Over the past six months pharmaceutical companies have made various predictions about their Covid-19 vaccine timelines that have turned out not to be true.
In one recent example, Pfizer has said repeatedly it would know by the end of October if its vaccine works or not – but Tuesday on an investor call, the company’s CEO essentially ruled that out.
Scientists say that should guide us as we move closer to having a vaccine: Don’t believe everything you hear, because testing and manufacturing vaccines are notoriously unpredictable.
“Unexpected things happen all the time in vaccine development,” said Dr. Nelson Michael, an Army vaccine specialist who has worked on more than 20 vaccine clinical trials.
“There are tons of twists and turns, and it’s important to understand that.”
In May, University of Oxford researchers predicted they would have data from their clinical trials by September at the latest, but that did not happen. Their clinical trial is still underway.
While at times Pfizer, Oxford and other vaccine developers have couched their statements, at other times, they have been more definitive about their timelines.
There are 45 candidate vaccines currently at the clinical evaluation stage of development and 156 in preclinical evaluation, according to the World Health Organization.