How long does it take for Lynparza/Olaparib to work?

Olaparib takes between two months and five months to start working, depending on what cancer it is used to treat.

When used to treat ovarian cancer, olaparib may take at least3 months to start working. The trial reported that a higher proportion of patients who took olaparib were event-free for three months than those who took a placebo, an inactive treatment. This difference persisted to the end of the trial, with olaparib reducing the risk of disease progression or death by 70% compared with placebo, an inactive treatment. Most women (61%, or 158 of 260 women) did not experience cancer growth or recurrence for an average of 3.4 years.

When used to treat metastatic breast cancer, a difference between treatment with olaparib and chemotherapy was noted at 2 months. Lynparza delayed disease progression by 7 months compared with 4.2 months in patients treated with chemotherapy. People who received Lynparza were 42% less likely to have their cancer grow or spread than those who received chemotherapy. Additionally, 52% of people (87 of 167) saw their tumors shrink, compared with only 23% (15 of 166) of people who received certain chemotherapy treatments.

Kaplan-Meier plots of 1836 patients with germline BRCA-mutated HER2-negative high-risk early breast cancer from the OlympiA RCT show a difference in invasive disease-free survival between patients treated with olaparib and those treated with placebo over several months during the trial (60 months).

When used to treat metastatic castration-resistant prostate cancer, differences were noted as early as two months into treatment between trial participants assigned to olaparib and those assigned toenzalutamide or abiraterone acetate.

In a study of men withBRCA1, BRCA2 or ATM gene mutations, olaparib doubled the median time without cancer progression or death to 7.4 months, compared with 3.6 months with the hormone therapy enzalutamide or abiraterone. Overall, 56 of 162 (35%) men taking olaparib had no disease progression or death, compared with 15 of 83 (18%) men taking enzalutamide or abiraterone.

When used to treat metastatic pancreatic cancer, olaparib took longer to start working, with differences from placebo not being noticed until 5 or 6 months after the trial began. In a study of 92 patients, olaparib reduced the risk of cancer developing or coming back by 47% compared with placebo. Among patients who received olaparib, the cancer did not grow or return for 7.4 months, compared with 3.8 months for those who received a placebo.