INSM - KOLs Share Contrasting Views On Brinsupri's Outlook: Key Takeaways From Our Calls

Research evidence excerpt

INSM - KOLs Share Contrasting Views On Brinsupri's Outlook: Key Takeaways From Our Calls

Truist Securities

Equity Research Report May 18, 2026

HEALTHCARE: Biotech Insmed Incorporated (INSM)

INSM - KOLs Share Contrasting Views On Brinsupri's Outlook: KeyDanielle Brill, Pharm.D.

212-303-4110 Takeaways From Our Calls

Danielle.Brill@truist.com

Alex Nackenoff, Ph.D. We hosted two high-volume bronchiectasis KOLs to gather perspectives on Brinsupri’s

212-590-0908 current role in clinical practice & expectations for future uptake. Notably, the KOLs expressed

Alex.Nackenoff@truist.com somewhat divergent views, which we believe broadly reflect the prevailing bull vs bear

debate on the Street.

Our take: Our doc feedback to-date has skewed modestly positive, though we acknowledge

Stock Rating BUY the limited sample size. Broadly, it remains early to draw definitive conclusions on Brinsupri’s

Unchanged impact, as physicians need more follow-up time to assess for improvements on exacerbation

rates & lung function. It does appear large tertiary centers have already prescribed for most

Price Target $185.00 eligible patients.

Unchanged

Brinsupri prescribing trends

TR to Target 69.5% KOL #1 (Bear):

Price (May 15, 2026) $109.14 • Manages ~350 bronchiectasis patients; ~15-20% are good candidates for Brinsupri

52-Wk Range $211.41-$66.02 based on criteria of severe symptoms/ 2+ exacerbations per year.

Market Cap ($M) $23,656 • Counsels patients that efficacy is modest

ADTV 1,965,681 • To-date, has prescribed Brinsupri for ~25-30 patients; 23 received drug; 20 patients still

Shares Out (M) 217 on therapy

Short Interest Ratio/% Of Float 6.9%

• 3 discontinuations driven by AEs (n=2) and perceived ineffectiveness (n=1); currentEnterprise Value ($M) $23,137 discontinuation rate 13%