When Pfizer Inc. said last month it expects to ship half the Covid-19 vaccines it had originally planned for this year, the decision highlighted the challenges drug makers face in rapidly building supply chains to meet the high demand.
“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 still expects to roll out more than a billion doses in 2021 as originally planned.
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 emergency-use authorization for the vaccine, becoming the first Western country to start administering doses.