferred tax assets are reduced by a valuation allowance to the extent management concludes it is more likely than not that the asset will not be realized. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled.

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The standard addresses the determination of whether tax benefits claimed or expected to be claimed on a tax return should be recorded in the consolidated financial statements. Under ASC 740, the Company may recognize the tax benefit from an uncertain tax position only if it is more likely than not that the tax position will be sustained on examination by the tax authorities, based on the technical merits of the position. The tax benefits recognized in the consolidated financial statements from such a position should be measured based on the largest benefit that has a greater than 50% likelihood of being realized upon ultimate settlement. ASC 740 also provides guidance on de-recognition, classification, interest and penalties on income taxes, accounting in interim periods and requires increased disclosures. As of March 31, 2019, the Company has established a reserve of 20% of its research and development (“R&D”) credit carryover balance.  

Segment Reporting:

Management has determined that the Company operates in one business segment, which is the development and commercialization of innovative products to enhance cancer care.

Net Loss per Common Share:

Basic net loss per share of common stock is computed by dividing net loss applicable to common stockholders by the weighted average number of shares of common stock outstanding during the periods presented, as required by ASC 260, Earnings per Share . For purposes of calculating diluted loss per share of common stock, the denominator includes both the weighted average number of shares of common stock outstanding and the number of dilutive common stock equivalents, such as stock options, RSUs and warrants. A common stock equivalent is not included in the denominator when calculating diluted earnings per common share if the effect of such common stock equivalent would be anti-dilutive. For the quarter ended March 31, 2019, potentially dilutive securities excluded from the calculations were 5,554,070 shares issuable upon exercise of options, 2,116,250 shares issuable upon exercise of a warrant, and 1,698,146 shares underlying RSUs that were subject to vesting and were antidilutive. For the quarter ended March 31, 2018, potentially dilutive securities excluded from the calculations were 6,163,307 shares issuable upon exercise of options, 2,116,250 shares issuable upon exercise of a warrant, and 1,612,321 shares underlying RSUs that were subject to vesting and were antidilutive.  

Recently Adopted Accounting Standards:

In February 2016, the FASB issued ASU No. 2016-02, Leases . The amendments in ASU 2016-02 require organizations that lease assets, with lease terms of more than 12 months, to recognize on their balance sheet the assets and liabilities for the rights and obligations created by those leases. Consistent with GAAP, the recognition, measurement, and presentation of expenses and cash flows arising from a lease by a lessee primarily depends on its classification as a finance or operating lease. However, unlike previous GAAP that requires only capital leases to be recognized on the balance sheet, ASU No. 2016-02 requires both types of leases to be recognized on the balance sheet.  ASU 2016-02 is effective for fiscal years beginning after December 15, 2018, including interim periods within those fiscal years. For lessees, the income statement presentation and expense recognition pattern for financing and operating leases is similar to the current model for capital and operating leases, respectively. Companies may elect to exclude short-term leases. The update also requires additional disclosures that will better enable users of financial statements to assess the amount, timing, and uncertainty of cash flows arising from leases. The Company adopted ASU No. 2016-02 in the first quarter of 2019 using the effective date transition method. As permitted under the effective date transition method, financial information and disclosure for periods prior to the date of initial application will not be updated.  The adoption of ASU No. 2016-02 resulted in an increase in its assets and liabilities on its consolidated balance sheets related to recording right-of-use assets and corresponding lease liabilities of approximately $21.6 million and $27.4 million, respectively. The difference between the additional lease assets and lease liabilities represent deferred rent for leases that existed as of the date of adoption. As a result of the adoption there was no material impact to the consolidated statement of operations or statement of cash flows.

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Accounts receivable consists entirely of amounts owed from our customers related to product sales. The license revenue receivable relates to amounts owed from Pierre Fabre relating to license revenue recognized during the first quarter of 2019.

Other prepaid amounts consist primarily of deposits, licenses, subscriptions, software, and professional fees.

Other current asset amounts consist primarily of insurance reimbursements related to various lawsuits to which the Company is a party, and to a tenant improvement receivable.

