Rezolute's oral retinal treatment succeeds in Phase II

Rezolute has announced promising results from a Phase II study of its experimental treatment for diabetic macular edema (DME), RZ402. The study's primary endpoints were effectively met, indicating that the oral drug could be a more convenient alternative to the commonly used anti-VEGF injections, which require intravitreal administration. The positive topline results were disclosed late on Tuesday, leading to a 50% surge in the company's shares during after-hours trading, although the stock later dipped by approximately 6% on Wednesday.

The study involved 94 patients who either had no prior anti-VEGF treatments or had received them only sparingly. Participants were divided to receive daily doses of 50mg, 200mg, or 400mg of RZ402, or a placebo, over a 12-week period. RZ402 is an oral, small-molecule, selective plasma kallikrein inhibitor. The primary efficacy measure focused on the reduction of central subfield thickness (CST) in the retina. All dosage levels of RZ402 demonstrated significant CST reduction compared to the placebo, showing an improvement of approximately 50 microns. Although the response was most pronounced at the 200mg dose, there was no substantial difference between the various dose levels.

JMP Securities analysts commented on the results, highlighting that the treatment has achieved a "clinically meaningful threshold." They also noted the absence of a treatment plateau, suggesting that longer therapy durations might offer additional benefits. Quan Dong Nguyen, a member of Rezolute’s Scientific Advisory Board and a professor at Stanford University, pointed out that the reductions in CST were particularly impressive. He emphasized that retinal thickness is a crucial biomarker for assessing the potential benefits of a therapy for patients with DME. Nguyen believes the data supports the possibility of RZ402 becoming a first-line, non-invasive treatment for DME.

Safety and tolerability of the oral treatment were also confirmed. RZ402 was generally well-tolerated, with adverse events being mild and comparable to those in the placebo group. Importantly, there were no ocular adverse events, a common risk with intravitreal injections. However, the study did not meet its secondary endpoint, which was to improve Best Corrected Visual Acuity (BCVA) compared to the placebo. Analysts pointed out that this was not unexpected, considering the short duration of the study.

Looking ahead, Rezolute plans to seek a partnership to advance the development of RZ402 into late-stage trials. The company believes that collaborating with a partner could maximize the potential of RZ402 not just in the treatment of DME, but also in broader applications.

These encouraging results show that RZ402 could become a significant addition to the treatment landscape for DME, offering a more patient-friendly alternative to current therapies. Further studies will be crucial in determining the long-term benefits and broader applications of this promising treatment.