INSMED Inc

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS

1. The Company and Basis of Presentation

Insmed is a people-first global biopharmaceutical company striving to deliver first- and best-in-class therapies to transform the lives of patients facing serious diseases. The Company's commercial portfolio and clinical pipeline are organized around three therapeutic areas: Respiratory, Immunology & Inflammation, and Neuro & Other Rare. To complement the Company's internal research and development, the Company also actively evaluates in-licensing and acquisition opportunities for commercial products, product candidates, and technologies.

The Company's firsttwo commercial products, ARIKAYCE®and BRINSUPRI®, are both part of the Respiratory therapeutic area. ARIKAYCE is approved in the United States (US) as ARIKAYCE (amikacin liposome inhalation suspension), in Europe as ARIKAYCE Liposomal 590 mg Nebuliser Dispersion and in Japan as ARIKAYCE inhalation 590 mg (amikacin sulfate inhalation drug product). ARIKAYCE received accelerated approval in the US in September 2018 for the treatment of Mycobacterium avium complex (MAC) lung disease as part of a combination antibacterial drug regimen for adult patients with limited or no alternative treatment options in a refractory setting. In October 2020, the European Commission (EC) approved ARIKAYCE Liposomal for the treatment of nontuberculous mycobacterial (NTM) lung infections caused by MAC in adults with limited treatment options who do not have cystic fibrosis (CF). In March 2021, Japan's Ministry of Health, Labour and Welfare (MHLW) approved ARIKAYCE for the treatment of patients with NTM lung disease caused by MAC who did not sufficiently respond to prior treatment with a multidrug regimen. NTM lung disease caused by MAC (which the Company refers to as MAC lung disease) is a rare and often chronic infection that can cause irreversible lung damage and can be fatal.

BRINSUPRI (brensocatib 25 mg and 10 mg tablets), an oral, once-daily treatment for non-cystic fibrosis bronchiectasis (referred to as bronchiectasis or NCFB) in patients 12 years of age and older, was approved in the US in August 2025. In November 2025, the EC approved BRINSUPRI (brensocatib 25 mg tablets) for the treatment of NCFB in patients 12 years of age and older with two or more exacerbations in the prior 12 months. In February 2026, the United Kingdom's (UK) Medicines and Healthcare products Regulatory Agency (MHRA) approved BRINSUPRI (brensocatib 25 mg tablets) for the treatment of NCFB in patients 12 years of age and older with two or more flare-ups or worsening of symptoms in the past 12 months. Bronchiectasis is a serious, chronic lung disease in which the bronchi become permanently dilated due to a cycle of infection, inflammation, and lung tissue damage.

The Company's Respiratory therapeutic area also includes clinical-stage programs for treprostinil palmitil inhalation powder (TPIP) and INS1148. TPIP is an inhaled dry powder formulation of the treprostinil prodrug treprostinil palmitil which may offer a differentiated product profile for pulmonary hypertension associated with interstitial lung disease (PH-ILD), pulmonary arterial hypertension (PAH), progressive pulmonary fibrosis (PPF), and idiopathic pulmonary fibrosis (IPF). INS1148 is a monoclonal antibody targeting a specific isoform of Stem Cell Factor, called Stem Cell Factor 248 (SCF248), which we plan to initially develop for PPF and IPF. The Company is also exploring additional opportunities utilizing its various technologies within the Respiratory therapeutic area.

The Company's Immunology & Inflammation therapeutic area isexploring opportunities utilizing its various technologies.

The Company's Neuro & Other Rare therapeutic area includes the clinical-stage programs INS1201, an intrathecally delivered gene therapy for patients with Duchenne muscular dystrophy (DMD), and INS1202, an intrathecally delivered gene therapy for patients with amyotrophic lateral sclerosis (ALS). The Company is also exploring additional opportunities utilizing its various technologies within the Neuro & Other Rare therapeutic area.

The Company's pre-clinical research programs encompass a wide range of technologies and modalities, including gene therapy, artificial intelligence (AI)-driven protein engineering, RNA end-joining, and synthetic rescue.

The Company was incorporated in the Commonwealth of Virginia on November 29, 1999 and its principal executive offices are located in Bridgewater, New Jersey. The Company has legal entities in the US, France, Germany, Ireland, Italy, the Netherlands, Switzerland, the UK, and Japan.

The accompanying unaudited interim consolidated financial statements have been prepared pursuant to the rules and regulations for reporting on Form 10-Q. Accordingly, certain information and disclosures required by accounting principles generally accepted in the US (GAAP) for complete consolidated financial statements are not included herein. The unaudited interim consolidated financial statements should be read in conjunction with the audited consolidated financial statements and

1. The Company and Basis of Presentation (Continued)

notes thereto included in the Company's Annual Report on Form 10-K for the year ended December 31, 2025. Any references in these notes to applicable accounting guidance are meant to refer to GAAP as found in the Accounting Standards Codification (ASC) and Accounting Standards Updates (ASU) of the Financial Accounting Standards Board (FASB).

The results of operations of any interim period are not necessarily indicative of the results of operations for the full year. The unaudited interim consolidated financial information presented herein reflects all normal and recurring adjustments that are, in the opinion of management, necessary for a fair statement of the financial position, results of operations and cash flows for the periods presented. All intercompany transactions and balances have been eliminated in consolidation. Certain prior period line items within the consolidated statements of shareholders' equity have been combined to conform to the current period presentation.

