Temsavir (BMS626529) is a novel attachment inhibitor that targets HIV-1 gp120 and prevents its binding to CD4+ T cells.

Temsavir的半最大有效浓度（EC50）值对绝大多数病毒分离物均<10 nM。针对LAI病毒，Temsavir展现出平均EC50值为0.7±0.4 nM。对于最敏感的病毒，Temsavir的EC50为0.01 nM，而对于最不敏感的病毒，其EC50值>2,000 nM。在不同人体组织的几种细胞类型中检查了Temsavir的细胞毒性概况。在培养3或6天后，观察到MT-2（T淋巴细胞）、HEK293（肾）、HEp-2（喉）、HepG2（肝）、HeLa（宫颈）、HCT116（结直肠）、MCF-7（乳腺）、SK-N-MC（神经上皮）、HOS（骨）、H292（肺）和MDBK（牛肾）细胞中的CC50值>200 μM。在6天的培养后，T细胞系PM1和PBMCs分别获得105和192 μM的CC50值。这些结果表明Temsavir在细胞培养中表现出低细胞毒性。Temsavir针对一系列临床分离物展现出广谱的抗病毒活性，50%抑制浓度（IC50）范围从亚nM级别到>0.1 μM。

Micro BioSpin 6 columns are used to measure the binding of [3H]BMS-488043 or [3H]BMS-626529 to gp120. Binding solutions (30 μL) containing 25 mM Tris-HCl (pH 7.5), 125 mM NaCl, 50 nM gp120JRFL, and serial dilutions of [3H]BMS-488043 or [3H]BMS-626529 are allowed to equilibrate and then adsorbed to a MicroBioSpin 6 column. The column is centrifuged (~14,000 rpm) for 5 min, the eluent is collected, and radioactivity is determined with a scintillation counter. To measure dissociative kinetics, 150 nM [3H]BMS-626529 or 90 nM [3H]BMS-488043 is incubated with 60 nM gp120 at ambient temperature for 1 h to achieve equilibrium binding, and then a large molar excess (14-fold) of soluble CD4 protein is added to drive dissociation. Aliquots are taken at the indicated time intervals, adsorbed to a spin column, and centrifuged, and the radioactivity in the eluent is quantitated. Comparison of the tritium signal from parallel samples with and without the soluble CD4 challenge allowed for the determination of the percent compound bound[1].

Cytotoxicity assays are performed in the presence of serially diluted BMS-626529 for up to 6 days, and cell viability is quantitated using an XTT assay. To determine CC50?values (concentration of drug required to kill 50% of cells), laboratory-adapted peripheral blood mononuclear cells (PBMCs) are initially plated at a density of 0.1×106?cells/mL. In the absence of compounds, the cell densities typically reach 1×106?to 1.2×106/mL after 6 days[1].