Pfizer Inc. expects to ship half of the Covid-19 vaccines it originally planned for this year because of supply-chain problems, but still expects to roll out more than a billion doses in 2021. “Scaling up the raw material supply chain took longer than expected,” a company spokeswoman said. “And it’s important to highlight that the outcome of the clinical trial was somewhat later than the initial projection.” Pfizer and Germany-based partner BioNTech SE had hoped to roll out 100 million vaccines world-wide by the end of this year, a plan that has now been reduced to 50 million. The U.K. on Wednesday granted ... (full story)