Vicriviroc

Vicriviroc is an experimental antiretroviral drug that was under development for the treatment of HIV/AIDS. It belongs to a class of drugs known as CCR5 receptor antagonists, which work by blocking the CCR5 co-receptor on the surface of certain immune cells that HIV uses to enter and infect the cells.

History

Vicriviroc was developed by Schering-Plough, a pharmaceutical company that is now part of Merck & Co.. The drug was first synthesized in the late 1990s and entered clinical trials in the early 2000s. However, development of vicriviroc was discontinued in 2010 after it failed to meet its primary endpoint in a Phase III clinical trial.

Mechanism of Action

Vicriviroc works by binding to the CCR5 receptor on the surface of certain immune cells, such as T cells and macrophages. This prevents HIV from attaching to the receptor and entering the cell, thereby blocking the virus's ability to replicate and spread.

Clinical Trials

Several clinical trials were conducted to evaluate the safety and efficacy of vicriviroc in patients with HIV/AIDS. These trials showed that vicriviroc was generally well tolerated and could reduce viral load in patients with CCR5-tropic HIV. However, in a Phase III trial, vicriviroc failed to show a significant improvement over existing treatments, leading to the discontinuation of its development.

Future Prospects

Despite the discontinuation of vicriviroc, research into CCR5 antagonists continues, as these drugs offer a different mechanism of action to existing antiretroviral therapies. Other CCR5 antagonists, such as maraviroc, have been approved for use in the treatment of HIV/AIDS.