The human immunodeficiency virus (HIV) is increasingly becoming resistant to some of the most common drugs used to prevent and treat the deadly virus. According to a new study published in The Lancet Infectious Diseases Journal, patients will be forced to choose more expensive and toxic second-line therapies. The research also increases pressure on institutions and pharma companies to develop new drugs to fight HIV before the current drugs become ineffective.
HIV-resistant virus going unnoticed in Africa
Scientists led by Dr. Ravi Gupta of the University College of London used data from 1,926 patients from 36 countries. They found that in Africa, 60% patients were resistant to Tenofovir, the most commonly used HIV prevention and treatment drug. The figure was just 20% in Europe. Researchers looked at patients who were given Tenofovir between 1998 and 2015, but the treatment failed.
Dr Ravi Gupta said it was a major concern because Tenofovir is one of the safest and most effective drugs against the HIV with minimal side effects. He said treatment and monitoring of patients must be improved to prevent the resistant HIV strains from spreading quickly. The problem is more severe in Africa where the drug-resistant virus often goes unnoticed due to lack of monitoring, and could spread to others.
Reasons why the virus develops drug resistance
Patients taking the drug Nevirapine also have higher odds of drug-resistant HIV. What’s more, people taking Lamivudine were about 50% more likely to have drug-resistance than those taking Emtricitabine. Gupta said the drug-resistance could develop due to two reasons. One, when patients miss doses or don’t take medication regularly, there is less than recommended dose of the drug in the body. As a result, the virus starts replicating and mutating, developing resistance to the drug. Second, when they are infected by an AIDS patient with a drug-resistant strain of the virus.
The study found that drug-resistant HIV reproduces itself as fast as the non-resistant ones. It means the virus can be passed on to other individuals. The market availability of less suitable, second-line drugs is increasing. But they are much more expensive and have more side effects. Scientists estimate that about 8% to 18% of HIV patients in sub-Saharan African who take Tenofovir will develop resistance during the first year of treatment.