Biggest changeWe expect to incur expenses as we: ● conduct our current and planned clinical trials for our current and future product candidates; ● increase clinical and commercial manufacturing capabilities or make arrangements with additional third party manufacturers to successfully manufacture our products and product candidates; ● develop and timely deliver clinical grade and commercial grade product formulations that can be used in our clinical trials and for commercial sale; ● seek regulatory approvals for any product candidates that successfully complete clinical trials; ● maintain, establish, and/or expand a sales, marketing, medical affairs and distribution infrastructure to commercialize ARCALYST or any of our current or future product candidates for which we may obtain marketing approval and intend to commercialize on our own; ● launch commercial sales of any of our current or future product candidates, if and when approved, whether alone or in collaboration with others; ● make milestone or other payments under any current or future license, acquisition, collaboration or other strategic transaction agreements; 135 Table of Contents ● expand our operational, financial and management systems and increase personnel globally to support our clinical development, manufacturing and commercialization efforts and our operations as a public company; ● maintain, expand and protect our intellectual property portfolio; and ● in-license or acquire other product candidates and technologies or their related businesses, if we determine to do so.
Biggest changeWe expect to incur expenses as we: ● support our sales, marketing and distribution capabilities, infrastructure and organization to commercialize ARCALYST and any product candidates for which we may obtain marketing approval; ● conduct new and ongoing research and pre-clinical and clinical development of our product candidates, including our Phase 2 clinical trial for abiprubart ; ● manufacture our products and product candidates for clinical or commercial use, increase our manufacturing capabilities, add additional manufacturers or suppliers and perform activities related to our technology transfer of the process for manufacturing ARCALYST drug substance; ● seek regulatory and marketing approvals for our product candidates that successfully complete clinical trials, if any; ● make milestone or other payments under any current or future license, acquisition, collaboration or other strategic transaction agreement; ● seek to identify, assess and study new or expanded indications for our products or product candidates, new or alternative dosing levels and frequency for our products or product candidates, or new or alternative administration of our products or product candidates, including method, mode or delivery device; ● seek to identify, assess, acquire or develop additional product candidates; ● enter into licensing, acquisition, collaboration or other strategic transaction agreements; ● seek to maintain, protect and expand our intellectual property portfolio; ● seek to attract and retain skilled personnel; ● create additional infrastructure to support our product development and commercialization efforts; and ● experience delays or encounter issues with any of the above, including but not limited to failed trials, complex results, safety issues, regulatory challenges that require longer follow-up of existing trials, additional major trials, additional supportive trials in order to pursue marketing approval, a pandemic or other outbreak of disease, or the global economic slowdown and rising inflation.
This process involves reviewing open contracts and purchase orders, communicating with our personnel to identify services that have been performed on our behalf and estimating the level of service performed and the associated cost incurred for the service when we have not yet been invoiced or otherwise notified of actual costs.
This process involves reviewing open contracts and purchase orders, communicating with our personnel to identify services that have been performed on our behalf and estimating the level of service performed and the associated cost incurred for the service when we have not yet been invoiced or otherwise notified of actual costs.
Deferred tax assets and liabilities are determined based on the difference between the 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. Changes in deferred tax assets and liabilities are recorded in the (provision) benefit for income taxes.
Deferred tax assets and liabilities are determined based on the difference between the 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. Changes in deferred tax assets and liabilities are recorded in the benefit (provision) for income taxes.
These expenses may include: ● expenses incurred to conduct the necessary preclinical studies and clinical trials required to obtain regulatory approval; ● expenses incurred under agreements with CROs that are primarily engaged in the oversight and conduct of our clinical trials and CMOs that are primarily engaged to provide preclinical and clinical drug substance and product for our research and development programs for our product candidates; ● other costs related to acquiring and manufacturing preclinical and clinical trial materials, including manufacturing validation batches, as well as investigative sites and consultants that conduct our clinical trials, preclinical studies and other scientific development services; ● payments made in cash or equity securities under third-party licensing, acquisition and other similar agreements; ● employee-related expenses, including salaries and benefits, travel and share-based compensation expense for employees engaged in research and development functions; ● costs related to compliance with regulatory requirements; and ● allocated facilities-related costs, which include rent and utilities, depreciation and other expenses.
These expenses may include: ● expenses incurred to conduct the necessary preclinical studies and clinical trials required to obtain regulatory approval; ● expenses incurred under agreements with CROs that are primarily engaged in the oversight and conduct of our clinical trials and CDMOs that are primarily engaged to provide preclinical and clinical drug substance and product for our research and development programs for our product candidates; ● other costs related to acquiring and manufacturing preclinical and clinical trial materials, including manufacturing validation batches, as well as investigative sites and consultants that conduct our clinical trials, preclinical studies and other scientific development services; ● payments made in cash or equity securities under third party licensing, acquisition and other similar agreements; ● employee-related expenses, including salaries and benefits, travel and share-based compensation expense for employees engaged in research and development functions; ● costs related to compliance with regulatory requirements; and ● allocated facilities-related costs, which include rent and utilities, depreciation and other expenses.
In addition, if we obtain regulatory approval for any of our current or future product candidates, pursue additional indications for our products or any of our current or future product candidates, we expect to incur significant expenses related to product development and manufacturing, sales, marketing and distribution, depending on where we choose to commercialize.
In addition, if we obtain regulatory approval for any of our current or future product candidates, pursue additional indications or additional territories for our products or any of our current or future product candidates, we expect to incur significant expenses related to product development and manufacturing, sales, marketing and distribution, depending on where we choose to commercialize.
Adjustments for variable consideration are determined based on the contractual terms with customers, historical trends, communications with customers and the levels of inventory remaining in the distribution channel, as well as expectations about the market for the product and anticipated introduction of competitive products. As of December 31, 2022, a 10% change in our product revenue allowance and reserve would not result in a material change in our net revenue. Accrued Research and Development Expenses As part of the process of preparing our consolidated financial statements, we are required to estimate our accrued research and development expenses.
Adjustments for variable consideration are determined based on the contractual terms with customers, historical trends, communications with customers and the levels of inventory remaining in the distribution channel, as well as expectations about the market for the product and anticipated introduction of competitive products. As of December 31, 2023, a 10% change in our product revenue allowance and reserve would not result in a material change in our net revenue. Accrued Research and Development Expenses As part of the process of preparing our consolidated financial statements, we are required to estimate our accrued research and development expenses.
ASC 606 also requires an entity to present a revenue contract as a contract liability in instances when a customer pays consideration, or an entity has a right to an amount of consideration that is unconditional (e.g. receivable), before the entity transfers a good or service to the customer. Product Revenue, Net Net revenue from product sales is recognized at the transaction price when the specialty pharmacy or specialty distributors obtains control of our products, which occurs at a point in time, typically upon shipment of the product from the third party logistics provider. Our net revenues represent total revenues adjusted for discounts and allowances, including estimated cash discounts, chargebacks, rebates, returns, copay assistance, and specialty pharmacy and distributor fees.
