Abstract Background Chemotherapy-induced alopecia (CIA) is one of the most distressing side effects experienced by breast cancer patients undergoing adjuvant chemotherapy. In some cases, hair loss is incomplete or permanent (permanent CIA), significantly impairing quality of life, psychological well-being, and social reintegration. Although scalp cooling systems such as PAXMAN have shown effectiveness in reducing CIA, complete hair preservation is not achieved in all patients, and cases of permanent CIA still occur.HairRepro MEDI α is a novel scalp lotion containing a newly developed α-lipoic acid derivative, DHLH (histidine dithioloctamide with Na/Zn), which has been shown in preclinical studies to reduce inflammatory infiltration in the scalp induced by cytotoxic agents. A prior multi-institutional trial in Japan suggested its potential benefit in promoting hair regrowth among CIA-affected patients.This study is the first exploratory clinical trial in Japan to evaluate the combined use of the PAXMAN cooling system and HairRepro MEDI α, with the aim of improving not only CIA prevention but also post-chemotherapy hair regrowth and overall patient satisfaction. Methods This retrospective exploratory study enrolled 22 breast cancer patients receiving adjuvant chemotherapy at our institution between 2022 and 2024. Chemotherapy regimens included HP+DTX→ddAC (n=8), HP+DTX (n=4), TC (n=2), ddAC→ddPTX (n=6), and others (n=2). HairRepro MEDI α was applied topically to the scalp and eyebrows at a dose of 4 mL twice daily, starting 6 days prior to the initiation of chemotherapy and continuing until day 90 post-final chemotherapy. PAXMAN scalp cooling was performed during each chemotherapy cycle. Photographs were taken at baseline (day −6), prior to each chemotherapy course, and on days 30, 60, and 90 after the final chemotherapy to assess hair loss percentage. Adverse events were recorded throughout. Results Among the 22 patients, the median hair loss at the final chemotherapy session was 45%, with 11 patients (50%) exhibiting Grade 1 or lower alopecia, indicating successful prevention. No adverse events related to the use of HairRepro MEDI α were observed.Hair loss typically began 4 to 6 weeks after the first chemotherapy dose. Compared to historical data from PAXMAN-only users, the onset of alopecia appeared delayed. Notably, all patients showed full scalp hair regrowth by 3 months post-chemotherapy, with hair loss scores returning to 0%, suggesting effective recovery.These findings indicate a potentially additive benefit of HairRepro MEDI α in both prevention and recovery from CIA when used alongside scalp cooling. Conclusion The combination of PAXMAN and HairRepro MEDI α achieved favorable outcomes in the prevention and recovery of CIA among Japanese breast cancer patients receiving adjuvant chemotherapy. A 50% success rate for Grade ≤1 alopecia, along with complete hair regrowth by 3 months, suggests enhanced efficacy compared to previous studies involving scalp cooling alone. Notably, this is the first clinical report from Japan to evaluate this combination therapy, providing new insights into supportive care strategies tailored for Asian populations. Further randomized trials are warranted to confirm these preliminary findings and refine CIA management protocols. Citation Format: E. Kanaya, K. Matsui, A. Urasaki, M. Furukawa, S. Nagasawa, M. Araki, K. Sukegawa, S. Sekine, T. Fujii. Exploratory Study on the Efficacy and Safety of Combined Scalp Cooling and HairRepro MEDIα for Chemotherapy-Induced Alopecia in Japanese Breast Cancer Patients abstract. In: Proceedings of the San Antonio Breast Cancer Symposium 2025; 2025 Dec 9-12; San Antonio, TX. Philadelphia (PA): AACR; Clin Cancer Res 2026;32(4 Suppl):Abstract nr PS1-01-19.
Kanaya et al. (Tue,) studied this question.