Downing Street tried to get doses of the Oxford University/AstraZeneca coronavirus vaccine labelled with an image of the union jack, it has emerged, as scientists and statisticians raised more questions over the press release that proclaimed the trial’s success. The request for injection kits to bear the flag was driven by No 10’s newly formed “Union unit”, which is tasked with combating calls for Scottish independence and other campaigns to break up the UK. Whitehall sources confirmed the request, which was first reported in the Huffington Post. It was ultimately rejected and Boris Johnson’s spokesman said there were no plans to put a flag on the vaccine kits. Despite the union jack revelation, the Department of Health maintains it had nothing to do with the timing of the Oxford/AstraZeneca announcement on Monday, and said the government had kept well away from the process. A Whitehall source admitted questions had been asked about the presentation of the Oxford vaccine and subsequent criticism in the media. “Of course this is an important vaccine for us, so there are concerns. But the government cannot get involved in any way.” Asked why it appears to have been reasonable to attempt to interfere in the packaging on the vaccine but not the product, the source said: “There is a line which the government cannot cross, and the packaging is it.” Concerns over a press release announcing the vaccine, from the pharmaceutical company AstraZeneca, emerged within days of its release. Experts said it could seed public doubt despite the drug being tested and scrutinised by regulators before being made available. AstraZeneca said it planned to conduct an additional global trial to assess initial results showing 70% efficacy overall and a 90% rate among a smaller number of under-55s who received a lower initial dose, initially by mistake. Some details of the 90% efficacy regime were not disclosed in the press release. A full paper setting out results is expected to be published in the Lancet within days. “Press releases are there for the stock market, they are not there for the science,” said Stephen Evans, a professor of pharmacoepidemiology at the London School of Hygiene & Tropical Medicine. Such releases are requirements for publicly traded companies. “We have to live with it – it’s the stock market rules, and I wouldn’t jump up and down about it. But it is really unfortunate.” He said he trusted the UK’s medical regulator, the Medicines and Healthcare products Regulatory Agency (MHRA), to assess the vaccine fully. AstraZeneca has said its trials “were conducted to the highest standards”. Menelas Pangalos, the company’s executive vice-president, said “the best way of reflecting the results is in a peer-reviewed scientific journal, not in a newspaper”. A spokesman said: “There is strong merit in continuing to further investigate the half-dose/full dose regimen. We are further evaluating the data and will work with regulators on the best approach for further evaluation.” Dani Prieto-Alhambra, a professor of pharmacoepidemiology at the University of Oxford, said there was a lack of complete data on the vaccine candidates. “We are hearing very strong opinions about this data that just cannot and should not be based on what is there, because we don’t have enough information on any of the three vaccines under discussion so far,” he said. But he added: “There is a danger sensationalism can take us to the wrong place very quickly. This will have an impact on public opinion, but not on regulators.” He criticised the attempt to have union jacks emblazoned on vaccine doses, saying: “I just don’t believe in nationalism in science, and even less so with vaccines. This is something of global, not national, importance.” Stephen Senn, a statistical consultant who has done work for Pfizer and AstraZeneca among many others and has written about the Oxford vaccine’s press release, said the information published was “really confusing” because it combined British and Brazilian trials carried out over a long period during which the expected rate of infection might have changed. He added: “My suspicion is that the statisticians involved wouldn’t have cleared it.” He said that while the study involved more than 11,500 subjects, once the model was corrected to allow for biases resulting from recruiting over a long time period in different countries, the results were as if there had been 4,200 participants – less than 10% of the number in the Pfizer phase 3 trial. “It’s not that a press release is automatically inappropriate,” he said, but added: “The motive of publishing glory is a pretty strong one which is sometimes overlooked.” Liam Smeeth, a professor of clinical epidemiology at the London School of Hygiene and Tropical Medicine, said public trust would have been helped if the announcement had been clearer about the process given the accidental manner in which the half-dose study was carried out. “The western scientific model is that you set out your hypothesis and test it, and that wasn’t this process. With bigger numbers in a pre-planned way, there’s a reasonable chance the effectiveness will be less.” Noting that the Oxford vaccine was still a “fantastic achievement”, which he did not believe had been rushed out, he added: “In an ideal world, you would like the press release to wait until the full peer-reviewed research is also available. I think that would have helped public trust a little bit.”