PrEP Medications May be Potential COVID-19 Treatments

Widely used medications for patients with HIV and AIDS may be potential treatments for the coronavirus disease 2019 (COVID-19) should the drugs demonstrate safety and efficacy in clinical trials, according to experts.

David Hardy, adjunct professor of medicine for the Division of Infectious Diseases at Johns Hopkins University School of Medicine, told the Washington Blade that if early promising results from clinical trials hold for remdesivir, and emtricitabine and tenofovir combination therapy (Truvada, Gilead Sciences) could be shown to be effective since the 2 drugs are in the same family of medications.¹

Remdesivir is an investigational broad-spectrum antiviral treatment. The drug is currently being rushed to patients with infections from the novel coronavirus in the hopes that it can reduce the intensity and duration of COVID-19 and ease the burden of the pandemic on health systems. Additionally, the drug is now being tested in 5 COVID-19 clinical trials and has been delivered through a compassionate use program to some patients, including the first case of COVID-19 in the United States.²

The first trial results for remdesivir are expected next month, although a paper released through a preprint server without peer review citing the epidemiology, clinical course, and viral characteristics of the first 12 US patients with COVID-19 includes information on 3 participants who were treated with the drug. In this study, analysts with the CDC raised concerns about a lack of evidence emerging from a small number of study participants.³

According to experts, there was not a “clear temporal association” between treating patients with remdesivir and improvements in oxygen requirements, fever, and viral results, compared with patients who were hospitalized and did not receive the investigational drug. They also noted that remdesivir patients experienced adverse events, including nausea, vomiting, rectal bleeding, and elevated liver enzymes.³

Contrastingly, a study published in February in the National Institutes of Health’s Proceedings of the National Academy of Sciences suggested that remdesivir inhibited the replication of Middle East respiratory syndrome (MERS), a related coronavirus, in infected monkeys. MERS-CoV is closely related to COVID-19. ^4,5

According to Hardy, remdesivir and Truvada, both developed by Gilead Sciences, work by the same mechanism of action that targets the virus in its replication cycle. “I would wager to say that if the clinical studies that are studying remdesivir in China and then in the [United States] now show some promise, then there’s gonna be a very quick look at Truvada to see if it works,” Hardy told the Washington Blade.¹

Truvada is a combination therapy of 2 antiretroviral medications, emtricitabine and tenofovir. Both prevent HIV from replicating, and while they work in different ways, each blocks the reverse transcriptase enzyme needed for reproduction. A key difference between the drugs is that Truvada can be administered orally, whereas remdesivir requires intravenous injection.^6,7

Hardy warned that despite reports that HIV medications may be effective against the coronavirus, patients taking the drugs either for prevention or treatment of the disease may still be susceptible to COVID-19 and able to transmit it.¹

The Sichuan Academy of Medical Sciences and Sichuan Provincial People’s Hospital are conducting the clinical trial for Truvada against COVID-19.⁶ Additionally, remdesivir is being assessed in multiple clinical trials globally in order to evaluate its safety and efficacy in COVID-19.³

Reference

• PrEP may be tested against coronavirus if antivirals shown to work. The Washington Blade. Published March 24, 2020. https://www.washingtonblade.com/2020/03/24/prep-may-be-tested-against-coronavirus-if-hiv-meds-shown-to-work/. Accessed April 7, 2020.
• NIH clinical trial of remdesivir to treat COVID-19 begins. National Institute of Health. Published February 25, 2020. https://www.nih.gov/news-events/news-releases/nih-clinical-trial-remdesivir-treat-covid-19-begins. Accessed April 7, 2020.
• Silverman, Ed. A new paper about a Gilead drug to combat coronavirus has some analysts skittish about success. STAT. Published March 13, 2020. https://www.statnews.com/pharmalot/2020/03/13/gilead-coronavirus-covid19-clinical-trials/. Accessed April 7, 2020.
• Remdesivir prevents MERS coronavirus disease in monkeys. National Institutes of Health. Published February 13, 2020. https://www.nih.gov/news-events/news-releases/remdesivir-prevents-mers-coronavirus-disease-monkeys. Accessed April 7, 2020.
• Cronin, Jacqueline, Feldmann, Friederike, de Wit, Emmie et al. Prophylactic and therapeutic remdesivir (GS-5734) treatment in the rhesus macaque model of MERS-CoV infection. PNAS.org. Published February 7, 2020. https://www.pnas.org/content/pnas/early/2020/02/12/1922083117.full.pdf. Accessed April 7, 2020.
• McGrath, Jenny. All the COVID-19 vaccines and treatments currently in clinical trials. Digital Trends. Published April 2, 2020. https://www.digitaltrends.com/health-fitness/coronavirus-covid-19-vaccines-treatments-list/. Accessed April 7, 2020.
• Landscape analysis of therapeutics. WHO. Published March 21, 2020. https://www.who.int/blueprint/priority-diseases/key-action/Table_of_therapeutics_Appendix_17022020.pdf?ua=1. Accessed April 7, 2020.
• Joseph, Andrew. As the coronavirus spreads, a drug that once raised the world’s hopes is given a second shot. STAT. Published March 16, 2020. https://www.statnews.com/2020/03/16/remdesivir-surges-ahead-against-coronavirus/. Accessed April 7, 2020.