72 hours. From symptom onset. The antiviral treatment window for covid. There’s a study, overlooked by almost everyone, that shows this.

Title: “Hydroxychloroquine / azithromycin in COVID-19: The association between time to treatment and case fatality rate”

Abstract: “A total of 1265 COVID-19 patients with an average age of 44.5 years were studied…41% with at least one comorbidity…No patient treated within the first 72 h of illness died.” [not a small study and included about 500 high risk patients]

Conclusion: “The case fatality rate in COVID-19 outpatients treated with hydroxychloroquine/azithromycin was associated with the number of days of illness on which treatment was started. ” Yes, hydroxychloroquine works. But the treatment window is narrow. HCQ has to be used on ambulatory patients with mild disease.

Let’s have a look at what the FDA said about using HCQ for covid when it retracted the EUA for hydroxychloroquine…

“Hospitalized patients were likely to have greater prospect of benefit (compared to ambulatory patients with mild illness)….”

So the FDA ignores the fact that hospitalized patients were first “ambulatory patients with mild illness,” but the disease progressed because the patients weren’t treated with an antiviral in a timely fashion. The FDA’s rationalization is “the hospitalized patients are so much sicker and really, really need help.” But it’s clear from the data that early antiviral treatment of ambulatory patients with mild covid is necessary to prevent progression in the high risk patients.

But we can excuse the FDA for not knowing that early treatment was necessary, right? This idea is brand new and we learned about it in 2021 from the Accinelli study, right?

Not necessarily. It was known that “high-risk outpatients” should be treated “promptly” with antivirals “without waiting for laboratory confirmation.”

The CDC said, in Jan. 2020, “Because influenza activity is elevated and both influenza A and B virus infections can cause severe disease and death, this health advisory also serves as a reminder that early treatment with antiviral medications improves outcomes in patients with influenza. Early treatment with antiviral medications is recommended for hospitalized patients and high-risk outpatients, including children younger than two years. Clinicians should…promptly start antiviral treatment of severely ill and high-risk patients with suspected influenza without waiting for laboratory confirmation.” If this is the case for influenza, it was likely the case for covid as well, both being respiratory diseases with short viral incubation periods.

One wonders why the CDC didn’t weigh in on the FDA statement displayed above….

But how can doctors profit from this knowledge? How can they get their patients treated within the 72 hour window after symptom onset? GPs (Family Medicine and other primary care physicians who see outpatients) can follow this list:

1. Make a list of the high-risk patients of the practice.
2. Have your office call the patients and inform them of the 72 hour treatment window.
3. Send out mailings about the 72 hour treatment window for covid antivirals to all patients. Ask them to spread the word to their family and friends.
4. Emphasize that patients are not to wait for lab tests to schedule an appointment, but to call within a day after symptoms begin.
5. Treat with antivirals based on clinical suspicion.

Continuing, what are the implications for studies of treating covid patients late with hydroxychloroquine?

They are worthless. Even if they are RCTs. Retrospective studies that look at early treatment with HCQ have weight, while prospective studies that look at treatment after the 72 hour window do not have weight.

All of the weight is on the side of early treatment with HCQ showing benefit.