The truth about hydroxychloroquine’s (HCQ’s) efficacy as a prophylactic/administered-in-response drug against Covid-19 has become a casualty of conflicting reports. A recent observational study led by a hospital in Italy claims that the anti-malarial drug reduced the risk of death amongst hospitalised Covid-19 patients by 30%.
The study involves 3,451 patients treated in 33 hospitals in the country. The researchers claim to have evaluated efficacy in various sub-groups of patients, after taking into consideration all-confounding factors into play. The study, however, isn’t a randomised control trial (RCT)—the gold standard—and the journal it is published in doesn’t have a high impact factor. But, the merits of the impact factor or RCTs/observational studies aside, the question is: Is HCQ of any use in the Covid-19 fight? A clutch of studies say it isn’t; RCTs from China, the US and Canada, Spain, Brazil and the UK (the Oxford RECOVERY trials that established the efficacy of dexamethasone), among others, found that HCQ/HCQ+ regimes didn’t have any significant positive effect over a placebo or usual care. In fact, the chance of ‘adverse events’ were higher. Yet, the Indian Council of Medical Research (ICMR) hasn’t revised it advisory on limited administration of HCQ as a prophylactic, even though earlier this month, the UP government ordered the replacement of HCQ, as a preventative and for treatment, with ivermectin. The National Institutes of Health in the US, too, halted its trial of HCQ in June.
ICMR and other government-affiliated researchers had published the findings of an observational study in the Indian Journal of Medical Research (IJMR) to claim that HCQ was effective, in combination with wearing of PPE, in staving off SARS-CoV-2 infection in health workers. The study couldn’t clearly state whether PPEs and other external factors had a greater role to play in protecting against Covid-19 than HCQ. But, it reported a much lower proportion of Covid-19 cases among those who received HCQ for the longest duration (six weeks) than among those who received it for 4-5 weeks and three weeks. It is important to consider the questions raised by some researchers—including some doctors at AIIMS Delhi and AIIMS Raipur—over the methodology of the study. It is equally important to consider the claims, as reported by The Print, that HCQ trials have come under much greater scrutiny while risks associated with remdesivir, manufactured by the US pharma major Gilead, seem to be getting played down. Given India is a major HCQ producer, it would be tempting to probe for a possible agenda. But the more effective, and scientifically convincing, way to settle questions over HCQ’s efficacy, and in the process tackle any agenda, would be for ICMR to conduct thorough RCTs and make the findings public. One way or the other, the truth about HCQ could finally be agreed upon then.