Frequency Therapeutics, Inc. announced that it has completed enrollment of its placebo-controlled Phase 2b study of FX-322 in adults with acquired sensorineural hearing loss (SNHL). The FX-322-208 study, which enrolled 142 individuals, is designed to show improvement in a pre-specified measure of speech perception. The Company plans to release study data in the first quarter of 2023.

FX-322-208 is a prospective, randomized, double-blinded, placebo-controlled, multi-center Phase 2b study designed to evaluate the efficacy of a single administration of FX-322 on speech perception in subjects aged 18-65 with hearing loss associated with either noise-induced or permanent idiopathic sudden SNHL. The study enrolled 142 participants, exceeding the original enrollment target of approximately 124, and is being conducted at 28 clinical sites across the US. The Company previously aligned with the US Food and Drug Administration (FDA) on the use of the specific speech perception primary endpoint.

With improved speech perception, individuals may hear words more clearly, a critical unmet need for individuals with hearing loss. The FX-322-208 study is powered at 80% (significance level of 0.05) to observe a statistically significant and clinically meaningful improvement in speech perception at day 90 following dosing, with study responders defined as individuals exceeding the upper 95% confidence interval in the speech perception test. The Company has not publicly disclosed the specific test used for the primary endpoint to maximize the rigor of the studyand mitigate potential bias.

During the study, subjects participate in a range of audiologic exams, including pure-tone audiometry, word recognition in quiet, word recognition in noise, the Tinnitus Functional Index (TFI), as well as multiple patient- reported outcome measures including Frequency's proprietary patient reported outcome instrument (RADIAL) in acquired SNHL. All subjects are required to have a documented audiogram from at least six months prior to screening and most patients are evaluated over a 270-day period following dosing. The study's rigorous design includes a lead-in phase with multiple baseline measures.

Subjects with instability of baseline tests are disqualified from participation in the study. Study audiometry testing sessions are recorded and monitored by third party audiologists to ensure consistency and identify any anomalies related to how tests were conducted. In prior studies, the Company observed the greatest concentration of speech perception improvements in individuals with permanent sudden or noise-induced sensorineural hearing loss in the moderate to lower severe hearing loss range.

These learnings informed the design and inclusion criteria for the FX-322-208 study. More than 200 individuals have been dosed with a single injection of FX-322 in prior or ongoing studies, and the drug candidate has continued to exhibit a favorable safety profile with no drug-related serious adverse events.