On April 24, 2025 — GenAssist Ltd (GenAssist) announced meaningful functional improvements in the second patient in the ongoing IIT study of groundbreaking DMD base editing drug GEN6050X after the reported positive response from the first patient. Up to date, two patients have finished 6 months follow-up. Dosing of a third patient is underway.
The summary of two patients’ safety and efficacy outcomes is as following.
- Favorable Safety Profile: Only transient and manageable serious adverse events were observed, with no hepatic toxicity or suspected unexpected serious adverse reactions. All adverse events were resolved within the scheduled two-week inpatient period. Both patients had no clinically significant symptoms or laboratory abnormalities during follow-up.
- 6-months Efficacy Data:
The first patient demonstrated 1 point increase on the North Star Ambulatory Assessment (NSAA), 3 points gain on the Performance of Upper Limb scale 2.0 (PUL2.0)—driven by improvements in both shoulder (+1) and distal hand/wrist (+2)—and an increase of over 100 meters in the 6-Minute Walk Test.
The second patient showed 3 points gain in NSAA, 1 point improvement on PUL 2.0 at the distal hand/wrist level, 0.5s improvement in 10-meter walk time.
Improvements in cardiac function were observed in both patients. The first patient, who had dilated cardiomyopathy, showed 12% increase in left ventricular ejection fraction (LVEF)* and 7% increase in left ventricular fractional shortening (LVFS). The second patient, who had normal cardiac function at baseline, exhibited 10% increase in LVEF and 7% increase in LVFS.
*Increase for LVEF was determined by M-mode in echocardiography.
“These mid–term results reinforce GEN6050X’s potential as a transformative base editing therapy for DMD,” said Dr. Chunyan He, CEO of GenAssist. “We will present these exciting findings at the Annual Meeting of the American Society of Gene & Cell Therapy (ASGCT), where we look forward to exchanging insights with peers and experts on treating DMD.”
The 28th ASGCT Annual Meeting will take place from May 13–17, 2025 in New Orleans, Louisiana, at the Ernest N. Morial Convention Center. As the world’s largest and most authoritative conference in gene and cell therapy, this event is expected to draw over 3,500 global professionals, including scientists, clinicians, industry leaders, and patient advocates, to share breakthroughs and collaborate on advancing transformative therapies.
About GEN6050X
GEN6050X is the global first intravenous base editing therapy for DMD, which targets patients amenable to exon 50 skipping. The action mechanism of GEN6050X includes base editor-mediated exon skipping to restore dystrophin expression and ACTG1 overexpression to enhance the cytoskeleton and improve muscle function.
The IIT study is being conducted at Peking Union Medical College Hospital (NCT06392724) since August 2024. GEN6050X received FDA IND approval on March 6, 2025. GenAssist is preparing to initiate Phase I clinical trial in US.
