Insmed Features the Global Phase 3 PALM Clinical Development Program Evaluating Treprostinil Palmitil Inhalation Powder (TPIP) at CHEST 2026

—Insmed's Largest Parallel-Running Clinical Effort to Date With Four Pivotal Phase 3 Studies Advancing Across Four Progressive Pulmonary Diseases: PALM-PAH, PALM-ILD, PALM-PPF, and PALM-IPF—

—One of the Broadest Active Global Clinical Programs in the Pulmonary Space, With the Potential to Redefine Prostanoid Therapy for These Patient Populations—

BRIDGEWATER, N.J., Oct. 15, 2026 /PRNewswire/ -- Insmed Incorporated (Nasdaq: INSM), a people-first global biopharmaceutical company striving to deliver first- and best-in-class therapies to transform the lives of patients facing serious diseases, will feature the global PALM Clinical Development Program at the American College of Chest Physicians ® Annual Meeting 2026 (CHEST 2026), which is investigating treprostinil palmitil inhalation powder (TPIP) in a range of serious pulmonary diseases. The PALM Clinical Development Program includes four pivotal, parallel-running Phase 3 studies evaluating TPIP as a once-daily therapy for patients with pulmonary arterial hypertension (PAH), pulmonary hypertension associated with interstitial lung disease (PH-ILD), progressive pulmonary fibrosis (PPF), and idiopathic pulmonary fibrosis (IPF). Three PALM Phase 3 studies (PALM-PAH, PALM-ILD, PALM-PPF) have now been initiated, with the fourth study (PALM-IPF) expected to begin in the first half of 2027. This program aims to enroll more than 2,000 patients across these four studies.

"People living with debilitating pulmonary diseases often face substantial burdens as their disease progresses, compounded by complex treatment regimens and systemic side effects that can make the demands of everyday life increasingly difficult," said Raymond Benza, MD, Chair of Cardiology, Sentara Health and Section Chief of Cardiology at the Macon & Joan Brock Virginia Health Sciences, Eastern Virginia Medical School at Old Dominion University. "As clinicians, we see firsthand the need to address the progressive nature of these diseases while considering the demands of long-term therapy. The PALM Clinical Development Program has the potential to demonstrate the impact of a novel, once-daily inhaled prostanoid therapy for patients across four serious pulmonary diseases."

Building on clinically meaningful Phase 2 efficacy and safety data evaluating TPIP in PAH and PH-ILD, the PALM Clinical Development Program is driven by the urgency to address treatment challenges and advance the standard of care for patients living with these serious diseases. The program is designed to establish investigational TPIP as a highly differentiated, purposefully designed, once-daily therapy with the potential to deliver meaningful outcomes across a broad range of patients. Background on each of the studies is as follows:

• PALM-PAH is a Phase 3, randomized, double-blind, placebo-controlled, multicenter, parallel-group study evaluating the efficacy and safety of once-daily TPIP in patients with PAH (World Health Organization [WHO] Group 1 pulmonary hypertension) over 24 weeks. The primary endpoint is change from baseline in 6-minute walk distance (6MWD) at Week 24. Secondary endpoints assess functional status, disease severity, patient-reported outcomes, time to first clinical worsening, and pharmacokinetics (ClinicalTrials.gov ID: NCT07481981).

• PALM-ILD is a Phase 3, randomized, double-blind, placebo-controlled, multicenter, parallel-group study evaluating the efficacy and safety of once-daily TPIP in patients with PH-ILD (WHO Group 3 pulmonary hypertension) over 24 weeks. The primary endpoint is change from baseline in 6MWD at Week 24, with time to first major morbidity or mortality event over the 24-week treatment period as a secondary endpoint (ClinicalTrials.gov ID: NCT07179380).

• PALM-PPF is a Phase 3, randomized, double-blind, placebo-controlled, multicenter, parallel-group study evaluating the safety and efficacy of once-daily TPIP in adult patients with PPF over 52 to 104 weeks. The study's primary endpoint is change from baseline in absolute forced vital capacity (FVC) at Week 52, with secondary endpoints assessing disease progression, functional and physiological decline, patient-reported impact, pharmacokinetics, and safety (ClinicalTrials.gov ID: NCT07805785).

• PALM-IPF will be a Phase 3, randomized, double-blind, placebo-controlled, multicenter, parallel-group study evaluating the safety and efficacy of once-daily TPIP in adult patients with IPF over 52 to 104 weeks. The study's primary endpoint will be change from baseline in absolute FVC at Week 52, with secondary endpoints assessing disease progression, functional and physiological decline, and patient-reported impact, pharmacokinetics, and safety (ClinicalTrials.gov listing forthcoming).

"As TPIP continues into the next stage of clinical development, this multi-indication PALM Clinical Development Program — the most ambitious clinical effort we are undertaking to date — is designed to break through treatment barriers that have historically limited innovation of prostanoid treatment for these complex pulmonary disorders," said Martina Flammer, M.D., MBA, Chief Medical Officer of Insmed. "These four Phase 3 studies further evaluate TPIP's potential to meaningfully improve care and, if successful, emerge as the prostanoid of choice for clinicians and patients."

