Imfinzi Combined with Chemotherapy Gains US Approval for Advanced or Recurrent Endometrial Cancer with Mismatch Repair Deficiency
Imfinzi, in combination with chemotherapy, has received approval in the United States for the treatment of adult patients with primary advanced or recurrent endometrial cancer that is mismatch repair deficient (dMMR). This decision was influenced by the DUO-E trial results, which demonstrated that Imfinzi significantly reduced the risk of disease progression or death by 58% compared to chemotherapy alone.
The Food and Drug Administration (FDA) approved this treatment based on a detailed analysis of the DUO-E Phase III trial, which was specifically focused on the mismatch repair status. The findings from this trial were also published in the Journal of Clinical Oncology.
In the DUO-E trial, patients receiving Imfinzi along with carboplatin and paclitaxel, followed by Imfinzi as a monotherapy, showed a 58% reduction in the risk of disease progression or death compared to those receiving only chemotherapy. The hazard ratio was 0.42, with a 95% confidence interval of 0.22-0.80.
Endometrial cancer is the fourth most common cancer among women in the US, with over 66,000 diagnoses and nearly 12,000 deaths reported in 2022. Early-stage diagnosis offers a five-year survival rate of about 80-90%, but advanced stages have significantly lower survival rates, falling below 20%.
Overview of the DUO-E Trial
The DUO-E trial is a large, randomised, double-blind, placebo-controlled, multicentre Phase III study. It investigated first-line treatment with Imfinzi plus carboplatin and paclitaxel, followed by maintenance therapy with either Imfinzi alone or Imfinzi plus Lynparza, compared to standard platinum-based chemotherapy. The trial included 699 patients with newly diagnosed advanced or recurrent epithelial endometrial carcinoma.
Participants were randomly assigned to receive either Imfinzi (1120mg) or a placebo, administered every three weeks alongside standard chemotherapy. After 4-6 cycles of chemotherapy, patients who had not progressed received either Imfinzi (1500mg) or a placebo every four weeks as maintenance therapy. Additionally, they received Lynparza (300mg twice daily) or a placebo until disease progression.
The primary endpoint was progression-free survival (PFS) compared to standard care. Secondary endpoints included overall survival (OS), safety, and tolerability. The trial continues to assess OS for both maintenance therapies with Imfinzi.
Understanding Endometrial Cancer
Endometrial cancer arises from the lining of the uterus and is most common in postmenopausal women, with the average age at diagnosis being over 60. Globally, it is the sixth most common cancer in women. Incidence and mortality rates are expected to rise significantly by 2050.
Most endometrial cancer cases are diagnosed early, with the cancer confined to the uterus, and treated with surgery and/or radiation, resulting in high five-year survival rates (approximately 80-90%). However, advanced stages (Stage III-IV) have much lower survival rates, below 20%. Immunotherapy combined with chemotherapy is emerging as a new standard for advanced endometrial cancer, particularly for the 20-30% of patients with dMMR disease. However, there remains a significant need for effective treatments for the remaining 70-80% of patients with proficient mismatch repair (pMMR) disease.
Comentários