Note 6—Leases:

           Components of lease expense include fixed lease expense and variable lease expense of approximately $1.2 million and $0.1 million, respectively, for the three months ended March 31, 2019. For purposes of determining straight-line rent expense, the lease term is calculated from the date the Company first takes possession of the facility, including any periods of free rent and any renewal option periods that the Company is reasonably certain of exercising. Our office and equipment leases generally have contractually specified minimum rent and annual rent increases are included in the measurement of the right-of-use asset and related lease liability. Additionally, under these lease arrangements, we may be required to pay directly, or reimburse the lessors, for real estate taxes, insurance, utilities, maintenance and other operating costs. Such amounts are generally variable and therefore not included in the measurement of the ROU asset and related lease liability but are instead recognized as variable lease expense in our Consolidated Statements of Income when they are incurred.

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Accrued CRO services, accrued other clinical development expenses, and accrued legal fees represent the Company’s estimates of such costs. Accrued compensation includes sales commissions and vacation.  Accrued royalties represent royalties incurred in connection with the Company’s license agreement with Pfizer.  Accrued compensation includes accrued bonuses and accrued vacation, which is accrued at the rate the employee earns vacation and reduced as vacation is used by the employee.    

Accrued variable consideration represents estimates of adjustments to net revenue for which reserves are established. Other accrued expenses consist primarily of accrued contractor/consultant costs, business license fees, taxes, insurance, and marketing fees.  

Accrued legal verdict expense represents an initial estimate of a range between $9.0 million and $18.0 million that may be owed to class action participants as a result of the recent jury verdict in Hsu v. Puma Biotechnology, Inc., and an initial estimate of $22.4 million that may be owed to the plaintiff as a result of the recent jury verdict in Eshelman v. Puma Biotechnology, Inc., et al .   The total amount of aggregate class-wide damages in Hsu is uncertain and will be ascertained only after an extensive claims process and the exhaustion of any appeals.  It is also reasonably possible that the total damages will be higher than this estimate.  

All accrued expenses are adjusted in the period the actual costs become known.  

In October 2017, the Company entered into a loan and security agreement with SVB, as administrative agent, and the lenders party thereto from time to time, including Oxford and SVB. Pursuant to the terms of the credit facility provided for by the loan and security agreement, the Company borrowed $50.0 million.

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In May 2018, the Company entered into an amendment to the loan and security agreement. Under the amended credit facility, the lenders agre ed to make term loans available to the Company in an aggregate amount of $ 155.0  million, consisting of (i) an aggregate amount of $ 125.0  million, the proceeds of which, in part, were used to repay the $ 50.0 million borrowed under the original credit facili ty, and (ii) an aggregate amount of $ 30.0  million that the Company drew in December 2018, which was available to under the credit facility as a result of achieving a specified minimum revenue milestone. Proceeds from the term loans under the amended credit facility may be used for working capital and general business purposes. Upon entry into the amended credit facility, the Company was required to pay the lenders aggregate fees of $ 4.2 million , consisting of a first amendment facility fee of $ 0.4 million a nd a final payment of $ 3.8 million in connection with the repayment of the $50.0 million borrowed under the original credit facility. The amended credit facility is secured by substantially all of the Company’s personal property other than its intellectual property. The Company also pledged 65 % of the issued and outstanding capital stock of its subsidiary, Puma Biotechnology Ltd.

The term loans under the amended credit facility bear interest at an annual rate equal to the greater of (i) 8.25% and (ii) the sum of (a) the “prime rate,” as reported in The Wall Street Journal on the last business day of the month that immediately precedes the month in which the interest will accrue, plus (b) 3.5%. The Company is required to make monthly interest-only payments on each term loan commencing on the first calendar day of the calendar month following the funding date of such term loan, and continuing on the first calendar day of each calendar month thereafter through July 1, 2020. Commencing on July 1, 2020, and continuing on the first calendar day of each calendar month thereafter, the Company will make consecutive equal monthly payments of principal, together with applicable interest, in arrears to each lender, calculated pursuant to the amended credit facility. All unpaid principal and accrued and unpaid interest with respect to each term loan is due and payable in full on May 1, 2023. Upon repayment of the term loans, the Company is also required to make a final payment to the lenders equal to 7.5% of the original principal amount of term loans funded.