The Company had $582.2 million of cash and cash equivalents and $641.3 million of marketable securities as of March 31, 2026 and reported a net loss of $163.6 million for the three months ended March 31, 2026. The Company has funded its operations through public offerings of equity securities, debt financings, revenue interest financings, and revenues generated from ARIKAYCE and BRINSUPRI. The Company expects to continue to incur consolidated operating losses, including losses in its US and certain international entities, while funding research and development (R&D) activities for ARIKAYCE, TPIP, INS1148, INS1201, INS1202, and its other pipeline programs, and commercialization and regulatory activities for BRINSUPRI and ARIKAYCE.

The Company expects its future cash requirements to be substantial. While the Company currently has sufficient funds to meet its financial needs for at least the next 12 months, the Company may raise additional capital in the future to fund its operations, its ongoing commercialization and clinical trial activities, and its future product candidates, and to develop, acquire, in-license, or co-promote other products or product candidates, including those that address serious diseases with significant unmet need. The source, timing, and availability of any future financing or other transaction will depend principally upon continued progress in the Company’s commercial, regulatory, and development activities. Any future financing will also be contingent upon market conditions. If the Company is unable to obtain sufficient additional funds when required, the Company may be forced to delay, restrict, or eliminate all or a portion of its development programs or commercialization efforts.

The consolidated financial statements include the accounts of the Company and its wholly-owned subsidiaries, Celtrix Pharmaceuticals, Inc., Insmed France SAS, Insmed Gene Therapy LLC, Insmed Germany GmbH, Insmed Godo Kaisha, Insmed Holdings Limited, Insmed Innovation UK Limited, Insmed Ireland Limited, Insmed Italy S.R.L., Insmed Limited, Insmed Netherlands B.V., Insmed Netherlands Holdings B.V., and Insmed Switzerland GmbH.

2. Summary of Significant Accounting Policies

The Company’s complete listing of significant accounting policies is set forth in Note 2 of the notes to the consolidated financial statements in the Company's Annual Report on Form 10-K for the year ended December 31, 2025. Selected significant accounting policies are discussed in detail below.

Use of Estimates—The preparation of the consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported in the consolidated financial statements and accompanying notes. The Company bases its estimates and judgments on historical experience and on various other assumptions. The amounts of assets and liabilities reported in the Company's balance sheets and the amounts of revenues and expenses reported for each period presented are affected by estimates and assumptions, which are used for, but not limited to, the accounting for revenue allowances, stock-based compensation, income taxes, loss contingencies, acquisition related intangibles including in process research and development (IPR&D) and goodwill, fair value of contingent consideration, the revenue interest purchase agreement (the Royalty Financing Agreement), and accounting for R&D costs. Actual results could differ from those estimates.

Concentration of Credit Risk—Financial instruments that potentially subject the Company to concentrations of credit risk consist primarily of cash and cash equivalents and marketable securities. The Company places its cash equivalents and marketable securities with high credit-quality financial institutions and may invest its investments in US treasury securities, mutual funds, and government agency bonds. The Company has established guidelines relative to credit ratings and maturities that seek to maintain safety and liquidity.

The Company is exposed to risks associated with extending credit to customers related to the sale of products. The Company does not require collateral to secure amounts due from its customers. The Company uses an expected loss methodology to calculate allowances for trade receivables. The Company's measurement of expected credit losses is based on relevant information about past events, including historical experience, current conditions, and reasonable and supportable

2. Summary of Significant Accounting Policies (Continued)

forecasts that affect the collectability of the reported amount. The Company does not currently have a material allowance for uncollectible trade receivables.

The following table presents the customers representing 10% or more of the Company's gross product revenues for the three months ended March 31, 2026 and their respective percentages for the three months ended March 31, 2025.

The Company relies on third-party manufacturers and suppliers for manufacturing and supply of its products. The inability of the suppliers or manufacturers to fulfill supply requirements of the Company could materially impact future operating results. A change in the relationship with the suppliers or manufacturers, or an adverse change in their business, could materially impact future operating results.

Net Loss Per Share—Basic net loss per share is computed by dividing net loss by the weighted average number of common shares outstanding during the period. Diluted net loss per share is computed by dividing net loss by the weighted average number of common shares and other dilutive securities outstanding during the period. Potentially dilutive securities from stock options, restricted stock units (RSUs), performance stock units (PSUs) and formerly outstanding convertible debt securities would be anti-dilutive as the Company incurred a net loss. Potentially dilutive common shares resulting from the assumed exercise of outstanding stock options and from the assumed conversion of the Company's previously outstanding convertible notes are determined based on the treasury stock method.

The following table sets forth the reconciliation of the weighted average number of common shares used to compute basic and diluted net loss per share for the three months ended March 31, 2026 and 2025 (in thousands, except per share amounts):

2. Summary of Significant Accounting Policies (Continued)

The following potentially dilutive securities have been excluded from the computations of diluted weighted average common shares outstanding as of March 31, 2026 and 2025, as their effect would have been anti-dilutive (in thousands):

Recently Adopted Accounting Pronouncements—In July 2025, the FASB issued ASU 2025-05, Financial Instruments-Credit Losses (Topic 326)—Measurement of Credit Losses for Accounts Receivable and Contract Assets. The amendments provide an optional practical expedient for estimated expected credit losses on current accounts receivable and current contract assets arising from ASC 606 revenue transactions, allowing entities to assume that economic conditions at the balance sheet date will remain unchanged over the remaining life of the receivable. The amendments are effective for annual periods beginning after December 15, 2025. The Company adopted the standard effective January 1, 2026 using the prospective transition method. The adoption of ASU 2025-05 did not have a material impact on the Company's consolidated financial statements.

