Dr Chon on Durvalumab Plus Chemotherapy and Olaparib in Endometrial Cancer

Hye Sook Chon, MD, gynecologic oncologist, Gynecologic Oncology Program, Moffitt Cancer Center, discusses updated findings from the phase 3 DUO-E trial (NCT04269200) of frontline durvalumab (Imfinzi) plus carboplatin and paclitaxel followed by durvalumab with or without olaparib (Lynparza) in patients with advanced or recurrent endometrial cancer.

DUO-E enrolled patients with newly diagnosed International Federation of Gynecology and Obstetrics 2009 stage III or IV or recurrent endometrial cancer. The primary end point of the DUO-E trial was progression-free survival (PFS); overall response rate (ORR) and duration of response (DOR) served as key secondary end points.

In the intent-to-treat population, the median PFS was 15.1 months (95% CI, 12.6-20.7) with durvalumab plus chemotherapy andolaparib (n = 239) compared with 10.2 months (95% CI, 9.7-14.7) in the durvalumab and chemotherapy arm (n = 238; HR, 0.78; 95% CI, 0.61-0.99) and 9.6 months (95% CI, 9.0-9.9) in the chemotherapy alone arm (n = 241; HR, 0.55; 95% CI, 0.43-0.69; P < .0001). The HR between the durvalumab plus chemotherapy arm and the chemotherapy alone arm was 0.71 (95% CI, 0.57-0.89; P = .003). The 18-month PFS rates with durvalumab plus chemotherapy and olaparib, durvalumab and chemotherapy, and chemotherapy alone were 46.3%, 37.8%, and 21.7%, respectively.

The ORR was 63.6% in the durvalumab/chemotherapy/olaparib arm, including a 16.3% complete response (CR) rate. The respective ORRs in the durvalumab plus chemotherapy and chemotherapy alone arms were 61.9%, including a 12.9% CR rate, and 55.1%, including a 9.6% CR rate. The odds ratio between the durvalumab and olaparib arm vs the chemotherapy alone arm was 1.44 (95% CI, 0.95-2.18); this value was 1.32 (95% CI, 0.89-1.98) between the durvalumab plus chemotherapy and chemotherapy alone arms.

The median DORs in the durvalumab/chemotherapy/olaparib, durvalumab/chemotherapy, and chemotherapy alone arms were 21.3 months (IQR, 8.1-29.9), 13.1 months (IQR, 6.0-NR), and 7.7 months (IQR, 5.1-13.5), respectively. At 24 months, 47.1%, 38.0%, and 14.8% of patients in these respective arms remained on treatment.