CCR5 gatekeepers

Physicians who prescribe Pfizer Inc.'s Selzentry maraviroc for HIV will have a choice of two companion diagnostics involving different trade-offs: SensiTrop HIV co-receptor tropism assay from Pathway Diagnostics Corp. and Trofile HIV tropism assay from Monogram Biosciences Inc. Pathway believes its test offers greater sensitivity and accelerated turnaround time at a lower price, while Monogram says its test yields more accurate results.

Both SensiTrop and Trofile are CC chemokine receptor 5 HIV tropism assays. Pathway launched its test last month, while Monogram (MGRM, South San Francisco, Calif.) launched its test in August, when FDA approved Selzentry for use in combination with other antiretroviral agents for treatment-experienced adults infected with CCR5-tropic HIV-1 (see BioCentury, Sept. 10). ...