Summary :
- The first treatment for COVID-19 in young children has been approved by the US Food and Drug Administration. In this situation, the FDA increased the use of Gilead Sciences’ antiviral treatment Veklury (remdesivir) to children aged 28 days and up who weigh at least 3 kilos (about 7 pounds).
- The medication is licenced for children who have tested positive for COVID-19, are hospitalised, or are at high risk of developing severe COVID-19, hospitalisation, or death.
After meeting the primary endpoint in a clinical trial funded by the US National Institute of Allergy and Infectious Diseases, Veklury became the first medicine to be approved by the FDA against COVID-19 in May 2020. (NIAID). In October 2020, it received final approval.
The drug has some controversies, mostly around perceived efficacy. In October 2020, the WHO Reported that the drug didn’t have any particular effect on a patient’s survival based on the WHO’s Solidarity trial. This trial evaluated remdesivir and three other drugs in 11,266 hospitalized COVID-19 patients and found none of them “substantially affected mortality” or decreased the need for ventilation.
About Veklury
Veklury is an antiviral medicine used to treat coronavirus disease 2019 (COVID-19). It is used in adults and adolescents (from 12 years of age and weighing at least 40 kilograms) with pneumonia requiring supplemental oxygen (low- or high-flow oxygen or other non-invasive ventilation at the start of treatment).
The medicine can also be used in adults who do not require supplemental oxygen and who are at increased risk of developing severe COVID-19.
Active Pharmaceutical Ingredient – Remdesivir.
Medical Use:
- In the European Union, remdesivir is indicated for the treatment of coronavirus disease 2019 (COVID‑19) in adults and adolescents (aged twelve years and older with body weight at least 40 kilograms (88 lb)) with pneumonia requiring supplemental oxygen
- In the United States, remdesivir is indicated for use in adults and adolescents (aged twelve years and older with body weight at least 40 kilograms (88 lb)) for the treatment of COVID‑19 requiring hospitalization
- In November 2020, the FDA issued an emergency use authorization (EUA) for the combination of baricitinib with remdesivir, for the treatment of suspected or laboratory confirmed COVID‑19 in hospitalized people two years of age or older requiring supplemental oxygen, invasive mechanical ventilation, or extracorporeal membrane oxygenation (ECMO)
Mechanism of Action :
VEKLURY® (remdesivir) acts to inhibit the SARS-CoV-2 RNA-dependent RNA polymerase (RdRp), which is essential for viral replication—and thus creation of virions that circulate in the body.
Remdesivir enters cells before being cleaved to its monophosphate form through the action of either carboxylesterase 1 or cathepsin A; it is subsequently phosphorylated by undescribed kinases to yield its active triphosphate form remdesivir triphosphate (RDV-TP or GS-443902). RDV-TP is efficiently incorporated by the SARS-CoV-2 RdRp complex, with a 3.65-fold selectivity for RDV-TP over endogenous ATP. Unlike some nucleoside analogues, remdesivir provides a free 3′-hydroxyl group that allows for continued chain elongation. However, modelling and in vitro experiments suggest that at i + 4 (corresponding to the position for the incorporation of the fourth nucleotide following RDV-TP incorporation), the 1′-cyano group of remdesivir sterically clashes with Ser-861 of the RdRp, preventing further enzyme translocation and terminating replication at position i + 3. This mechanism was essentially identical between SARS-CoV, SARS-CoV-2, and MERS-CoV, and genomic comparisons reveal that Ser-861 is conserved across alpha-, beta-, and deltacoronaviruses, suggesting remdesivir may possess broad antiviral activity
Protein binding : Remdesivir is 88-93.6% bound to human plasma proteins while its metabolites GS- 441524 and GS-704277 are 2% and 1% bound, respectively.
Prior to this amendment, Veklury was only approved to treat certain adults and pediatric patients 12 years of age and older who weighed at least 50 kilograms (about 88 pounds) with COVID-19.
“As COVID-19 can cause severe illness in children, some of whom do not currently have a vaccination option, there continues to be a need for safe and effective COVID-19 treatment options for this population,” Dr. Patrizia Cavazzoni, MD, director of the FDA’s Center for Drug Evaluation and Research said. “Today’s approval of the first COVID-19 therapeutic for this population demonstrates the agency’s commitment to that need.”
The FDA is quick to remind everyone that Veklury is not a substitute for vaccination, which is still the best way to prevent or decrease the severity of COVID-19.
The amended authorization was based on efficacy data from Phase III trials in adults. It is also based on Phase II/III trial data of 53 pediatric patients at least 28 days of age who weighed at least 3 kilograms with confirmed COVID-19 infection and mild, moderate or severe COVID-19. These patients received Veklury for up to 10 days. The safety and pharmacokinetic data from the Phase II/III study in children were similar to that observed in adults.
“This approval means that remdesivir can potentially provide meaningful clinical improvement, by reducing disease progression and helping children recover from COVID-19 more quickly,” Dr. Amina Ahmed, MD, Atrium Health-Levine Children’s Hospital in Charlotte, North Carolina said in a statement. “We need proven antiviral treatment options, like remdesivir, that can help treat some of the most vulnerable in our society: children.”