4DMT Presents Positive Interim Data from Aerosolized 4D-710 Phase 1/2 AEROW Clinical Trial in Patients with Cystic Fibrosis at the ECFS 46th Annual Meeting

• Reported data from cohort 1 (n=3, 1E15 vg dose) of cystic fibrosis modulator treatment ineligible/intolerant participants with 9-12 months follow-up
  

• Quality of life outcomes measured by Cystic Fibrosis Questionnaire-Revised respiratory symptom score (CFQ-R-R) meaningfully improved for all three participants
  

• Percent predicted forced expiratory volume in one second (ppFEV₁) meaningfully improved in participant with moderate ppFEV₁ impairment at baseline; ppFEV₁ maintained stable in participants with normal or mild impairment at baseline
  

• Bronchoscopy sample results demonstrated widespread and consistent expression of the cystic fibrosis transmembrane conductance regulator (CFTR) transgene protein in 92-99% of lung airway cells, at levels significantly above normal control lung tissues
• Dose selection and initiation of Phase 2 Dose Expansion stage expected in H2 2023; additional interim data including for cohort 2 participants (2E15 vg dose) expected at the North American Cystic Fibrosis Conference in November 2023
• Company to host live webcast today at 4:30 p.m. ET with cystic fibrosis specialist Dr. Jennifer L. Taylor-Cousar

EMERYVILLE, Calif., June 07, 2023 (GLOBE NEWSWIRE) -- 4D Molecular Therapeutics (Nasdaq: FDMT, 4DMT, or the Company), a clinical-stage biotherapeutics company harnessing the power of directed evolution for targeted genetic medicines, today announced positive interim clinical data from the 4D-710 Phase 1/2 AEROW clinical trial for the treatment of cystic fibrosis lung disease. 4D-710 is comprised of our targeted and evolved vector, A101, and a codon-optimized CFTR∆R transgene and is designed for aerosol delivery to achieve CFTR expression within lung airway epithelial cells. In this clinical update, participants ineligible for (n=2) or intolerant of (n=1) existing CFTR modulators were dosed with 4D-710 in cohort 1 (dose 1E15 vg) and showed meaningful improvement in cystic fibrosis-related quality of life measured by CFQ-R-R and improved or stabilized ppFEV₁. Interim data from the study will be presented in an oral presentation titled, “AAV mediated gene therapy for cystic fibrosis: Interim results from a Phase 1/2 clinical trial,” at the European Cystic Fibrosis Society (ECFS) 46th Annual Meeting held in Vienna, Austria on Thursday, June 8 at 5:00 p.m. CET (11:00 a.m. ET).