New HIV research offers hope amid drug resistance and transmission challenges

Kenyan-led HIV research offers new evidence on drug resistance, treatment and preventing mother-to-child transmission.[Courtesy]

For many people living with HIV, taking medication every day has become part of life, a routine that allows them to work, raise families and live longer. But behind the success of HIV treatment lies a growing challenge: what happens when the medicines that have kept the virus under control begin to fail?

Across Africa, where millions of people rely on antiretroviral therapy (ART), health experts are now grappling with new questions. How can patients who develop resistance to HIV drugs be treated effectively? Can older adults living with HIV safely take simpler treatment options? And how can mothers and babies be better protected from HIV transmission?

New evidence presented at the 26th International AIDS Conference in Rio de Janeiro, Brazil, is providing answers to some of these questions, with researchers from Kenya contributing findings that could influence future HIV treatment decisions across the continent.

The studies, led by researchers from the Centre for Epidemiological Modelling and Analysis (CEMA) at the University of Nairobi, focused on critical areas affecting people living with HIV drug resistance, ranging from treatment among older adults to preventing HIV transmission among pregnant and breastfeeding women.

Dr Loice Ombajo, a Principal Investigator and CEMA Co-Director, says the findings highlight the importance of generating evidence from African populations because treatment challenges experienced on the continent require solutions that reflect local realities.

"HIV treatment has transformed millions of lives, but we must continue generating evidence to address emerging challenges, especially among populations that have often been underrepresented in research, including older adults, people experiencing treatment failure, and pregnant and breastfeeding women, ” said Dr Ombajo.

One of the major studies presented at the conference was the Ndovu Study, a multi-country research project involving Kenya, Tanzania, Mozambique and Lesotho.

The study examined patients who were experiencing treatment failure while taking dolutegravir (DTG)-based antiretroviral therapy - a medicine that has become one of the main pillars of HIV treatment programmes in sub-Saharan Africa.

For years, dolutegravir has been considered highly effective because of its ability to rapidly suppress HIV and its high barrier to resistance. However, as its use has expanded across the continent, researchers have increasingly documented cases where some patients develop resistance, thus creating uncertainty on the best treatment options.

“While resistance to dolutegravir has historically been considered rare, increasing use of DTG-based antiretroviral therapy across sub-Saharan Africa has led to increasing recognition of emerging drug resistance,” Dr Ombajo added.

The Ndovu Study analysed resistance patterns among the first 2,994 participants enrolled across 131 sites in Kenya. All participants had been receiving dolutegravir-based treatment for at least six months.

Patients who developed major drug resistance mutations linked to dolutegravir were enrolled in a clinical trial to determine which treatment option would provide better outcomes.

Between September 2025 and April 2026, 72 participants were randomly assigned to either continue with standard-dose dolutegravir treatment or switch to a ritonavir-boosted darunavir (DRV/r)-based regimen.

The early findings showed a significant difference between the two groups. After one month, 80 per cent of participants receiving the DRV/r-based treatment had recorded a reduction in viral load compared with 19 per cent among those who continued on dolutegravir.

By the third month, 83 per cent of participants on the DRV/r regimen had achieved viral suppression, compared with 13 per cent among those who remained on dolutegravir.

For patients living with HIV, viral suppression is a critical milestone because it means the virus is reduced to levels where it cannot damage the immune system and cannot be sexually transmitted.

Dr Ombajo says the findings provide important guidance for healthcare providers managing patients whose treatment is no longer working.

"There is currently limited evidence to guide the management of dolutegravir resistance among people living with HIV. Through the Ndovu Study, we are generating much-needed evidence to inform treatment decisions for patients who develop resistance, ” she said.

The researchers say the results suggest that patients with major dolutegravir resistance mutations may benefit more from switching treatment rather than continuing with the same regimen.

However, they warn that access to HIV drug resistance testing remains a challenge in many African countries, meaning some patients may continue taking medicines that are no longer effectively controlling the virus.

The study findings also triggered an early review by an independent safety monitoring board, which recommended stopping randomisation to the dolutegravir treatment arm after observing better outcomes among participants receiving the alternative treatment.

Beyond the challenge of drug resistance, researchers also turned their attention to pregnant and breastfeeding women  living with HIV, a group where maintaining viral suppression is critical in protecting the next generation from infection.

While advances in HIV treatment have significantly reduced mother-to-child transmission, experts say gaps remain, especially when mothers have high levels of the virus in their bloodstream during pregnancy or breastfeeding.

The Ndovu Study examined the experiences and outcomes of pregnant and breastfeeding women who had persistent viraemia, a situation where HIV remains detectable in the blood despite being on treatment.

The concern is that when a mother has a high viral load, the risk of transmitting HIV to her baby increases, particularly during pregnancy, delivery or breastfeeding.

Globally, infants account for about 10 per cent of new HIV infections, with poor adherence to treatment and uncontrolled viral load among pregnant and breastfeeding women being among the major contributors.

Researchers followed 109 pregnant and breastfeeding women receiving dolutegravir-based treatment to understand their treatment challenges and outcomes.

The findings showed that most of the women were aged 25 years and above, had been on HIV treatment for more than one year, and had high viral loads of more than 10,000 copies per millilitre.

However, the study offered a positive message: additional adherence support helped more than half of the women achieve viral suppression within three months while remaining on the same treatment.

For healthcare providers, the findings underline the importance of early identification of women struggling with treatment adherence and providing targeted support before complications arise.

Dr Ombajo says routine viral load monitoring remains a key tool in preventing HIV transmission from mothers to their babies.

“Timely viral load testing and targeted adherence interventions are essential in ensuring mothers achieve viral suppression and reducing the risk of children acquiring HIV,” she said.

The findings come at a time when countries across Africa continue to strengthen programmes aimed at eliminating new HIV infections among children.

Decades of progress in antiretroviral therapy mean that many people diagnosed with HIV are now living into old age. However, longer life expectancy has also created new healthcare questions, including whether older adults can safely transition to simpler treatment options.

The researchers say the evidence generated from African settings is important because treatment decisions must reflect the realities faced by patients and healthcare workers on the continent.

In Kenya, HIV programmes have made major progress over the years, with increased access to testing, treatment and viral load monitoring helping millions of people live healthier lives.

However, health experts say new challenges require continued investment in research, especially as the HIV population changes.

Dr Ombajo says the goal is to ensure that scientific evidence directly translates into better care for patients.

“By conducting large, multi-country clinical studies and working closely with health ministries,  healthcare workers and research institutions, we can ensure that HIV treatment decisions are informed by evidence generated from the populations most affected by the epidemic,” she said.

The studies were conducted through collaboration between the University of Nairobi’s Department of Clinical Medicine and Therapeutics, Kenya’s Ministry of Health through the National AIDS and STI Control Programme (NASCOP), healthcare facilities, county health teams and research partners from Tanzania, Mozambique and Lesotho.