ASC 606 also requires an entity to present a revenue contract as a contract liability in instances when a customer pays consideration, or an entity has a right to an amount of consideration that is unconditional (e.g. receivable), before the entity transfers a good or service to the customer. 126 Table of Contents Product Revenue, Net Net revenue from product sales is recognized at the transaction price when the specialty pharmacy or specialty distributors obtains control of our products, which occurs at a point in time, typically upon shipment of the product from the third party logistics provider. Our net revenues represent total revenues adjusted for discounts and allowances, including estimated cash discounts, chargebacks, rebates, returns, copay assistance, and specialty pharmacy and distributor fees.
Our direct research and development expenses are tracked on a program-by-program basis for our product candidates and consist primarily of external costs, such as fees paid to outside consultants, CROs, CMOs and research laboratories in connection with our preclinical development, process development, manufacturing and clinical development activities.
Our direct research and development expenses are tracked on a program-by-program basis for our product candidates and consist primarily of external costs, such as fees paid to outside consultants, CROs, CDMOs and research laboratories in connection with our preclinical development, process development, manufacturing and clinical development activities.
Significant judgment is required in assessing both positive and negative evidence available and, to the extent that a reversal of any portion of our valuation allowance against our deferred tax assets is deemed appropriate, a tax benefit will be recognized against our income tax provision in the period of such reversal.
Significant judgment is required in assessing both positive and negative evidence available and, to the extent that a reversal of any portion of our valuation allowance against our deferred tax assets is deemed appropriate, a tax benefit will be recorded in our income tax benefit (provision) in the period of such reversal.
Financing Activities During the years ended December 31, 2022 and 2021, net cash provided by financing activities was $2.5 million and $5.9 million, respectively, consisting of proceeds from the exercise of employee share options and our 2018 Employee Share Purchase Plan (the “2018 ESPP”).
Financing Activities During the years ended December 31, 2023, 2022 and 2021, net cash provided by financing activities was $1.5 million, $2.5 million and $5.9 million, respectively, consisting of proceeds from the exercise of employee share options and our 2018 Employee Share Purchase Plan (the “2018 ESPP”).
Huadong will also be obligated to pay us tiered percentage royalties on a Huadong Licensed Product-by-Huadong Licensed Product basis ranging from the low-teens to low-twenties on annual net sales of each Huadong Licensed Product in the Huadong Territory, subject to certain reductions tied to rilonacept manufacturing costs and certain other customary reductions, with an aggregate minimum floor.
Huadong will also be obligated to pay us tiered percentage royalties on a Huadong Licensed Product-by-Huadong Licensed Product basis ranging from the low-teens to low-twenties on 116 Table of Contents annual net sales of each Huadong Licensed Product in the Huadong Territory, subject to certain reductions tied to rilonacept manufacturing costs and certain other customary reductions, with an aggregate minimum floor.
Such costs include but are not limited to (i) our cost of goods sold for product used, sold or otherwise distributed for patient use by us; (ii) customary commercialization expenses, including the cost of our field force, and (iii) our cost to market, advertise and otherwise promote ARCALYST, with such costs identified in subsection (iii) 127 Table of Contents subject to specified limits.
Such costs include but are not limited to (i) our cost of goods sold for product used, sold or otherwise distributed for patient use by us; (ii) customary commercialization expenses, including the cost of our field force, and (iii) our cost to market, advertise and otherwise promote ARCALYST, with such costs identified in subsection (iii) subject to specified limits.
Overview We are a biopharmaceutical company focused on discovering, acquiring, developing and commercializing therapeutic medicines for patients suffering from debilitating diseases with significant unmet medical need.
Overview We are a commercial-stage biopharmaceutical company focused on discovering, acquiring, developing and commercializing therapeutic medicines for patients suffering from debilitating diseases with significant unmet medical need.
ARCALYST is sold through a third party logistics provider that distributes primarily through a network of authorized specialty pharmacies and specialty distributors (collectively, “customers”), which deliver the medication to patients by mail. Net revenue from product sales is recognized at the transaction price when the specialty pharmacy or specialty distributors obtains control of our product, which occurs at a point in time, typically upon shipment of the product from the third party logistics provider. Our net revenues represent total revenues adjusted for discounts and allowances, including estimated cash discounts, chargebacks, rebates, returns, copay assistance, and specialty pharmacy and distributor fees.
ARCALYST is sold through a third party logistics provider that distributes primarily through a select network of specialty pharmacies (collectively, “customers”), which deliver the medication to patients by mail. Net revenue from product sales is recognized at the transaction price when the customer obtains control of our product, which occurs at a point in time, typically upon shipment of the product from the third party logistics provider. Our net revenues represent total revenues adjusted for discounts and allowances, including estimated cash discounts, chargebacks, rebates, returns, copay assistance, and specialty pharmacy and distributor fees.
Although we do not expect our estimates to be materially different from amounts actually incurred, our understanding of the status and timing of services performed relative to the actual status and timing of services performed may vary and may result in reporting amounts that are too high or too low in any particular period.
Although we do not expect our estimates to be materially different from amounts actually incurred, our understanding of the status and timing of services performed relative to the actual status and timing of services 127 Table of Contents performed may vary and may result in reporting amounts that are too high or too low in any particular period.
Recently Issued Accounting Pronouncements A description of recently issued accounting pronouncements that may potentially impact our financial position and results of operations is disclosed in Note 2 to our annual consolidated financial statements included elsewhere in this Annual Report. 138 Table of Contents I TEM 7A. QUANTITATIVE AND QUALITATIVE DISCLOSURES ABOUT MARKET RISK.
Recently Issued Accounting Pronouncements A description of recently issued accounting pronouncements that may potentially impact our financial position and results of operations is disclosed in Note 2 to our annual consolidated financial statements included elsewhere in this Annual Report. I TEM 7A. QUANTITATIVE AND QUALITATIVE DISCLOSURES ABOUT MARKET RISK.
Adjustments for variable consideration are determined based on the contractual terms with customers, historical trends, communications with customers and the levels of inventory remaining in the distribution channel, as well as expectations about the market for the product and anticipated introduction of competitive products. License and collaboration revenue License and collaboration revenue includes amounts recognized related to upfront payments, royalty revenue, and milestone payments. 126 Table of Contents In February 2022, we entered into the Huadong Collaboration Agreements, pursuant to which we granted Huadong exclusive rights to develop and commercialize the Huadong Licensed Products in the Huadong Territory.
