Why Blueprint cannot afford another Gavreto

One of Blueprint’s two US-approved drugs, Gavreto, is a dud, but the push is on to talk up prospects of the second, Ayvakit. The latter is approved in a subset of gastrointestinal stromal tumours and in advanced systemic mastocytosis, but the key to hitting the sellside’s 2028 revenue target of $1.2bn, according to Evaluate Pharma, lies in the indolent form of systemic mastocytosis. Yesterday Blueprint unveiled full data from Ayvakit’s Pioneer study in indolent disease that is the basis of an FDA approvability decision by May 22. A first look at the data, last August, caused concerns over a large placebo effect, but Blueprint has now shown that crossing placebo patients to active drug prompts further symptom reduction. And breaking down the primary endpoint, total symptom score, could dispel fears that efficacy was mostly being driven by skin improvements. Still, Blueprint’s 3% stock uptick today suggests lingering doubts over whether rare disease pricing is achievable in what would be a much broader Ayvakit use. Blueprint cannot afford another Gavreto, whose 2026 forecasts have fallen from $832m to $315m, and which made Roche’s list of recent write-offs before the companies’ 2020 deal was terminated on Thursday.