GSK's antiretroviral HIV medicine Tivicay (dolutegravir) has been recommended by the World Health Organization (WHO) since 2018 as a preferred treatment for the virus. Now, the same agency is flagging increasing resistance to the drug in some countries.
WHO regularly tracks the good and bad news in HIV drug resistance through its HIV Drug Resistance report. This year’s report (PDF) showed high levels of HIV viral load suppression in populations receiving Tivicay-based therapy, but it’s not all good news.
The organization cited surveys from four countries that suggest rates of resistance to Tivicay are “exceeding levels observed in clinical trials,” according to a WHO press release.
The surveys showed the rate of resistance to the drug at 3.9% to 8.6% among patients with uncontrolled viral loads in Uganda, Ukraine and Malawi. Another survey from Mozambique showed a whopping 19.6% rate of resistance in people with prior treatment experience who switched to a Tivicay-containing therapy while still having high viral loads.
Importantly, the analysis focuses on "subgroups whose virus was not suppressed and the data does not indicate that resistance was prevalent in the overall population," a GSK spokesperson said in an emailed statement.
In addition, the data are not fully reflective of the global situation; only a few countries have reported survey data to WHO, the agency said.
“This medicine has demonstrated strong efficacy, safety and a high barrier to resistance in treating people living with HIV-1,” GSK's spokesperson added.
Still, the evidence "underscores the necessity for increased vigilance and intensified efforts to optimize the quality of HIV care delivery,” WHO's global HIV, hepatitis and STI program head, Meg Doherty, M.D., Ph.D., said in a statement.
Tivicay earned its WHO endorsement due to its effectiveness, easiness to take and lack of side effects compared with other drugs.