In September 2025, the FASB issued ASU 2025-07, Derivatives and Hedging (Topic 815) and Revenue from Contracts with Customers (Topic 606)—Derivatives Scope Refinements and Scope Clarification for Share-Based Noncash Consideration from a Customer in a Revenue Contract. The amendments clarify the scope of derivative accounting and the application of the revenue recognition guidance to share-based noncash consideration received from customers. The Company adopted the standard effective January 1, 2026, using the prospective transition method. The adoption of ASU 2025-07 did not have a material impact on the Company’s consolidated financial statements.

Recent Accounting Pronouncements (Not Yet Adopted)—In November 2024, the FASB issued ASU 2024-03, Income Statement (Subtopic 220-40)—Expense Disaggregation Disclosures, which requires disclosure of disaggregated income statement expense information about specific categories (including purchases of inventory, employee compensation, depreciation, and intangible asset amortization) in the notes to financial statements. ASU 2024-03 will be effective for fiscal years beginning after December 15, 2026 and interim periods beginning after December 15, 2027. The guidance is applied on a prospective basis, with a retrospective option, and early adoption is permitted. The Company is currently evaluating the impact of adoption of ASU 2024-03 on its consolidated financial statements.

3. Fair Value Measurements

The Company categorizes its financial assets and liabilities measured and reported at fair value in the financial statements on a recurring basis based upon the level of judgment associated with the inputs used to measure their fair value. Hierarchical levels, which are directly related to the amount of subjectivity associated with the inputs used to determine the fair value of financial assets and liabilities, are as follows:

•Level 1—Inputs are unadjusted, quoted prices in active markets for identical assets or liabilities at the measurement date.

•Level 2—Inputs (other than quoted prices included in Level 1) are either directly or indirectly observable for the assets or liability through correlation with market data at the measurement date and for the duration of the instrument’s anticipated life.

•Level 3—Inputs reflect management’s best estimate of what market participants would use in pricing the asset or liability at the measurement date. Consideration is given to the risk inherent in the valuation technique and the risk inherent in the inputs to the model.

Each major category of financial assets and liabilities measured at fair value on a recurring basis is categorized based upon the lowest level of significant input to the valuations. The fair value hierarchy also requires an entity to maximize the use of observable inputs and minimize the use of unobservable inputs when measuring fair value. Financial instruments in Level 1 generally include US treasuries and mutual funds listed in active markets. The Company's cash and cash equivalents permit daily redemption and the fair values of these investments are based upon the quoted prices in active markets provided by the holding financial institutions.

The following table shows assets and liabilities that are measured at fair value on a recurring basis and their carrying value (in millions):

During the three months ended March 31, 2026, there wereno purchases of marketable securities and$284.0 millionof marketable securities, consisting of US Treasury Bills, matured.

As of March 31, 2026, the Company held $641.3 million of available-for-sale securities. Marketable securities maturing in one year or less are classified as current assets and marketable securities maturing in more than one year are classified as non-current assets.

The Company recognizes transfers between levels within the fair value hierarchy, if any, at the end of each quarter. There were no transfers in or out of Level 1, Level 2, or Level 3 during the three months ended March 31, 2026. During the three months ended March 31, 2026, no new Level 1 assets were added.

The Company reviews the status of each security quarterly to determine whether an other-than-temporary impairment has occurred. In making its determination, the Company considers a number of factors, including: (1) the significance of the decline; (2) whether the security was rated below investment grade; (3) failure of the issuer to make scheduled interest or principal payments; and (4) the Company's ability and intent to retain the investment for a sufficient period of time for it to recover. The Company has determined that there were no other-than-temporary impairments during the three months ended March 31, 2026.

Contingent Consideration

The contingent consideration liabilities arose from the acquisition of Motus Biosciences, Inc. and AlgaeneX, Inc. in August 2021 (together, the Business Acquisition). The contingent consideration liabilities consist of developmental and regulatory milestones, a priority review voucher (PRV) milestone, and net sales milestones. As of March 31, 2026, the Company was obligated to issue to Motus equityholders up to 4,610,838 shares of the Company's common stock in the aggr egate and AlgaeneX equityholders up to 368,867 shares of the Company's common stock in the aggregate upon the achievement of certain development and regulatory milestone events. Thefair value of the development and regulatory milestones are estimated utilizing a probability-adjusted approach. The weighted average probability of success of the remaining development and regulatory milestones was 31% as of March 31, 2026. The development and regulatory milestones, if achieved, will be settled in shares of the Company's common stock. As such, there is no discount rate applied in the fair value calculation. During the third quarter of 2025 and first quarter of 2026, development milestones in connection with the Motus acquisition were achieved, resulting in the issuance of 364,566 shares of the Company's common stock in October 2025 and 364,397 shares of the Company's common stock in March 2026, respectively.

