Shares of 4D Molecular Therapeutics rose after the company reported positive two-year follow-up data from its PRISM Phase 1/2 trial, including results from a Phase 2b cohort studying its gene therapy candidate 4D-150 for wet age-related macular degeneration. The update emphasized durability of visual and retinal outcomes alongside a reduced need for supplemental anti-VEGF injections, a key investor focus in a space driven by long-term treatment burden.
Key takeaways
- Price move: 4D Molecular Therapeutics shares closed at $10.99 on Friday, up 1.38%.
- Catalyst: The company released two-year data from the PRISM trial, including Phase 2b results for 4D-150 in patients with wet age-related macular degeneration.
- Durability: The therapy maintained best corrected visual acuity and central subfield thickness through two years.
- Treatment burden reduction: The overall Phase 2b cohort saw a 78% reduction in treatment burden versus projected on-label aflibercept dosing, with fewer supplemental injections.
- Safety profile: Across 71 patients in PRISM Phase 1/2a and Phase 2b, mild, transient intraocular inflammation was reported in 2 patients, with no new cases later in follow-up.
What the two-year PRISM results show
4D-150 is an investigational adeno-associated virus (AAV)-based gene therapy designed to support sustained retinal production of aflibercept and anti-VEGF-C after a single intravitreal injection. The company is aiming to reduce the frequency of anti-VEGF treatments that are typically required for wet age-related macular degeneration and diabetic macular edema.
In PRISM, the Phase 1/2 trial is a dose-escalation, randomized, placebo-controlled extension study in adults with wet AMD. Safety and tolerability are the primary endpoints, while secondary measures include the number of supplemental aflibercept injections over 52 weeks and changes in best corrected visual acuity (BCVA) and central subfield thickness (CST).
For the Phase 2b cohort, 45 patients received a single intravitreal dose of 4D-150 at either 3E10 or 1E10 vector genomes per eye. The 3E10 dose was selected as the study dose for the Phase 3 4FRONT-1 and 4FRONT-2 trials.
Durability and treatment burden were central to the update
According to the company, through two years, 4D-150 maintained BCVA and retinal thickness (CST) while delivering a durable reduction in treatment burden. The company highlighted results from both the overall Phase 2b cohort and a subset of patients recently diagnosed within six months.
- Overall Phase 2b cohort: Treatment burden was reduced by 78%. Patients required 2.7 supplemental injections versus 12 projected injections based on on-label aflibercept dosing of 2 mg every eight weeks.
- Recently diagnosed subgroup: Treatment burden reduction was reported at 87%, with patients requiring an average of 1.6 supplemental injections.
The company also said a dose-response favoring the Phase 3-selected dose (3E10 vg/eye) was maintained, supporting the rationale for advancing that specific dose into late-stage studies.
Safety follow-up: limited early inflammation, no new cases later
The PRISM update also focused on tolerability and longer-term ocular safety. FDMT reported a favorable safety profile across 71 patients who participated in PRISM Phase 1/2a and Phase 2b. Only 2 of 71 patients, or 2.8%, experienced mild, transient intraocular inflammation within the first 28 weeks after dosing.
Further follow-up reportedly showed no new inflammation cases during more than four years of monitoring. The company said it did not observe treatment-related hypotony, endophthalmitis, retinal vasculitis, or choroidal effusions.
Market reaction and what investors will watch next
FDMT shares closed at $10.99 on Friday (17.07.2026), up 1.38%, and were trading higher in pre-market activity, indicating that investors were reacting positively to the durability and treatment-burden message. The magnitude of the reported reduction in supplemental injections—and the consistency of outcomes through two years—directly addresses one of the main hurdles in retinal gene therapy: demonstrating sustained benefit that translates into fewer clinic visits and fewer repeat therapies.
With Phase 3 4FRONT-1 and 4FRONT-2 ongoing for wet AMD, the key near-term question for investors is whether the Phase 2b durability signal and safety profile hold up as the program scales. Upcoming updates from Phase 3 enrollment progress, interim efficacy and safety readouts, and continued monitoring of ocular inflammation and other adverse events will likely shape expectations for how 4D-150 could compete in a treatment landscape dominated by frequent anti-VEGF dosing.
