Fostemsavir is in clinical development for human immunodeficiency virus-1 (HIV-1) infection in heavily treatment-experienced adults. HIV is a virus that damages the cells in the immune system and weakens the body’s ability to fight everyday infections and diseases. HIV infection is incurable but there are effective treatments that enable most infected people to live a healthy life. Antiretroviral (ARV) medicines are used to treat HIV. However, poor adherence and the subsequent development of drug resistance is one reason why HIV treatment can fail. A drug-resistant HIV strain is one which is less susceptible to the effects of one or more anti-HIV drugs. For highly treatment-experienced patients who have failed on a number of treatment regimens and have limited treatment options, complex regimens including drugs to which the virus is partially resistant may be required.
Fostemsavir is given orally as a tablet. It is an ARV medicine that prevents HIV from attaching to host cells. It acts by binding to a specific protein on the surface of the virus which prevents the virus from attaching to the host immune cells. This first-in-class mechanism of action has the potential to have full activity against HIV strains that have developed resistance. If licensed, fostemsavir will offer a treatment option for patients with HIV-1 infection in heavily treatment-experienced adults who have limited treatment options available.
Bulevirtide is in clinical development for the treatment of chronic hepatitis Delta virus infection in adult patients with compensated liver disease. Hepatitis D is a viral infection of the liver that is dependent on the patient already being infected with hepatitis B virus. The co-infection is thought to be more severe and cause more damage to the liver than hepatitis B alone. Currently there are limited treatment options for the treatment of patients with chronic hepatitis D virus infection.