Adjustments for variable consideration are determined based on the contractual terms with customers, historical trends, communications with customers and the levels of inventory remaining in the distribution channel, as well as expectations about the market for the product and anticipated introduction of competitive products. License and collaboration revenue License and collaboration revenue includes amounts recognized related to upfront payments, royalty revenue, milestone payments and products sold under collaboration agreements. In February 2022, we entered into the Huadong Collaboration Agreements, pursuant to which we granted Huadong exclusive rights to develop and commercialize the Huadong Licensed Products in the Huadong Territory.
We received FDA approval of ARCALYST for the treatment of recurrent pericarditis and reduction in risk of recurrence in adults and children 12 years and older in March 2021. Recurrent pericarditis is a painful inflammatory cardiovascular disease with an estimated U.S. prevalent population of approximately 40,000 patients seeking and receiving medical treatment.
We received FDA approval of ARCALYST for the treatment of recurrent pericarditis and reduction in risk of recurrence in adults and children 12 years and older in March 2021. Recurrent pericarditis is a painful inflammatory cardiovascular disease with an estimated United States prevalent population of approximately 40,000 patients seeking and receiving medical treatment.
We expect to incur operating losses for the foreseeable future as we advance our product candidates through preclinical and clinical development and, ultimately, seek regulatory approval. In addition, we expect to continue to incur significant expenses related to product manufacturing, including potential technology transfer costs as early as March 2023, marketing, sales and distribution of ARCALYST.
We expect to incur operating losses for the foreseeable future as we advance our product candidates through preclinical and clinical development and, ultimately, seek regulatory approval. In addition, we expect to continue to incur significant expenses related to product manufacturing, including technology transfer costs, marketing, sales and distribution of ARCALYST.
Examples of estimated accrued research and development expenses include fees paid to: 137 Table of Contents ● vendors, including research laboratories, in connection with preclinical development activities; ● CROs and investigative sites in connection with preclinical studies and clinical trials; ● third parties in the connection with the achievement of milestones due under license acquisition and other similar agreements; and ● CMOs in connection with drug substance and drug product formulation and manufacturing of materials.
Examples of estimated accrued research and development expenses include fees paid to: ● vendors, including research laboratories, in connection with preclinical development activities; ● CROs and investigative sites in connection with preclinical studies and clinical trials; ● third parties in the connection with the achievement of milestones due under license acquisition and other similar agreements; and ● CDMOs in connection with drug substance and drug product formulation and manufacturing of materials.
Because of the numerous risks and uncertainties associated with research, development and commercialization of biologic products, we are unable to estimate the exact amount of our working capital requirements. Our future funding requirements may be impacted by a number of factors, including those described in Part I, Item 1A. “Risk Factors” in this Annual Report.
Because of the numerous risks and uncertainties associated with research, development and commercialization of biologic products, we are unable to estimate the exact amount of our working capital requirements. Our future funding requirements may be impacted by a number of factors, including those described in Part I, Item 1A.
However, because of the short-term nature of the instruments in our portfolio, an immediate 10% change in market interest rates would not have a material impact on the fair market value of our investment portfolio or on our financial position or results of operations.
However, because of the short-term nature of the instruments in our portfolio, an immediate 100 basis point change in market interest rates would not have a material impact on the fair market value of our investment portfolio or on our financial position or results of operations.
The license and collaboration revenue for the year ended December 31, 2022 primarily consisted of $10.0 million in revenue recognized upon the signing of the mavrilimumab Huadong Collaboration Agreement in February of 2022 and $87.7 million for revenue related to the Genentech License Agreement.
We reported $97.7 million of license and collaboration revenue for the year ended December 31, 2022, which primarily consisted of $87.7 million for revenue related to the Genentech License Agreement and $10.0 million in revenue recognized upon the signing of the mavrilimumab Huadong Collaboration Agreement in February of 2022.
Our actual results may differ from these estimates under different assumptions or conditions. 136 Table of Contents While our significant accounting policies are described in more detail in Note 2 to our consolidated financial statements included elsewhere in this Annual Report, we believe that the following accounting policies are those most critical to the judgments and estimates used in the preparation of our consolidated financial statements. Revenue Recognition ASC 606 outlines a five-step process for recognizing revenue from contracts with customers: (i) identify the contract with the customer, (ii) identify the performance obligations in the contract, (iii) determine the transaction price, (iv) allocate the transaction price to the separate performance obligations in the contract, and (v) recognize revenue associated with the performance obligations as they are satisfied. We only apply the five-step model to contracts when it is probable that we will collect the consideration we are entitled to in exchange for the goods or services we transfer to the customer.
While our significant accounting policies are described in more detail in Note 2 to our consolidated financial statements included elsewhere in this Annual Report, we believe that the following accounting policies are those most critical to the judgments and estimates used in the preparation of our consolidated financial statements. Revenue Recognition ASC 606 outlines a five-step process for recognizing revenue from contracts with customers: (i) identify the contract with the customer, (ii) identify the performance obligations in the contract, (iii) determine the transaction price, (iv) allocate the transaction price to the separate performance obligations in the contract, and (v) recognize revenue associated with the performance obligations as they are satisfied. We only apply the five-step model to contracts when it is probable that we will collect the consideration we are entitled to in exchange for the goods or services we transfer to the customer.
The increase was due primarily to higher interest rates on U.S. Treasury notes and a higher average balance in short term investments. Other income was $0.1 million for the year ended December 31, 2021, compared to other income of $1.1 million for the year ended December 31, 2020. The decrease was due primarily to lower interest rates on U.S.
The increase was due primarily to higher interest rates on U.S. Treasury notes and a higher average balance in short term investments. Other income was $1.3 million for the year ended December 31, 2022, compared to other income of $0.1 million for the year ended December 31, 2021. The increase was due primarily to higher interest rates on U.S.
ARCALYST is commercially available across the United States through a network of distributors. ARCALYST is also approved in the United States for the treatment of CAPS, specifically Familial Cold Autoinflammatory Syndrome and Muckle-Wells Syndrome in adults and children 12 years and older, and the maintenance of remission in DIRA in adults and children weighing 10 kg or more.
ARCALYST is commercially available across the United States through a network of distributors. ARCALYST is also approved in the United States for the treatment of CAPS, including FCAS and Muckle-Wells Syndrome in adults and children 12 years and older, and the maintenance of remission in DIRA in adults and children weighing 10 kg or more.
The increase of $12.0 million in 2022 from 2021 was primarily due to an increase of $8.8 million in sales and marketing associated with the commercial operations of ARCALYST.
The increase of $12.0 million in 2022 from 2021 was primarily due to an increase of $8.8 million in sales and marketing associated with our first full year of commercial operations of ARCALYST.
Additionally, we expect to continue to incur costs associated with operating as a public company, including significant legal, accounting, investor relations and other expenses.
Additionally, we expect to continue to incur costs associated with operating as a public 124 Table of Contents company, including significant legal, accounting, investor relations and other expenses.
