A Phase III, Randomised, Double Blind, Placebo Controlled, Multicentre Study of Olaparib Maintenance Monotherapy in Patients With BRCA Mutated Advanced (FIGO Stage III-IV) Ovarian Cancer Following First Line Platinum Based Chemotherapy (SOLO-1)

Trial ID # NCT01844986; SOLO-1
Phase III
Drug Class DNA Damage Repair Pathway Inhibitors:PARP
Drug Name Olaparib
Alternate Drug Names AZD2281, Lynparza
Drugs in Trial Olaparib
Eligible Participant

Stage III or IV, BRCA MUT, high grade serous or endometrioid, CR or PR after first-line therapy

Patients Enrolled

451

Therapy Setting

Maintenance

Study Design

Randomized

Endpoints

PFS, OS, PFS2, TFST, evaluated per RECIST

Biomarkers

BRCA1/2 MUT; Exploratory: timing of surgery, residual disease status after surgery, CR/PR after chemo

Efficacy

Ola maint (n=260) vs Placebo (n=131), at 41 months median follow up:

PFS: NR vs 14.1 months, HR: 0.30 (0.23-0.41, P<0.0001)
PFS2: NR vs 41.9 months, HR: 0.50 (0.35-0.72, P=0.0002)
TFST: 51.8 vs 15.1 month, HR: 0.30 (0.22-0.40, P<0.0001)

Exploratory analyses:
Upfront surgery: PFS: NR vs 15.3 months; HR: 0.31 (0.21–0.46)
Interval surgery: PFS: 33.6 vs 9.8 months; HR: 0.37 (0.24–0.58)
Residual disease after surgery: PFS: 29.4 vs 11.3 months; HR: 0.44 (0.25–0.77)
No residual disease after surgery: PFS: NR vs 15.3 months; HR: 0.33 (0.23–0.46)
CR after chemotherapy: PFS: NR vs 15.3 months; HR: 0.34 (0.24–0.47)
PR after chemotherapy: PFS: 30.9 vs 8.4 months; HR: 0.31 (0.18–0.52)

Clinically Significant Adverse Events

Ola maint vs Placebo:
Serious AE: any (21 vs 12%), 3 deaths due to AML in olaparib arm (1.2%)
Grade 3-4 AE: any (39 vs 18%), anemia (22 vs 2%)

Conclusion

Considerably improved PFS for BRCA MUT patients with olaparib maintenance treatment

Reference

Moore KN et al. Maintenance Olaparib in Patients with Newly Diagnosed Advanced Ovarian Cancer. NEJM (2018) Oct 21
https://www.ncbi.nlm.nih.gov/pubmed/30345884

Colombo N et al. Adverse events (AEs) with maintenance olaparib in newly diagnosed patients (pts) with advanced ovarian cancer (OC) and a BRCA mutation (BRCAm): Phase III SOLO1 trial. J Clin Oncol (2019) 37 (suppl; abstr 5539)
https://meetinglibrary.asco.org/record/175221/abstract

Matthews CA et al. Maintenance olaparib after platinum-based chemotherapy in patients (pts) with newly diagnosed advanced ovarian cancer (OC) and a BRCA mutation (BRCAm): Efficacy by surgical and tumor status in the Phase III SOLO1 trial. J Clin Oncol (2019) 37 (suppl; abstr 5541)
https://meetinglibrary.asco.org/record/175279/abstract