PhenoSense Entry

PhenoSense® Entry

PhenoSense® Entry provides a direct and quantitative measurement of how a patient's virus responds to enfuvirtide (FUZEON®). 

PhenoSense® Entry assesses resistance to enfuvirtide, which interacts with glycoprotein gp41 of the HIV envelope. The test also assesses resistance to entry inhibitors that interact with gp120 (eg, chemokine receptor antagonists, attachment inhibitors) and is used in their clinical development. It is used for assessing resistance to current and future entry inhibitors.

Alternative approaches may not account for the high genetic heterogeneity observed in this part of the virus.

PhenoSense® Entry is a commercially available test for testing resistance to entry inhibitors. The assay assesses resistance to enfuvirtide, which interacts with glycoprotein gp41 of the HIV envelope.

Phenosense Entry Table

Genotyping may be insufficient because data have shown that areas outside of the envelope impact enfuvirtide susceptibility. This may explain why a wide range of fold changes† has been observed with similar mutational patterns.

Together with PhenoSense® GT, a combination phenotype and genotype drug resistance test, and PhenoSense® Integrase, PhenoSense® Entry provides the most complete picture of resistance to antiretroviral medications2.

†Fold change: A ratio of the drug concentration needed to inhibit the patient’s virus relative to that of a wild-type control strain.

 

FUZEON is a registered trademark of Genentech USA, Inc. and Trimeris, Inc.

References
1. Mink M, Greenberg ML, Mosier S, et al. Impact of HIV-1 gp41 amino acid substitutions (positions 36-45) on susceptibility to T-20 (enfuvirtide) in vitro. Analysis of primary virus isolates recovered from patients during chronic enfuvirtide treatment and site-directed mutants in NL4-3 [abstract]. Antivir Ther. 2002;7:S17.

2. Volpe J, Ward D, Napolitano L, et al. Five Antiretroviral Drug Class–Resistant HIV-1 in a Treatment-Naïve Patient Successfully Suppressed with Optimized Antiretroviral Drug Selection. JIAPAC. 2015;14(5) 398-401.