M132101

M132101 is an investigational topical small molecule being developed by Maruho Co., Ltd. for the treatment of infantile hemangioma (IH). Infantile hemangiomas are common benign vascular tumors of infancy that typically undergo a period of rapid growth followed by slow involution. While oral propranolol is the current gold standard for systemic treatment, topical therapies are preferred for superficial or localized lesions to avoid systemic side effects such as bradycardia and hypoglycemia. M132101 is currently in Phase 1 clinical development in Japan, where it is being evaluated for safety, tolerability, and pharmacokinetics in healthy adult volunteers. Although its specific chemical structure has not been widely disclosed, it is categorized within the class of beta-adrenergic receptor antagonists, which are known to promote hemangioma involution through vasoconstriction, inhibition of pro-angiogenic factors (e.g., VEGF, bFGF), and the induction of apoptosis in endothelial cells.