Phase II Study of Samotolisib in Children and Young Adults With Tumors Harboring Phosphoinositide 3-Kinase/Mammalian Target of Rapamycin Pathway Alterations: Pediatric MATCH APEC1621D

Laetsch TW, Ludwig K, Williams PM, Roy-Chowdhuri S, Patton DR, Coffey B, Reid JM, Piao J, Saguilig L, Alonzo TA, Berg SL, Mhlanga J, Fox E, Weigel BJ, Hawkins DS, Mooney MM, Takebe N, Tricoli JV, Janeway KA, Seibel NL, Parsons DW. Phase II Study of Samotolisib in Children and Young Adults With Tumors Harboring Phosphoinositide 3-Kinase/Mammalian Target of Rapamycin Pathway Alterations: Pediatric MATCH APEC1621D. JCO Precis Oncol. 2024 Sep;8:e2400258. doi: 10.1200/PO.24.00258. PMID: 39298693; PMCID: PMC11581706.

Patients aged 1–21 years with relapsed or refractory solid and CNS tumors were assigned to phase II studies of molecularly-targeted therapies on the NCI-COG Pediatric MATCH trial. Patients whose tumors harbored predefined genetic alterations in the Phosphoinositide 3-kinase (PI3k) / mammalian Target of Rapamycin (mTOR) pathway and lacked mitogen-activated protein kinase (MAPK) pathway activating alterations were treated with the PI3k/mTOR inhibitor samotolisib. Patients received samotolisib twice daily in 28-day cycles until disease progression or unacceptable toxicity. A rolling 6 limited dose escalation was performed as this was the first pediatric study of samotolisib. The primary end point was the objective response rate; secondary endpoints included progression free survival and the recommended phase 2 dose and toxicity of samotolisib in children.