Collaboration expenses Collaboration expenses consists of Regeneron’s share of the profit related to ARCALYST sales under the Regeneron Agreement. We evenly split profits on sales of ARCALYST with Regeneron, where profits are determined after deducting from net sales of ARCALYST certain costs related to the manufacturing and commercialization of ARCALYST.
Collaboration expenses Collaboration expenses consist of Regeneron’s share of the profit related to ARCALYST sales under the Regeneron Agreement and the cost of products sold under collaboration agreements. We evenly split profits on sales of ARCALYST with Regeneron, where profits are determined after deducting from net sales of ARCALYST certain costs related to the manufacturing and commercialization of ARCALYST.
Personnel-related costs for the years ended December 31, 2022, 2021 and 2020 included share-based compensation of $6.8 million, $8.5 million and $8.9 million, respectively. Selling, General and Administrative Expenses Selling, general and administrative expenses were $98.0 million, $85.9 million and $45.3 million for the years ended December 31, 2022, 2021 and 2020.
Personnel-related costs for the years ended December 31, 2023, 2022 and 2021 included share-based compensation of $5.5 million, $6.8 million and $8.5 million, respectively. Selling, General and Administrative Expenses Selling, general and administrative expenses were $129.4 million, $98.0 million and $85.9 million for the years ended December 31, 2023, 2022 and 2021.
Personnel-related costs for the years ended December 31, 2022, 2021 and 2020 included share-based compensation of $17.7 million, $16.5 million and $12.0 million, respectively. Other Income Other income was $1.3 million for the year ended December 31, 2022, compared to other income of $0.1 million for the year ended December 31, 2021.
Personnel-related costs for the years ended December 31, 2023, 2022 and 2021 included share-based compensation of $19.8 million, $17.7 million and $16.5 million, respectively. Other Income Other income was $8.5 million for the year ended December 31, 2023, compared to other income of $1.3 million for the year ended December 31, 2022.
We use internal resources primarily to conduct our research and discovery activities as well as for managing our preclinical and clinical development, process development and manufacturing activities. 128 Table of Contents Research and development activities are central to our business.
We use internal resources primarily to conduct our research and discovery activities as well as for managing our preclinical and clinical development, process development and manufacturing clinical and preclinical materials. Research and development activities are central to our business.
We will be eligible to receive up to approximately $600.0 million in contingent payments, including specified development, regulatory and sales-based milestones as well as royalties in the low double digits to mid-teens on annual net sales, in each case before fulfilling our upstream financial obligations.
We will be eligible to receive up to a total of approximately $600.0 million in contingent payments, including specified development, regulatory and sales-based milestones, of which approximately $575.0 million remain as of December 31, 2023, as well as royalties in the low double digits to mid-teens on annual net sales, in each case before fulfilling our upstream financial obligations.
Interest Rate Risk We are exposed to market risk related to changes in interest rates. As of December 31, 2022, our cash, cash equivalents and short-term investments consisted of money market funds and U.S. Treasury notes.
Interest Rate Risk We are exposed to market risk related to changes in interest rates. As of December 31, 2023, our cash, cash equivalents and short-term investments consisted of money market funds and United States Treasury notes.
We may also incur expenses in connection with the in-licensing or acquisition of additional product candidates. As of December 31, 2022, we had cash, cash equivalents and short-term investments of $190.6 million.
We may also incur expenses in connection with the in-licensing or acquisition of additional product candidates. As of December 31, 2023, we had cash, cash equivalents and short-term investments of $206.4 million.
This uncertainty is due to the numerous risks and uncertainties, including those described in Part I, Item 1A.
This uncertainty is due to the numerous risks and uncertainties, including those described in Part I, Item 1A. “Risk Factors” in this Annual Report.
Our portfolio of immune-modulating assets, ARCALYST® (rilonacept), KPL-404 and mavrilimumab, are based on strong biologic rationale or validated mechanisms, target a spectrum of underserved cardiovascular and autoimmune conditions, and offer the potential for differentiation. ARCALYST is an interleukin-1α and interleukin-1β cytokine trap. In 2017, we licensed ARCALYST from Regeneron, who discovered and initially developed the drug.
Our portfolio of immune-modulating assets, ARCALYST® (rilonacept), abiprubart, and mavrilimumab, is based on strong biologic rationale or validated mechanisms, targets a spectrum of underserved cardiovascular and autoimmune conditions, and offers the potential for differentiation. ARCALYST is an interleukin-1α and interleukin-1β cytokine trap. In 2017, we licensed ARCALYST from Regeneron, which discovered and initially developed the drug.
Until such time, if ever, as we can generate substantial and sustained product revenue, we expect to finance our cash needs through a combination of public or private equity offerings, debt financings, or other sources, including, licensing, collaboration, marketing, distribution or other strategic transactions or arrangements with third parties.
“ Risk Factors ” in this Annual Report. 125 Table of Contents Until such time, if ever, as we can generate substantial and sustained product revenue, we expect to finance our cash needs through a combination of public or private equity offerings, debt financings, or other sources, including, licensing, collaboration, marketing, distribution or other strategic transactions or arrangements with third parties.
To date, there have not been any material adjustments to our prior estimates of accrued research and development expenses. As of December 31, 2022, we have accrued $8.4 million of estimated research and development expenses.
To date, there have not been any material adjustments to our prior estimates of accrued research and development expenses. As of December 31, 2023, we have accrued $7.9 million of estimated research and development expenses.
We are responsible for sales and distribution of ARCALYST in all approved indications in the United States, and evenly split profits on sales as well as third-party proceeds with Regeneron. In February 2022, we granted Huadong exclusive rights to develop and commercialize ARCALYST in the Asia Pacific region, excluding Japan. KPL-404 is an investigational monoclonal antibody inhibitor of CD40-CD154 interaction.
We are responsible for sales and distribution of ARCALYST in all approved indications in the United States, and evenly split profits on sales as well as third party proceeds with Regeneron. In February 2022, we granted Huadong exclusive rights to develop and commercialize ARCALYST in the Asia Pacific region, excluding Japan.
The CD40-CD154 interaction is a key T-cell co-stimulatory signal critical for B-cell maturation, immunoglobulin class switching and Type 1 immune response. We believe disrupting the CD40-CD154 interaction is an attractive approach to address multiple autoimmune disease pathologies such as RA, Sjogren’s syndrome, Graves’ disease and systemic lupus erythematosus.
The CD40-CD154 interaction is a key T-cell co-stimulatory signal critical for B-cell maturation, immunoglobulin class switching and Type 1 immune response. We believe disrupting the CD40-CD154 costimulatory interaction is an attractive approach to address multiple autoimmune disease pathologies.
During the year ended December 31, 2022, expenses related primarily to the wind-down activities of the Phase 3 portion of our clinical trial in COVID-19 related ARDS. During the year ended December 31, 2021, expenses primarily related to our Phase 2/3 clinical trial in COVID-19 related ARDS.
