A Phase 2 Study of Nab-sirolimus (ABI-009) in Patients With Advanced Malignant PEComa

This was a phase 2, single-arm, open-label, multi-center study to determine the efficacy and safety profile of nab-sirolimus in patients with advanced malignant PEComa. Patients were required to have measurable disease at baseline (per RECIST v1.1). Eligible patients received nab-sirolimus at 100 mg/m2 by IV infusion (over 30 minutes) weekly for 2 weeks followed by a week of rest (ie, on Day 1 and Day 8 in 21-day cycles). Patients remained on treatment until they experienced progressive disease or unacceptable toxicity, withdrew consent, or physician's decision. Patients who discontinued treatment entered the on-study Follow-up period for survival. Computed tomography or magnetic resonance imaging (MRI) scans were performed at screening, every 6 weeks for the first year, then every 12 weeks thereafter until the end of treatment. Throughout treatment with nab-sirolimus, patients were routinely assessed for toxicities, the need for dose modifications, and response assessments. The sample size was targeted to be \~30 patients in order to provide a reasonably precise estimate of the true ORR. Assuming an observed ORR of 30% and a sample size of 30, the lower bound of the 95% confidence interval (CI) for the estimated ORR would exclude values less than 14.7%. The primary analysis was predefined to be conducted when all patients have had the opportunity to be treated for at least 6 months. The study remained open for 3 additional years and the final analysis occured at study closure.