Shares of Gilead Sciences Inc. were dented April 23 after reports surfaced that its antiviral drug, remdesivir, failed to improve the condition of patients with COVID-19. The Foster City, Calif.-based company, however, said the data, which were published accidentally by the World Health Organization (WHO) and reported by the Financial Times, represented “inappropriate characterizations” of the China study.

The information has since been removed from the WHO website, said Merdad Parsey, chief medical officer at Gilead, who also pointed out that “study was terminated early due to low enrollment and, as a result, it was underpowered to enable statistically meaningful conclusions. As such, the study results are inconclusive, though trends in the data suggest a potential benefit for remdesivir, particularly among patients treated early in disease.”

Gilead said data were submitted for peer-reviewed publication.

Two phase III studies in China testing remdesivir in patients with COVID-19 infection were halted last week after Chinese authorities reported a lack of eligible patients. Other studies, including trials sponsored by the Foster City, Calif.-based company, remain ongoing. Promising – though limited – compassionate use data were published earlier this month in The New England Journal of Medicine from a cohort analysis of 53 severe patients hospitalized with severe complications from COVID-19 who showed a cumulative incidence of clinical improvement of 84% after 28 days of follow-up, according to Kaplan-Meier analysis.

Remdesivir, which targets RNA-dependent RNA polymerase, was identified early on as a possible treatment against SARS-CoV-2, the coronavirus that causes COVID-19. A paper published Jan. 31 in NEJM suggested the drug, previously developed for use against Ebola virus, might prove effective in patients diagnosed with COVID-19.

Ongoing trials include a phase III parallel-assignment study, anticipated to enroll 2,400 patients, 12 and older, with severe COVID-19 at 152 sites worldwide. The study will test two regimens of remdesivir, measuring the odds of ratio for improvement on a seven-point ordinal scale at day 14 as the primary endpoint. Another phase III study is enrolling 1,600 patients, 12 and older, testing remdesivir vs. standard of care, using the same endpoint.

Remdesivir also is being administered to patients under compassionate use protocols and is included in the WHO’s Solidarity study aimed at testing a variety of potential treatments in patients with COVID-19 infection.

“There are multiple ongoing phase III studies that are designed to provide the additional data needed to determine the potential for remdesivir as a treatment for COVID-19,” Parsey said. “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.”

Shares of Gilead (NASDAQ:GILD) closed April 23 at $77.78, down 4.3%.