Insmed's stock experienced a sharp intraday plummet of 15.98% on Thursday, reflecting significant investor concern following the release of the company's first-quarter financial results.

The decline was primarily driven by the company's key lung disease treatment, Arikayce, missing first-quarter sales expectations. Arikayce generated revenue of $98.1 million, falling short of the average analyst expectation of $105.4 million. Furthermore, the company indicated that evolving U.S. policies are being evaluated for their potential impact on the international launch timing for its other lung disease treatment, Brinsupri, adding to market uncertainty.

While Insmed reported a narrower quarterly loss per share of $0.76 compared to an expected loss of $0.96, and total revenue of $306 million beat estimates, the market reaction highlighted investor focus on the sales miss for a core product and concerns over the company's ongoing substantial net losses, which totaled $163.6 million for the quarter.