If the Company were to receive a PRV, the Company would be obligated to pay to the Motus equityholders a portion of the value of the PRV, subject to certain reductions. The potential payout will be either 50% of the after tax net proceeds received by the Company from a sale of the PRV or 50% of the average of the sales prices for the last three publicly disclosed PRV sales, less certain adjustments. The fair value of the PRV milestone is estimated utilizing a probability-adjusted discounted cash flow approach. This obligation will be settled in cash. On December 20, 2024, the FDA's PRV program expired. As of December 31, 2025, the Company determined that the likelihood of receiving a PRV was remote and the related milestone had no fair value. On February 3, 2026, the PRV program was reauthorized. As of March 31, 2026, the Company determined that the value of the PRV milestone was$15.2 million.

The contingent consideration liabilities for net sales milestones were valued using an option pricing model with Monte Carlo simulation. As of March 31, 2026, the fair value of these net sales milestones were deemed immaterial to the overall fair value of the contingent consideration.

The contingent consideration liabilities have been classified as a Level 3 recurring liability as its valuation requires substantial judgment and estimation of factors that are not currently observable in the market. If different assumptions were used for the inputs to the valuation approach, the estimated fair value could be significantly different than the fair value the Company determined. Contingent consideration liabilities expected to be settled within twelve months are classified as a current liability within accounts payable and accrued liabilities. Contingent consideration liabilities expected to be settled in more than twelve months are classified as a non-current liability. As of March 31, 2026, there wasno current contingent consideration outstanding, and the fair value of the non-current contingent consideration was $270.3 million.

A valuation of the contingent consideration liabilities is performed quarterly with gains and losses included within change in fair value of contingent consideration in the consolidated statements of comprehensive loss. The following significant unobservable inputs were used in the valuation of the contingent consideration liabilities as of March 31, 2026 and December 31, 2025:

A rollforward of the Company's valuations for the contingent consideration liabilities for the three months ended March 31, 2026 and 2025 follows (in thousands):

The change in fair value of contingent consideration liabilities is due to changes in factors such as the probability of achieving milestones, the Company's stock price, or certain other estimated assumptions. Payments were made in shares of the Company's common stock.

Royalty Financing Agreement

The fair value of the Royalty Financing Agreement at the time of the transaction was based on the Company’s estimates of future royalties expected to be paid to OrbiMed Royalty & Credit Opportunities IV, LP (OrbiMed) over the life of the arrangement, which was determined using forecasts from market data sources, which are considered Level 3 inputs. This liability is being amortized using the effective interest method over the life of the arrangement, in accordance with ASC 470, Debt and ASC 835, Interest. The Company will utilize the prospective method to account for subsequent changes in the estimated future payments to be made to OrbiMed and will update the effective interest rate on a quarterly basis. The carrying value of the Royalty Financing Agreement approximates fair value. See Note 11 - Royalty Financing Agreementfor further details.

Secured Senior Term Loan

The carrying value of the Company's secured senior term loans are measured at amortized cost using the effective interest method and the carrying value approximates fair value. See Note 10 - Debt for further details.

4. Product Revenues, Net

In accordance with ASC 606, Revenue from Contracts with Customers, the Company recognizes revenue when a customer obtains control of promised goods or services, in an amount that reflects the consideration the Company expects to receive in exchange for the goods or services provided. To determine revenue recognition for arrangements within the scope of ASC 606, the Company performs the following five steps: (1) identify the contracts with a customer; (2) identify the performance obligations in the contract; (3) determine the transaction price; (4) allocate the transaction price to the performance obligations in the contract; and (5) recognize revenue when or as the entity satisfies a performance obligation. At contract inception, the Company assesses the goods or services promised within each contract to determine which are performance obligations and to assess 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 all contracts that fall into the scope of ASC 606, the Company has identified one performance obligation: the sale of its marketed products to its customers. The Company has not incurred or capitalized any incremental costs associated with obtaining contracts with customers.

Product revenues, net consist of global net sales of ARIKAYCE and net sales of BRINSUPRI. The Company's customers in the US include specialty pharmacies and a specialty distributor. Product revenues are recognized once the Company performs and satisfies all five steps of the revenue recognition criteria described above.

4. Product Revenues, Net (Continued)

The following tables present a geographic summary of the Company's product revenues, net, for the three months ended March 31, 2026 and 2025 (in thousands):

The Company also recognizes revenue related to various managed access programs. The Company began recognizing international BRINSUPRI revenue related to early access programs (EAPs) in Europe, consisting of sales to the French National Agency for Medicines and Health Products Safety, which has granted BRINSUPRI a Compassionate Access Authorisation (Autorisation d'accès compassionnel or AAC) and sales through the named patient program (NPP) in other countries.

Revenue is recorded at net selling price (transaction price), which includes estimates of variable consideration for which reserves are established for (a) customer credits, such as invoice discounts for prompt pay, (b) estimated government rebates, such as Medicaid and Medicare Part D reimbursements, and estimated managed care rebates, (c) estimated chargebacks, and (d) estimated costs of co-payment assistance. These reserves are based on the amounts earned or to be claimed on the related sales and are classified as reductions of accounts receivable (prompt pay discounts and chargebacks), prepaid expenses (co-payment assistance), or as a current liability (rebates). Where appropriate, these estimates take into consideration a range of possible outcomes which are probability-weighted for relevant factors such as the Company's historical experience, current contractual and statutory requirements, 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 applicable contract. The amount of variable consideration 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 will not occur in a future period. Actual amounts of consideration ultimately received may differ from the Company's estimates. If actual results in the future vary from estimates, the Company adjusts these estimates, which would affect net product revenue and earnings in the period such variances become known.