During the year ended December 31, 2023, expenses related primarily to intellectual property maintenance. During the year ended December 31, 2022, expenses related primarily to the wind-down activities of the Phase 3 portion of our clinical trial of mavrilimumab in COVID-19 related ARDS.
Some of the information contained in this discussion and analysis or set forth elsewhere in this Annual Report, including information with respect to our plans and strategy for our business, includes forward-looking statements within the meaning of Section 27A of the Securities Act, and Section 21E of the Securities Exchange Act of 1934, as amended, or the Exchange Act, that involve risks and uncertainties.
Some of the information contained in this discussion and analysis or set forth elsewhere in this Annual Report, including information with respect to our plans and strategy for our business, includes forward-looking statements that involve risks and uncertainties.
We recognized the $10.0 million related to the mavrilimumab license during the year ended December 31, 2022. We deferred the $12.0 million related to the rilonacept license agreement as of December 31, 2022, as no materials were shipped during the year ended December 31, 2022.
We recognized the $10.0 million related to the mavrilimumab license during the year ended December 31, 2022. We deferred the $12.0 million related to the rilonacept license agreement as of December 31, 2023, and will recognize revenue as materials are shipped.
Research and development expenses were $99.3 million for the year ended December 31, 2021, compared to $112.0 million for the year ended December 31, 2020, or a decrease of $12.7 million. Direct costs for our rilonacept program were $0.9 million, $10.8 million and $25.7 million for the years ended December 31, 2022, 2021 and 2020, respectively.
Research and development expenses were $65.5 million for the year ended December 31, 2022, compared to $99.3 million for the year ended December 31, 2021, or a decrease of $33.8 million. Direct costs for our rilonacept program were $2.6 million, $0.9 million and $10.8 million for the years ended December 31, 2023, 2022 and 2021, respectively.
In 2019, we acquired all of the outstanding securities of Primatope , the company that owned or controlled the intellectual property related to KPL-404. In connection with our acquisition of Primatope, we acquired an exclusive world-wide license to KPL-404 from BIDMC .
Abiprubart is an investigational monoclonal antibody inhibitor of CD40-CD154 costimulatory interaction. In 2019, we acquired all of the outstanding securities of Primatope , the company that owned or controlled the intellectual property related to abiprubart. In connection with our acquisition of Primatope, we acquired an exclusive world-wide license to abiprubart from BIDMC .
We also evenly split with Regeneron any proceeds received by us from any licensees, sublicensees and distributors in consideration for the sale, license or other disposition of rights with respect to ARCALYST, including upfront payments, milestone payments and royalties.
We also evenly split with Regeneron any proceeds received by us from any licensees, sublicensees and distributors in consideration for the sale, license or other disposition of rights with respect to ARCALYST, including upfront payments, milestone payments and royalties. 117 Table of Contents Research and Development Expenses Research and development expenses consist primarily of costs incurred in connection with the research and development of our product candidates.
Direct costs for our vixarelimab program were $12.8 million, $10.7 million and $8.8 million for the year ended December 31, 2022, 2021 and 2020, respectively. During the year ended December 31, 2022, expenses incurred related primarily to our ongoing Phase 2b clinical trial in prurigo nodularis.
During the year ended December 31, 2021, expenses primarily related to our Phase 2/3 clinical trial in COVID-19 related ARDS. Direct costs for our vixarelimab program were $7.7 million, $12.8 million and $10.7 million for the year ended December 31, 2023, 2022 and 2021, respectively.
We believe our estimates for the valuation allowances against certain deferred tax assets recognized in our financial statements are appropriate based upon our assessment of the factors mentioned above. We released a valuation allowance of $185.5 million during the year-ended December 31, 2022.
We believe our estimates for the valuation allowances against certain deferred tax assets recognized in our financial statements are appropriate based upon our assessment of the factors mentioned above.
As a result, we have not recorded any income tax benefits from our losses incurred in Bermuda during each reporting period, and no net operating loss carryforwards are currently available to us for those losses, while our assets remain in Bermuda.
As a result, we have not recorded any income tax benefits from our losses incurred in Bermuda during each reporting period, and no net operating loss carryforwards are currently available to us for those losses. In December 2023, Bermuda passed legislation enacting a corporate income tax effective in 2025 on companies that meets certain requirements.
During the year ended December 31, 2022, expenses incurred primarily related to the first two cohorts of our Phase 2 trial in RA, which was initiated in December 2021. During the year ended December 31, 2021, expenses incurred primarily related to manufacturing of drug product supply and other start up activities for our anticipated Phase 2 trial in RA.
During the year ended December 31, 2022, expenses incurred primarily related to the first two cohorts of our Phase 2 clinical trial of abiprubart in RA, which was initiated in December 2021.
“Risk Factors” in this Annual Report. Selling, General and Administrative Expenses Selling, general and administrative expenses consist primarily of salaries and benefits, travel and share based compensation expense for personnel in selling, marketing, medical, executive, business development, finance, human resources, legal and support personnel functions.
Selling, General and Administrative Expenses Selling, general and administrative expenses consist primarily of salaries and benefits, including share based compensation expense for personnel in selling, marketing, medical, executive, business development, finance, human resources, legal and support personnel functions. Selling, general and administrative expenses also include external commercialization, marketing, and professional fees for legal, patent, and accounting services.
During the year ended December 31, 2022, expenses primarily related to close-out activities of our RHAPSODY trial, our global, pivotal Phase 3 clinical trial in recurrent pericarditis. During the year ended December 31, 2021, expenses primarily related to the completion of RHAPSODY and the transition to the long-term extension portion of the trial.
During the year ended December 31, 2023, expenses primarily related to the purchase of supply to support life-cycle management. During the year ended December 31, 2022, expenses primarily related to close-out activities of our RHAPSODY trial, our global, pivotal Phase 3 clinical trial in recurrent pericarditis.
In addition, should there be a transfer of technology related to the manufacture of ARCALYST, then, to the extent permitted in accordance with the Regeneron Agreement, the fully-burdened costs of each of us and Regeneron incurred in performing (or having performed) such technology transfer shall also be deducted from net sales of ARCALYST to determine profit.
With respect to the technology transfer of ARCALYST drug substance manufacturing initiated by Regeneron in March 2023, to the extent permitted by the Regeneron Agreement, the fully-burdened costs of each of us and Regeneron incurred in performing such technology transfer shall also be deducted from net sales of ARCALYST to determine profit.
Our net income (losses) were $183.4 million, ($157.9) million and ($161.4) million for the years ended December 31, 2022, 2021 and 2020, respectively. We expect to incur operating losses for the foreseeable future as we advance our product candidates through preclinical and clinical development and, ultimately, seek regulatory approval.
Our net income (losses) were $14.1 million, $183.4 million and ($157.9) million for the years ended December 31, 2023, 2022 and 2021, respectively. We expect to incur significant operating losses for the foreseeable future.
