Analysts warn against 'pretty picture' painted by Gilead's coronavirus treatment

Gilead’s (GILD) promising antiviral treatment is fanning optimism in the increasingly uphill battle against the coronavirus pandemic, and sparking a market rally.

Yet some analysts have cautioned investors to curb their enthusiasm over the drug, called remdesivir, and the potential for it to be effective on a broader scale. Late Thursday, Gilead’s shares spiked — sending stock futures on a tear — after a leaked report published by medical news publication STAT revealed that a group of COVID-19 patients in Chicago saw “rapid recoveries” and eased symptoms.

Those results mirrored what Gilead had already published in a study of its own on April 10, when it reported positive results in 53 patients via a New England Journal of Medicine article. The company is expected to provide full clinical trial results by the end of the month, around the time Gilead reports quarterly earnings.

“We cannot draw definitive conclusions from these data, but the observations from this group of hospitalized patients who received remdesivir are hopeful," said Jonathan Grein, Director of Hospital Epidemiology at Cedars-Sinai Medical Center in Los Angeles, and lead author of the journal article. “We look forward to the results of controlled clinical trials to potentially validate these findings.”

Both the Chicago and NEJM results lack any information about a control arm, which many experts say is key to understanding the effectiveness of the drug — something that Wall Street analysts took pains to point out on Friday.

“While the article paints a pretty picture, we think the ensuing exuberance shows a lack of critical analysis,” analysts at Baird Equity Research wrote.

“This is uncontrolled, anecdotal data, which often winds up not being confirmed in controlled studies,” the firm added, referencing the controversy over hydroxychloroquine, an anti-malarial drug that’s also shown effectiveness against the coronavirus in isolated instances.

The company originally applied for orphan drug status, but rescinded it after backlash. In addition, the drug was first reported to have positive results in China, but the company struggled to recruit participants for clinical trials there.

"While this data...is yet another anecdotal case along with the compassionate use cohort, we still need to see the data as well as controlled trials," analysts at SunTrust said on Friday.

Remdisivir’s clinical trial results will inform the Food and Drug Administration’s (FDA) decision to approve the drug for broader market use.

Given the severity of the coronavirus outbreak, remdisivir has seen a lot of hopes pinned on it — with investors bullish on Gilead’s stock and closely watching updates. President Donald Trump has also touted the drug’s potential in daily coronavirus briefings, pointing to it among the many clinical trials for therapeutics currently under way.

The company’s own CEO has remained cautious, in an open letter Daniel Day emphasized, “In studying remdesivir, the question is not just whether it is safe and effective against COVID-19 but in which patients it shows activity, how long should they receive treatment and at what stage of their disease would treatment be most beneficial. Many answers are needed, which is why we need multiple types of studies involving many types of patients.”

Gilead has said it has 1.5 million individual doses, or enough to treat 140,000 patients, ready for use once approved by the FDA, and is working to produce enough for 1 million patients by the end of the year.

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Anjalee Khemlani is a reporter at Yahoo Finance. Follow her on Twitter: @AnjKhem

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