Gene Therapy 4D-150 Enters Phase 3 Trial to Tackle Diabetic Eye Disease
4DMT launches a 514-patient global Phase 3 trial for its gene therapy 4D-150, targeting vision loss from diabetic macular edema.
Summary
4DMT has enrolled the first patients in its 4SIGHT Phase 3 trial testing 4D-150, a gene therapy for diabetic macular edema (DME) — a leading cause of vision loss in people with diabetes. The trial will enroll 514 treatment-naïve patients and compare 4D-150 against the standard-of-care drug aflibercept. Early two-year data from 22 patients showed meaningful vision gains (average +10.8 letters), significant reductions in retinal fluid, and a clean safety record with no serious eye-related adverse events. Crucially, patients receiving 4D-150 needed far fewer supplemental injections than those on standard aflibercept dosing. The therapy holds FDA Regenerative Medicine Advanced Therapy designation, signaling regulatory momentum toward a potential approval.
Detailed Summary
Diabetic macular edema is a serious complication of diabetes in which fluid accumulates in the retina, progressively stealing central vision. It affects an estimated one million Americans and represents a major burden both for patients — who currently require repeated eye injections every six to eight weeks indefinitely — and for the healthcare system. A one-time or infrequent gene therapy could fundamentally change that picture.
4D Molecular Therapeutics (4DMT) has now advanced its lead candidate, 4D-150, into a global Phase 3 trial called 4SIGHT. The randomized, double-masked study will enroll 514 treatment-naïve DME patients and compare 4D-150 against aflibercept 2 mg given every eight weeks, the current standard of care. The primary endpoint is non-inferiority in best corrected visual acuity change at one year, with secondary endpoints targeting treatment burden reduction and improvements in diabetic retinopathy severity.
Supporting the Phase 3 launch, 4DMT reported updated two-year Phase 1/2 data from 22 patients at the Phase 3 dose. Results showed an average vision gain of +10.8 letters, a mean central retinal thickness reduction of 176 micrometers, and no intraocular inflammation or serious ocular adverse events. Patients also required substantially fewer supplemental injections compared with projected on-label aflibercept use — a key quality-of-life advantage.
4D-150 works by delivering genes encoding two anti-VEGF proteins directly into retinal cells via an engineered viral vector, potentially enabling durable, self-sustaining treatment from a single injection. It holds FDA Regenerative Medicine Advanced Therapy designation, and the company reports regulatory alignment with both FDA and EMA toward potential approval filings.
For aging adults, DME risk rises sharply with diabetes duration, making this therapy relevant to the growing population living with long-standing type 2 diabetes. Caveats include the small Phase 1/2 sample size and the absence of peer-reviewed publication of the two-year data; Phase 3 results will be definitive.
Key Findings
- Phase 3 4SIGHT trial enrolling 514 DME patients comparing 4D-150 gene therapy to standard aflibercept injections.
- Two-year Phase 1/2 data show average vision gain of +10.8 letters and 176 µm retinal thickness reduction in 22 patients.
- No intraocular inflammation or serious ocular adverse events reported over two years of follow-up.
- 4D-150 patients needed far fewer supplemental injections than projected standard-of-care recipients.
- 4D-150 holds FDA Regenerative Medicine Advanced Therapy designation, accelerating its regulatory pathway.
Methodology
This is a news report summarizing a company press release announcing Phase 3 trial initiation and updated Phase 1/2 clinical data. The Phase 1/2 dataset is small (N=22) and has not yet been published in a peer-reviewed journal. Evidence quality is preliminary; Phase 3 results will be required to confirm efficacy and safety.
Study Limitations
Phase 1/2 data come from only 22 patients and have not been published in a peer-reviewed journal, limiting independent verification. The comparison to projected on-label aflibercept use — rather than a head-to-head trial arm — introduces potential bias. Phase 3 results at Week 52 and beyond are needed before any conclusions about superiority or long-term durability can be drawn.
Enjoyed this summary?
Get the latest longevity research delivered to your inbox every week.
Enter your email to subscribe: