Rezolute, Inc. announced the completion of enrollment in its RZ402 Phase 2 study in diabetic macular edema (DME). RZ402 is a selective and potent plasma kallikrein inhibitor (PKI) being developed as a potential oral therapy for the chronic treatment of DME. The study is a multi-center, randomized, double-masked, placebo-controlled, parallel-arm study to evaluate the safety, efficacy, and pharmacokinetics of RZ402 administered as a once daily oral monotherapy over a 12-week treatment period and four-week follow-up in participants with DME who are naïve to, or have received limited anti-VEGF injections.

Eligible participants were randomized equally to either a placebo control arm or one of three RZ402 active treatment arms at doses of 50, 200, and 400 mg. This proof-of-concept study was designed to enroll up to 100 participants to evaluate activity and safety by individual dose level and in pooled fashion. In the fourth quarter 2023, based on considerable momentum, the Company elected to keep enrollment open into December to include as many eligible patients as possible.

Screening is now complete, and final study enrollment is expected to be approximately 95 participants. Additionally, although each participant has an assigned study eye, it is expected that a meaningful number of non-study eyes will be eligible for evaluation. Since DME results from a systemic vascular complication associated with diabetes, it commonly affects both eyes.

RZ402, as an orally available systemic therapy, has the potential to treat both eyes simultaneously. As a result of the extension of the enrollment period, the Company now plans to report topline results in the middle of the second quarter 2024, rather than the end of the first quarter 2024. The principal endpoints of the trial include the change in central subfield thickness of the macula, as measured by Spectral Domain Ocular Coherence Tomography, the change in best-corrected visual acuity as measured by the early treatment diabetic retinopathy scale, the repeat dose pharmacokinetics of RZ402 in patients with DME, and the safety and tolerability of RZ402.

DME is a result of a systemic microvascular complication of diabetes, manifesting in the retinal blood vessels behind the eyes, and therefore commonly affects both eyes. With currently available intravitreal anti-VEGF therapies, two separate eye injections are required, or treatment of one eye or both eyes may be deferred, when both eyes are affected. Although a single study eye was identified for primary evaluation, Rezolute plans to take advantage of the binocular exposure that is achieved with its oral therapy and will also evaluate key endpoints in the non-study eye.