The combination of vacuolin-1 and apilimod is expected to fight SARS-CoV-2

In a recent study, researchers from Boston Children’s Hospital, Harvard Medical School and Washington University in St. Louis found that two drugs inhibited SARS-CoV-2, which causes COVID-19, in human cell tests. Both of these two drugs, vaccine-1 and apilimod, developed years ago, target a large enzyme called PIKfyve kinase. Previously, little was known about the role of this enzyme in SARS-CoV-2 infection. The relevant research results were recently published in PNAS.

The co-corresponding author of the paper, Dr. Tomas Kirchhausen of the Cellular and Molecular Medicine Project of Boston Children’s Hospital, said, “Our findings show that targeting this kinase through a small-molecule antiviral against SARS-CoV-2 may be an effective strategy to lessen the progression or seriousness of COVID-19.”

Early research shows that vacuolin-1 and apilimod are effective against Ebola virus

When Kirchhausen discovered vacuolin-1 16 years ago, he and his colleagues at the Center for Excellence in Translational Research of Harvard Medical School began a long-term study of small molecules against emerging viruses. They found that both vacuolin-1 and apilimod, which are chemically similar, are effective inhibitors against Ebola virus, but they did not publish their findings at the time.

Vacuolin-1 and apilimod can also prevent SARS-CoV-2 virus infection

Kirchhausen and Dr. Sean Whelan at the University of Washington conducted cell biology research with the SARS-CoV-2 virus. Kirchhausen said, “Within a week, we knew that apilimod was very effective in preventing SARS-CoV-2 from infecting human cells in the laboratory.” In April 2020, he first published this discovery on the BioRxiv pre-print website. Kirchhausen added, “We found that, like apilimod, vacuolin-1 is also a very strong inhibitor of viral infection in the laboratory.”

Apilimod is now used in COVID-19 clinical trials

Currently, AI Therapeutics has obtained FDA approval to study aripipimod against COVID-19 to see whether it can reduce the severity of the disease. In late July this year, AI Therapeutics announced the use of apilimod to carry out a new clinical study that will test the safety, tolerability and effectiveness of apilimod in reducing the amount of virus in patients with early-onset COVID-19 disease.


1. Alice McCarthy,“Two drugs join forces against COVID-19” (2020).