Phosphatidylinositol 3-kinase inhibitors (PI3Ki) are a class of drugs used to treat a specific type of breast cancer, known as hormone receptor-positive (HR+), human epidermal growth factor receptor 2-negative (HER2-), PIK3CA-mutated advanced breast cancer. However, some PI3Kis have been given US Food and Drug Administration (FDA) accelerated approval for the treatment of relapsed or refractory (R/R) non-Hodgkin lymphoma (NHL).
As part of the FDA accelerated approval process, pharmaceutical companies must complete post-approval confirmatory studies to show that the drug is achieving the results for which it is indicated. If these studies are not completed, the FDA accelerated approval could be revoked.
In a poster presented at the 48th Annual Oncology Nursing Society Congress in San Antonio, Texas, Natasha Kormanik MSN, CRNP, FNP-BC, OCN, of the FDA presented a synthesis of the 4 PI3Kis given FDA accelerated approval for R/R NHL and their toxicity profiles. The drugs, idelalisib, copanlisib, duvelisib, and umbralisib, have all been partially or fully withdrawn from market due to safety concerns.
Historically, FDA accelerated approval was granted for drugs that had good overall response rates in single-arm trials, but based on the toxicity profiles of PI3Kis, the FDA is now moving to a randomized data requirement for approval. Additionally, confirmatory studies are now required to be ongoing at the time of application for FDA accelerated approval. The changes come after a vote by an FDA-assembled, class-wide Oncologic Drug Advisory Committee, held April 21, 2022, to discuss the safety and approach for future approvals of PI3Kis.
“Oncology nurses, especially those directly involved in clinical trials, are well positioned to improve future drug development in this space and should be familiar with the current regulatory landscape,” Kormanik stated in her poster.
While overall response rates will still be considered, it is important to ensure that the drugs are safe in the long term for patients who receive them. As nurses are often the first to note adverse events, it is important that they are aware and communicate to the entire care team any concerns about toxicity.
Kormanik N, Wall L, Felluca D, et al. FDA Accelerated Approval: Oncology Nurse Implications with PI3K Inhibitors. Abstract #P351. Presented at the 48th Annual ONS Congress; San Antonio, TX, April 26-30, 2023.