Snapshot
- A 55-year-old man presents to the HIV clinic for a follow-up visit. He was recently diagnosed with HIV and was started on first-line highly active antiretroviral therapy (HAART). However, his CD4 count at his last visit remained low. Drug resistance analysis of the HIV strain was sent at that time and revealed 3 major mutations causing the virus to be resistant to many first-line agents. The analysis also revealed that the HIV strain was CCR5-tropic. The patient was started on maraviroc.
Introduction
- Drugs
- enfuvirtide
- prevents penetration of HIV into CD4+ T-cells
- maraviroc
- prevents attachment of HIV into CD4+ T-cells
- enfuvirtide
- Clinical use
- a class of highly active antiretroviral therapy (HAART)
- often used as second-line in patients with drug resistance to first-line agents
Enfuvirtide
- Mechanism of action
- binds to gp41, which inhibits HIV entry into the cell
- Adverse effects
- injection site skin reaction
- gastrointestinal upset
- fatigue
Maraviroc
- Mechanism of action
- binds to CCR5, which is a protein on the surface of T-cells and monocytes
- inhibits the interaction of CCR5 with gp120 on HIV, thus inhibiting docking
- Clinical use
- requires assay showing that the virus is CCR5-tropic, which indicates that the virus is infecting cells with CCR5 expression (vs CXCR4), making it susceptible to the drug
- Adverse effects
- rash
- gastrointestinal upset
- immunosuppression