Olaparib doubled pression-free survival for women with advanced ovarian cancer

Session: Maintenance olaparib for patients with newly diagnosed advanced ovarian cancer and a BRCA mutation: 5-year follow-up from SOLO1

Speaker: William Bradley, gynecologic oncologist, Froedert and Medical College of Wisconsin, Milwaukee, WI

Olaparib earns high marks as a standard of care for women with newly diagnosed advanced ovarian cancer and a BRCA1/2 mutation

A recent, first-of-its-kind, 5-year follow-up trial to the pivotal, 2018 SOLO-1 study determined that maintenance treatment with olaparib for women with advanced ovarian cancer and a BRCA1/2 mutation led to a doubling in progression-free survival. This was a consistent and sustained progression-free survival benefit across both higher risk and lower risk patient groups. No new safety signals were identified during this follow up period.

William H. Bradley, MD, presented these findings during SGO 2021’s Scientific Plenary III: Seminal Abstract Session: Taking a Deeper Dive into Practice-Changing Trials.

When all was said, done, and analyzed, Dr. Bradley concluded that the results demonstrated that olaparib should be considered a standard of care for patients with advanced ovarian cancer and a BRCA1/2 somatic or germline mutation—a mutation present in about one-fourth of ovarian cancer diagnoses.

“Even years after patients completed the planned two years of olaparib treatment, their progression-free survival benefit endured,” Dr. Bradley emphasized. And although gynecologic oncologists use the “cure word” with great caution, Dr. Bradley went on to say, “These results further support the use of maintenance olaparib as a standard of care for women with newly diagnosed advanced ovarian cancer and a BRCA1/2 mutation that suggests the possibility of long term remission—or even cure for some patients.”

The Backstory

SOLO-1 evaluated olaparib, an oral inhibitor of poly [ADP-ribose] polymerase (PARP) as a 2-year maintenance therapy in 391 women with newly diagnosed ovarian cancer and a BRCA1/2 mutation. The 391 women in the study had all undergone platinum-based chemotherapy as their initial treatment and were then researchers randomly assigned 260 women to receive olaparib and 131 to get a placebo for two years or until the cancer worsened.

The follow-up study looked at five years’ worth of data that came after SOLO-1, with the new results representing the longest follow up for any PARP inhibitor trial and the first database to follow up beyond the end of PARP inhibitor maintenance monotherapy, Dr. Bradley pointed out. 

In the follow-up analysis, median progression-free survival for the overall SOLO-1 population was sustained far beyond the end of treatment:

  • More than twice as many women who received olaparib as part of SOLO-1 were still alive five years later, with no progression of their cancer.
  • There was a median progression-free survival of 56.0 months with olaparib vs. 13.8 months with placebo
  • Data identified a 5-year progression-free survival for 48 percent with olaparib vs. 21percent with placebo.
  • Olaparib recipients had better five-year progression-free survival regardless of initial progression risk.

Calling the follow-up study results “profound,” the study’s discussant, Deborah Armstrong, MD, Professor of Oncology and Director of the Breast and Ovarian Surveillance Service at Johns Hopkins Medicine, echoed Dr. Bradley’s optimism. She added that the results may be “telling us that getting PARP inhibitors earlier on may be important.”