Targeted Therapies in Infantile Hemangiomas and Vascular Malformations: From β-Blockers to PI3K/AKT/mTOR Inhibitors

Vascular tumours and malformations encompass infantile hemangiomas (IHs) and genetically driven vascular malformations with distinct natural histories and therapeutic vulnerabilities. The discovery that the non-selective beta-blocker propranolol induces rapid regression of proliferating IHs established the first widely adopted systemic pharmacologic therapy in vascular anomaly care and provided a clinical proof-of-concept that targeting lesion-specific endothelial biology can alter disease course. In parallel, recurrent somatic variants affecting PI3K/AKT/mTOR (e.g., PIK3CA, TEK/TIE2, AKT1) and RAS/MAPK (e.g., KRAS, NRAS) signalling have reframed many malformations as mosaic disorders amenable to targeted inhibition with agents such as sirolimus, alpelisib, AKT inhibitors and MEK inhibitors. This review synthesizes translational mechanisms, clinical evidence and safety considerations for beta-blockers and emerging targeted therapies, emphasizing lesion phenotype, timing of intervention and molecular stratification as determinants of response. We highlight current limitations, including toxicity, durability and pathway escape, and outline future directions for precision therapy and genotype-guided trial design in vascular anomalies.