Roche ended two Ionis-partnered Huntington’s studies after late-stage outcomes failed to meet key efficacy goals, handing Ionis fresh clinical and commercial pressure. Roche discontinued the Phase 2 GENERATION HD2 study of tominersen and also stopped further evaluation of RG6496 based on new data from a parallel animal study. Roche told the Huntington’s community that the decisions were “data-driven” and reflected the “totality of data,” even as it called the timing “deeply disappointing.” Tominersen is an antisense therapy that reduces huntingtin expression, while RG6496 is designed to be more selective by binding mutated huntingtin RNA. The news follows recent setbacks in Roche–Ionis collaboration elsewhere, including Ionis’ reported troubles tied to a separate Wainua program with AstraZeneca in transthyretin amyloidosis cardiomyopathy. Roche and Ionis said they will continue other collaboration programs, but the Huntington’s pullback underscores the volatility of the antisense pipeline in late-stage neurology.