Rakuten Medical Presents Long-Term Results for ASP-1929 Photoimmunotherapy
News related to:Rakuten Medical, Inc · 2 min read
SAN DIEGO, Oct. 23, 2026 /CourierPR/ -- Rakuten Medical, a global biotechnology company, has presented long-term follow-up results from its Phase 1b/2 ASP-1929-181 study at the European Society for Medical Oncology (ESMO) Congress 2026 in Madrid, Spain. The study evaluated the combination of ASP-1929 photoimmunotherapy with pembrolizumab in patients with recurrent and/or metastatic head and neck squamous cell carcinoma (r/m HNSCC).
The median duration of response (DOR) was 44.3 months, supporting the durability of the response. The overall survival (OS) rate was 35.3% at 48 months, and the median OS was 28.2 months, suggesting meaningful long-term survival. Among the five patients who achieved a complete response (CR), four remained alive with follow-up ranging from more than 42 months to more than 60 months.
The current analysis extended the follow-up by an additional 21.4 months, bringing the median follow-up to 53.1 months. The study included 17 efficacy-evaluable patients out of the 19 enrolled in the ASP-1929-181 study. The data cutoff for the analysis was February 10, 2026.
The findings from the ASP-1929-181 study showed durable clinical activity and a manageable safety profile after a median follow-up of 31.7 months. The exploratory subgroup analyses by HPV status, PD-L1 CPS expression, and tumor size at baseline showed generally consistent efficacy and safety outcomes. No new safety signals were observed.
Rakuten Medical is currently conducting the global Phase 3 ASP-1929-381 study (NCT06699212), evaluating ASP-1929 photoimmunotherapy in combination with pembrolizumab as a first-line treatment for locoregional recurrent HNSCC. The company aims to submit a Biologics License Application (BLA) for ASP-1929 to the U.S. FDA in 2028.
The Alluminox® platform, on which ASP-1929 is based, combines pharmaceuticals, medical devices, and medical technology. The photoimmunotherapy involves the administration of a drug component, which includes an antibody-dye conjugate, and the activation of the drug with a light source. This activation leads to the selective necrosis of targeted cells and may also result in local and systemic immune activation.
The study was presented as an e-poster on October 23, 2026, at 8:00 a.m. (CET) at the ESMO Congress 2026. The findings are exploratory and should be interpreted in light of the study's limitations, including the small sample size and limited patient numbers in some subgroup analyses.