A recent preclinical animal-based study conducted by National Institutes of Health scientists reveal that early treatment with the experimental antiviral drug remdesivir significantly reduces clinical disease and damage to the lungs of rhesus macaques infected with SARS-CoV-2, the coronavirus that causes COVID-19.
This study, reports the NIH in an press release, was designed to follow dosing and treatment procedures used for hospitalized COVID-19 patients being administered remdesivir in a large-multi-center clinical trial led by NIH’s National Institute of Allergy and Infectious Diseases (NIAID).
The results, published on the preprint server bioRxiv, are not yet peer reviewed. Hence this is not clinical advance but the NIH wanted them share given the nature and severity of the pandemic and the need for information to help assists local health authority responses. Recently researchers posted a study highlighting the development of the primate model of mild-to-moderate human disease, conducted by the same team of NIAID scientists and posted to bioRxiv last month.
This current study was developed by Gilead Sciences Inc. and NIAID supported investigators and involved six groups of rhesus macaques. One group of monkeys received remdesivir and the other animals served as an untreated comparison group. Scientists infected both groups with SARS-CoV-2. Twelve hours later the treatment group received a dose of remdesivir intravenously, and then received a daily intravenous booster dose thereafter for the next six days. The scientists timed the initial treatment to occur shortly before the virus reached its highest level in the animals’ lungs.
Twelve hours after the initial treatment, the scientists examined all animals and found the six treated animals in significantly better health than the untreated group, a trend that continued during the seven-day study. They report that one of the six treated animals showed mild breathing difficulty, whereas all six of the untreated animals showed rapid and difficult breathing. The amount of virus found in the lungs was significantly lower in the treatment group compared to the untreated group, and SARS-CoV-2 caused less damage to the lungs in treated animals than in untreated animals.
The investigators note that the data supports initiating remdesivir treatment in COVID-19 patients as early as possible to achieve maximum treatment effect. The authors, from NIAID’s Rocky Mountain Laboratories in Hamilton, Montana, also note that while remdesivir helped prevent pneumonia, it did not reduce virus shedding by the animals. “This finding is of great significance for patient management, where a clinical improvement should not be interpreted as a lack of infectiousness,” they write.
Lead Investigator: Vincent Munster, PhD, Chief, Virus Ecology Unit
Team: Brandi Williamson, Friederike Feldmann, Benjamin Schwarz, Kimberly Meade-White, Danielle Porter, Jonathan Schulz, Neeltje van Doremalen, Ian Leighton, Claude Kwe Yinda, Lizzette Perez-Perez, Atsushi Okumura, Jamie Lovaglio, Patrick Hanley, Greg Saturday, Catharine Bosio, Sarah Anzick, Kent Barbian, Tomas Chilar, Craig Martens, Dana Scott, Emmie de Wit