In December, the U.S. Food and Drug Administration (FDA) approved olaparib (Lynparza) for the maintenance treatment of adult patients with germline BRCA-mutated metastatic pancreatic adenocarcinoma whose disease has not progressed on at least 16 weeks of a first-line platinum-based chemotherapy regimen, according to AstraZeneca and Merck.
The agent is now the only PARP inhibitor approved for this patient population, which follows a positive recommendation from the agency’s Oncologic Drugs Advisory Committee that previously voted 7 to 5 in favor of the approval.
In 2018, the FDA expanded the approved use of Lynparza (olaparib tablets) to include the treatment of patients with certain types of breast cancer that have spread (metastasized) and whose tumors have a specific inherited (germline) genetic mutation, making it the first drug in its class (PARP inhibitor) approved to treat breast cancer, and it is the first time any drug has been approved to treat certain patients with metastatic breast cancer who have a “BRCA” gene mutation.
What is PARP? A substance that blocks an enzyme in cells called PARP. PARP helps repair DNA when it becomes damaged. DNA damage may be caused by many things, including exposure to UV light, radiation, certain anticancer drugs, or other substances in the environment. In cancer treatment, blocking PARP may help keep cancer cells from repairing their damaged DNA, causing them to die. PARP inhibitors are a type of targeted therapy. Also called poly (ADP-ribose) polymerase inhibitor.
“Patients with advanced pancreatic cancer historically have faced poor outcomes due to the aggressive nature of the disease and limited treatment advances over the last few decades. (olaparib) is now the only approved targeted medicine in biomarker-selected patients with advanced pancreatic cancer,” Dave Fredrickson, executive vice president, head of the oncology business unit, AstraZeneca, said in a press release.
The FDA made its decision based on data from the phase III POLO trial, which showed a progression-free survival (PFS) benefit with olaparib compared with placebo in this setting. In the randomized, double-blind, placebo-controlled trial, researchers evaluated the efficacy of olaparib as maintenance therapy in 154 patients who had a germline BRCA1 or BRCA2 mutation and metastatic pancreatic cancer, which had not progressed during first-line platinum-based chemotherapy.2
The median PFS with the PARP inhibitor was 7.4 months compared with 3.8 months with placebo (HR, 0.53; 95% CI, 0.35-0.81; P = .0035). In addition, after 2 years, 22.1% of patients had no disease progression versus 9.6% of those who received placebo.
Additional results showed that the objective response rate was 23.1% with olaparib compared with 11.5% in the placebo arm (odds ratio, 2.30); 11.1% (n = 2) of patients on olaparib achieved a complete response compared with 0 on placebo. The median duration of response was 24.9 months in the olaparib arm versus 3.7 months with placebo.
After 1 year, 33.7% of patients receiving olaparib showed no signs of disease progression compared with 14.5% of those who received a placebo.
Adverse events occurring in ≥10% of patients receiving olaparib included fatigue/asthenia (60%), nausea (45%), abdominal pain (34%), diarrhea (29%), anemia (27%), decreased appetite (25%), constipation (23%), vomiting (20%), back pain (19%), arthralgia (15%), rash (15%), thrombocytopenia (14%), dyspnea (13%), neutropenia (12%), nasopharyngitis (12%), dysgeusia (11%), and stomatitis (10%).
The most frequent grade ≥3 AEs on the olaparib arm were anemia (11%), fatigue/asthenia (5%), decreased appetite (3%), abdominal pain (2%), vomiting (1%) and arthralgia (1%). AE-related dose interruptions occurred in 35% of the olaparib arm, with AE-related dose reductions occurring in 17% of this cohort. Six percent of the olaparib arm discontinued treatment due to AEs.
“Metastatic pancreatic cancer patients have been waiting a long time for new therapy options for their devastating disease. Today’s approval of LYNPARZA provides an exciting new treatment option for patients with germline BRCA-mutated metastatic pancreatic cancer,” Julie Fleshman, president and CEO, Pancreatic Cancer Action Network, said in a news release.