. . The World Health Organization has advised that Remdesivir, one of the drugs that Donald Trump took when he developed Covid-19, should not be used in hospitals because there is no evidence of its effectiveness.. . The US president was an ardent supporter of the drug, so much so that in July he boasted that he had bought up the entire world's stock for Americans.. However, the WHO's guideline committee said that Covid patients may be better off without it. The. . .