FDA-Approved Insmed Drug Drives 0.54 Stock Drop as 280M Volume Ranks 391st Long-Term Growth Hopes Face Reimbursement and Adoption Risks

On August 22, 2025, Insmed (INSM) closed down 0.54% with a trading volume of $280 million, ranking 391st among U.S. stocks by volume. The decline followed mixed market sentiment around the company’s recent FDA-approved drug for a niche respiratory condition.

The U.S. Food and Drug Administration cleared Insmed’s Brinsupri (brensocatib) as the first oral, daily treatment for non-cystic fibrosis bronchiectasis (NCFB) in adults and children aged 12 and older. The approval grants access to approximately 500,000 diagnosed patients in the U.S., with distribution limited to specialty pharmacies like Maxor Specialty Pharmacy. While the milestone strengthens Insmed’s long-term growth narrative, analysts note uncertainties around payer reimbursement policies and market adoption rates. The company’s strategic reliance on Brinsupri’s U.S. launch remains its most critical near-term catalyst.

Projections indicate Insmed could generate $1.9 billion in revenue and $293.8 million in earnings by 2028, assuming a 72% annual revenue growth rate. However, current forecasts imply a 9% downside to its valuation, with fair value estimates ranging from $120 to over $21,000 per share. Divergent market views highlight the need for investors to assess both the drug’s commercial potential and regulatory risks.

The strategy of buying the top 500 stocks by daily trading volume and holding them for one day resulted in a total profit of $2,253.88 from December 2022 to August 2025. The approach recorded a maximum drawdown of -$1,025.71 and a Sharpe ratio of 1.47, reflecting moderate returns with favorable risk-adjusted performance.