At the Company’s option, the Company may prepay the outstanding principal balance of any term loan in whole but not in part, subject to a prepayment fee of 3.0% of any amount prepaid if the prepayment occurs through and including the first anniversary of the funding date of such term loan, 2.0% of any amount prepaid if the prepayment occurs after the first anniversary of the funding date of such term loan through and including the second anniversary of the funding date of such term loan, and 1.0% of the amount prepaid if the prepayment occurs after the second anniversary of the funding date of such term loan and prior to May 1, 2023.

The amended credit facility includes affirmative and negative covenants applicable to the Company, its current subsidiary and any subsidiaries the Company creates in the future. The affirmative covenants include, among others, covenants requiring the Company to maintain its legal existence and governmental approvals, deliver certain financial reports, maintain insurance coverage and satisfy certain requirements regarding deposit accounts. In accordance with these covenants, the Company must also achieve certain product revenue targets, measured as of the last day of each fiscal quarter on a trailing 3-month basis that is greater than or equal to 50% of the Company’s revenue target,    set forth in its board-approved projections for the 2019 fiscal year. New minimum revenue levels will be established for each subsequent fiscal year by mutual agreement of the Company, SVB as administrative agent, and the lenders. The negative covenants include, among others, restrictions on the Company’s transferring collateral, incurring additional indebtedness, engaging in mergers or acquisitions, paying dividends or making other distributions, making investments, creating liens, selling assets and suffering a change in control, in each case subject to certain exceptions.

The amended credit facility also includes events of default, the occurrence and continuation of which could cause interest to be charged at the rate that is otherwise applicable plus 5.0% and would provide SVB, as collateral agent, with the right to exercise remedies against the Company and the collateral securing the amended credit facility, including foreclosure against the property securing the credit facilities, including its cash. These events of default include, among other things, the Company’s failure to pay principal or interest due under the amended credit facility, a breach of certain covenants under the amended credit facility, the Company’s insolvency, a material adverse change, the occurrence of any default under certain other indebtedness in an amount greater than $0.5 million and one or more judgments against the Company in an am ount greater than $0.5 million individually or in the aggregate that remains unsatisfied, unvacated, or unstayed for a period of 10 days after its entry .

As of March 31, 2019, there was $155 million in term loans outstanding under the amended credit facility, and the Company was in compliance with all applicable covenants under the amended credit facility.

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Note 11—Stockholders’ Equity:

Common Stock:

The Company issued 56,125 and 72,571   shares of common stock upon exercise of stock options during the quarters ended March 31, 2019 and 2018, respectively. The Company issued 192,912 and 96,347   shares of common stock upon vesting of RSUs during the quarters ended March 31, 2019 and 2018 respectively.

Authorized Shares:

The Company has 100,000,000 shares of stock authorized for issuance, all of which   are common stock, par value $0.0001 per share.     

Warrants:

In October 2011, the Company issued an anti-dilutive warrant to Alan Auerbach, the Company’s founder and chief executive officer. The warrant was issued to provide Mr. Auerbach with the right to maintain ownership of at least 20% of the Company’s common stock in the event that the Company raised capital through the sale of its securities in the future.

In connection with the closing of a public offering in October 2012, the exercise price and number of shares underlying the warrant issued to Mr. Auerbach were established and, accordingly, the final value of the warrant became fixed. Pursuant to the terms of the warrant, Mr. Auerbach may exercise the warrant to acquire 2,116,250 shares of the Company’s common stock at $16 per share until October 4, 2021.

