Cabaletta Bio said new data from its rese-cel autoimmune program showed that 8 of 10 evaluable dermatomyositis and antisynthetase syndrome patients in the phase 1/2 Reset-Myositis study would have met the registrational primary endpoint, with 5 of 6 dermatomyositis patients posting an immunomodulator-free moderate-to-major total improvement score response at 16 weeks. All five maintained that response through the latest follow-up, which extended as long as 1.5 years.
The company also reported that the first juvenile dermatomyositis patient achieved an immunomodulator-free moderate response at 16 weeks and remained in response through 32 weeks. Cabaletta said 83% of the dermatomyositis patients in the cohort would have met the primary endpoint, and 75% of antisynthetase syndrome patients met the same immunomodulator-free response bar at 16 weeks.
In systemic sclerosis, Cabaletta said phase 1/2 patients showed improving skin and lung disease activity over time. Among patients with interstitial lung disease at screening, the median improvement in percent predicted FVC was 7.5% at 36 weeks. At that same point, 5 of 6 patients met the revised composite response index in systemic sclerosis-25 and 4 of 6 met the rCRISS-50 threshold, while remaining off all immunomodulators and off or tapering steroids.
Safety counts in the myositis and systemic sclerosis cohorts were also reported. In Reset-Myositis, all 17 patients experienced either no CRS or transient grade 1 fever, and no ICANS was observed. In Reset-SSC, 13 of 15 patients had either no CRS or transient grade 1 fever, and 14 of 15 had no ICANS.
Cabaletta said the first two preconditioning-free lupus patients showed early activity at the lowest dose tested. One had deep B-cell depletion, while the second showed about a 90% reduction in peripheral B cells. One of the two had grade 1 CRS and neither had ICANS.
In the preconditioning lupus cohorts, 6 of 8 patients with 12 months of follow-up met the definition of remission in SLE while staying off immunomodulators for the full follow-up period. The market has reacted to these announcements by moving the company's shares -1.63% to a price of $3.62. Check out the company's full 8-K submission here.
