Insmed Retires the Scoreboard — and Asks to Be Valued on Epidemiology
BRINSUPRI's $400 million quarter is buried under a 47% drawdown, a metric blackout, and a fight with the KOLs about how many bronchiectasis patients actually exist
INSM · Earnings Call · 2026-10-29
A blockbuster with a drawdown problem
On the numbers, this was the quarter a launch-stage biotech spends a decade dreaming about. BRINSUPRI produced $400.1 million in its fifth full quarter, up 29% sequentially; ARIKAYCE added $124.4 million, up 9% year over year. Together roughly $525 million of revenue in ninety days, against the $425 million booked in the July quarter — a 296% year-over-year jump on the last filed quarter. Guidance went up for both products: BRINSUPRI to $1.35–1.4 billion for the year, ARIKAYCE to $460–470 million.
Revenue has compounded from a $93 million quarter in early 2025 to $425 million by July 2026, and the mix shift is doing what mix shifts are supposed to do — gross margin has climbed from 74% two years ago to a company-reported 85.1% this quarter (cost of product revenue was 14.9% of sales, down from 20.6% a year ago).
And yet the stock sits 47.2% below its December 2025 peak of $211.41, up only 7.9% over the last ninety days and 17.2% off an August high. Roughly $24.4 billion of market cap against $1.81–1.87 billion of 2026 guidance works out to something near 13x forward sales — a multiple that says the market is already discounting a great deal of the story. That gap between operating reality and the tape is the real subject of this call.
The vocabulary changed, and so did the unit of analysis
For four consecutive quarters, Insmed spoke in prescription language. New patient starts, continuation rate, refill timing, prescriber breadth versus depth, organic demand — these were the top-ranked themes of the May and August calls, and management fed them out quarter by quarter with unusual generosity.
This quarter, they were retired. “As previously communicated, now that we are past the first full year of launch, we no longer plan to provide specific updates to each individual launch metric.” — Will Lewis, CEO · 2026-10-29 Pressed three separate times — by Evercore, by Jefferies, by Goldman — Will Lewis offered reassurance rather than data: “I would tell you all of the metrics are positive from my point of view” — Will Lewis, CEO · 2026-10-29, adding that observers should watch Symphony TRx data instead.
That is a genuine loss of visibility, and the sell-side noticed. But the replacement vocabulary says more than the retired one did. The new top-ranked themes for the company are center of excellence, patients with COPD, and comorbid patient populations. The unit of analysis has moved from prescriptions shipped to bodies undiagnosed.
Lewis is unambiguous about why: the comorbid opportunity is “without a question of a doubt, the biggest opportunity sitting within Insmed today” — Will Lewis, CEO · 2026-10-29. The mechanics are a second launch inside the company — a dedicated task force, sixteen disease-educator nurses deployed across U.S. pulmonology practices, retrospective CT-scan mining at three COPD/asthma centers, and early-stage AI diagnostic tools being built with partners to flag bronchiectasis inside existing hospital software. No new clinical trial is required, because any patient with a confirmed bronchiectasis diagnosis is already on label.
Patients feel better on it in many occasions, and the consequence of that is you really should be thinking about this for your broader populations... He slapped me on the shoulder and said, 'How does it feel to have a statin for the lungs?'
The disagreement worth paying attention to
Here is the most useful friction on the call. TD Cowen's Ritu Baral pushed back directly: her KOLs do not believe the undiagnosed comorbid population is nearly as large as the company's framing implies. Lewis's response leaned on published literature — “between 4% and 64% of COPD patients, this is in published literature, are comorbid with bronchiectasis. At the low end of that range, that would be 800,000 patients” — Will Lewis, CEO · 2026-10-29 — and on a modified GOLD guideline recommending high-res CT scans for COPD patients still exacerbating on max therapy. He conceded the number will only be nailed down over the next year.
That is the crux: a 4%-to-64% range is not an estimate, it is a hypothesis. Management is asking investors to fund a re-rating on an epidemiological claim that the company itself says it will be able to quantify only by mid-2027, and that some key opinion leaders dispute outright.
The adjacencies are new too. Japanese patients appeared as the company's single highest-ranked theme, reflecting last week's BRINSUPRI launch in Japan — roughly 150,000 diagnosed patients, and a striking 68% annualized exacerbation reduction in the ASPEN subpopulation versus roughly 20% globally. Management expects Japan to be the main driver of ex-U.S. sales, with the usual 10–15% of global peak.
The $14 billion claim and what backs it
Peak sales guidance has been on a steep climb. In August, BRINSUPRI's peak estimate rose from $5 billion to $7 billion. This quarter it became a portfolio figure: more than $14 billion collectively across three respiratory assets, with BRINSUPRI above $7 billion, TPIP above $6 billion, and ARIKAYCE above $1 billion — and with the COPD/asthma comorbid population explicitly excluded from the BRINSUPRI number.
The pipeline support is real. PALM-ILD is more than 35% enrolled and, per Lewis, "about six months ahead of schedule"; PAH has its first patient; PPF has its first site; IPF initiates in the first half of 2027. ARIKAYCE's supplemental NDA has priority review with a PDUFA date of January 28, 2027, and no advisory committee planned — a label expansion that would take the addressable pool from roughly 15,000 to more than 100,000 patients per region.
The bill for all of it
What has not changed is the burn. Combined R&D and SG&A rose 40% year over year as launch spending and four Phase III TPIP trials ramp simultaneously. Research and development consumed about half of July-quarter revenue, and the TPIP manufacturing build now flips into clinical-trial spend.
Effective net cash of $1.2 billion in July is down 35% year over year and 50% from the 2025Q3 peak, with free cash flow still negative at $136 million for the quarter. Sara Bonstein put cash approximately $1.1 billion at quarter-end and reaffirmed cash flow positivity in 2027 — but she is leaving. Lewis publicly thanked her for "the creation and management of our internal financial architecture," which means the promise and the person who built the model behind it are separating.
One specific new headwind deserves a line: under the IRA small-manufacturer phase-in, Insmed's Medicare catastrophic coverage cost on ARIKAYCE rises from 1% to 5% in 2027 and ratchets annually to 20% by 2031. Gross-to-net is drifting structurally upward, not downward.
The read: Insmed has a genuine first-in-disease franchise, a clean line of sight to profitability, and a plausible second act in undiagnosed COPD comorbidity. What it no longer has is a quarterly scoreboard — and the market, having de-rated the stock 47% from its high, is not obviously wrong to want one back.