Insmed's inhaled PAH therapy shows durable efficacy in 12-month extension, bolstering $6B sales outlook

Insmed reported that its inhalable prostanoid candidate, treprostinil palmitil inhalation powder (TPIP), maintained functional and biomarker benefits through a 12‑month open‑label extension in patients with pulmonary arterial hypertension (PAH). The extension enrolled more than 90 participants who were either continuing TPIP from earlier studies or switching from placebo, and was designed to follow them for up to 24 months.

At the 12‑month mark, patients who stayed on TPIP improved their six‑minute walk distance by an average of 55.7 meters, while those who crossed over from placebo showed a similar 54.1‑meter gain. Biomarker levels, including NT‑proBNP, also trended downward, indicating sustained disease control.

Guggenheim Partners analysts described the data as "impressive" and said it strengthens the case for TPIP as a best‑in‑class inhaled prostanoid. They project peak sales of the product to exceed $6 billion across several planned indications, with PAH being the primary target.