On November 22, 2021, the Food and Drug Administration approved sirolimus protein-bound particles for injectable suspension (albumin-bound) for adult patients with locally advanced unresectable or metastatic malignant perivascular epithelioid cell tumour (PEComa). 

Efficacy was evaluated in AMPECT (NCT02494570), a multicenter, single-arm clinical trial in 31 patients with locally advanced unresectable or metastatic malignant PEComa. Patients received sirolimus protein-bound particles at 100 mg/m2 on days 1 and 8 of each 21-day cycle until disease progression or unacceptable toxicity. 

The main efficacy outcome measures were overall response rate (ORR) and duration of response (DOR), as assessed by blinded independent central review, using RECIST v.1.1. ORR was 39% (95% CI: 22%, 58%), including 2 patients with complete responses. Median DOR was not reached (95% CI: 6.5 months, not estimable). Among responders, 67% had a response lasting greater than 12 months and 58% had a response lasting greater than 24 months.  

The most common (≥30%) adverse reactions were stomatitis, fatigue, rash, infection, nausea, oedema, diarrhoea, musculoskeletal pain, decreased weight, decreased appetite, cough, vomiting, and dysgeusia. The most common (≥6%) grade 3 to 4 laboratory abnormalities were decreased lymphocytes, increased glucose, decreased potassium, decreased phosphate, decreased haemoglobin, and increased lipase.  

The recommended dosage is 100 mg/m2 administered as an IV infusion over 30 minutes on days 1 and 8 of each 21-day cycle until disease progression or unacceptable toxicity. 

View full prescribing information for sirolimus protein-bound particles here.

Source: FDA