Our wholly owned U.S. subsidiaries, Kiniksa US, and Primatope are subject to federal and state income taxes in the United States. Our wholly owned subsidiary Kiniksa UK, and its wholly owned subsidiaries, Kiniksa Pharmaceuticals (Germany) GmbH, Kiniksa Pharmaceuticals (France) SARL, and Kiniksa Pharmaceuticals GmbH are subject to taxation in their respective countries.
Our wholly owned subsidiary Kiniksa UK, its Swiss branch office, and Kiniksa UK’s wholly owned subsidiaries, Kiniksa Pharmaceuticals (Germany) GmbH, Kiniksa Pharmaceuticals (France) SARL, and Kiniksa Pharmaceuticals, GmbH are subject to taxation in their respective countries.
In addition, payments and royalties arising from out-licensing, collaboration or other similar agreements, though potentially substantial, are often isolated events and cannot be relied upon to generate significant and sustained revenue.
While our ARCALYST collaboration with 115 Table of Contents Regeneron has achieved profitability, there is no guarantee that our ARCALYST collaboration with Regeneron will remain profitable in the future. In addition, payments and royalties arising from out-licensing, collaboration or other similar agreements, though potentially substantial, are often isolated events and cannot be relied upon to generate significant and sustained revenue.
Under the current laws of Bermuda, there is no corporate income tax levied on an exempted company’s income, resulting in an effective zero percent tax rate.
Income Taxes Because our parent company, Kiniksa Pharmaceutical, Ltd. (“Kiniksa Bermuda”) is an exempted company incorporated under the laws of Bermuda, we are principally subject to taxation in Bermuda. Under the current laws of Bermuda, there is no corporate income tax levied on an exempted company’s income, resulting in an effective zero percent tax rate.
We expect to continue to incur collaboration expenses associated with sales of ARCALYST. Research and Development Expenses 2022/2021 2021/2020 Years Ended Comparison Comparison December 31, Increase/(Decrease) Increase/(Decrease) 2022 2021 2020 $ % $ % (in thousands) (in thousands, except percentages) Direct research and development expenses by program: Rilonacept $ 853 $ 10,842 $ 25,729 $ (9,989) (92)% $ (14,887) (58)% KPL-404 11,563 5,316 3,738 6,247 118% 1,578 42% Mavrilimumab 6,379 30,704 25,862 (24,325) (79)% 4,842 19% Vixarelimab 12,809 10,739 8,796 2,070 19% 1,943 22% Unallocated research and development expenses: Personnel related (including share-based compensation) 22,548 27,736 33,489 (5,188) (19)% (5,753) (17)% Other 11,338 13,960 14,428 (2,622) (19)% (468) (3)% Total research and development expenses $ 65,490 $ 99,297 $ 112,042 $ (33,807) (34)% $ (12,745) (11)% Research and development expenses were $65.5 million for the year ended December 31, 2022, compared to $99.3 million for the year ended December 31, 2021, or a decrease of $33.8 million.
The increase of $23.2 million in 2022 from 2021 relates primarily to an increase in revenue from the sales of ARCALYST and to a $6.0 million payment due to Regeneron related to the rilonacept Huadong Collaboration Agreement. Research and Development Expenses 2023/2022 2022/2021 Years Ended Comparison Comparison December 31, Increase/(Decrease) Increase/(Decrease) 2023 2022 2021 $ % $ % (in thousands) (in thousands, except percentages) Direct research and development expenses by program: Rilonacept $ 2,628 $ 853 $ 10,842 $ 1,775 208% $ (9,989) (92)% Abiprubart 28,388 11,563 5,316 16,825 146% 6,247 118% Mavrilimumab 768 6,379 30,704 (5,611) (88)% (24,325) (79)% Vixarelimab 7,717 12,809 10,739 (5,092) (40)% 2,070 19% Unallocated research and development expenses: Personnel related (including share-based compensation) 22,739 22,548 27,736 191 1% (5,188) (19)% Other 13,857 11,338 13,960 2,519 22% (2,622) (19)% Total research and development expenses $ 76,097 $ 65,490 $ 99,297 $ 10,607 16% $ (33,807) (34)% Research and development expenses were $76.1 million for the year ended December 31, 2023, compared to $65.5 million for the year ended December 31, 2022, or an increase of $10.6 million.
We have entered into lease agreements for office and laboratory space, and vehicles, with total future lease payments of $6.2 million, of which $3.5 million are due within one year. These agreements impact our short-term and long-term liquidity and capital needs.
We have committed to minimum payments to Regeneron of $24.9 million, all of which are due within one year. We have entered into lease agreements for office and laboratory space, and vehicles, with total future lease payments of $14.2 million, $3.0 million of which are due within one year.
As of December 31, 2022, we had cash, cash equivalents and short-term investments of $190.6 million. 133 Table of Contents Cash Flows The following table summarizes our cash flows for each of the periods presented: Years Ended December 31, 2022 2021 2020 (in thousands) Net cash provided by (used in) operating activities $ 5,807 $ (126,298) $ (136,532) Net cash provided by (used in) investing activities (8,078) 128,635 (23,444) Net cash provided by financing activities 2,516 5,885 227,086 Net increase in cash and cash equivalents and restricted cash $ 245 $ 8,222 $ 67,110 Operating Activities During the year ended December 31, 2022, operating activities provided $5.8 million of cash which primarily consisted of our net income of $183.4 million, adjusted for non-cash items of $155.0 million and working capital decreases of $22.6 million.
As of December 31, 2023, we had cash, cash equivalents and short-term investments of $206.4 million. 123 Table of Contents Cash Flows The following table summarizes our cash flows for each of the periods presented: Years Ended December 31, 2023 2022 2021 (in thousands) Net cash provided by (used in) operating activities $ 13,301 $ 5,807 $ (126,298) Net cash provided by (used in) investing activities (29,557) (8,078) 128,635 Net cash provided by financing activities 1,495 2,516 5,885 Net increase in cash and cash equivalents and restricted cash $ (14,761) $ 245 $ 8,222 Operating Activities Net cash provided by operations was $13.3 million for the year ended December 31, 2023, compared to net cash provided by operating activities of $5.8 million for the year ended December 31, 2022.
During the year ended December 31, 2020, expenses incurred primarily related to preclinical and clinical trial for our Phase 1 trial of KPL-404 in healthy volunteers, including toxicology costs. Direct costs of our mavrilimumab program were $6.4 million, $30.7 million and $25.9 million for the years ended December 31, 2022, 2021 and 2020, respectively.
During the year ended December 31, 2021, expenses incurred primarily related to manufacturing of drug product supply and other start up activities for our anticipated Phase 2 clinical trial of abiprubart in RA. Direct costs of our mavrilimumab program were $0.8 million, $6.4 million and $30.7 million for the years ended December 31, 2023, 2022 and 2021, respectively.
