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Remdesivir Clinical Trials

The remdesivir clinical trial program was designed to answer multiple scientific questions in parallel, to rapidly evaluate the potential for remdesivir to treat COVID-19 patients.

Gilead “SIMPLE” Trials
Gilead is conducting two randomized, open-label, multicenter, Phase 3 clinical studies to evaluate the safety and efficacy of two dosing durations – 5 days and 10 days – of remdesivir in adults diagnosed with COVID-19.

The first of the two SIMPLE studies evaluated the safety and efficacy of both 5-day and 10-day dosing durations of remdesivir, in patients with severe COVID-19. The study initially enrolled 400 patients and subsequently allowed for the enrollment of 5,600 additional patients, including those on mechanical ventilation, in an expansion phase of the study. Topline results from the initial study phase were announced on April 29, and the full results from the initial phase were published in The New England Journal of Medicine on May 27. Data from the expansion phase of the study are expected in the near future.

The second SIMPLE study is evaluating the safety and efficacy of 5-day and 10-day dosing regimens of remdesivir, compared with standard of care alone, in patients with moderate COVID-19. This study initially enrolled 600 patients and subsequently allowed for the enrollment of 1,000 additional patients in an expansion phase of the study. Topline results from the initial study phase were announced on June 1.

Pediatric Trial 
Gilead is conducting a Phase 2/3 clinical trial that will investigate the use of remdesivir in treating pediatric patients with COVID-19. The study will evaluate the safety, tolerability, pharmacokinetics and efficacy of remdesivir in a younger population hospitalized with the virus, including newborns through adolescents. The single-arm, open-label study will enroll approximately 50 patients under the age of 18, beginning in June. Patients will be treated for up to 10 days, with dosing determined based on age and weight. 

REMDACTA Trial
Gilead is working in collaboration with Roche to evaluate the safety and efficacy of remdesivir in combination with tocilizumab, an anti-inflammatory drug, compared to remdesivir plus placebo in patients with severe COVID-19 pneumonia. The Phase 3, double-blind, placebo-controlled trial is expected to begin enrolling in June, with a target of approximately 450 patients globally.

Other Trials
The U.S. National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health, conducted a Phase 2 adaptive, randomized, double-blind, placebo-controlled trial evaluating remdesivir as a potential treatment for hospitalized adult patients diagnosed with COVID-19. Gilead provided study drug at no charge and provided input on study design and conduct. The study enrolled 1,063 participants at 47 U.S. and 21 international sites. Preliminary findings were announced on April 29 and the full data were published in The New England Journal of Medicine on May 22.

NIAID is conducting a second adaptive trial with remdesivir. The Phase 3, double-blind, randomized, controlled trial is evaluating the safety and efficacy of remdesivir in combination with the anti-inflammatory drug baricitinib compared to remdesivir alone. The study initiated in May and is expected to enroll more than 1,000 patients at approximately 100 U.S. and international sites. 

The World Health Organization is conducting an adaptive, randomized, open-label, multi-center clinical trial of the safety and efficacy of remdesivir and three other investigational treatments. Gilead is providing study drug at no charge and provided input on study design and conduct.

Additionally, Inserm in France is conducting a European study evaluating remdesivir and other potential treatments, using a master protocol developed by WHO. Gilead is providing study drug at no charge and provided input on study design and conduct.

Health authorities in China conducted two clinical trials in Hubei province, coordinated by the China-Japan Friendship Hospital, to determine the safety and efficacy of remdesivir in patients with severe and moderate disease. The two studies were stopped early due to low enrollment. Gilead provided study drug at no charge and provided input on study design and conduct.

Additional information on the ongoing remdesivir clinical studies is accessible at the following links: