FRIDAY, June 4, 2021 (HealthDay News) — The twice-daily pill may dramatically reduce the risk of breast cancer recurrence in women who are genetically predisposed to the disease, researchers report.
The pill – Olaparib (Linparza) – works by blocking a natural enzyme called PARP that normally repairs DNA damage in healthy cells, but actually promotes the growth of cancer cells in these women.
Lead researcher Dr Andrew Tut from the Breast Cancer Now Toby Robbins Research Center said early high-risk breast cancer patients taking olaparib for one year had a 42% lower risk of cancer recurrence or death. Cancer Research Institute in London.
“Patients who received olaparib after surgery and chemotherapy were more likely to survive without cancer and survive metastasis than patients who received placebo,” he said.
These results were presented Thursday at an online meeting of the American Society of Clinical Oncology. Findings presented at meetings should be considered preliminary until published in a peer-reviewed journal.
Olaparib is already approved for the treatment of patients with metastatic breast cancer who have mutations in either the BRCA1 or BRCA2 genes. These genes usually suppress cancer, but the mutations actually increase the risk of cancer for some people.
About 5% of breast cancers are associated with BRCA1 or BRCA2 mutations, Tut noted.
Breast cancers caused by BRCA1 or BRCA2 mutations depend on the PARP enzyme to survive, grow and divide. Medicines called PARP inhibitors take advantage of this fact to block the enzyme and prevent the cancer from coming back.
In this clinical trial, more than 1,800 patients with stage 2 to 3 breast cancer treated with surgery and chemotherapy were randomized to take either 300 mg of olaparib or a placebo twice a day for one year. was assigned from.
Patients on olaparib had a three-year aggressive disease-free survival rate — no recurrent breast cancer or other new cancers — of about 86%, compared to 77% for those taking placebo, the findings showed.
Dr. Amy Tiersten is a professor of hematology and medical oncology with the Icahn School of Medicine at Mount Sinai in New York City. She said, “We have already known for some time that PARP inhibitors have activity in patients with metastatic breast cancer, but this is the first time we have seen efficacy in an early-stage setting. This study showed a substantial reduction in risk has seen recurrence in this population and, therefore, the potential to cure more patients with early breast cancer associated with BRCA.”
Tut said the side effects were in line with previous studies of olaparib. The most serious common side effects included anemia, low white blood cell count, and fatigue.
Tut said the study shows the importance of performing genetic testing on cancer patients, to look for traits and mutations that can be exploited to improve treatment and survival.
“There is certainly a case for a change in mindset in the community where we use germline genetic testing,” Tut said. “We have classically thought of it as something to determine someone’s disease risk and perhaps notify other members of their family if they already have it.”
Tut notes that rather than just assessing risk, this genetic information could be used to save lives.
American Society of Clinical Oncology President Dr. Lori Pierce agreed.
“This further highlights the importance of genetic testing in appropriate patients so that we know which patients will benefit from this therapy,” Pierce said. “I think this could also open the door for additional trials of adjuvant PARP inhibitors for other BRCA1- and 2-related cancers.”
Olaparib can be an expensive drug. According to Drugs.com, a supply of sixty 100 mg tablets costs a little over $7,500.
More about the Dana-Farber Cancer Institute PARP inhibitor.
SOURCES: Andrew Tut, MBCHB, PhD, Director, Breast Cancer Now Toby Robbins Research Centre, Cancer Research Institute, London; Lori Pierce, MD, president, American Society of Clinical Oncology, Alexandria, VA; Amy Tiersten, MD, professor, hematology and medical oncology, Icahn School of Medicine at Mount Sinai, New York City; Presentation, American Society of Clinical Oncology, June 3, 2021, online