Documents show minimal data supported FDA’s authorization of malaria drugs for COVID-19
FDA’s Emergency Use Authorization for chloroquine and hydroxychloroquine was based on “minimal data,” an agency review document released as result of a Freedom of Information Act lawsuit filed by BuzzFeed News indicates. The review is the most complete official documentation of FDA’s decision to grant an EUA. It does not address allegations of political pressure raised by former BARDA Director Rick Bright (see “Hydroxychloroquine Testing Hahn’s, FDA’s Independence”).
The review emphasizes the need for controlled trials and spells out the known and suspected risks posed by the drugs. It does not indicate how or why FDA determined that the potential benefits outweigh the known risks.
FDA’s risk-benefit assessment notes that the drugs “have been shown to have in vitro activity against SARS-CoV-2 at drug concentrations achievable by doses considered safe in humans.” It adds, however, that “chloroquine has been found to have in vitro activity against numerous viruses, but historically in vivo findings have been less promising.”
The document summarizes known toxicities of the drugs, as well as speculation that the “immune modulating effects of chloroquine and hydroxychloroquine could prove to be detrimental in patients with COVID-19.”
Summarizing clinical efficacy data, the agency’s review noted: “Minimal data are available to date, though a brief report from a Chinese study of 100 COVID-19 patients reported clinical improvement with chloroquine or hydroxychloroquine treatment versus an unspecified control.” The review also stated that while the authors concluded that the study showed “positive preliminary outcomes,” the abstract “reports very similar outcomes in patients randomized to hydroxychloroquine or control.”
It added that a “recent survey by French researchers involving 20 COVID-19 patients, hydroxychloroquine alone and in combination with azithromycin was reported to be associated with viral load reduction over 6 days. The viral load changes were statistically significant compared to a nonrandomized control group and were more pronounced in patients who received the combination.”
The document stresses the need for clinical trials while also recommending an EUA that grants access outside of trials. “The effectiveness of chloroquine and hydroxychloroquine for the treatment of COVID-19 is not yet supported by robust clinical evidence. There is a clear need for continuation and expansion of well-designed clinical trials. However, in settings where clinical trials are not available or not feasible, access to these drugs may be of value in treating COVID-19.”