The US Food and Drug Administration (FDA) has granted approval to AstraZeneca's immune checkpoint inhibitor Imfinzi (durvalumab) in combination with chemotherapy for the treatment of DNA mismatch repair (MMR) deficient endometrial cancer. This decision follows positive outcomes from the Phase III DUO-E clinical trial involving 805 patients with advanced or recurrent endometrial cancer. While eligibility for the trial did not hinge on MMR status, patients required MMR immunohistochemistry testing data.
The approved regimen involves administering the PD-1 checkpoint inhibitor alongside carboplatin and paclitaxel chemotherapy, followed by maintenance therapy with Imfinzi alone. Results demonstrated significant benefits in progression-free survival, particularly in patients with dMMR tumors. For those receiving Imfinzi plus chemotherapy followed by Imfinzi alone, median progression-free survival was not yet reached, compared to 7 months for those on chemotherapy and placebo.
Imfinzi, already approved for several other cancers including certain types of lung, biliary tract, and liver cancers, now marks its first biomarker-specific indication with this dMMR endometrial cancer approval. This milestone underscores its efficacy in targeting specific genetic profiles, reflecting a significant advancement in personalized oncology treatment strategies. The FDA's decision highlights Imfinzi's growing role in expanding treatment options and improving outcomes for patients with specific biomarker-defined cancers.