As a result, we expect that our research and development expenses will be substantial over the next several years as we conduct our ongoing and/or planned clinical trials for our product candidates as well as conduct other preclinical and clinical development, and make regulatory filings for our product candidates.
As a result, we expect that our research and development expenses will be substantial over the next several years as we conduct our ongoing and/or planned clinical trials for our product candidates, as well as conduct other preclinical and clinical development, and make regulatory filings for our product candidates. 118 Table of Contents At this time, we cannot reasonably estimate or know the nature, timing and costs of the efforts that will be necessary to complete the clinical development of our current or future product candidates or when, if ever, we will realize revenue from the sale of our current or future product candidates.
While we still maintain a full valuation allowance on our US deferred tax assets as of December 31, 2022, based on current US forecasted income, we may release our valuation allowance on US deferred tax assets in the future. For the year ended December 31, 2021, we recorded a provision for income taxes of $1.4 million relating primarily to U.S. current taxes from the cost-plus arrangement less amounts related to the impact of Foreign Derived Intangible Income (“FDII”) deduction and U.S. federal and state research credits.
Our UK deferred tax asset consists primarily of the tax basis of the intangible assets that were transferred to our wholly-owned UK subsidiary in 2021 and 2022. For the year ended December 31, 2021, we recorded a provision for income taxes of $1.4 million relating primarily to U.S. current taxes from the cost-plus arrangement less amounts related to the impact of FDII deduction and R&D Credits.
During the year ended December 31, 2021, expenses incurred related primarily to the initiation of our Phase 2b clinical trial in prurigo nodularis.
During the year ended December 31, 2021, expenses incurred related primarily to the initiation of our Phase 2b clinical trial of vixarelimab in prurigo nodularis. Unallocated research and development expenses were $36.6 million, $33.9 million and $41.7 million for the years ended December 31, 2023, 2022 and 2021, respectively.
Our income tax benefit relates mainly to the release of the valuation allowance on our UK deferred tax assets partially offset by provision for income taxes relating to U.S. and UK taxable income. 129 Table of Contents Results of Operations Comparison of the Years Ended December 31, 2022, 2021 and 2020 The following table summarizes our results of operations for the years ended December 31, 2022, 2021 and 2020: 2022/2021 2021/2020 Years Ended Comparison Comparison December 31, Increase/(Decrease) Increase/(Decrease) 2022 2021 2020 $ % $ % (in thousands) (in thousands, except percentages) Revenue: Product revenue, net $ 122,524 $ 38,544 $ — $ 83,980 218% $ 38,544 100% License and collaboration revenue 97,656 — — 97,656 100% — 0% Total revenue 220,180 38,544 — 181,636 471% 38,544 100% Operating expenses: Cost of goods sold 22,895 9,100 — 13,795 152% 9,100 100% Collaboration expenses 24,071 835 — 23,236 2783% 835 100% Research and development 65,490 99,297 112,042 (33,807) (34)% (12,745) (11)% Selling, general and administrative 97,951 85,948 45,321 12,003 14% 40,627 90% Total operating expenses 210,407 195,180 157,363 15,227 8% 37,817 24% Income (loss) from operations 9,773 (156,636) (157,363) 166,409 (106)% 727 0% Other income 1,253 97 1,134 1,156 1192% (1,037) (91)% Income (loss) before income taxes 11,026 (156,539) (156,229) 167,565 (107)% (310) 0% Benefit (provision) for income taxes 172,337 (1,385) (5,152) 173,722 (12,543)% 3,767 (73)% Net income (loss) $ 183,363 $ (157,924) $ (161,381) $ 341,287 (216)% $ 3,457 (2)% Product Revenue, Net We recognized net revenue from the sale of ARCALYST of $122.5 million for the year ended December 31, 2022, compared to $38.5 million for the year ended December 31, 2021, an increase of $84.0 million.
In connection with each of the foregoing transfers and /or allocations, we recognized a step-up in basis and did not incur any material tax liabilities. 119 Table of Contents Results of Operations Comparison of the Years Ended December 31, 2023, 2022 and 2021 The following table summarizes our results of operations for the years ended December 31, 2023, 2022 and 2021: 2023/2022 2022/2021 Years Ended Comparison Comparison December 31, Increase/(Decrease) Increase/(Decrease) 2023 2022 2021 $ % $ % (in thousands) (in thousands, except percentages) Revenue: Product revenue, net $ 233,176 $ 122,524 $ 38,544 $ 110,652 90% $ 83,980 218% License and collaboration revenue 37,083 97,656 — (60,573) (62)% 97,656 100% Total revenue 270,259 220,180 38,544 50,079 23% 181,636 471% Operating expenses: Cost of goods sold 33,407 22,895 9,100 10,512 46% 13,795 152% Collaboration expenses 56,524 24,071 835 32,453 135% 23,236 2783% Research and development 76,097 65,490 99,297 10,607 16% (33,807) (34)% Selling, general and administrative 129,427 97,951 85,948 31,476 32% 12,003 14% Total operating expenses 295,455 210,407 195,180 85,048 40% 15,227 8% Income (loss) from operations (25,196) 9,773 (156,636) (34,969) (358)% 166,409 (106)% Other income 8,544 1,253 97 7,291 582% 1,156 1192% Income (loss) before income taxes (16,652) 11,026 (156,539) (27,678) (251)% 167,565 (107)% Benefit (provision) for income taxes 30,736 172,337 (1,385) (141,601) (82)% 173,722 (12,543)% Net income (loss) $ 14,084 $ 183,363 $ (157,924) $ (169,279) (92)% $ 341,287 (216)% Product Revenue, Net We recognized net revenue from the sale of ARCALYST of $233.2 million, $122.5 million and $38.5 million for the years ended December 31, 2023, 2022 and 2021, respectively.
In addition, we expect to continue to incur significant expenses related to product manufacturing, including potential technology transfer costs as early as March 2023, marketing, sales and distribution of ARCALYST. We may also incur expenses in connection with the in-licensing or acquisition of additional product candidates.
We expect to continue to incur significant expenses related to product manufacturing, including technology transfer costs, sales, marketing and distribution of ARCALYST.
Following completion of this portion of the trial, the proof-of-concept portion will begin. We expect data from the trial in the first half of 2024. Mavrilimumab is an investigational monoclonal antibody inhibitor targeting GM-CSFRα. In 2017, we licensed exclusive worldwide rights in all indications to mavrilimumab from MedImmune.
We expect to announce data from Cohort 4 of the trial in the second quarter of 2024. Mavrilimumab is an investigational monoclonal antibody inhibitor targeting GM-CSFRα. In 2017, we licensed exclusive worldwide rights in all indications to mavrilimumab from MedImmune. We are currently evaluating potential partnership opportunities to advance mavrilimumab’s development.
