4DMT declares positive interim Phase I/II data for cystic fibrosis gene therapy

4DMT is advancing to Phase II of its AEROW trial following encouraging interim results for gene therapy 4D710 in cystic fibrosis (CF). Combining an AAV vector with a CFTR transgene, the therapy targets CF patients ineligible for or intolerant of CFTR modulator therapy. CF, a genetic disease impacting 40,000 people in the US, affects multiple organs.

In the Phase I dose exploration stage with ten participants, no adverse events or dose-limiting toxicities occurred in lower and middle dose cohorts. At the highest dose, a prior serious adverse event fully resolved. Lung biopsy results revealed widespread CFTR transgene expression. The 2E15 vg dose was discontinued in favor of the 1E15 vg dose for dose expansion. Enrollment for this phase is set for later this year.

4D-710 received a rare pediatric designation in January 2024, potentially qualifying for a priority review voucher upon FDA approval, valued at around $100 million.