In the wake of the corona pandemic, the results were eagerly awaited – now they are here: Two clinical studies on the antiviral active ingredient remdesivir have shown that although this agent is less effective against Covid-19 than hoped, it nevertheless shows slightly positive effects. Accordingly, patients treated with remdesivir recover a few days earlier and the death rate is reduced by a few percent. Remdesivir thus does not appear to be the miracle cure for Covid-19, as it was temporarily traded in advance. Still, it could save at least some patients.
So far, there is no cure for the Covid-19 disease caused by the Sars-CoV-2 coronavirus. Physicians can only provide supportive treatment to patients with severe courses who develop pneumonia and acute shortness of breath. But they have nothing against the virus raging in the body. Accordingly, researchers around the world are looking feverishly for agents that could help against Sars-CoV-2. One of the promising candidates is the antiviral drug Remdesivir from the US pharmaceutical company Gilead. Remdesivir originally developed it against the Ebola virus, but it was not very effective against it. For this, this agent can inhibit the multiplication of Sars and Mers viruses closely related to Sars-CoV-2, as animal experiments had shown. The antiviral effect of Remdesivir is based on its function as a so-called nucleotide analog. Because its structure resembles RNA building blocks, it is erroneously incorporated into the genome strains of the new virus copies during virus replication. This blocks the completion of the viral RNA and thus prevents functional new viruses from emerging.
Faster recovery, slightly lower death rate
To test the potential of remdesivir against Covid-19, two larger phase III clinical studies started in February 2002 – one was carried out with 237 patients in several clinics in Wuhan, but then had to be stopped due to the lack of further Covid-19 cases. The other included 1,063 patients in 47 clinics in the United States and 21 other centers in Europe and Asia. Both studies are so-called randomized double-blind studies: Neither patients nor treating doctors knew who received a placebo and who received the active substance in the daily injections. This type of clinical study is regarded as the “gold standard” in medicine because the results are largely avoided due to expectations being distorted. Both studies administered remdesivir to patients with severe courses from about ten days after the onset of symptoms.
The first results for these studies are now available to the highest standards. The Wuhan team has already published their data in the specialist journal “The Lancet”, a peer-reviewed publication is still pending for the US study, there is only information from the National Institute of Allergy and Infectious Diseases (NIAID) that commissioned the study . In both studies, remdesivir was reported to have a slightly positive effect. Accordingly, the patients recovered a few days faster with the agent than with placebo – in China it was 18 versus 23 days, in the United States it was 11 days versus 15 days in the placebo group. In China, however, these differences were not enough to be statistically significant, but in the United States. There were also slight but insignificant effects on the death rates: in China, remdesivir killed me 11 percent of the patients, in the placebo group it was 15 percent. In the United States, the death rate for patients treated with the drug was eight percent; with placebo, 11.6 percent of those infected with Covid 19 died.
Muffled hope
This makes it clear that remdesivir is not the miracle cure for Covid-19 that many had previously hoped for. “These data are promising given that we have no proven drug against Covid-19 yet,” said Babak Javid of Tsinghua University in Beijing. “But the data also show that remdesivir is not the magic bullet.” Bin Cao, a co-author of the China study from Beijing Medical University, sees it similarly: “This is not the result we were hoping for. Remdesivir was found to be safe and well tolerated, but the advantages over the placebo were not significant. ”Anthony Fauci, head of the National Institute of Allergy and Infectious Diseases, assessed the results in a press conference significantly more positively. He believes that the effects of remdesivir are sufficient to make it a standard treatment for Covis 19 patients in the future. “The data show that remdesivir has a clear, significantly positive effect on the time to recovery,” said Fauci.
The reactions of many scientists are somewhat more cautious. At best, you see a start in these two studies. “This is far from the end of the history of remdesivir,” said Saad Shakir of the British drug safety research unit in Southampton. “Other studies on this are already ongoing and we will have to wait and see what results they bring.” According to some virologists, remdesivir may have been so weak in these studies because it was given relatively late in the course of the disease. At this point, it is primarily the body’s immune response that causes the serious symptoms. Therefore, Remdesivir could be more effective if given earlier – for example, in the first week after the onset of symptoms. However, it is usually not clear at this point in time which course the disease will take. This makes it difficult to determine whether the remedy or nature itself has prevented a difficult course. In addition, remdesivir must be administered by injection and is relatively expensive. It is therefore still unclear whether and in what form Remdesivir will actually be used against Covid-19 in the future. According to the clinical database Cliniclatrials.gov, there are currently five other large studies with this active ingredient.
Source: National Institute of Allergy and Infectious Diseases (NIAID); Yeming Wang (National Clinical Research Center for Respiratory Diseases, Beijing) et al., The Lancet, doi: 10.1016 / S0140-6736 (20) 31022-9