Customer credits: Certain of the Company's customers are offered various forms of consideration, including prompt payment discounts. The payment terms for sales to specialty pharmacies and specialty distributors for prompt payment discounts are based on contractual rates agreed with the respective specialty pharmacies and distributors. The Company anticipates that its customers will earn these discounts and, therefore, deducts the full amount of these discounts from total gross product revenues at the time such revenues are recognized.

Rebates: The Company contracts with certain government agencies and managed care organizations, or collectively, third-party payors, so that its marketed products will be eligible for purchase by, or partial or full reimbursement from, such third-party payors. The Company estimates the rebates it will provide to third-party payors and deducts these estimated amounts from total gross product revenues at the time the revenues are recognized. These reserves are recorded in the same period in which the revenue is recognized, resulting in a reduction of product revenue and the establishment of a current liability. The current liability is included in accounts payable and accrued liabilities on the consolidated balance sheets. The Company estimates the rebates that it will provide to third-party payors based upon (i) the Company's contracts with these third-party payors, (ii) the government mandated discounts applicable to government-funded programs, (iii) a range of possible outcomes

4. Product Revenues, Net (Continued)

that are probability-weighted for the estimated payor mix, and (iv) information obtained from the Company's specialty pharmacies.

Chargebacks: Chargebacks are discounts that occur when certain contracted customers, currently public health service institutions and federal government entities purchasing via the Federal Supply Schedule, purchase directly from the Company's specialty distributor. Contracted customers generally purchase the product at a discounted price and the specialty distributor, in turn, charges back to the Company the difference between the price the specialty distributor initially paid and the discounted price paid by the contracted customers. The Company estimates chargebacks provided to the specialty distributor and deducts these estimated amounts from gross product revenues, and from accounts receivable, at the time revenues are recognized.

Co-payment assistance: Patients who have commercial insurance and meet certain eligibility requirements may receive co-payment assistance. Based upon the terms of the program and information regarding programs provided for similar specialty pharmaceutical products, the Company estimates the average co-pay mitigation amounts and the percentage of patients that it expects to participate in the program in order to establish accruals for co-payment assistance. These reserves are recorded in the same period in which the related revenue is recognized, resulting in a reduction of product revenue. The Company adjusts its accruals for co-pay assistance based on actual redemption activity and estimates of future redemptions related to sales in the current period.

If any, or all, of the Company's actual experience varies from its estimates, the Company may need to adjust prior period accruals, affecting revenue in the period of adjustment.

5. Inventory

The Company's inventory balance consists of the following (in thousands):

Inventory is stated at the lower of cost and net realizable value and consists of raw materials, work-in-process and finished goods. The Company has not recorded any significant inventory write-downs. The Company currently uses a limited number of third-party contract manufacturing organizations (CMOs) to produce its inventory.

6. Intangibles, Net and Goodwill

Intangibles, Net

Finite-lived Intangible Assets

As of March 31, 2026, the Company's finite-lived intangible assets consisted of acquired ARIKAYCE R&D, the milestones paid to PARI Pharma GmbH (PARI) for the license to use the Lamira® Nebulizer System (Lamira) for the delivery of ARIKAYCE to patients as a result of the FDA and EC approvals of ARIKAYCE in September 2018 and October 2020, respectively, the milestone paid to AstraZeneca AB (AstraZeneca) as a result of the FDA approval of BRINSUPRI in August 2025, and the milestone paid to AstraZeneca as a result of the EC approval of BRINSUPRI in November 2025. The Company began amortizing its acquired ARIKAYCE R&D and PARI milestone-related intangible assets in October 2018, over ARIKAYCE's initial regulatory exclusivity period of 12 years, and began amortizing its AstraZeneca milestone-related intangible assets in August and November 2025 over BRINSUPRI's regulatory exclusivity period of approximately 14 years. Amortization expense is estimated to be $8.3 million per year for the years 2026 through 2029 and $7.1 million for 2030.

Indefinite-lived Intangible Assets

As of March 31, 2026, the Company's indefinite-lived intangible assets consisted of acquired IPR&D from the Business Acquisition. Indefinite-lived intangible assets are not amortized.

6. Intangibles, Net and Goodwill (Continued)

A rollforward of the Company's intangible assets for the three months ended March 31, 2026 and 2025 is as follows (in thousands):

Goodwill

The Company's goodwill balance of $136.1 million as of March 31, 2026 and December 31, 2025, resulted from the August 2021 Business Acquisition.

7. Fixed Assets, Net

Fixed assets are stated at cost and depreciated using the straight-line method, based on useful lives as follows (in thousands):

8. Accounts Payable and Accrued Liabilities

Accounts payable and accrued liabilities consist of the following (in thousands):

9. Leases

The Company's lease portfolio consists primarily of office and laboratory space, manufacturing facilities, research equipment and fleet vehicles. All of the Company's leases are classified as operating leases, except for the Company's leases of its corporate headquarters and a research facility in San Diego, which are classified as finance leases. The terms of the Company's lease agreements that have commenced range from less thanone year toten years, ten months. In its assessment of the term of each such lease, the Company has not included any options to extend or terminate the lease due to the absence of economic incentives in its lease agreements. Leases that qualify for treatment as a short-term lease are expensed as incurred. These short-term leases are not material to the Company's financial position. Furthermore, the Company does not separate lease and non-lease components for all classes of underlying assets. The Company's leases do not contain residual value guarantees and it does not sublease any of its leased assets.

