Another day, another leak—or so it seems for Gilead Sciences' COVID-19 hopeful remdesivir. This time, the World Health Organization (WHO) accidentally revealed data from a study in China showing that the treatment neither improved patients’ condition nor tamped down on the amount of virus in their blood, the Financial Times reported, calling the trial a “flop.”
But was it really a flop? Analysts are saying no.
The study tested remdesivir in 158 patients, comparing their response to 79 patients in a control group. The treatment “was not associated with a difference in time to clinical improvement,” according to draft documents inadvertently published by the WHO that were seen by the FT and Stat and have since been removed. Patients in both study arms experienced side effects at roughly the same rate (about 65%), but more patients on remdesivir stopped treatment early because of side effects compared with placebo (12% versus 5.1%).
As Evercore ISI analyst Umer Raffat pointed out in a note to clients, though, the study allowed patients to start the Gilead candidate up to 12 days after symptoms first appeared. "That is a VERY long window," he wrote, noting that with antivirals for acute infection, "the earlier you start, the better the efficacy."
"For me, the real detail is NOT out yet: efficacy in patients that start early," he said.
Gilead, for its part, also took issue with idea that the trial had failed. “We believe the post included inappropriate characterizations of the study,” said Gilead Chief Medical Officer Merdad Parsey, M.D., Ph.D., in a statement. “The study was terminated early due to low enrollment, and, as a result, it was underpowered to enable statistically meaningful conclusions.”
While the results are inconclusive, though, Gilead did see “trends in the data [that] suggest a potential benefit for remdesivir, particularly among patients treated early in disease,” Parsey said.
Jefferies analyst Michael Yee, meanwhile, also stressed the point that the study ended early because investigators struggled to recruit patients.
“[We] reiterate this was the study out of China that was stopped due to low enrollment and never completed; we've repeatedly said [remdesivir] might be modestly helpful but likely not a magic bullet cure anyway,” Yee wrote in a note Thursday, echoing Gilead's take on the data.
These latest results come one week after leaked data from a Chicago hospital suggested remdesivir quickly reduced fever and respiratory symptoms in patients with severe COVID-19. That site is participating in a Gilead-sponsored phase 3 study that has no comparator arm.
“I think the truth is somewhere in the middle,” Raffat wrote.
There are multiple phase 3 studies underway to gauge how effective remdesivir is in combating SARS-CoV-2, the coronavirus behind COVID-19. In addition to carrying two phase 3 studies, Gilead has made the drug available to studies run by other sponsors, including the one in China, as well as to more than 1,700 people on a compassionate use basis. The National Institute of Allergy and Infectious Diseases is running a study pitting remdesivir against placebo, while Gilead is comparing two remdesivir regimens to standard of care in patients with moderate COVID-19.
“These studies will help inform whom to treat, when to treat and how long to treat with remdesivir. The studies are either fully enrolled for the primary analysis or on track to fully enroll in the near future,” Parsey said.
Gilead was down 4% after the news broke Thursday afternoon, with its shares yo-yoing over the past few weeks on every update, whether leaked, official or stopped, coming out of a remdesivir trial.