Contagion® covered the 9th International AIDS Conference on HIV Science this week and much of the research presented at the conference made this week’s Top 5. Topics include: the successful use of oral Truvada in adolescents, a new long-acting two-drug injectable HIV regimen, and a closer look at humanized monoclonal antibody PRO 140 for HIV treatment. Additional Top 5 articles include coverage from the Biodefense World Summit, and lack of infant immunizations across the world.
With the lofty worldwide goal of putting an end to the AIDS epidemic by 2030, researchers everywhere are working to cut back on the number of new HIV diagnoses by strengthening preventive strategies. However, given the fact that adolescents and younger individuals are representative of a growing share of those living with HIV worldwide, preventive efforts need to be tailored specifically to this population.
At the 9th International AIDS Conference on HIV Science, two teams of investigators reported findings from 2 different studies that focused on preventing HIV specifically in adolescents: a daily oral tablet and a monthly vaginal ring. This article will focus on the trial regarding the daily oral tablet.
The Choices for Adolescent Prevention Methods for South Africa, or CHAMPS PlusPills, was a phase 2 study that set out to evaluate the “safety, acceptability, and use of daily oral Truvada, which contains 2 anti-HIV drugs (tenofovir and emtricitabine), as part of an HIV prevention package” for adolescents.
This was the first time that girls were included in a clinical trial of the oral tablet as a means of pre-exposure prophylaxis (PrEP) in the adolescent population.
Read more about the use of oral Truvada in adolescents, here.
The 2017 Biodefense World Summit breakout session on food safety detection was a goldmine of information with a whopping 12 presentations. Whether it was nucleic acid aptamers as bioaffinity ligands for detection of human norovirus (try saying that three times fast!), rapid detection of Enterobacteriaceae as indicator pathogen testing, or food-safety microbiology in the metagenomics era, there was a wealth of knowledge presented for those interested in food-safety detection.
Chris Taitt, PhD, from the US Naval Research Laboratory discussed the use of antimicrobial peptides as a broad-based detection method for pathogens. He highlighted the most common uses for rapid detection—food safety, environmental monitoring, biosecurity, and health monitoring—but also how he and his colleagues are looking for specific molecular markers for rapid detection. The most common approaches to rapid detection are nucleic acid-based technologies and immunoassays as they are sensitive and well-developed; however, they also require knowledge of the specific target (ie, you have to know which organism you’re looking for). Dr. Taitt noted that because of these gaps, we really need a broad-spectrum detection method without specific reagents. The use of antimicrobial peptides (AMPs) may be that new method for detection of cells. AMPs bind to multiple species and are stable to environmental extremes. The best part is that they are semi-selective, and so they can detect a broad range of targets. Dr. Taitt highlighted that a broad-based, semi-selective recognition platform, such as using AMPs, may be the next step in rapid detection in which discrimination is needed.
Continue reading coverage from the Biodefense World Summit, here.
After a total of 96 weeks of maintenance treatment, the viral suppression rates were shown to be 94% for the 2-drug regimen at dosing every 8 weeks, and 87% for dosing every 4 weeks. These results were comparable to those observed for patients on a 3-drug oral regimen (84%). Of note: “2 patients in the 8-week dosing group and 1 patient in the oral regimen group met protocol-defined virologic failure criteria; neither patient had evidence of resistance at failure,” according to the press release. Pain at the injection site was the “most commonly reported injection site reaction (ISR) reported by patients receiving injectable cabotegravir 2 and rilpivirine.”
“These study results are important because we now have data showing the durability and tolerability of long-acting viral suppression for a two-drug regimen out to 96 weeks. Administration of long-acting parenteral medication removes the daily dosing burden for patients and the LATTE-2 results showed that long-acting cabotegravir and rilpivirine maintained viral suppression, with no virologic failures in the four-week dosing group. We look forward to results from our phase 3 program with long-acting cabotegravir and rilpivirine in 2018,” stated John C Pottage Jr, Chief Scientific and Medical Officer for ViiV Healthcare in the press release.
Learn more about the new long-acting two-drug HIV regimen, here.
The efficacy results from 1 of 2 PRO 140 clinical trials should be announced in the next month, according to CytoDyn. What Dr. Pourhassan projects is a once-weekly subcutaneous self-injection antibody that protects healthy cells from HIV infection by binding to the C-C chemokine receptor type 5 (CCR5).
CCR5 is a white blood cell surface protein used by the virus to infect host cells. Paul J. Maddon, MD, PhD, the inventor of PRO 140, was credited by Dr. Pourhassan as one of the forefront researchers in CCR5’s role in HIV treatment for the past decade.
In previous trials, PRO 140 has been shown to reduce HIV viral load in the body, while maintaining a long-term reduction, according to CytoDyn. Patients observed in such trials have been on the treatment for over 2 years during the study’s extension, and have reported minimal adverse effects and toxicities—and no viral resistance.
Read more about humanized monoclonal antibody PRO 140 for HIV, here.
The percentage of children who receive full-course immunizations remains stagnant at 86%, as 12.9 million infants went unvaccinated in 2016, according to WHO and UNICEF. Since 2010, that percentage has remained stationary and continues to fall short of the global immunization coverage target of 90%. Data indicate that 64 of 194 countries fell short of meeting the 90% standard, which would require an additional 10 million children from these countries to be vaccinated. Over 70% of these children live in nations dominated by conflict and humanitarian issues.
"Most of the children that remain un-immunized are the same ones missed by health systems," says Dr Jean-Marie Okwo-Bele, director of Immunization, Vaccines and Biologicals at WHO, in a press release. "These children most likely have also not received any of the other basic health services. If we are to raise the bar on global immunization coverage, health services must reach the unreached. Every contact with the health system must be seen as an opportunity to immunize."
Pakistan, for example, remains a polio-endemic country, despite mandatory polio vaccination since 1978. Although the last case of polio in the United States occurred in 1978, Pakistan reported 20 cases of the virus in 2016, according to WHO. Polio has also recently sprung up in war-torn Syria, with health officials vigorously working to launch a major vaccination campaign to quell the outbreak. The polio virus has been eliminated from most of the world and has the potential to be eradicated entirely, with increased vaccination rates.
Continue reading about infant immunizations, here.