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]