Ovarian cancer remains elusive and deadly. More than two out of every three women who are diagnosed with cancer of the ovaries is in an advanced stage of the disease. And among those, more than half will die within five years.
But help may be on the way for one subset of those with the disease. On Wednesday, AstraZeneca touted promising results of a phase 3 trial in patients with newly diagnosed ovarian cancer who have advanced disease but no BRCA mutations.
An interim analysis of the DUO-O study showed that a combination of AZ and Merck’s Lynparza and AZ's Imfinzi—added to chemotherapy and bevacizumab—significantly improved progression-free survival (PFS) compared to patients from the control arm, who were given chemotherapy and bevacizumab.
AZ didn’t provide numbers but called the interim results “statistically significant and clinically meaningful” in PFS. The company added that data on overall survival (OS) and other secondary endpoints are “immature” and will be assessed in subsequent analyses.
AstraZeneca is partnered on Lynparza with Merck in a 2017 deal worth up to $8.5 billion.
In the DUO-O trial, the regimen that performed best in PFS was initial treatment with a combination of Imfinzi, bevacizumab and chemotherapy, followed by maintenance with bevacizumab, Lynparza and Imfinzi. Bevacizumab is the generic name for Roche's Avastin.
In an additional arm, Imfinzi, bevacizumab and chemotherapy were provided for initial treatment followed by maintenance with Imfinzi, bevacizumab and placebo. This regimen showed a numerical improvement in PFS versus the control arm but did not reach statistical significance.
The control arm patients received chemotherapy plus bevacizumab and placebo in the induction phase, followed by bevacizumab and placebo in maintenance.
Susan Galbraith, AZ’s oncology R&D chief, said in a release that ultimately subgroup data analysis and understanding key secondary endpoints will be important in assessing the overall viability of the Imfinzi/Lynparza combo.
“While there has been significant progress for patients with advanced ovarian cancer, an unmet need still remains,” Galbraith added.
The safety and tolerability of the tested combinations were in line with previous clinical trials. This was a key footnote as PARP inhibitors, such as Lynparza, have come under increased scrutiny over their safety in treating patients with ovarian cancer.
Last year, AZ and Merck voluntarily pulled Lynparza’s approval in fourth-line BRCA-mutated advanced ovarian cancer patients because of concerns that it could increase the risk of death. The FDA agreed to the move, voiding AZ’s first approval for Lynparza in 2014.
After its first endorsement, Lynparza gained initial approvals in breast (2018), pancreatic (2019) and prostate cancer (2020).
Imfinzi was initially approved in 2017 for bladder cancer, followed by nods in lung cancer (2020), biliary tract cancer (2022) and unresectable hepatocellular carcinoma (2022).
AZ reported sales of $2.8 billion for Imfinzi last year, which was a 15% increase from the previous year, and $2.6 billion for Lynparza, which was a 12% increase from 2021. Merck reported $1.12 billion in Lynparza sales in 2022.