Oral paclitaxel and encequidar in patients with breast cancer: a pharmacokinetic, safety, and antitumor activity study.

"M-SD, T-CC, C-FC, Y-SL, H-SS, C-GJ, NH, and T-YC declare that they have no conflict of interest. JZ, DLC, RD, DK, and W-KC work for Athenex Inc. AQ works and K-CT worked for PharmaEssentia Corporation. HT works for Zenith Technology."

"Funding: The authors disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: This work was supported by Athenex Inc. USA and PharmaEssentia Corporation, Taiwan."

"This multicenter, single-arm, open-label, phase Ib study was conducted in six medical centers in Taiwan. All patients received oPAC + E (205 mg/m2 oral paclitaxel with 15 mg encequidar methanesulfonate monohydrate, equivalent to 12.9 mg free base) for 3 consecutive days weekly for up to 16 weeks. Two dose reductions of oPAC (to 165 and 130 mg/m2) were allowed for treatment-related toxicities. Plasma samples were collected at weeks 1 and 4 to determine paclitaxel concentration. PK, ORR, and safety were assessed. The trial is registered at ClinicalTrials.gov (Identifier: NCT03165955). In Taiwan, the approval number for this trial by Taiwan Food and Drug Administration is 1056018289. Registration:: ClinicalTrials.gov Identifier: NCT03165955"