Early data suggest efficacy extends even to newer variants of Covid-19, including the Delta variant.
Study Discovers Existing Drugs Are Effective Against Covid-19
WASHINGTON — Researchers worldwide have been racking their brains to work out a treatment for Covid-19. While vaccines are the gold standard and popular choice for prevention, therapies for people infected with Covid-19 remain in short supply.
But a new study from researchers at the University of Michigan reveals several drug contenders already in use for other purposes—including one dietary supplement—have shown to block or reduce Covid-19 infection in cells.
The study, published in the journal ‘Proceedings of the National Academy of Science,’ uses artificial intelligence-powered image analysis of human cell lines in Covid-19 infections.
The cells were treated with more than 1,400 individual US Food and Drug Administration (FDA)-approved drugs and compounds—either before or after a viral infection—and screened, resulting in 17 potential hits.
Ten of those hits were newly recognized, with seven identified in previous drug repurposing studies, including Remdesivir, one of the few FDA-approved therapies for Covid-19 in hospitalized patients.
“Traditionally, the drug development process takes a decade—and we just don’t have a decade,” said Jonathan Sexton, assistant professor of Internal Medicine at the University of Michigan’s Medical School and one of the senior authors on the paper.
“The therapies we discovered are well-positioned for phase 2 clinical trials because their safety has already been established.”
The team validated the 17 candidate compounds in several types of cells—including stem-cell-derived human lung cells—to mimic Covid-19 infection of the respiratory tract.
Nine showed anti-viral activity at reasonable doses, including lactoferrin, a protein found in human breast milk that is also available over the counter as a dietary supplement derived from cow’s milk.
“We found lactoferrin had remarkable efficacy for preventing infection, working better than anything else we observed,” Sexton said.
The early data suggest this efficacy extends even to newer variants of Covid-19, including the highly transmissible Delta variant, according to him.
The team is soon launching clinical trials of the compound to examine its ability to reduce viral loads and inflammation in patients with Covid-19 infection.
The trials are adding to the list of ongoing studies of promising repurposed drugs. Sexton noted that over the course of the pandemic, other drug repurposing studies had identified different compounds with potential efficacy against the virus.
“The results seem to be dependent on what cell system is used,” Sexton said.
“But there is an emerging consensus around a subset of drugs, and those are the ones that have the highest priority for clinical translation. We fully expect that the majority of these won’t work in human beings, but we anticipate some will.”
Remarkably, the Michigan study also identified a class of compounds called MEK-inhibitors (methyl ethyl ketone or Butanone), typically prescribed to treat cancer, that appears to worsen Covid-19 infection. The finding sheds light on how the virus spreads among cells.
“People going in for chemotherapy are at risk already due to a lowered immune response. We need to investigate whether some of these drugs worsen disease progression,” said Sexton.
The next step is to use electronic health records to see whether patients on these drugs have worse Covid-19 outcomes.
The work is one of the first major discoveries of the new University of Michigan Center for Drug Repurposing (CDR), which was established in November 2019, just as the pandemic began. The Michigan Institute for Clinical & Health Research (MICHR), with partners across campus, launched the Center to find potential therapeutics for the thousands of human diseases for which there is no treatment.
“Repurposing existing therapeutic interventions in the clinical setting has many advantages that result in significantly less time from discovery to clinical use, including documented safety profiles, reduced regulatory burden, and substantial cost savings,” said George A. Mashour, co-director of Michigan Institute for Clinical and Health Research and founder/executive sponsor of the Center for Drug Repurposing.
(With inputs from ANI)
Edited by Amrita Das and Krishna Kakani