TY - JOUR
T1 - Discovery, Modeling, and Human Pharmacokinetics of N-(2-Acetyl-4,6-dimethylphenyl)-3-(3,4-dimethylisoxazol-5-ylsulfamoyl) -thiophene-2-carboxamide (TBC3711), a Second Generation, ETA Selective, and Orally Bioavailable Endothelin Antagonist
AU - Wu, Chengde
AU - Decker, E. Radford
AU - Blok, Natalie
AU - Bui, Huong
AU - You, Tony J.
AU - Wang, Junmei
AU - Bourgoyne, Andree R.
AU - Knowles, Vippra
AU - Berens, Kurt L.
AU - Holland, George W.
AU - Brock, Tommy A.
AU - Dixon, Richard A F
PY - 2004/4/8
Y1 - 2004/4/8
N2 - Sitaxsentan (1) (Wu et al. J. Med. Chem. 1997, 40, 1690) is our first endothelin antagonist being evaluated in clinical trials. It has demonstrated biological effects in an acute hemodynamic study in CHF (Givertz et al. Circulation 2000, 101, 2922), an open-label 20-patient pulmonary hypertension trial (Barst et al. Chest 2002, 121, 1860-1868), and a 31-patient trial in essential hypertension (Calhoun et al. AHA Scientific Sessions 2000). In a phase 2b/3 pulmonary arterial hypertension trial, once a day treatment of 100 mg of sitaxsentan statistically significantly improved 6-min walk distance and NYHA class at 12 weeks (Barst et al. Am. J. Respir. Crit. Care Med. 2004, 169, 441). We have since reported on our efforts in generating follow-up compounds (Wu et al. J. Med. Chem. 1999, 42, 4485) and recently communicated that an ortho acyl group on the anilino ring enhanced oral absorption in this category of compounds (Wu et al. J. Med. Chem. 2001, 44, 1211). Here we report an expansion of this work by substituting a variety of electron-withdrawing groups at the ortho position and evaluating their effects on oral bioavailability as well as structure-activity relationships. As a result, TBC3711 (7z) was identified as our second endothelin antagonist to enter the clinic due to its good oral bioavailability (∼100%) in rats, high potency (ETA IC50 = 0.08 nM), and optimal ETA/ETB selectivity (441 000-fold). Compound 7z has completed phase-I clinical development and was well tolerated with desirable pharmacokinetics in humans (t1/2 = 6-7 h, oral availability > 80%).
AB - Sitaxsentan (1) (Wu et al. J. Med. Chem. 1997, 40, 1690) is our first endothelin antagonist being evaluated in clinical trials. It has demonstrated biological effects in an acute hemodynamic study in CHF (Givertz et al. Circulation 2000, 101, 2922), an open-label 20-patient pulmonary hypertension trial (Barst et al. Chest 2002, 121, 1860-1868), and a 31-patient trial in essential hypertension (Calhoun et al. AHA Scientific Sessions 2000). In a phase 2b/3 pulmonary arterial hypertension trial, once a day treatment of 100 mg of sitaxsentan statistically significantly improved 6-min walk distance and NYHA class at 12 weeks (Barst et al. Am. J. Respir. Crit. Care Med. 2004, 169, 441). We have since reported on our efforts in generating follow-up compounds (Wu et al. J. Med. Chem. 1999, 42, 4485) and recently communicated that an ortho acyl group on the anilino ring enhanced oral absorption in this category of compounds (Wu et al. J. Med. Chem. 2001, 44, 1211). Here we report an expansion of this work by substituting a variety of electron-withdrawing groups at the ortho position and evaluating their effects on oral bioavailability as well as structure-activity relationships. As a result, TBC3711 (7z) was identified as our second endothelin antagonist to enter the clinic due to its good oral bioavailability (∼100%) in rats, high potency (ETA IC50 = 0.08 nM), and optimal ETA/ETB selectivity (441 000-fold). Compound 7z has completed phase-I clinical development and was well tolerated with desirable pharmacokinetics in humans (t1/2 = 6-7 h, oral availability > 80%).
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U2 - 10.1021/jm030528p
DO - 10.1021/jm030528p
M3 - Article
C2 - 15055997
AN - SCOPUS:11144356307
SN - 0022-2623
VL - 47
SP - 1969
EP - 1986
JO - Journal of Medicinal Chemistry
JF - Journal of Medicinal Chemistry
IS - 8
ER -