4D Molecular announce update on regulatory interactions, development for 4D-710

4D Molecular Therapeutic announced an update on its regulatory interactions and development path for 4D-710, an aerosolized genetic medicine for the treatment of CF lung disease. Given high-level cystic fibrosis transmembrane conductance regulator transgene expression in all lung airway biopsies disclosed to date, dose exploration continues with the evaluation of lower doses in the 4D-710 Phase 1/2 AEROW clinical trial in pwCF dosed at 5E14 vg and 2.5E14 vg; nine pwCF total have been dosed to date. Phase 2 Expansion Cohort dose selection is expected in Q2 2024 based on all clinical and lung biopsy data; the Company anticipates enrolling a total of six to nine pwCF in the Phase 2 Expansion Cohort. The Company submitted an AEROW trial amendment to the Cystic Fibrosis Therapeutics Development Network as follows: 1) to enroll pwCF with lower baseline percent predicted forced expiratory volume in 1 second to assess ppFEV1 response to 4D-710, and 2) to add a second lung biopsy procedure at a longer-term timepoint to study long term durability of 4D-710 CFTR transgene expression and optimal timing for redosing. In addition, the Company recently had discussions with the U.S. Food and Drug Administration and European Medicines Agency, regarding the registrational path for 4D-710 for treatment of CF lung disease in pwCF who are ineligible for or cannot tolerate approved CF modulator therapies. With regards to a full product approval in this patient population, the Company anticipates a Phase 3 randomized, controlled pivotal study enrolling approximately 60-80 pwCF with low baseline ppFEV1. Given the high unmet need in this CF population, an accelerated approval path may be feasible. The Company intends to have discussions with the FDA and EMA on an accelerated approval pathway, in parallel with Phase 3 planning, following additional AEROW clinical and lung biomarker data in pwCF with low baseline ppFEV1.