PepGen Stock More Than Doubles on Phase 2 Data Showing Record Splicing Correction in Rare Muscle Disease

PepGen shares surged more than 114% in premarket trading on November 10 after the company reported positive topline results from the 10 mg/kg dose cohort of its Phase 2 FREEDOM2-DM1 trial evaluating PGN-EDODM1 in patients with myotonic dystrophy type 1, a rare, progressive genetic disease. The trial achieved a 46.5% mean splicing resolution at Week 13 compared with 6.8% for placebo, a level PepGen described as the highest reported splicing correction in DM1, alongside improvements across multiple functional measures.

PGN-EDODM1 is an Enhanced Delivery Oligonucleotide designed to disrupt pathogenic DMPK hairpin structures while preserving normal DMPK function, an approach distinct from therapies that degrade DMPK RNA. The drug holds FDA Orphan Drug and Fast Track designations as well as European Medicines Agency Orphan Designation. The treatment was generally well tolerated with no serious adverse events or dose-limiting toxicities reported, though minor renal findings were observed. Data from the highest 12.5 mg/kg cohort are expected in the first half of 2027.

Also on November 10, Beam Therapeutics reported that its BEACON Phase 1/2 trial of risto-cel in sickle cell disease achieved its primary efficacy endpoint, defined as freedom from severe vaso-occlusive crises for at least 12 consecutive months, based on independently adjudicated results at a prespecified interim analysis. The trial also met all primary safety endpoints, though Beam shares edged down roughly 1.9% in premarket trading.