Treprostinil palmitil inhalation powder (TPIP) is an investigational dry powder formulation of treprostinil palmitil, a next-generation pro-drug formulation of inhaled treprostinil consisting of treprostinil linked by an ester bond to a 16-carbon chain. Designed entirely in Insmed's laboratories, TPIP is a potentially highly differentiated prostanoid being developed as a once-daily therapy for the treatment of patients with pulmonary arterial hypertension (PAH), pulmonary hypertension associated with interstitial lung disease (PH-ILD), progressive pulmonary fibrosis (PPF), and idiopathic pulmonary fibrosis (IPF). TPIP is administered in a capsule-based inhalation device. TPIP is an investigational drug product that has not been approved for any indication in any jurisdiction.

Pulmonary arterial hypertension (PAH), classified as WHO Group 1 Pulmonary Hypertension, is a serious, progressive, rare disease in which the blood vessels in the lungs narrow or become obstructed, leading to high blood pressure in the pulmonary arteries. The most common symptoms include shortness of breath, chest pain, dizziness or fainting, fatigue, and weakness. Untreated PAH can be debilitating and often fatal.

Pulmonary hypertension associated with interstitial lung disease (PH-ILD), also known as WHO Group 3 Pulmonary Hypertension, is a common and serious complication of several interstitial lung diseases (ILDs), a group of more than 200 chronic lung disorders marked by inflammation and fibrosis of the lung tissue. PH-ILD is strongly associated with impaired quality of life, decreased functional capacity, greater supplemental oxygen requirements, increased risk of hospitalizations, and higher mortality.

Progressive pulmonary fibrosis (PPF) is a clinical phenotype that can occur across multiple interstitial lung diseases (ILDs) and is characterized by worsening lung fibrosis over time despite treatment of the underlying disease. As fibrosis progresses, patients may experience decline in lung function accompanied by worsening breathlessness during exercise and daily activities. Over time, disease progression can lead to significant disability, respiratory failure, and premature death.

Idiopathic pulmonary fibrosis (IPF) is a chronic, progressive lung disease characterized by irreversible scarring of the lungs and a continual decline in lung function. Patients commonly experience worsening shortness of breath and persistent cough, which can significantly impact daily activities and quality of life.

Insmed Incorporated 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 is advancing a diverse portfolio of approved and mid- to late-stage investigational medicines — including two approved therapies to treat chronic, debilitating lung diseases — as well as cutting-edge drug discovery focused on serving patient communities where the need is greatest. Insmed's commercial portfolio and clinical pipeline are organized around three therapeutic areas: Respiratory, Immunology & Inflammation, and Neuro & Other Rare. The Company's research engine is advancing a wide range of technologies and modalities, including gene therapy, AI-driven protein engineering, RNA end-joining, and synthetic rescue, in the pursuit of future pipeline candidates.

Headquartered in Bridgewater, New Jersey, Insmed has offices and research locations throughout the United States, Europe, and Japan. Visit www.insmed.com to learn more or follow us on LinkedIn, Instagram, YouTube, and X.

This press release contains forward-looking statements that involve substantial risks and uncertainties. "Forward-looking statements," as that term is defined in the Private Securities Litigation Reform Act of 1995, are statements that are not historical facts and involve a number of risks and uncertainties. Words herein such as "may," "will," "should," "could," "would," "expects," "plans," "anticipates," "believes," "estimates," "projects," "predicts," "intends," "potential," "continues," and similar expressions (as well as other words or expressions referencing future events, conditions or circumstances) may identify forward-looking statements.

The forward-looking statements in this press release are based upon the Company's current expectations and beliefs, and involve known and unknown risks, uncertainties and other factors, which may cause the Company's actual results, performance and achievements and the timing of certain events to differ materially from the results, performance, achievements or timings discussed, projected, anticipated or indicated in any forward-looking statements. Such risks, uncertainties and other factors include, among others, the following: failure to successfully conduct the Company's current and future clinical trials for TPIP, including due to the Company's potential inability to enroll or retain sufficient patients to conduct and complete the trials or generate data necessary for regulatory approval, among other things; development of unexpected safety or efficacy concerns related to TPIP; failure of third parties on which the Company is dependent to manufacture sufficient quantities of TPIP for clinical needs, to conduct the Company's clinical trials, or to comply with the Company's agreements or laws and regulations that impact the Company's business or agreements with the Company; failure to obtain regulatory approval for TPIP in any or all of the indications for which approval is being sought; inaccuracies in the Company's estimates of the size of the potential markets for TPIP or in data the Company has used to identify physicians; expected rates of patient uptake, duration of expected treatment, or expected patient adherence or discontinuation rates, if TPIP is approved; inability of the Company or the Company's third-party manufacturers to comply with regulatory requirements related to TPIP; the Company's inability to obtain adequate reimbursement from government or third-party payors for TPIP or acceptable prices for TPIP, if approved; restrictions or other obligations imposed on the Company by agreements related to TPIP and failure to comply with the Company's obligations under such agreements; risks that the Company's clinical studies will be delayed or that serious side effects will be identified during drug development; the strength and enforceability of the Company's intellectual property rights or the rights of third parties; and the cost and potential reputational damage resulting from litigation to which the Company may become a party, including product liability claims.

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