FDA Approves Atezolizumab, Hyaluronidase-tqjs Subcutaneous Injection for HCC

The United States Food and Drug Administration (FDA) has granted approval for atezolizumab and hyaluronidase-tqjs (Tecentriq Hybreza, Genentech) for subcutaneous injection in adult patients with hepatocellular carcinoma (HCC).

The atezolizumab and hyaluronidase-tqjs subcutaneous combination was also approved for non-small cell lung cancer, small cell lung cancer, melanoma, and alveolar soft part sarcoma.

FDA approval comes after the results of the IMscin001 trial, an open-label, multi-center, international analysis of adult patients who were not previously treated with immunotherapy and who had not experienced disease progression following treatment with platinum-based chemotherapy. In the trial, a total of 371 patients were randomized (2:1) to receive subcutaneous atezolizumab and hyaluronidase-tqjs or intravenous atezolizumab until disease progression or unacceptable toxicity.

The primary outcome measure of IMscin001 was atezolizumab exposure. The co-primary pharmacokinetic endpoints were Cycle 1 _Ctrough and AUC_0-21days. Additional efficacy outcome measures included overall response rate (ORR), progression-free survival (PFS), and overall survival (OS).

The geometric mean ratio (90% CI) of subcutaneous atezolizumab and intravenous atezolizumab for Cycle 1 _Ctrough was 1.05 and 0.87 for AUC_0-21days. These met the lower limit of the geometric mean ratio (90% CI) above the pre-specified threshold of 0.80 for comparability.

No notable differences were reported between the different formulations with regard to ORR, PFS, or OS; the confirmed ORR was 9% in the subcutaneous atezolizumab and hyaluronidase-tqjs arm and 8% in the intravenous atezolizumab arm.

Common adverse events of any grade included fatigue, musculoskeletal pain, cough, dyspnea, and decreased appetite.

The FDA noted that the recommended dosage is a single subcutaneous injection (15 mL containing 1,875 mg of atezolizumab and 30,000 units of hyaluronidase) administered in the thigh over a 7-minute span every 3 weeks.