Insmed (INSM) Shares Surge 2.85% on FDA Approval of Brinsupri for NCFB

Insmed (INSM) shares climbed 2.85% on Thursday, extending their winning streak to six consecutive sessions with a cumulative gain of 15.91%. The stock reached an intraday high of $145.39, marking its highest level since October 2025, as investor sentiment remained buoyed by recent corporate developments.

The surge follows the U.S. Food and Drug Administration’s (FDA) approval of Brinsupri (brensocatib) in September 2025 as the first therapy for non-cystic fibrosis bronchiectasis (NCFB), a condition lacking prior FDA-approved treatments. This milestone has positioned Insmed as a leader in respiratory medicine, unlocking a multi-billion-dollar market opportunity and reinforcing Brinsupri’s role as a cornerstone of the company’s growth strategy.

Analyst optimism has further fueled the rally, with several brokerages upgrading price targets. TD Cowen raised its target to $193 from $154, while Jefferies and JPMorgan also increased their estimates. These upgrades were driven by Brinsupri’s approval and promising Phase 2 data for TPIP, an inhaled therapy for pulmonary hypertension. Positive clinical results, including a 35% reduction in pulmonary vascular resistance and a 35.5-meter improvement in six-minute walk distance, have underscored TPIP’s potential to capture a significant share of the $5 billion pulmonary hypertension market.

Institutional investors have bolstered their stakes in Insmed, reflecting confidence in its transition from a development-stage biotech to a diversified growth company. However, insider selling has introduced mixed signals, with key executives reducing holdings. Analysts caution that while such activity may reflect portfolio diversification, it remains a factor to monitor amid broader market optimism.

Insmed’s existing commercial foundation, anchored by Arikayce for NTM lung disease, continues to provide stable revenue, with sales growing 21% year-over-year in Q2 2025. This cash flow supports R&D and commercialization efforts for Brinsupri and TPIP, reinforcing the company’s ability to scale. With a 12-month total return of 127.64% compared to the S&P 500’s 14.18%, Insmed’s premium valuation reflects high expectations, though risks such as regulatory delays and high R&D costs remain.