Kemri study: Over half of babies born to HIV positive mothers resistant to available ARTs
About six in 10 of the newly diagnosed babies born to HIV positive mothers are resistant to most of the currently available antiretroviral therapies (ARTs).
According to a study by the Kenya Medical Research Institute (Kemri), more than half of these infants are resistant to a class of drugs known as non-nucleoside reverse transcriptase inhibitors (NNRTIs) that prevents the HIV virus from replicating.
From the study, it is thought that the babies are born with the drug resistant mutation as a result of possible exposure to ARTs from their mothers.
HIV (human immunodeficiency virus) is a virus that attacks the body's immune system. If HIV is not treated, it can lead to AIDS (acquired immunodeficiency syndrome).
According to the country’s guidelines on HIV treatment, all individuals who test positive for HIV should be started on ART as soon as possible.
Patients are often put on ART immediately to protect them from getting ill and increase their "helper" cells (CD4 T-cells) that trigger the body's response to infections.
It is estimated that 13,000 new infant HIV infections occur annually in Kenya. To prevent transmission of the virus from mother to child (PMTCT), the country in 2014 scaled up an approach to offer all HIV-positive pregnant women treatment for life and ART prophylaxis to all exposed infants, free of charge.
“This presents a gap on the prevention on the PMTCT programme because these are infants who have vertically been infected from their mothers,” said Kemri researcher Sheila Kageha, who presented the study at the just concluded Kemri annual scientific and health (Kash) conference in Nairobi.
But the Kemri study led shows the resistance has been growing since 2014, the earliest year the team of researchers picked up samples.
They collected dried blood spots from infants below 18 months through the Kenya early infant diagnosis programme in 2014, 2017 and 2018.
In 2014, 57.9 per cent of the babies had drug-resistant mutations to some of the then commonly used NNRTIs class of ARTs. This dropped to 54.3 per cent in 2017 and rose to 58 per cent in 2018.
Some of the commonly used NNRTIs include Nevirapine (NVP) and Efavirenz (EFV).
“Our thinking is that a drug like Nevirapine has been used for a long time and the virus has gotten smarter, therefore creating mutations that can evade the drugs. Secondly, many infants are put on NVP shortly after birth as a prophylaxis. This means that they are exposed to the drug not only in the womb but also at a very early stage, further weaken the effects of the drug,” said Ms Kageha.
To make the situation worse, three in 10 (22.8 per cent) of the infants who had resistance to NNRTIs were also resistant to another class of ARTs known as nucleoside reverse transcriptase inhibitors (NRTIs) which include drugs like Zidovudine (AZT) and Lamivudine (3TC).
In 2014, 22.8 per cent of the babies had mutations resistant to NRTI. This dropped to 11.4 per cent in 2017 and rose to 14 per cent in 2018.
The rates are not alarming and have been reported almost uniformly across many other countries. According to the World Health Organisation’s report on HIV drug resistance 2021, nearly one-half of infants born to mothers infected with HIV has HIV drug resistance to one or more NNRTIs.
The WHO has since 2019 recommended the use of Dolutegravir (DTG) as the preferred first and second-line of treatment for all population groups. Similarly, the guidelines on use of antiretroviral drugs for treating and preventing HIV infection in Kenya also recommend that children be put on DTG for HIV treatment, as it is more effective, easier to take, and has fewer side effects than other currently used drugs.
Until December, child-friendly DTG was unavailable. Ministry of Health announced introducing the drug in form of a strawberry-flavoured pill that is dispersible in water and is easily tolerated by children.
“Despite most infants accessing early HIV-1 diagnosis in Kenya, data remains limited on trends of drug-resistant mutations among them,” Ms Kageha, a research scientist with Kemri said.
She called for effective prevention of mother to child transmission of HIV, adding that there is need to strengthen health information systems to capture data appropriately.