Stock Options and Restricted Stock Units:

The Company’s 2011 Incentive Award Plan, as amended, or the 2011 Plan, was adopted by the Company’s board of directors on September 15, 2011. Pursuant to the 2011 Plan, the Company may grant incentive stock options and nonqualified stock options, as well as other forms of equity-based compensation. Incentive stock options may be granted only to employees, while consultants, employees, officers and directors are eligible for the grant of nonqualified options under the 2011 Plan. The maximum term of stock options granted under the 2011 Plan is 10 years. The exercise price of incentive stock options granted under the 2011 Plan must be at least equal to the fair value of such shares on the date of grant. Through March 31, 2019, a total of 12,529,412 shares of the Company’s common stock had been reserved for issuance under the 2011 Plan.   

As of March 31, 2019, 6,867,528 shares of the Company’s common stock are issuable upon the exercise of outstanding awards granted under the 2011 Plan and 2,421,698 shares of the Company’s common stock are available for future issuance under the 2011 Plan. The fair value of options granted to employees was estimated using the Black-Scholes Option Pricing Method (see Note 2) with the following weighted-average assumptions used during the three months ended March 31, 2019 and 2018:  

The Company’s 2017 Employment Inducement Incentive Award Plan, or the 2017 Plan, was adopted by the Company’s Board of Directors on April 27, 2017.   Pursuant to the 2017 Plan, the Company may grant stock options and restricted stock units, as well as other forms of equity-based compensation to employees, as an inducement to join the Company.  The maximum term of stock options granted under the 2017 Plan is 10 years. The exercise price of stock options granted under the 2017 Plan must be at least equal to the fair market value of such shares on the date of grant. As of March 31, 2019, a total of 1,000,000 shares of the Company’s common stock have been reserved for issuance under the 2017 Plan.  As of March 31, 2019, 374,688 shares have been awarded under the 2017 Plan.

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Stock-based compensation was as follows for the three months ended March 31 (in thousands):

The fair value of options granted to employees was estimated using the Black-Scholes Option Pricing Method (see Note 2 –Significant Accounting Policies) with the following weighted-average assumptions used during the three months ended March 31, 2019 and 2018.

Activity with respect to options granted under the 2011 Plan and 2017 Plan is summarized as follows:

At March 31, 2019, total estimated unrecognized employee compensation cost related to non-vested stock options granted prior to that date was approximately $16.9 million, which is expected to be recognized over a weighted-average period of 1.6 years. At March 31, 2019, the total estimated unrecognized employee compensation cost related to non-vested RSUs was approximately $73.3 million, which is expected to be recognized over a weighted-average period of 1.9 years.  The weighted-average grant date fair value of options granted during the three months ended March 31, 2019 and 2018 was $21.82 and $56.46 per share, respectively.  The weighted average grant date fair value of RSUs awarded during the three months ended March 31, 2019 was $28.69 and $72.43 per share, respectively.      

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Note 12—401(k) Savings Plan:

The Company maintains a 401(k) savings plan for the benefit of its employees. The Company is required to make matching contributions to the 401(k) plan equal to 100% of the first 3% of wages deferred by each participating employee and 50% on the next 2% of wages deferred by each participating employee. The Company incurred expenses for employer matching contributions of approximately $0.4 million and $0.5 million   for the three months ended March 31, 2019 and 2018, respectively.

Note 13—Commitments and Contingencies:

Contractual Obligations:

Contractual obligations represent future cash commitments and liabilities under agreements with third parties, and exclude contingent liabilities for which the Company cannot reasonably predict future payment. The Company’s contractual obligations result primarily from obligations for various contract manufacturing organizations and clinical research organizations, which include potential payments we may be required to make under our agreements.  The contracts also contain variable costs and milestones that are hard to predict as they are based on such things as patients enrolled and clinical trial sites. The timing of payments and actual amounts paid under contract manufacturing organization, or CMO, and CRO agreements may be different depending on the timing of receipt of goods or services or changes to agreed-upon terms or amounts for some obligations.  Also, those agreements are cancelable upon written notice by the Company and, therefore, not long-term liabilities.

