Coronavirus USA: When could Pfizer's vaccine start shipping?

Pfizer's RNA-based Covid-19 vaccine candidate BNT162b2 - which is being developed in partnership with BioNTech, will enter a new stage of advancement as it is now ready for large-scale, Phase 3 human trials. On Saturday, Pfizer announced that they have submitted an amended protocol to the U.S. Food and Drug Administration (FDA) to expand enrollment of their Phase 3 Covid-19 vaccine trial to up to 44,000 participants. The company expects to reach its initial target of up to 30,000 participants this week. Pre-screened volunteers aged from 16 to 85, including people with chronic, stable HIV (human immunodeficiency viruses), Hepatitis C, or Hepatitis B infection will be taking part in these Phase 3 trials.

FDA regulatory review of Covid-19 vaccines

Once a candidate vaccine passes the Phase 3 trial stage and developers are satisfied that the drug is safe, effective and the benefits of using it far outweigh the negative aspects, only then can it be licensed by the FDA. The FDA is the National Regulatory Authority (NRA) in the United States responsible for assuring quality, safety, and effectiveness of all human medical products, including vaccines for human use. Authority for the regulation of vaccines resides in Section 351 of the Public Health Service Act and specific sections of the Federal Food, Drug, and Cosmetic Act (FD&C).

A recent, 15-year study into clinical trial success rates published in Oxford Academic’s Biostatistics journal, compiled data from hundreds of thousands of sponsored industry and non-industry trials and found that candidate vaccines have a 33.4% chance of making it through phase-by-phase clinical trials and to regulatory approval.

If the results of BNT162b2 Phase 3 trials are successful, Pfizer and BioNTech will be on track to seek regulatory review of their vaccine as early as October 2020. If regulatory authorization or approval from the FDA is obtained, Pfizer / BioNTech plan to supply up to 100 million doses worldwide by the end of this year and approximately 1.3 billion doses by the end of 2021.

Pfizer vaccine results to be known by October 

In an interview with CBS’ Face the Nation programme on Sunday, Pfizer CEO Albert Bourla said that they are confident of knowing whether their BNT162b2 vaccine is effective by next month. “In the best case, we have quite a good chance –more than 60% but we will know if the product works or not by the end of October. That doesn’t mean that it works, it means we will know if it works”.

Bourla added that Phase 3 trials will include a wide range of participants, including more age groups and ethnic groups. “The study has recruited very quickly - volunteers from all over the country have raised their hands to participate so we are almost done with 30,000 people. Now we feel quite comfortable with the safety of the product so we want to expand to more vulnerable people, for example to younger people. Until now, the recruits ranged from 18 to 85, now we will go from 16 years old. Also involved will be people with special conditions, chronic conditions like AIDS/HIV patients. We will also use to it to increase the diversity of the population. Globally, only 60% (of participants) are Caucasians, 40% approximately minorities; also, 44% are older people. We try of course to increase it, particularly an emphasis on African-Americans and Latinos.”

The Pfizer CEO underlined a positive message that an effective Covid-19 vaccine is near. “I don’t know if people will have to wait until 2021 because, as I said, with our studies, we have a good chance that we will know if the product works by the end of October and of course, it is the regulators’ job to issue a license or not. I cannot say what the FDA will do, but I think is a likely scenario and we are preparing for it, for example, we have already started manufacturing and we have already manufactured hundreds of thousands of doses, so just in case we have a good study readout, conclusive and the FDA, plus the advisory committee feels comfortable, but we will be ready,” Bourla concluded.