Avidity Biosciences (RNA) Earnings Call Presentation

Del-brax Development and Regulatory Pathway - FDA has confirmed an accelerated approval pathway for delpacibart braxlosiran (del-brax) in the US [8] - The primary endpoint for accelerated approval is the reduction in the circulating biomarker cDUX [10, 59, 76] - A global confirmatory Phase 3 FORWARD trial has been initiated with 200 participants in a 1:1 randomized, double-blind, placebo-controlled design [10, 79] - The company anticipates topline data from the biomarker cohort of the FORTITUDE trial in Q2 2026 and a BLA submission in H2 2026 [10, 74] - The confirmatory Phase 3 FORWARD trial is designed to support full approval, with approximately 45 global sites [80, 83] FORTITUDE Trial Data - 12-month topline data from the FORTITUDE trial showed improved functional mobility in del-brax treated participants compared to placebo, as measured by 10MWRT and TUG [35, 39, 57] - Participants treated with del-brax also demonstrated improved muscle strength measured by QMT and improved upper limb function measured by RWS compared to placebo [42, 44, 57] - Del-brax showed a favorable long-term safety and tolerability profile in the FORTITUDE trial and its open-label extension (OLE) [10, 19, 57] - Over 60% of patients express that slowing or stopping the loss of muscle function would be the most meaningful outcome [30] cDUX Biomarker - cDUX is elevated 6- to 9-fold in people living with FSHD compared to healthy volunteers [59] - Del-brax treatment resulted in rapid and statistically significant reductions in cDUX and creatine kinase (CK) levels [59, 64]