Exhibit 99.1
RAPT Therapeutics Announces Initiation of Phase 2b Trial of RPT193 in Patients with Moderate-to-Severe Atopic Dermatitis
SOUTH SAN FRANCISCO, Calif. – May 23, 2022 – RAPT Therapeutics, Inc. (Nasdaq: RAPT), a clinical-stage, immunology-based biopharmaceutical company focused on discovering, developing and commercializing oral small molecule therapies for patients with significant unmet needs in inflammatory diseases and oncology, today announced it has initiated its 16-week randomized, double-blind, placebo-controlled Phase 2b clinical trial to further evaluate the efficacy and safety of RPT193 as monotherapy in patients with moderate-to-severe atopic dermatitis (AD).
“We are excited to advance RPT193 into this Phase 2b trial in atopic dermatitis,” said Brian Wong, M.D., Ph.D., President and CEO of RAPT. “Our Phase 1b trial results support the potential of RPT193 as a safe, once-daily, oral treatment for AD that would be an attractive therapeutic alternative ahead of injectable drugs. Moreover, the clinical results were supported by our recently reported biomarker data. We are encouraged by the potential of RPT193 for patients with AD and other inflammatory diseases and we plan to expand development of RPT193 into a Phase 2a trial in asthma in the second half of this year.”
Last year, RAPT reported that in the Phase 1b trial, RPT193 demonstrated clear benefit over placebo in key exploratory efficacy measures at the end of the four-week treatment period (Day 29), including the Eczema Area and Severity Index (EASI) score, validated Investigator Global Assessment (vIGA), pruritis Numerical Rating Scale (NRS) and body surface area (BSA). By the end of the study, which included a two-week follow-up period (Day 43), RPT193 demonstrated improvement in EASI, EASI-50, EASI-75, EASI-90, vIGA and BSA. In a post-hoc statistical analysis comparing RPT193-treated patients to placebo-treated patients, the improvements in EASI, EASI-50 and BSA at Day 43 were statistically significant. RPT193 was well tolerated in the Phase 1b study. No serious adverse events were reported, and all adverse events reported were mild or moderate in intensity. In March 2022, biomarker data from the Phase 1b trial presented at the American Academy of Dermatology Annual Meeting demonstrated statistically significant improvements in the transcriptomic profile in the skin of RPT193-treated patients that correlated with key efficacy measures.
About the Phase 2b Trial of RPT193
The U.S. based Phase 2b trial is designed to assess the efficacy and safety of multiple-dose levels of RPT193 as monotherapy in patients with moderate-to-severe AD. The randomized, double-blind, placebo-controlled study will compare three oral dose levels of RPT193 (50, 200 and 400 mg once daily) to placebo with a treatment duration of 16 weeks. The co-primary endpoints for the trial are the percent change in the EASI from baseline at week 16 and incidence of treatment emergent adverse events. Key secondary endpoints include the percentage of patients achieving a vIGA score of 0 or 1 at week 16, the percentage of patients achieving EASI-75, defined as a 75% reduction in EASI from baseline to week 16, and the percent change from baseline in the Peak Pruritus Numerical Rating Scale (PP-NRS) from an itch daily e-diary at week 16. Furthermore, given maximum clinical benefit in the four-week Phase 1b trial was observed two weeks after cessation of treatment, patients in the Phase 2b trial will be followed for an additional eight weeks beyond the 16-week treatment period to understand whether sustained responses and/or further improvement in clinical parameters are observed beyond the treatment period.