License Agreement:

In August 2011, the Company entered into an agreement pursuant to which Pfizer agreed to grant it a worldwide license for the development, manufacture and commercialization of PB272 neratinib (oral), PB272 neratinib (intravenous) and PB357, and certain related compounds. The license is exclusive with respect to certain patent rights owned by or licensed to Pfizer. Under the agreement, the Company is obligated to commence a new clinical trial for a product containing one of these compounds within a specified period of time and to use commercially reasonable efforts to complete clinical trials and to achieve certain milestones as provided in a development plan. From the closing date of the agreement through December 31, 2011, Pfizer continued to conduct the existing clinical trials on behalf of the Company at the Licensor’s sole expense. At the Company’s request, Pfizer has agreed to continue to perform certain services in support of the existing clinical trials at the Company’s expense. These services will continue through the completion of the transitioned clinical trials. The license agreement “capped” the out of pocket expense the Company would be responsible for completing the then existing clinical trials. All agreed upon costs incurred by the Company above the “cost cap” would be reimbursed by Pfizer. The Company exceeded the “cost cap” during the fourth quarter of 2012. In accordance with the license agreement, the Company billed Pfizer for agreed upon costs above the “cost cap” until December 31, 2013.

On July 18, 2014, the Company entered into an amendment to the license agreement with Pfizer. The amendment amends the agreement to (1) reduce the royalty rate payable by the Company to Pfizer on sales of licensed products; (2) release Pfizer from its obligation to pay for certain out-of-pocket costs incurred or accrued on or after January 1, 2014 to complete certain ongoing clinical studies; and (3) provide that Pfizer and the Company will continue to cooperate to effect the transfer to the Company of certain records, regulatory filings, materials and inventory controlled by Pfizer as promptly as reasonably practicable.

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As consideration for the license, the Company is required to make substantial payments upon the achievement of certain milestones totaling approximately $187.5 million if all such milestones are achieved. In connection with the FDA approval of NERLYNX in July of 2017, the Company triggered a one-time milestone payment pursuant to the agreement. Should the Company commercialize any more of the compounds lic ensed from Pfizer or any products containing any of these compounds, the Company will be obligated to pay to Pfizer annual royalties at a fixed rate in the low-to-mid teens of net sales of all such products, subject to certain reductions and offsets in som e circumstances. The Company’s royalty obligation continues, on a product-by-product and country-by-country basis, until the later of (1) the last to expire licensed patent covering the applicable licensed product in such country, or (2) the earlier of gen eric competition for such licensed product reaching a certain level in such country or expiration of a certain time period after first commercial sale of such licensed product in such country. In the event that the Company sublicenses the rights granted to the Company under the license agreement with Pfizer to a third party, the same milestone and royalty payments are required. The Company can terminate the license agreement at will, or for safety concerns, in each case upon specified advance notice.

Legal Proceedings

The Company and certain of its executive officers were named as defendants in the lawsuits detailed below.  The Company records a liability in the consolidated financial statements for loss contingencies when a loss is known or considered probable and the amount can be reasonably estimated. If the reasonable estimate of a known or probable loss is a range, and no amount within the range is a better estimate than any other, the minimum amount of the range is accrued. If a loss is reasonably possible but not known or probable, and can be reasonably estimated, the estimated loss or range of loss is disclosed. When determining the estimated loss or range of loss, significant judgment is required to estimate the amount and timing of a loss to be recorded.  Currently, the Company has accrued estimated losses of $9 million related to Hsu v. Puma Biotechnology, Inc. and $22.4 million related to Eshelman v. Puma Biotechnology, Inc., et al. as detailed below. .  For certain legal expenses related to the verdicts listed below, the Company receives reimbursements from its insurers.  Currently, the Company expects to receive $9.9 million in reimbursements, all of which have been deemed probable and estimable as of March 31, 2019.  

Hsu v. Puma Biotechnology, Inc.

