Objective :This post-hoc exploratory analysis of the multinational, multicenter, phase III non-inferiority OPTIMAL study (NCT03315364) evaluated the efficacy and safety of oral paclitaxel (DHP107) in patients with HER2-negative recurrent or metastatic breast cancer enrolled at Liaoning Cancer Hospital.
Methods :Patients enrolled between August 2019 and November 2020 as part of the OPTIMAL phase III trial were randomized to receive either DHP107 (200 mg/m2, twice daily) or intravenous (i.v.) paclitaxel (80 mg/m2),both administered on days 1, 8, and 15 of each 28-day cycle. Endpoints included PFS, ORR, DCR, TTF, OS, QoLand safety.
Results:A total of 53 patients were randomized at our center, of whom 52 were included in the efficacy and safety analyses (DHP107 group,n=24; i.v. paclitaxel group, n=28). At data cut-off, median PFS was 9.1 months (95% CI: 7.3-16.9) in the DHP107 group and 6.1 months(95% CI: 5.4-15.0) in the i.v. paclitaxel group (HR=0.76, 95% CI: 0.42-1.36, P=0.592). Median OS was 26.2 months(95% CI: 22.2-42.7) for DHP107 versus 16.5 months (95% CI: 11.8-29.5) for i.v. paclitaxel (HR=0.59, 95% CI: 0.31-1.13,P=0.116). At the 42-month restriction time point, the mean survival time of the DHP107 was 7.51 months longer than that of the i.v. paclitaxel (95% CI: 0.37-14.66, P=0.039),representing a relative increase of 40% (95% CI: 1.02-1.93, P=0.040). The ORR was 50.0% (95% CI: 29.1-70.9) in the DHP107 and 28.6% (95% CI: 13.2-48.7) in the i.v. paclitaxel , while the DCR was 91.7% (95% CI: 73.0-99.0) and 78.6% (95% CI: 59.0-91.7), respectively. Regarding safety, the incidence of serious adverse events (SAEs) was 16.7% in the DHP107 and 14.3% in the i.v. paclitaxel .
Conclusions This single-center exploratory analysis demonstrated that oral paclitaxel (DHP107) exhibited efficacy comparable to that of weekly i.v. paclitaxel, with a manageable and favorable safety profile. The oral formulation provides a more convenient treatment option for clinical practice.