The Company outsources its manufacturing operations to CMOs. Upon review of the agreements with its CMOs, the Company determined that these contracts contain embedded leases for dedicated manufacturing facilities. The Company obtains substantially all of the economic benefits from the use of the manufacturing facilities, the Company has the right to direct how and for what purpose the facility is used throughout the period of use, and the supplier does not have the right to change the operating instructions of the facility. The operating lease right-of-use assets and corresponding lease liabilities associated with the manufacturing facilities is the sum of the minimum guarantees over the life of the production contracts.

The Company records variable consideration for variable lease payments in excess of fixed fees or minimum guarantees. Variable consideration related to the Company's leasing arrangements was $7.6 million and $2.5 million for the three months ended March 31, 2026 and 2025, respectively. Variable costs related to CMO manufacturing agreements are direct costs related to the manufacturing of ARIKAYCE and are capitalized within inventory in the Company's consolidated balance sheet, while the variable costs related to other leasing arrangements, not related to the manufacturing of ARIKAYCE, have been classified within operating expenses in the Company's consolidated statements of comprehensive loss.

During the three months ended March 31, 2026 and 2025, the Company did not acquire any new right-of-use assets in exchange for lease obligations.

9. Leases (Continued)

In addition to the Company's lease agreements that have previously commenced and are reflected in the consolidated financial statements, the Company has entered into additional lease agreements that have not yet commenced. The Company entered into certain agreements with Patheon UK Limited (Patheon) related to increasing its long-term production capacity for ARIKAYCE commercial inventory. The Company has determined that these agreements with Patheon contain an embedded lease for the manufacturing facility and the specialized equipment contained therein. As of March 31, 2026 and December 31, 2025, costs of$72.5 million and $69.5 million, respectively, incurred by the Company under these additional agreements have been classified within other assets in the Company'sconsolidated balance sheet. Upon the commencement date, prepaid costs and minimum guarantees specified in the agreement will be combined to establish an operating lease ROU asset and operating lease liability.

10. Debt

Amended and Restated Loan Agreement

In October 2022, the Company entered into the$350.0 million loan agreement (the Loan Agreement) with Pharmakon Advisors LP (Pharmakon) that would have matured on October 19, 2027 (the Tranche A Term Loan). The Tranche A Term Loan originally bore interest at a rate based upon the Secured Overnight Financing Rate (SOFR), subject to a SOFR floor of 2.5%, in addition to a margin of 7.75% per annum. Up to 50% of the interest payable during the first 24 months from the closing of the Tranche A Term Loan could have been paid-in-kind at the Company's election. If elected, paid-in-kind interest would have been capitalized and added to the principal amount of the Tranche A Term Loan. The Tranche A Term Loan, including the paid-in-kind interest, would have been repaid ineight equal quarterly payments starting in the 13th quarter following the closing of the Tranche A Term Loan (i.e., the quarter ending March 31, 2026), except that the repayment start date could have been extended at the Company's option for an additional four quarters, so that repayments start in the 17th quarter following the closing of the Tranche A Term Loan, subject to the achievement of specified ARIKAYCE data thresholds and certain other conditions. Net proceeds from the Tranche A Term Loan, after deducting the lenders fees and deal expenses of $15.1 million, were $334.9 million.

In October 2024, the Company entered into an Amended and Restated Loan Agreement, as amended on July 10, 2025, (the A&R Loan Agreement) with BioPharma Credit PLC, BPCR Limited Partnership and BioPharma Credit Investments V (Master) LP, which are funds managed by Pharmakon, and the guarantors party to such agreement. The A&R Loan Agreement amended and restated the Loan Agreement, dated as of October 19, 2022, pursuant to which the Tranche A Term Loan was provided. The A&R Loan Agreement, among other items, provides an additional $150.0 million senior secured term loan tranche (the Tranche B Term Loan and, together with the Tranche A Term Loan, the Term Loans). The A&R Loan Agreement extends the maturity of the Term Loans to September 30, 2029, subject to acceleration to February 1, 2028 on the occurrence of certain prespecified events, and amends the interest rate on the Term Loans to a fixed rate of 9.6% per annum. As consideration for the provision of the Tranche B Term Loan, the Company agreed to pay Pharmakon a fee equal to 2.0% of the Tranche B Term Loan at the closing date of the Tranche B Term Loan and an additional exit fee of 2.0% of the amount of each prepayment or repayment of the Term Loans. The Term Loans will be repaid ineight equal quarterly payments starting on January 3, 2028. Net proceeds from the Tranche B Term Loan, after deducting the lenders fees and administrative expenses of $3.7 million, were $146.3 million.

