Gilead drug shows promise, but wait for more rigorous trials
Given that the Covid-19 spread has claimed close to 150,000 lives so far—over 33,000 deaths are in the US alone—governments and the masses alike are desperately latching on to any hint of a pharmacological breakthrough. Indeed, the US president, in a White House press briefing in March, had called two antimalarials and an antiviral, Gilead Sciences’s remdesivir, “game-changers”. The US drug regulator then had to put out a statement clarifying that it was adopting a far more cautious outlook, pending rigorous trials. Against such a backdrop, pharma companies are training their focus on research on combatting Covid-19—vaccines, antivirals, even biologics, etc—and, predictably, there has been a rally in the stocks of such companies. Indeed, the Nifty Pharma Index has jumped by 32% between March 16 and April 16.
Hydroxychloroquine (HCQ), a cheap, generic antimalarial used over many decades, was believed to have some impact on controlling Covid-19—anecdotal evidence, correlations such as low reported incidence in countries with a heavy malarial burden, even trials and studies that weren’t peer-reviewed were used to talk up the drug, resulting in the clamour in policy circles globally to procure these drugs for their population growing manifold.
So much so that the US tried to armtwist India, the world’s largest producer of HCQ, into withdrawing a ban on the drug’s export, while the Brazilian president likened it to sanjibani booti from the Ramayana. But, a spate of studies have questioned the role HCQ can play in the current pandemic. Though there is no conclusive evidence yet to say that HCQ doesn’t work at all, the frenzy around it certainly would have driven up the stocks of the companies making it, which, in turn, would have made people believe more fervently that a cure is in sight.
A similar euphoria is getting built around unofficial results from the University of Chicago Medicine indicating some relief in Covid-19 symptoms in patients who were given remdesivir—this was developed by Gilead during the Ebola outbreak, and was tested among patients in Africa to limited success. Perhaps, remdesivir—which interferes with the replication of the SARS-CoV-2 RNA in the host cell, causing premature termination—can help with Covid-19, but, this must be established through studies that conform to sound testing methods. The UChicago trial, apart from Gilead’s own, is without controls that would help establish the drug’s efficacy with reasonable certainty. As an analysis by equity research concern, Baird, puts it, “randomized, controlled data” could “refute previously ‘encouraging’ data from small, uncontrolled studies”.
The world will have better understanding of remdesivir’s action in late-May, when the US’s National Institute of Allergy and Infectious Diseases publishes the results of its double-blind, placebo-controlled study. Also, the success, in terms of the low mortality observed in the UChicago sample, could be because of the strict restriction on the kind of cases included in the trial—cases of Covid-19 requiring mechanical breathing support, showing signs of organ failure, etc, were not included.
That said, hopes of a cure will be more well-founded as more research comes out, especially on de novo interventions like the two vaccine candidates already being tested—one in the US, and one in China. India, too, has a stake in all this, with two companies—Serum Institute of India, and Zydus Cadilla—in the vaccine race.