People with newly diagnosed advanced ovarian cancer without BRCA mutations, who received durvalumab (Imfinzi) and olaparib (Lynparza) in addition to the standard of care had improved progression-free survival compared with those who received the standard of care only, according to the interim analysis of DUO-O, an international phase III randomised clinical trial.

The research was presented at the 2023 American Society of Clinical Oncology (ASCO) Annual Meeting.

In the trial, newly diagnosed patients with advanced high-grade epithelial ovarian cancer without BRCA mutations who received the standard of care (upfront paclitaxel/carboplatin and bevacizumab, plus maintenance bevacizumab) plus upfront durvalumab and maintenance durvalumab and olaparib had improvement in PFS compared to patients who received the standard of care.

Of patients with HRD-positive tumours in the durvalumab + olaparib group, the risk of the disease progressing was 51% less than for those who received the standard-of-care.

In addition, for patients in the intent-to-treat group who received durvalumab + olaparib, the risk of the disease progressing was 37% less than for those who received the standard of care.

In the durvalumab + olaparib arm, the risk of the disease progressing was 32% lower in all subsets of patients, including both HRD-positive and negative patients, compared to the standard-of-care arm.

“While there has been significant progress for patients with advanced ovarian cancer, an unmet need still remains. Our trial results provide encouraging evidence that we can find new treatment approaches for patients with advanced disease,” said Philipp Harter, MD, PhD, director in the Department of Gynecology and Gynecologic Oncology at the Evangelische Kliniken Essen-Mitte hospital in Essen, Germany.

An estimated 19,710 new cases of ovarian cancer will be diagnosed in the United States in 2023, and an estimated 13,270 deaths due to the disease will occur.  

Only 20% of all cases of ovarian cancer are found early.

When disease is detected at stage III or higher, survival rates can be as low as 30%.

About half of the patients who are diagnosed with ovarian cancer are 63 years or older, and it is more common in White people than in Black people.¹

The current standard of care includes chemotherapy (paclitaxel/carboplatin) and bevacizumab, an antiangiogenic agent. Durvalumab is a checkpoint inhibitor and olaparib is a PARP inhibitor, which blocks a certain cell-repair mechanism.

Two recent studies have shown that maintenance olaparib benefits newly diagnosed patients with a BRCA mutation and that bevacizumab benefits patients with HRD-positive tumours.

In patients with tumours that are HRD-positive, cancer cells have a harder time repairing themselves which means certain treatments, such as PARP inhibitors, are more likely to be effective.

This led researchers to explore the novel combination of bevacizumab and durvalumab with the addition of olaparib to the maintenance therapy regimen to see if it would enhance the antitumor effect.

Researchers will formally assess overall survival and other secondary endpoints in a subsequent analysis.  

References

1. "Ovarian, Fallopian Tube, and Peritoneal Cancer: Statistics"

Source: ASCO