Clinical trial data:
Remdesivir was rapidly pushed through clinical trials during the West African Ebola virus epidemic of 2013–2016. As the preliminary results were promising; it was used in the emergency period of the Kivu Ebola epidemic in 2018. But it was found less effective than monoclonal antibody treatments such as mAb114 and REGN-EB3. The trials, however, established the safety profile of the drug.[11] In Phase II clinical trials as anti-Ebola drugs, the fatality rate in remdesivir group was 53% which was not significantly less than average 50% fatality rate of the disease itself and significantly worse than that of the two monoclonal antibodies MAb114 (fatality rate 35%) and REGN-EB3 (fatality rate 33%).[12]
A nurse from Scotland with Ebola meningoencephalitis was successfully treated with high dose corticosteroids and 14 days of remdesivir therapy (once-daily infusion of 150 mg over 2 h for 2 days followed by daily 225 mg for another 12 days).[13]
A randomised, double-blind, placebo-controlled, multicentre trial at ten hospitals in Hubei, China was conducted recently, recruiting adult patients of laboratory-confirmed SARS-CoV-2 infection with prefixed inclusion criteria. Patients were randomly assigned in a 2:1 ratio to intravenous remdesivir (200 mg on day 1 followed by 100 mg on days 2–10 in single daily infusions) or the same volume of placebo infusions for 10 days along with concomitant therapy of lopinavir–ritonavir, interferons, and corticosteroids. Though the study was limited by insufficient power to detect assumed differences in clinical outcomes and late starting of therapy, Remdesivir failed to prove statistically significant clinical improvement.[14] Few COVID-19 patients from United States were treated with Remdesivir and showed clinical improvement. On 17 March 2020, the drug was provisionally approved to be used amongCOVID‑19 patients due to serious outbreak in the Czech Republic. On April 29 2020, Gilead Sciences, Inc. announced results from the open-label, Phase 3 SIMPLE trial evaluating 5-day and 10-day dosing durations of remdesivir in hospitalized patients with severe manifestations of COVID-19 disease. The study demonstrated that patients receiving a 10-day treatment course of remdesivir achieved similar improvement in clinical status compared with those taking a 5-day treatment course (Odds Ratio: 0.75 [95% CI 0.51 – 1.12] on Day 14). No new safety signals were identified with remdesivir across either treatment group. More than half of patients in both treatment groups were discharged from the hospital by Day 14 with 64.5% of patients in the 5-day treatment group and 53.8% of patients in the 10-day treatment group achieved clinical recovery. In an exploratory analysis, patients in the study who received remdesivir within 10 days of symptom onset had improved outcomes compared with those treated after more than 10 days of symptoms. Pooling data across treatment arms, by Day 14, 62% of patients treated early were able to be discharged from the hospital, compared with 49% of patients who were treated late.[15]
On 1 May 2020, the U.S. Food and Drug Administration issued an emergency use authorization for the investigational antiviral drug remdesivir for the treatment of suspected or laboratory-confirmed COVID-19 in adults and children hospitalized with severe disease..[16]