BLA filed on novel surrogate endpoint for fatal orphan disease; FDA acceptance of skin frataxin as the surrogate determines whether approval follows

Larimar is a clinical-stage biotech company developing a protein-replacement therapy for Friedreich's ataxia, a rare, progressive neurological disease with no approved treatment, and the therapy is not yet approved.

Larimar submitted a rolling BLA for nomlabofusp, a frataxin protein-replacement fusion for Friedreich's ataxia, a progressive neurological disease with no approved cure, under accelerated approval using skin frataxin as a novel surrogate endpoint FDA has not previously recognized. Approval hinges on whether FDA grants accelerated approval on that surrogate, with open-label data showing 100% of evaluable participants reaching asymptomatic-carrier frataxin levels and directional mFARS benefit versus a natural history reference. The critical risk is the novel, unvalidated surrogate: a single-arm BLA without a randomized efficacy trial is an unusual approval path, and cash runway extends only to Q3 2027, leaving minimal buffer if the review extends or requires additional data.