Remdesivir Shows Early Clinical COVID-19 Improvement in Phase 3 Trial

This is an ongoing story and will be updated with further information as it develops.

Gilead Sciences has released topline results from an open-label, phase 3 clinical trial comparing five-day and 10-day dosing of its investigational antiviral remdesivir for patients hospitalized with severe coronavirus disease 2019 (COVID-19).

The SIMPLE trial appears to have demonstrated that patients receiving the five-day dose duration achieved similar improvement (odds ratio [OR], 0.75; 95% CI, 0.51—1.12 on Day 14) in clinical status compared to patients who received the 10-day dosing duration.

Ramifications could be significant, given the treatment of some patients with a five-day dose duration might expand the global stock of remdesivir substantially.

“These study results complement data from the placebo-controlled study of remdesivir conducted by the National Institute for Allergy and Infectious Diseases and help to determine the optimal duration of treatment with remdesivir," Merdad Parsey, MD, PhD, Chief Medical Officer for Gilead Sciences, said in a statement. "This is particularly important in the setting of a pandemic, to help hospitals and healthcare workers treat more patients in urgent need of care."

There are not currently any licensed or approved treatments for COVID-19 globally, and it remains to be proven by further study whether remdesivir is safe or effective for treatment of COVID-19. There were no new discoveries in terms of remdesivir’s safety profile during the trial. Clinical improvement was defined as an improvement of ≥2 points from baseline on a predefined seven-point scale.

To be eligible for the study, patients needed to show evidence of pneumonia and reduced oxygen levels that did not require mechanical ventilation at the time of study entry. Patients were considered to have achieved clinical recovery if they no longer were discharged from the hospital or no longer required oxygen support and medical care.

In the trial, time to clinical improvement for 50% of patients was 10 days in the 5-day treatment group and 11 days in the 10-day treatment group. Over half of patients in both treatment groups were discharged from the hospital by Day 14 (five-day, 60.0% vs.10-day, 52.3%; P = .14).

At Day 14, 64.5% (n = 129) of patients in the 5-day treatment group and 53.8% (n = 106) of patients in the 10-day treatment group achieved clinical recovery. Early treatment was also substantial, in terms of clinical outcome.

Participants who received remdesivir within 10 days of symptom onset had improved outcomes relative to those treated after over 10 days of symptoms. Pooling data across treatment arms, 62% of patients treated within 10 days were able to be discharged from the hospital, compared with 49% of patients who were treated late.

“While additional data are still needed, these results help to bring a clearer understanding of how treatment with remdesivir may be optimized, if proven safe and effective,” Aruna Subramanian, MD, Clinical Professor of Medicine at Stanford University School of Medicine and a lead investigator of the study, said.

The SIMPLE studies are 2 randomized, open-label, multi-center phase 3 clinical trials conducted in countries with high prevalence of COVID-19 infection.

The first SIMPLE trial focused on comparing five-day and 10-day dosing durations for patients with severe COVID-19 at 180 trial sites worldwide. The study has now been expanded to include an additional 5600 patients, including participants who are on mechanical ventilation.

The second SIMPLE trial is evaluating the safety and efficacy of 5-day and 10-day dosing durations of remdesivir administered intravenously in patients with moderate COVID-19, compared with standard of care. The results from the initial 600 patients of this trial are anticipated at the end of May.

There is also a trial of remdesivir underway at the University of Nebraska Medical Center, sponsored by the National Institute of Allergy and Infectious Diseases, which is a part of the National Institutes of Health.

The Nebraska study is a randomized, controlled clinical trial to evaluate the safety and efficacy of remdesivir in hospitalized adults with COVID-19.

Anthony Fauci, MD, director of the National Institutes of Allergy and Infectious Diseases, said Wednesday that the National Institutes of Health trial was likely to herald "quite good news" and called remdesivir a "drug that can block this virus."