LONDON (Reuters) - The head of Britain’s medicines regulator, asked whether the COVID-19 vaccine rollout risked being disrupted if Britain and the European Union fail to reach a trade deal before the end of the Brexit transition period, said “we are ready”. “We’ve practised, we are ready, we are fully prepared for any possible outcome,” said June Raine, head of the Medicines and Healthcare products Regulatory Agency (MHRA), on BBC television. The MHRA approved the Pfizer vaccine against COVID-19 on Dec. 2 and rollout is scheduled to begin in the coming days. The Brexit transition period ends on Dec. 31.