The following table presents the carrying value of the Company’s Term Loans balance as of March 31, 2026 and December 31, 2025 (in thousands):

10. Debt (Continued)

As of March 31, 2026, future principal repayments of debt for each of the fiscal years through maturity were as follows (in thousands):

Interest Expense

Interest expense for the three months ended March 31, 2026 and 2025 was as follows (in thousands):

11. Royalty Financing Agreement

In October 2022, the Company entered into the Royalty Financing Agreement with OrbiMed. Under the Royalty Financing Agreement, OrbiMed paid the Company $150.0 million in exchange for the right to receive, on a quarterly basis, royalties in an amount equal to 4.0% of ARIKAYCE global net sales prior to September 1, 2025 and 4.5% of ARIKAYCE global net sales on or after September 1, 2025, as well as 0.75% of brensocatib global net sales, which includes BRINSUPRI. In the event that OrbiMed has not received aggregate Revenue Interest Payments of at least $150.0 million on or prior to March 31, 2028, the Company must make a one-time payment to OrbiMed for the difference between the $150.0 million and the aggregated Revenue Interest Payments that have been paid. In addition, the royalty rate for ARIKAYCE will be increased beginning March 31, 2028 to the rate which would have resulted in aggregate Revenue Interest Payments as of March 31, 2028 equaling $150.0 million. The total Revenue Interest Payments payable by the Company to OrbiMed are capped at 1.8 x of the purchase price or up to a maximum of 1.9 x of the purchase price under certain conditions. Net proceeds from the Royalty Financing Agreement, after deducting the lenders fees and deal expenses of $3.8 million, were $146.2 million. The Royalty Financing Agreement was amended in October 2024 to, among other things, amend certain restrictions on the Company’s ability to incur indebtedness.

The fair value of the Royalty Financing Agreement at the time of the transaction was based on the Company’s estimates of future royalties expected to be paid to OrbiMed over the life of the arrangement, which was determined using forecasts from market data sources, which are considered Level 3 inputs. This liability is being amortized using the effective interest method over the life of the arrangement, in accordance with ASC 470, Debt and ASC 835, Interest. The initial annual effective interest rate was determined to be 12.4%. The Company is utilizing the prospective method to account for subsequent changes in the estimated future payments to be made to OrbiMed and updates the effective interest rate on a quarterly basis.

11. Royalty Financing Agreement (Continued)

The following table presents the activity of the Company's Royalty Financing Agreement balance for the three-month period ended March 31, 2026 and year ended December 31, 2025 (in thousands):

The Revenue Interest Payments payable in connection with the Royalty Financing Agreement were $6.0 million and $6.4 million as of March 31, 2026 and December 31, 2025, respectively, which were recorded within accounts payable and accrued expenses on the consolidated balance sheet. Non-cash interest expense is recorded within interest expense in the consolidated statements of comprehensive loss.

12. Shareholders' Equity

Common Stock—As of March 31, 2026, the Company had 500,000,000 shares of common stock authorized with a par value of $0.01 per share and 216,521,841 shares of common stock issued and outstanding. In addition, as of March 31, 2026, the Company had reserved 16,530,357 shares of common stock for issuance upon the exercise of outstanding stock options, and 4,067,262 shares of common stock for issuance upon the vesting of RSUs and 267,435 shares for issuance upon the vesting of PSUs. In connection with the Business Acquisition, the Company reserved 9,406,112 shares of the Company’s common stock, subject to certain closing-related reductions.

Of the 9,406,112 shares reserved, subject to certain closing-related reductions, the Company issued 2,889,367 shares of the Company's common stock in connection with the Business Acquisition in the third quarter of 2021, after certain closing-related deductions.171,427,177,203, and 182,182 shares of the Company’s common stock reserved in connection with the Motus acquisition were issued as acquisition consideration on the first, second and third anniversaries of the closing date of the acquisition, respectively, in each case subject to certain reductions. During the third quarter of 2025 and first quarter of 2026, development milestones in connection with the Motus acquisition were achieved, resulting in the issuance of 364,566 shares of the Company's common stock in October 2025 and 364,397 shares of the Company's common stock in March 2026, respectively. Additional shares of the Company's common stock will also be issued upon the achievement of certain development and regulatory milestone events, subject to certain reductions. As of March 31, 2026,4,979,705 sharesof the Company's common stock remain reserved for the Business Acquisition.

Preferred Stock—As of March 31, 2026, the Company had 200,000,000 shares of preferred stock authorized with a par value of $0.01 per share andno shares of preferred stock were issued and outstanding.

13. Stock-Based Compensation

The Company's current equity compensation plan, the Insmed Incorporated Amended and Restated 2019 Incentive Plan (the 2019 Incentive Plan), was approved by shareholders at the Company's Annual Meeting of Shareholders on May 13, 2023. The 2019 Incentive Plan replaced the Insmed Incorporated 2019 Incentive Plan, as amended, and provided for awards of up to an aggregate of 24,250,000 shares (including the shares previously available for grant under the Insmed Incorporated 2019 Incentive Plan). At the Company's 2024 Annual Meeting of Shareholders, the Company's shareholders approved Amendment No. 1 to the 2019 Incentive Plan, which provides for the issuance of an additional 3,000,000 shares under the 2019 Incentive Plan. At the Company's 2025 Annual Meeting of Shareholders, the Company's shareholders approved Amendment No. 2 to the 2019 Incentive Plan, which provides for the issuance of an additional 10,000,000 shares under the 2019 Incentive Plan. As of March 31, 2026,10,126,431 shares remain available for future issuance under the 2019 Incentive Plan. The 2019 Incentive Plan will terminate on April 3, 2029, unless it is extended or terminated earlier pursuant to its terms.

