Maintenance olaparib for patients with newly diagnosed, advanced ovarian cancer and a BRCA mutation: 5-year follow-up from SOLO1
For advanced ovarian cancer, olaparib as maintenance drug reduces disease progression, five-year follow-up data show
CHICAGO (March 20, 2021)—In women with advanced ovarian cancer, olaparib used as maintenance therapy for two years after primary treatment significantly lengthens five-year progression-free survival, being alive with no recurrence of the cancer, a new study finds. The study results will be presented at the Society of Gynecologic Oncology 2021 Virtual Annual Meeting on Women’s Cancer.
“Even years after patients completed the planned two years of olaparib treatment, their progression-free survival benefit endured,” said the study’s lead author, William Bradley, MD, a gynecologic oncologist at Froedert and Medical College of Wisconsin, Milwaukee. “That’s very good news.”
Olaparib is an oral targeted chemotherapy drug known as a PARP inhibitor. It stops the cell’s PARP enzyme from repairing DNA damage, important in cancer progression.
This study evaluated five years of follow-up data from a prior study, which Dr. Bradley called “the longest follow-up for any PARP inhibitor in the setting of maintenance therapy after primary therapy.”
The aim of maintenance therapy is to slow the cancer’s growth after initial treatment, usually with platin-based chemotherapy and surgical treatment.
Olaparib was studied in patients with a mutation, or harmful alteration, of the BRCA1 and/or BRCA2 genes, Dr. Bradley said. This mutation is present in about one-fourth of women with ovarian cancer.
The study data came from the SOLO-1 clinical trial, initially published in 2018. That study included 391 patients with a BRCA mutation and newly diagnosed advanced ovarian cancer who first completed platin-based chemotherapy. The SOLO-1 trial randomly assigned 260 women to receive olaparib and 131 to get a dummy drug (placebo) for two years or until the cancer worsened.
The current analysis found that more than twice as many women who received olaparib were still alive five years after the beginning of the study with no progression of their cancer. More than 48 percent of olaparib recipients had five-year progression-free survival versus only 20.5 percent of placebo recipients, the researchers reported.
Additionally, the researchers analyzed subgroups of patients depending on their risk of disease progression. Compared with placebo, olaparib recipients had better five-year progression-free survival regardless of their initial progression risk.
“Olaparib maintenance therapy should be a standard of care for women with a BRCA mutation and advanced ovarian cancer,” Dr. Bradley said.
Although they observed no new safety warnings, potential side effects of olaparib include blood abnormalities. He said patients taking olaparib should receive routine physical assessments and lab tests under an oncologist’s care.