Research Roundup: HIV drug resistance, the 21st Century Cures Act, and more
The HIV virus is rapidly developing resistance to common antiretroviral drugs. In low- and middle-income countries (LMICs), 10 percent of patients starting antiretroviral therapy (ART) and 40 percent of patients restarting treatment are infected with drug-resistant strains. The leading contributor to drug resistance is failure to adhere to treatment—a problem that plagues nearly three-fourths of patients in LMICs. In low-resource settings, many patients only have access to older, more toxic drugs, and more than one third of clinics report stock outs of HIV medicines. If action is not taken to improve treatment for these patients, drug-resistant strains of HIV-1 could result in 300,000 new infections and 425,000 deaths over the next five years.
Last week, the US Congress overwhelmingly approved the nearly 1000-page 21st Century Cures Act, a massive initiative that channels new funding into the US National Institutes of Health and alters the way the US Food and Drug Administration (FDA) regulates certain medicines and devices. While some advocates argue that it weakens the FDA’s regulatory review process, others have applauded the legislation for its potential impact on the development and approval of new antibiotics. One provision—the limited population approval pathway—would allow the FDA to approve antimicrobials and other drugs for serious or life-threatening infections based on smaller clinical trials, addressing the challenge of identifying an adequate number of clinical trial participants (i.e., patients who are infected with drug-resistant pathogens). Another component addresses the FDA’s approach to updating antimicrobial susceptibility interpretative criteria, which informs the development of diagnostics that help physicians prescribe the best antibiotics for a given infection. The provision enables the agency to rely on other organizations’ research and update its criteria accordingly, rather than reviewing the research in house—a time consuming and costly process. While the legislation will likely be signed into law by President Obama, it could take years to fully implement.
Scientists have long known that the tuberculosis vaccine offers protection against a number of pathogens and even treats certain conditions (i.e., bladder cancer and asthma), and a recent study in Cell Reports may explain why. Studies in mice and humans revealed that the Bacillus Calmette-Guerin vaccine increased glycolysis—the process of breaking down glucose—in monocytes, a type of immune cell. The effect, which lasts long after vaccination, enhances monocytes’ immunological memory—their ability to remember pathogens they have previously encountered—improving their disease detection and response capabilities. These findings could help scientists devise new strategies for boosting the immune system or its response to certain diseases.
The European Medicines Agency (EMA) released a statement last week indicating that patients treated with certain hepatitis C medicines may experience a resurgence of previously latent hepatitis B. The phenomenon applies to a new class of drugs known as direct-acting antivirals and includes Daklinza, Exviera, Harvoni, Olysio, Sovaldi, and Viekirax. While there have only been 30 reported cases, the EMA is recommending patients be tested for hepatitis B before starting treatment.