Fixed-Dose Pertuzumab-Based Regimen Under Study in FeDeriCa Trial
Posted: Thursday, April 22, 2021
Antoinette R. Tan, MD, of Levine Cancer Institute, Atrium Health, Charlotte, North Carolina and colleagues demonstrated comparable pathologic complete response rate, pharmacokinetics, and safety with a fixed-dose, subcutaneous formulation of pertuzumab, trastuzumab, and hyaluronidase-zzxf versus intravenous pertuzumab plus trastuzumab. Their work, which centered on patients with HER2-positive early-stage breast cancer in the neoadjuvant-adjuvant setting, was published in The Lancet Oncology.
The phase III randomized open-label FeDeriCa trial included 500 patients with HER2-positive stage II to IIIC breast cancer and a left ventricular ejection fraction of at least 55%. Individuals were stratified depending on hormone receptor status, clinical stage, and chemotherapy regimen. They were randomly assigned (1:1) to receive either the intravenous regimen of pertuzumab plus trastuzumab or the fixed-dose subcutaneous combination regimen. Both treatments were given every 3 weeks after neoadjuvant chemotherapy.
Notably, the primary study objective was met. The researchers found the fixed-dose combination for subcutaneous injection provided noninferior cycle 7 pertuzumab serum C trough concentrations compared with the intravenous combination. The geometric mean ratio of pertuzumab serum C trough subcutaneous to serum C trough intravenous was 1.22 (90% confidence interval [CI] = 1–1.31). Pathologic complete response was similar between the two treatments and was achieved in 148 patients in the subcutaneous group (59.7%; 95% CI = 53.3%–65.8%) and 150 patients in the intravenous group (59.5%; 95% CI = 53.3%–65.8%).
Grade 3 or 4 adverse events most commonly included neutropenia, decreased neutrophil count, febrile neutropenia, diarrhea, and decreased white blood cell count. A total of 10% of patients in each group experienced serious adverse events related to treatment. The investigators noted that follow-up will continue to track long-term safety and efficacy.
Disclosure: For full disclosures of study authors, visit thelancet.com.