gut-restrict. P-gp inh. for oral paclitaxel combo
efficacious in Ph. III, NDA filed but CRL issued
from opt. of tariquidar
J. Med. Chem., Mar. 17, 2021
Athenex / Hanmi Pharmaceutical, Seoul, KR
The Athenex/Hanmi Pharmaceutical P‑gp transporter inhibitor (encequidar) is a gut-restricted compound intended to reduce efflux and increase absorption of the IV drug, paclitaxel to enable oral paclitaxel delivery. The use of transporter inhibitors in preclinical settings to improve drug exposure is well-established, and similar use in humans in various contexts has been often discussed but has seen little success. This drug is an interesting overall case study for deliberately inducing a DDI, leveraging a transporter inhibitor to make an IV drug (paclitaxel) orally bioavailable, and the paper covers preclinical and clinical development in detail. Oral combination of encequidar and paclitaxel demonstrated efficacy and tolerability with reduced neuropathy and no hypersensitivity (since the IV excipient polyoxyl-35 castor oil was obviated) in…