Pre-Exposure Prophylaxis Proposed for COVID-19 Disease

Borrowing from successful HIV/AIDS prophylaxis, researchers have proposed a way to avoid severe COVID-19 disease by rethinking the use of an FDA-approved medication that is cheap and readily available. The proposal was published by the Center for Open Science in OSF Preprints (https://osf.io/tm9r4).
 
The report entitled "Pre-Exposure Prophylaxis with Hydroxychloroquine for COVID-19 Disease” was authored by internist Raphael Stricker and nurse practitioner Melissa Fesler from Union Square Medical Associates in San Francisco, CA. The authors have extensive experience treating patients with tick-borne diseases and recently published a proposal for early treatment of SARS-CoV-2, the viral agent of COVID-19 disease, based on that experience ( https://pubmed.ncbi.nlm.nih.gov/32343423/ ).
 
The proposal for pre-exposure prophylaxis (PrEP) of COVID-19 disease focuses on hydroxychloroquine (HCQ). This controversial antimicrobial agent gained notoriety when it was considered for treatment of severe SARS-CoV-2 infection using high daily doses in combination with azithromycin. The regimen appeared to have antiviral efficacy based on reports from France and the USA, but concerns about cardiac toxicity and retinal damage have limited its use. The fact that HCQ treatment became politicized added to the controversy over its value for SARS-CoV-2 therapy.
 
The new report points out several attractive features of HCQ that were overlooked in the midst of the controversy: HCQ has an extremely long half-life of 40 days in the human body, which makes it an ideal candidate for prophylaxis of viral infection. It has been used for malaria prophylaxis for decades in limited weekly dosing, which avoids the toxicity seen with high daily doses. It is also cheap and readily available if dosing is kept to a minimum.
 
“We realized that HCQ could be safely used to avoid severe viral infection,” says Fesler. “It is the same principle that led to PrEP with much more expensive drugs for HIV/AIDS. We may not be able to avoid infection with this approach, but we hope to limit its severity and transmission.”
 
The researchers pointed to groups at high risk for COVID-19 disease, including healthcare providers, patients with hypertension or diabetes, and the elderly. Weekly PrEP with HCQ should benefit these groups and avoid severe disease. A controlled trial using this approach is now in progress, but the results will not be known for some time. Although feverish work on a protective vaccine continues, a successful vaccine product is nowhere in sight.
 
“We are sending people back to work without any defenses,” says Stricker. “PrEP gives us a practical way to fight the virus and keep everybody safe. What do we have to lose?”

Contact Information

Raphael Stricker

Medical Director

Union Square Medical Associates

(1) 4153991035

rstricker@usmamed.com