First report of successful pregnancies after treatment with alpelisib for PIK3CA-related overgrowth spectrum

Alpelisib is a selective PI3Kα inhibitor approved for treating PIK3CA-related overgrowth spectrum (PROS), a group of rare malformation disorders. Given that PI3Kα is a ubiquitous protein involved in cell proliferation, understanding the long-term impact of alpelisib on fertility is of critical importance. Here, we report the favorable outcomes of three pregnancies in PROS patients after prolonged treatment with alpelisib. Although disease progression was observed in all three patients during pregnancy, vascular malformations remained sensitive to alpelisib without evidence of secondary resistance upon resuming treatment. In conclusion, we provide the first evidence that alpelisib does not appear to affect fertility in female patients with PROS.