From the Guidelines
The recommended duration of olaparib adjuvant therapy for patients with BRCA1-mutated ovarian cancer is 2 years (24 months) of continuous treatment. This recommendation is based on the most recent and highest quality study, the SOLO-1 trial, which demonstrated significant improvement in progression-free survival when olaparib was used as maintenance therapy for 2 years following response to platinum-based chemotherapy 1. The 2-year duration balances efficacy with considerations of cumulative toxicity and cost.
Key Considerations
- Olaparib is typically prescribed at a dose of 300 mg (two 150 mg tablets) taken twice daily for a total daily dose of 600 mg.
- Patients should be monitored regularly during treatment for common side effects including fatigue, nausea, anemia, and neutropenia.
- Dose reductions (to 250 mg twice daily, then 200 mg twice daily if needed) may be necessary to manage adverse effects.
- Complete blood counts should be checked monthly during the first year and periodically thereafter.
Rationale
The PARP inhibitor mechanism of olaparib exploits synthetic lethality in BRCA-mutated cancer cells, preventing DNA repair and leading to cancer cell death, which explains its particular effectiveness in BRCA1-mutated ovarian cancers. The SOLO-1 trial showed that 67% of patients treated with olaparib compared with 46% of patients treated with placebo were still alive after 7 years of follow-up 1. This significant improvement in progression-free survival and overall survival supports the use of olaparib as adjuvant therapy for 2 years in patients with BRCA1-mutated ovarian cancer.
Additional Context
Other studies, such as the PAOLA-1 and PRIMA trials, have also investigated the use of PARP inhibitors in ovarian cancer, but the SOLO-1 trial provides the most direct evidence for the recommended duration of olaparib adjuvant therapy in patients with BRCA1-mutated ovarian cancer 1.
From the Research
Olaparib Adjuvant Therapy Duration for Ovarian Cancer with BRCA1 Mutation
- The duration of olaparib (Lynparza) adjuvant therapy for ovarian cancer with BRCA1 mutation is up to 2 years, as stated in the SOLO1/GOG 3004 trial 2.
- In the SOLO1/GOG 3004 trial, patients received olaparib (300 mg twice daily) or placebo tablets orally as maintenance monotherapy for up to 2 years 2.
- The median treatment duration was 24.6 months in the olaparib group and 13.9 months in the placebo group, with a median follow-up of 4.8 years in the olaparib group and 5.0 years in the placebo group 2.
- The SOLO2/ENGOT-Ov21 trial also reported a treatment duration of up to 2 years, with a median treatment duration of 19.1 months in the olaparib group and 5.5 months in the placebo group 3, 4.
Tolerability and Safety of Olaparib Maintenance Therapy
- The tolerability of maintenance olaparib in newly diagnosed patients with advanced ovarian cancer and a BRCA mutation was analyzed in the SOLO1 trial, which reported that adverse events were manageable with supportive treatment and/or olaparib dose modification in most patients 5.
- The most common adverse events were anemia, neutropenia, nausea, fatigue/asthenia, and vomiting, which usually occurred early and were largely manageable 5.
- The study reported that 64.2% of patients still receiving olaparib at month 24 were receiving the recommended starting dose of olaparib 300 mg twice daily 5.