PIK3R1 E462_R465del

Reports 1 in LM

Position in PIK3R1 1 catalogued variant in this gene

Pathway and targeted therapy

Variant in the PI3K-AKT pathway. Repurposed drugs already used in the clinic for this pathway: alpelisib (PI3Kα inhibitor), sirolimus (mTOR inhibitor).

Open and recent trials (4 in vascular / lymphatic anomalies for alpelisib)

• A Trial of Targeted Therapies for Patients With Slow-Flow or Fast-Flow Vascular Malformations RECRUITING NCT05983159 · PHASE2 · WHO ICTRP
• 24VA022; VATCH Alpelisib for TIE2/PIK3CA Pathway VAs ACTIVE NOT RECRUITING NCT07543822 · PHASE2 · WHO ICTRP
• Alpelisib in Pediatric and Adult Patients With Lymphatic Malformations Associated With a PIK3CA Mutation. RECRUITING NCT05948943 · PHASE2, PHASE3 · WHO ICTRP
• A Study of Clinical Practice and Real-world Care of Patients Treated With mTOR, PI3K, and MEK Inhibitors for Extracranial Vascular Anomalies NOT YET RECRUITING NCT07767877 · WHO ICTRP

Primary sources 1

1. Molecular Characterization of Vascular Anomalies Tissues Guides Clinical Diagnosis.

   Henslee SB, Wooderchak-Donahue WL, Grimmer JF, Szankasi P, Bolia A, Frigerio A, Stevenson DA, Flores Daboub JA, Bayrak-Toydemir P. · Lymphat Res Biol · 2026