Chemical modification has been performed on an orally bioavailable and potent CCR5 antagonist, sulfoxide compound 4, mainly focusing on replacement of the [6,7]-fused 1-benzazepine nucleus. We designed, synthesized, and evaluated the biological activities of ring-expanded [6,8]-, [6,9]-, and [6,10]-fused compounds containing S-sulfoxide moieties, which led to the discovery of 1-benzazocine and 1-benzazonine compounds that exhibited potent inhibitory activities (equivalent to compound 4) in a binding assay. In addition, 1-benzazocine compounds possessing the S-sulfoxide moiety ((S)-(-)-5a,b,d,e) showed greater potency than compound 4 in a fusion assay. From further investigation in a multi-round infection assay, it was found that 1-isobutyl-1-benzazocine compound (S)-(-)-5b, containing the S-{[(1-propyl-1H-imidazol)-5-yl]methyl}sulfinyl group, showed the most potent anti-HIV-1 activity (IC90=0.81 nM, in MOLT4/CCR5 cells). Compound (S)-(-)-5b (TAK-652) also inhibited the replication of six macrophage-tropic (CCR5-using or R5) HIV-1 clinical isolates in peripheral blood mononuclear cells (PBMCs) (mean IC90=0.25 nM). It was also absorbed after oral administration in rats, dogs, and monkeys and was thus selected as a clinical candidate. The synthesis and biological activity of the 1-benzazocine compound (S)-(-)-5b and its related derivatives are described.

This paper is available online at http://dmd.aspetjournals.org ABSTRACT:To evaluate effects of multiple dosing of ketoconazole (KTZ) on hepatic CYP3A, the pharmacokinetics of intravenous midazolam (MDZ, 0.5 mg/kg) before and during multiple dosing of KTZ were investigated in beagle dogs. KTZ tablets were given orally to dogs

In dogs, KTZ at a therapeutic dose may change the pharmacokinetics of CYP3A12 substrates as a result of inhibition of their biotransformation. Furthermore, no influence of KTZ on the pharmacokinetics of CYP1A1/2, CYP2C21, and CYP2D15 substrates are likely. In clinical practice, adverse drug effects may develop when KTZ is administered concomitantly with a drug that is primarily metabolized by CYP3A12.

Background:This phase I first-in-human study was conducted in Japanese patients to investigate the safety, pharmacokinetics (PKs), and determine the maximum tolerated dose (MTD) of oral TAK-285, a novel dual erbB protein kinase inhibitor that specifically targets human epidermal growth factor receptor (EGFR) and HER2.Methods:The TAK-285 dose was escalated until MTD was determined. A second patient cohort received TAK-285 at the MTD for at least 4 weeks.Results:In all, 26 patients received TAK-285 at doses ranging from 50 to 400 mg once daily (q.d.) or twice daily (b.i.d.); 20 patients made up the dose escalation cohort and the remaining 6 patients were the repeated administration cohort. TAK-285 was well tolerated. Dose-limiting toxicities noted in two patients who received 400 mg b.i.d. were grade 3 increases in aminotransferases and grade 3 decreased appetite. Consequently, the MTD was determined to be 300 mg b.i.d. Absorption of TAK-285 was rapid after oral dosing, and plasma exposure at steady-state increased in a dose-proportional fashion for doses ranging from 50 to 300 mg b.i.d. A partial response was observed for one patient with parotid cancer who received 300 mg b.i.d.Conclusion:The toxicity profile and PK properties of oral TAK-285 warrant further evaluation.