AMSTERDAM – A real-world study that included more than 100,000 people living with HIV infection appears to confirm that a treatment regimen based on the integrase inhibitor dolutegravir (Ticivay) suppresses the virus to undetectable levels better than therapy based on the non-nucleoside reverse transcriptase inhibitor efavirenz (Sustiva), researchers said here.
About 82.5% of patients on dolutegravir were able to achieve undetectable viral loads using a stringent 50 copies/ml assay compared with 78% of patients on efavirenz (P<0.001), said Mariana Veloso Meireles, MSc, of Brazil's Ministry of Health in Brasilia.
The study reviewed 6-month outcomes among 103,240 individuals who were given first-line therapy, she reported at the 22nd International AIDS Conference. The study confirms the decision of the Ministry of Health to recommend first-line treatment with dolutegravir, tenofovir and lamivudine in 2017, she said at a press conference sponsored by the International AIDS Society. Since 2013, the government had recommended efavirenz plus tenofovir and lamivudine for treatment of HIV infection.
The study scrutinized data from the Brazilian Ministry of Health from 2014-2017. Overall, 76.9% of the patients achieved undetectable viral loads. About two-thirds of the patients in the study were men. The average age of the group was 34 years; their average CD4-positive cell counts was 394 cells/mm3.
Meireles said that about 7.2% of the patients in the study were taking the dolutegravir regimen with tenofovir and lamivudine; 74% of the population in the study were on efavirenz. She reported that 4.9% of the patients were on a lopinavir, zidovudine, and lamivudine – and 67.2% achieved an undetectable viral load. Patients were treated with efavirenz, zidovudine, and lamivudine among 3.5% of the cohort and 72.9 % of those patients achieved undetectable viral loads. Treatment with a therapy based on the protease inhibitor atazanavir was used by 3.5% of the patients and 71.2% of those patients achieved undetectable viral loads. Other regimens had suppression rates under 70%, Meireles reported.
The researchers acknowledged several limitations of their study, including their reliance on pharmacy refill data to determine adherence to medicine, although they said that using such data has been validated as a research tool. They also noted that variables such as clinical stage, pregnancy, and other co-morbidities were not included in their analysis.
"The observed effectiveness of lamivudine, tenofovir, and dolutegravir in our cohort was markedly superior to other regimens after controlling for age, sex, adherence, and baseline CD4 cells and viral load," Meireles said. She calculated that the dolutegravir regimen was 42% superior to the efavirenz treatment, and was 51% -- 162% more effective than other regimens used by the treated population.
"Our results support the decision made by the Ministry of Health to switch its recommendation for preferred first-line antiretroviral therapy from efavirenz to dolutegravir."
"It is nice to see real world data," said Linda-Gail Bekker, MBChB, PhD, president of the International AIDS Society and professor of medicine at the Desmond Tutu HIV Foundation, Cape Town, South Africa. "I think the world is coming around to integrase inhibitors. I think the patients are telling us, and I think the data are telling us, that integrase is favorable."
She told 51˶ that studies that link dolutegravir to neural tube defects in babies born to mothers on dolutegravir could be "a real bump in the road" but she said it could help the HIV medical profession focus more on needs of women patients.
Not all was rosy for dolutegravir at IAC, however. Another study presented here found significantly higher rates of neural tube defects in offspring of women on dolutegravir at conception.
Disclosures
Meireles and Bekker disclosed no relevant relationships with industry.
Primary Source
International AIDS Conference
Meireles M, et al "Comparative effectiveness of first-line antiretroviral therapy regimens: Results from a large realworld cohort in Brazil after the implementation of Dolutegravir" IAC 2018; Abstract TUAB01.