On June 3, 2015, Hsingching Hsu, individually and on behalf of all others similarly situated, filed a class action lawsuit against the Company and certain of its executive officers in the United States District Court for the Central District of California (Case No. 8:15-cv-00865-AG-JCG).  On October 16, 2015, lead plaintiff Norfolk Pension Fund filed a consolidated complaint on behalf of all persons who purchased the Company’s securities between July 22, 2014 and May 29, 2015.   A trial on the claims relating to four statements alleged to have been false or misleading was held from January 15 to January 29, 2019. At trial, the jury found that three of the four challenged statements were not false or misleading, and thus found in the defendants’ favor on those claims.  The jury found liability as to one statement and awarded a maximum of $4.50 per share in damages, which represents approximately 5% of the total claimed damages of $87.20 per share.  The total amount of aggregate class-wide damages is uncertain and will be ascertained only after an extensive claims process and the exhaustion of any appeals.  Trading models suggest that approximately ten million shares traded during the class period may be eligible to claim damages.  Based on prior lawsuits, the Company believes that the number of stockholders who submit proof of claims sufficient to recover damages is typically in the range of 20% to 40% of the total eligible shares.  Based on these assumptions, total damages after claims could range from $9 million to $18 million.  It is also reasonably possible that the total damages will be higher than this estimate, however, at this time, the amount is not estimable.  A final judgment has not been entered.

Eshelman v. Puma Biotechnology, Inc., et al.

In February 2016, Fredric N. Eshelman filed a lawsuit against the Company’s Chief Executive Officer and President, Alan H. Auerbach, and the Company in the United States District Court for the Eastern District of North Carolina (Case No. 7:16-cv-00018-D).  The comp laint generally alleged that Mr. Auerbach and the Company made defamatory statements regarding Dr. Eshelman in connection with a proxy contest.  In May 2016, Dr. Eshelman filed a notice of voluntary dismissal of the claims against Mr. Auerbach.  A trial on the remaining defamation claims against the Company took place from March 11 to March 15, 2019.  At trial, the jury found the Company liable and awarded Dr. Eshelman $15.9 million in compensatory damages and $6.5 million in punitive damages.  The plaintiff has since filed motions seeking attorneys’ fees and prejudgment interest, which if granted could increase the judgment amount.  The Company strongly disagrees with the verdict and, on April 22, 2019, filed a motion for a new trial or, in the alternative, a reduced damages award.  If the verdict is upheld, pending the outcome of that motion, the Company intends to appeal the verdict.

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Derivative Actions  

On April 12 and April 14, 2016, stockholders filed two derivative lawsuits purportedly on behalf of the Company against certain of its officers and directors in the Superior Court of the State of California, Los Angeles, captioned Xie v. Auerbach , No. BC616617, and McKenney v. Auerbach , No. BC617059. The complaints asserted claims for breach of fiduciary duty, unjust enrichment, abuse of control, mismanagement and waste of corporate assets. McKenney was consolidated with Xie on June 21, 2016. The complaints sought an unspecified sum of damages and equitable relief.  

Separately, on February 9, 2018, another purported stockholder filed a derivative lawsuit purportedly on behalf of the Company against certain of our officers and directors in the United States District Court, Central District of California, captioned Van Der Gracht De Rommerswael v. Auerbach , No. 8:18-cv-00236.  The complaint asserted claims for violation of securities laws, breach of fiduciary duty, waste of corporate assets, and unjust enrichment.  

On May 30, 2018, another stockholder filed a derivative lawsuit purportedly on behalf of the Company against certain of its officers and directors in the United States District Court, Central District of California, captioned Duran v. Auerbach , No. 2:18-cv-04802.  The complaint asserted claims for violations of securities laws, breach of fiduciary duties, unjust enrichment, abuse of control, gross mismanagement, and waste of corporate assets.  The complaint seeks an unspecified sum of damages, declaratory judgment, corporate reforms, restitution, and costs and disbursements associated with the lawsuit. 

On July 30, 2018, the parties reached a settlement in principle of the Xie , Rommerswael and Duran lawsuits. On January 7, 2019, the Court approved the settlement and entered final judgment in the Rommerswael case.  On March 1, 2019, the Court approved the parties’ stipulation and dismissed the Duran lawsuit with prejudice.  On April 8, 2019, the Court approved the parties’ stipulation and dismissed the Xie lawsuit with prejudice.