Stocks Plunge After Pfizer Cuts Vaccine Rollout Target By Half Due To "Supply Chain Obstacles" Tyler Durden Thu, 12/03/2020 - 15:46 US stocks tumbled during the final hour of trading Thursday as Pfizer revealed that it expects to ship half the number of vaccines this year, raising new questions about the optimistic projections and expectations for the pace of vaccinations. The company cited ambiguous supply chain delays likely tied to the fact that the vaccine needs to be stored at a temperature that's colder than the north pole. "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.