The scientist behind the BioNTech/Pfizer coronavirus vaccine has defended his company from Donald Trump’s accusation that it deliberately delayed news of its rapid progress until after the election, saying “we don’t play politics”. BioNTech, a German company, and the US pharmaceutical giant Pfizer announced on Monday that their jointly developed vaccine candidate had exceeded expectations in the crucial phase 3 vaccine trials, proving 90% effective in protecting people from coronavirus infections. The US president criticised the timing of their press release. Trump accused the companies of holding back the good news until after the American elections “because they didn’t have the courage to do it before”. But BioNTech’s chief executive, Prof Uğur Şahin, told the Guardian in a wide-ranging interview he only was notified of the outcome of the interim trials on Sunday at 8pm in a call from the Pfizer CEO Albert Bourla, who himself had only been informed three minutes earlier by the independent monitoring board. “We want to develop this vaccine as quickly as possible, and we have our own system of coordinates,” Şahin said in response to Trump’s accusation. “Every day counts, and we were desperately waiting for the day of the trial results. It couldn’t come early enough.” “Pharmaceutical research should never be politicised. It’s a question of integrity. Withholding information would have been unethical. What’s important for us is that we are developing a vaccine and we don’t play politics.” Others have criticised the two companies for not holding on to their information long enough. Bourla raised eyebrows when he sold $5.6m (£4.2m) in stock as company shares soared on Monday night. Pfizer says the shares were sold via an automated system after they hit a certain price, under a plan set up in August.