U.S. Bio Executive Realizes Stock Option Gains Worth Millions Amid Positive MAC Lung Disease Treatment News

William Lewis, CEO of U.S. biotech company Insmed Inc. (Nasdaq: INSM), exercised two tranches of stock options on March 5 to acquire approximately 10,000 common shares, then sold the entire holding on the open market at prices ranging from about $144 to $148 per share, netting roughly $1.56 million (approximately ₩2.1 billion). On March 30, the company’s General Counsel similarly exercised options to acquire about 19,000 shares and sold them at $150.98 per share, realizing approximately $2.97 million (around ₩4.0 billion). Both transactions were conducted pursuant to pre-established Rule 10b5-1 trading plans.

Despite his recent sale, Lewis continues to directly hold more than 300,000 Insmed common shares, representing an equity stake valued at about $44 million (roughly ₩60 billion) at current market prices.

On March 23, Insmed announced positive topline results from its Phase 3b ENCORE study of ARIKAYCE (amikacin liposome inhalation suspension) in treatment-naïve patients with Mycobacterium avium complex (MAC) lung disease. At 13 months, the ARIKAYCE combination regimen met the primary endpoint of improved respiratory symptom scores and showed statistically significant advantages over the control arm in both culture-negative conversion rate and durability of response.

Based on these data, the company plans to submit an additional New Drug Application (NDA) in the second half of 2026 to convert ARIKAYCE’s current accelerated approval into full approval in the U.S. It also aims to pursue a label expansion in the U.S. and Japan, potentially extending the indication from the roughly 30,000 patients with refractory MAC to more than 200,000 MAC lung disease patients overall.

Separately, in its February 19 financial update for fourth-quarter and full-year 2025, Insmed reported continued revenue growth for ARIKAYCE and provided an early sales outlook for BRINSUPRI (brensocatib), its non-cystic fibrosis bronchiectasis therapy launched in the U.S. in 2025. The company also reaffirmed its development plans for late-stage pipeline candidates, including inhaled treprostinil palmitil (TPIP).

Headquartered in Bridgewater, New Jersey, Insmed is a global biopharmaceutical company focused on rare and serious pulmonary diseases. In addition to ARIKAYCE, it markets DPP-1 inhibitor BRINSUPRI and is advancing multiple respiratory programs, including TPIP for pulmonary hypertension and interstitial lung disease.