13. Stock-Based Compensation (Continued)

In addition, from time to time, the Company makes inducement grants of stock options and RSUs to new hires, which awards are made pursuant to the Nasdaq's inducement grant exception to the shareholder approval requirement for grants of equity compensation. The Company granted inducement stock options and RSUs covering 73,657 shares of the Company's common stock to new employees during the three months ended March 31, 2026. In February 2025, the Company adopted the Insmed Incorporated 2025 Inducement Plan, under which the Company is authorized to grant a variety of inducement awards, including stock options and RSUs, up to an aggregate of 1,000,000 shares, as an inducement to become an employee of the Company or any of its subsidiaries. As of March 31, 2026,626,576 shares remain available for future issuance under the Insmed Incorporated 2025 Inducement Plan.

On May 15, 2018, the 2018 Employee Stock Purchase Plan (ESPP) was approved by shareholders at the Company's 2018 Annual Meeting of Shareholders. The ESPP allows eligible employees to acquire an ownership interest in the Company by purchasing common stock, at a discount, through payroll deductions. The Company has reserved the following for issuance under the ESPP: (i)1,000,000 shares of common stock, plus (ii) commencing on January 1, 2019 and ending on December 31, 2023, an additional number of shares added on the first day of each calendar year equal to the lesser of (A)1,200,000 shares of common stock, (B)2% of the number of outstanding shares of common stock on such date and (C) an amount determined by the administrator.

Stock Options—As of March 31, 2026, there was $163.4 million of unrecognized compensation expense related to unvested stock options. As of March 31, 2026, the Company had performance-conditioned options totaling 114,780 shares outstanding which had not yet met the recognition criteria.

Restricted Stock Units—As of March 31, 2026, there was $260.1 million of unrecognized compensation expense related to unvested RSU awards.

Performance Stock Units—As of March 31, 2026, there were 92,219 PSUs outstanding with an unrecognized compensation expense of$18.1 million, which assumes a 100% payout for these awards.

The following table summarizes the aggregate stock-based compensation expense recorded in the consolidated statements of comprehensive loss related to stock options, RSUs, PSUs and the ESPP during the three months ended March 31, 2026 and 2025 (in thousands):

14. Income Taxes

The Company recorded a provision for income taxes of $1.5 million and $0.9 million for the three months ended March 31, 2026 and 2025, respectively. The provisions recorded for the three months ended March 31, 2026 and 2025 are primarily a result of the Company's international subsidiaries that had taxable income during the periods and income tax on modified gross revenues imposed by certain US states. There was a full valuation allowance recorded against the Company's deferred tax assets and thereforeno tax benefit was recorded.

The Company is subject to US federal, state and international income taxes and the statute of limitations for tax audit is open for the Company’s federal tax returns for the years ended 2022 and later, generally open for certain states for the years 2021 and later, and generally open for international jurisdictions for the years 2020 and later. The Company has incurred net operating losses since inception, except for the year ended December 31, 2009. Such loss carryforwards would be subject to audit in any tax year in which those losses are utilized, notwithstanding the year of origin. As of March 31, 2026 and December 31, 2025, the Company had recorded reserves for unrecognized income tax benefits against certain deferred tax assets in the US. However, given the Company’s valuation allowance position, these reserves do not have an impact on the balance sheet as of March 31, 2026 and December 31, 2025 or the consolidated statements of comprehensive loss for the three months ended March 31, 2026 and 2025. The Company hasnot recorded any accrued interest or penalties related to uncertain tax positions.

15. Commitments and Contingencies

Commitments

The Company has entered into various commitments including, but not limited to, asset acquisition and license agreements. See Note 16 - Commitments and Contingencies in the Company’s Annual Report on Form 10-K for the fiscal year ended December 31, 2025 for further information.

Rent expense charged to operations was $3.5 million for each of the three months ended March 31, 2026 and 2025.

Legal Proceedings

From time to time, the Company is a party to various lawsuits, claims and other legal proceedings that arise in the ordinary course of business. While the outcomes of these matters are uncertain, management does not expect that the ultimate costs to resolve these matters will have a material adverse effect on the Company's consolidated financial position, results of operations or cash flows.

16. Segment Reporting

The Company manages its business activities on a consolidated basis and operates as a single operating segment. The Company derives its revenues from the development and commercialization of therapies for patients facing serious diseases. The accounting policies of the segment are the same as those described in Note 2–Summary of Significant Accounting Policies.

The Company has a single management team that reports to the Chief Executive Officer, the chief operating decision maker (CODM), who comprehensively manages the entire business. When evaluating the Company’s financial performance, the CODM regularly reviews total revenues, total expenses, and expenses by function, and makes decisions using this information on a global basis. The CODM uses net loss, as reported in the consolidated statements of comprehensive loss, in evaluating the performance of the segment. Decisions regarding resource allocation are made primarily during the annual budget planning process and augmented as needed throughout the year. The measure of segment assets is reported on the balance sheet as total assets. The Company does not operate separate lines of business with respect to its products or product candidates. Accordingly, the Company hasone reportable segment.

16. Segment Reporting (Continued)

Segment loss, including significant segment expenses, for the three months ended March 31, 2026 and 2025 was as follows (in thousands):

(a) Other segment items include stock-based compensation, professional fees, and facility-related expenses.