But they said the findings support remdesivir as the standard therapy for patients hospitalised with COVID-19, and requiring supplemental oxygen therapy.
"However, given high mortality despite the use of remdesivir, it is clear that treatment with an antiviral drug alone is not likely to be sufficient".
For the time being and due to limited supplies, it will go to those most likely to benefit.
A statement from the Medicines and Healthcare products Regulatory Agency says: "Early results from clinical studies have shown that remdesivir reduced the time of recovery from 15 days to 11 days in patients with severe COVID-19 and possibly also reduced the proportion of people dying from COVID-19".
Similar arrangements have already been made with other countries, including an emergency authorisation from the FDA in the USA and MHLW/PMDA in Japan.
Meanwhile, the World Health Organization (WHO) has chose to suspend dosing of hydroxychloroquine in its SOLIDARITY drug trial after finding an increased risk of death in patients who were given the drug - which President Donald Trump famously says he has been taking prophylactically to ward off coronavirus infection.
Early data suggests it can cut recovery time by about four days, but there is no evidence yet that it will save more lives.
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When the numbers of locusts grow, they become gregarious in habit and stay collectively in dense groups. The federal and state agricultural departments have been using chemical sprays to battle the locusts.
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Vice President Mike Pence visited the state of Georgia, where he had lunch with the governor at a reopened cafe. "It's not right. Thanks to technology, places of worship have been able to find creative ways to meet virtually during the COVID-19 pandemic.
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Although details remain secret, a similar security bill withdrawn in 2003 carried life sentences and drew massive street protests. Beijing's move comes after pro-democracy protests in 2019 plunged Hong Kong into its biggest political crisis since the handover.
"This shows fantastic progress, said Lord James Bethell, Government minister for innovation, adding: "As we navigate this unprecedented period, we must be on the front foot of the latest medical advancements, while always ensuring patient safety remains a top priority".
"The latest, expert scientific advice is at the heart of every decision we make, and we will continue to monitor remdesivir's success in clinical trials across the country to ensure the best results for United Kingdom patients".
The government today (May 26) announced that selected patients with severe Covid-19 will be allowed to be treated with remdesivir.
The scheme, launched by the United Kingdom government in 2014, tries to make certain drugs available for the seriously ill before they have market authorisation.
Dr Stephen Griffin from the University of Leeds Medical School, said it was perhaps the most promising anti-viral for coronavirus so far.
Until now doctors could not prescribe or use remdesivir, outside of trials.
Meanwhile, the World Health Organization (WHO) on Monday announced it is temporarily suspending a global trial evaluating the safety and effectiveness of hydroxychloroquine, citing a study published Friday in the Lancet showing the drug increased the risk of death among patients.