Multicenter phase 2 study of DHP107 (oral paclitaxel) versus intravenous paclitaxel in patients with HER2-negative recurrent or metastatic breast cancer

DHP107 is an oral paclitaxel enabling administration of paclitaxel without Cremophor EL, a vehicle used to improve the solublity of intravenous (IV) paclitaxel. The randomized phase 2 OPERA study, in the USA and Czech Republic, investigated efficacy and safety of DHP107 versus IV paclitaxel in patients with HER2-negative recurrent or metastatic breast cancer (R/M BC). The study included 72 patients who were randomized 2:1 to DHP107 (n=48) or IV paclitaxel (n=24). There was one complete response and 11 partial responses with DHP107 (ORR 25.0%; 90% CI 15.1-37.3) and six partial responses with IV paclitaxel (ORR 28.6%; 90% CI 13-2-48.7; p=0.7559). Median progression-free survival and overall survival were 5.5 months and 17.1 months, respectively for DHP107 and 4.7 months and 13.2 months, respectively, for IV paclitaxel (p=0.8018 and p=0.7629, respectively). Common all-grade adverse events were diarrhea (68.8%), nausea (64.6%), and fatigue (52.1%) for DHP107 and fatigue (47.6%), peripheral neuropathy (42.9%), and alopecia (42.9%) for IV paclitaxel. The authors conclude that DHP107 is a tolerable and feasible treatment for patients with HER2-negative R/M BC, with similar efficacy and safety compared with IV paclitaxel.