Niraparib is a poly (ADP-ribose) polymerase (PARP) inhibitor used in the maintenance treatment of patients with advanced or platinum-sensitive, recurrent ovarian cancer. The PRIMA trial demonstrated that niraparib significantly improved progression-free survival in patients with newly diagnosed advanced ovarian cancer who had a response to first-line platinum-based chemotherapy.1 Researchers discussed the impact of age on the efficacy and safety of treatment with niraparib.
In this double-blind, placebo-controlled phase 3 trial, treatment with niraparib in patients with newly diagnosed, advanced, high-grade serous or endometroid ovarian, primary peritoneal, or fallopian tube cancer was evaluated. Eligible patients had experienced a complete or partial response to first-line platinum-based chemotherapy. Patients were randomized to receive either a fixed starting dose of 300 mg niraparib or a placebo once daily. The protocol was later amended to add an individualized starting dose of 200 mg once daily for patients with body weight <77 kg or platelet count <150,000 cells/mL. All other patients received 300 mg once daily. Patients were evaluated by age-group to analyze efficacy and safety of niraparib, with a primary end point of progression-free survival.
Of 733 enrolled patients, 444 were aged <65 years, 289 were aged ≥65 years, and 76 were aged >75 years. Compared with placebo, the efficacy of niraparib was comparable in patients aged <65 years and those aged ≥65 years as well as in patients aged <75 years and those aged ≥75 years. Patient-reported outcomes and quality of life were similar in all age-groups.
Adverse events, specifically those of grade ≥3, were similar in patients aged <65 years and those aged ≥65 years, as well as in patients aged <75 years and those aged ≥75 years. There was a slight increase in grade ≥3 thrombocytopenia in patients aged ≥65 years and those aged ≥75 years.
The rate of grade ≥3 thrombocytopenia was lower in patients receiving the individualized starting dose compared with patients receiving a fixed starting dose. With implementation of the individualized starting dose, rates of grade ≥3 thrombocytopenia were reduced from 42.8% to 18.0% in patients aged <65 years and from 57.0% to 26.1% in patients aged ≥65 years. Similarly, rates of grade ≥3 thrombocytopenia decreased from 46.4% to 19.7% in patients aged <75 years and from 62.2% to 35.3% in patients aged ≥75 years.
Researchers conclude that the efficacy and safety of treatment with niraparib was similar regardless of age-group. In addition, quality of life was consistent among the groups. Implementation of an individualized starting dose regimen improved rates of grade ≥3 thrombocytopenia events in all age-groups.
Abstract 347. ESGO 2020.
Reference
- Gonzalez-Martin A, Pothuri B, Vergote I, et al; PRIMA/ENGOT-OV26/GOG-302 Investigators. Niraparib in patients with newly diagnosed advanced ovarian cancer. N Engl J Med. 2019;381:2391-2402.