FDA OKs Treatment for HER2-Negative Breast Cancer with Germline BRCA Mutation

Officials with the FDA have approved talazoparib (Talzenna, Pfizer) for the treatment of HER2-negative locally advanced or metastatic breast cancer with germline BRCA (gBRCA) mutations, according to a press release.

Talazoparib, a poly ADP-ribose polymerase (PARP) inhibitor, is indicated for patients with known deleterious or suspected deleterious gBRCA-mutated breast cancer who are selected for the therapy based on an FDA-approved companion diagnostic.

As a dual-mechanism PARP inhibitor, talazoparib both inhibits and traps the PARP enzyme, which may lead to heightened cell death, according to Pfizer.

The approval was based on clinical data from the EMBRACA trial, which included 431 participants with a known deleterious or suspected deleterious gBRCA mutation who have received no more than 3 prior cytotoxic chemotherapy regimens for locally advanced or metastatic disease. Additionally, patients were required to have received treatment with an anthracycline and/or a taxane (unless contraindicated) in the neoadjuvant, adjuvant, and/or metastatic treatment setting.

Overall, the trial met its primary endpoint, with an estimated median progression-free survival of 8.6 and 5.6 months in the talazoparib and chemotherapy arms, respectively (HR 0.54; 95% CI: 0.41, 0.71; p<0.0001).

The most commonly reported adverse reactions were fatigue, anemia, nausea, neutropenia, headache, thrombocytopenia, vomiting, alopecia, diarrhea, and decreased appetite, according to Pfizer.

In addition, the FDA also granted approval to the BRACAnalysis CDx test (Myriad Genetic Laboratories), a companion diagnostic test to identify patients who are eligible for treatment with talazoparib. The approval was based on the efficacy of the test demonstrated in the EMBRACA trial population.

According to the release, the recommended talazoparib dose is 1 mg taken as a single oral daily dose, with or without food. The prescribing information for the drug includes warnings and precautions for myelodysplastic syndrome/acute myeloid leukemia, myelosuppression, and embryo-fetal toxicity.

References

FDA approves talazoparib for gBRCAm HER2-negative locally advanced or metastatic breast cancer [news release]. FDA’s website. https://bit.ly/2COKoeD. Accessed October 16, 2018.

Talazoparib Fact Sheet. Pfizer’s website. https://www.pfizer.com/files/news/asco/Talazoparib_Fact_Sheet.pdf. Accessed October 16, 2018.