In December 2021, we initiated a Phase 2 clinical trial of KPL-404 in RA, which is designed to evaluate pharmacokinetics, safety and efficacy with subcutaneous administration. In January 2023, we announced that we had completed enrollment of the second and final cohort of the multiple ascending dose portion of such trial.
In December 2021, we initiated a Phase 2 clinical trial of abiprubart in RA, which is designed to evaluate pharmacokinetics, safety and efficacy with subcutaneous administration. In January 2024, we announced topline clinical data from Cohorts 1, 2 and 3 of the trial, and that the trial met its primary efficacy endpoint in Cohort 3 at the weekly dose level.
Our primary exposure to market risk is interest income sensitivity, which is affected by changes in the general level of U.S. interest rates, which increased substantially over the course of 2022.
Our primary exposure to market risk is interest income sensitivity, which is affected by changes in the general level of United States interest rates. Such interest rates have and in the future may be subject to significant volatility.
For the twelve months ended December 31, 2022, we recognized net income of $183.4 million, primarily as a result of out-licensing activities and the release of our deferred tax asset valuation allowance, as compared to net losses of $157.9 million for the year ended December 31, 2021. As of December 31, 2022, we had an accumulated deficit of $492.0 million.
For the twelve months ended December 31, 2023, we recognized net income of $14.1 million, as compared to net income of $183.4 million for the year ended December 31, 2022. As of December 31, 2023, we had an accumulated deficit of $478.0 million.
The increase in the average cost per unit is largely attributable to selling through repurposed clinical supply that was previously expensed through R&D and carried at zero-cost during 2021. Collaboration Expenses Our collaboration with Regeneron continued to be profitable for the year ended December 31, 2022 after first achieving profitability in the fourth quarter of 2021.
The increase of $13.8 million in 2022 from 2021 related primarily to the increase in sales and an increase in the average cost per unit. The increase in the average cost per unit was largely attributable to selling through repurposed clinical supply that was previously expensed through R&D and carried at zero-cost during 2021.
The future viability of the Company is dependent on its ability to fund its operations through sales of ARCALYST and/or raise additional capital, such as through debt or equity offerings, as needed. We have based these estimates on assumptions that may prove to be wrong, and we could utilize our available capital resources sooner than we expect.
The future viability of our company is dependent on our ability to fund our operations through sales of ARCALYST and/or raise additional capital, such as through debt or equity offerings, as needed. We anticipate that we may require additional capital if we choose to pursue in-licenses or acquisitions of other product candidates and technologies or their related businesses.
Treasury notes and a lower average balance in short term investments. 132 Table of Contents Benefit (Provision) for Income Taxes For the year ended December 31, 2022, we recorded an income tax benefit of $172.3 million relating primarily to the release of the valuation allowance on our UK deferred tax assets.
We expect that our reported income tax expense for future periods will be higher due to the utilization of our deferred tax assets. For the year ended December 31, 2022, we recorded an income tax benefit of $172.3 million relating to a non-cash deferred tax benefit of $185.5 million primarily associated with the release of the valuation allowance on our UK deferred tax assets.
Operating Expenses Cost of Goods Sold Cost of goods sold includes production and distribution costs of ARCALYST, and amortization of the regulatory milestone, and other miscellaneous product costs associated with ARCALYST. Cost of goods sold also includes the allocations for the labor and overhead costs associated with the production of ARCALYST.
Cost of goods sold also includes labor and overhead costs associated with the production of ARCALYST associated with supply chain, quality, and regulatory activities, and the technology transfer of the manufacturing process for the ARCALYST drug substance.
The increase in product revenue was primarily driven by an increase in patients as 2022 was our first full year of sales following our commercial launch of ARCALYST in April 2021. License and Collaboration Revenue License and collaboration revenue for the year ended December 31, 2022 was $97.7 million.
The increase of $84.0 million in 2022 from 2021 was primarily driven by an increase in patients as 2022 was our first full year of sales following our commercial launch of ARCALYST in April 2021. License and Collaboration Revenue We reported $37.1 million of license and collaboration revenue for the year ended December 31, 2023, related to the Genentech License Agreement primarily driven by the achievement of $25.0 million in development milestones related to two new indications, materials delivered and our ongoing recognition of the transaction price related to the in-progress Phase 2b clinical trial of vixarelimab in prurigo nodularis.
During the year ended December 31, 2020, expenses incurred primarily related to conducting RHAPSODY, a milestone payment of $7.5 million for the achievement of a specified regulatory milestone event under the Regeneron Agreement, and supply chain costs. 131 Table of Contents Direct costs for our KPL-404 program were $11.6 million, $5.3 million and $3.7 million for the years ended December 31, 2022, 2021 and 2020, respectively.
During the year ended December 31, 2021, expenses primarily related to the completion of RHAPSODY and the transition to the long-term extension portion of the trial. Direct costs for our abiprubart program were $28.4 million, $11.6 million and $5.3 million for the years ended December 31, 2023, 2022 and 2021, respectively.
As of December 31, 2021, we maintained a full valuation allowance against our deferred tax assets of $127.9 million because we believed we would not be able to benefit from those tax deductions in the future. For the year ended December 31, 2020, we recorded a provision for income taxes of $5.2 million relating primarily to the recognition of the valuation allowance and the current year tax expense. Liquidity and Capital Resources As of December 31, 2022, our principle source of liquidity was cash, cash equivalents and short-term investments, which totaled $190.6 million.
As of December 31, 2021, we maintained a full valuation allowance against our deferred tax assets of $127.9 million. Liquidity and Capital Resources As of December 31, 2023, our principal source of liquidity was cash, cash equivalents and short-term investments, which totaled $206.4 million.
In the first quarter of 2023, following our last delivery of certain drug supplies to Genentech, Genentech became obligated to make an additional cash payment of $20.0 million.
In the fourth quarter of 2023, following the achievement of a development milestone related to a second indication under the Genentech License Agreement, Genentech became obligated to make an additional cash payment of $10.0 million, which was received in the first quarter of 2024.
Investing Activities During the year ended December 31, 2022, investing activities used $8.1 million of cash, consisting of $135.9 million of purchases of short-term investments, partially offset by $127.8 million from proceeds of maturities of short-term investments. 134 Table of Contents During the year ended December 31, 2021, investing activities provided $128.6 million of cash, consisting of $306.3 million from proceeds of maturities of short-term investments, offset by $157.3 million of purchases of short-term investments and $20.0 million related to the payment of a regulatory milestone incurred under the Regeneron Agreement.
Net cash used in investing activities was $8.1 million for the year ended December 31, 2022, compared to net cash provided by investing activities of $128.6 million for the year ended December 31, 2021 as we were able to fund our operations through operating cash flows in 2022 due to increased ARCALYST sales and cash received from out licensing activities, offset by a $20.0 million regulatory milestone incurred under the Regeneron Agreement in 2021.