The world anxiously awaits a vaccine against the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) disease, which has caused the pandemic of coronavirus disease 2019 (COVID-19).

But vaccine development is not speedy as a candidate moves through the process — exploratory and pre-clinical stages, clinical development (three phases), regulatory review and approval, manufacturing, and quality control. In fact, the U.S. Food and Drug Administration only approved the first vaccine against Ebola virus in 2019, 43 years after the deadly virus was discovered.

In the case of vaccines against COVID-19, pharmaceutical companies are moving at an unprecedented rate with at least 120 projects launched worldwide, involving gene-based vaccines, inactivated vaccines, or live vaccines with viral vectors, to name a few, each touting advantages and disadvantages.

One project is triggering stronger immune responses in recipients than those seen in people naturally recovering from an infection of COVID-19.Pfizer and its German biotech partner, BioNTech, are currently evaluating four different vaccine candidates as part of their BNT162 mRNA-based vaccine program against SARS-CoV-2 in a phase 1/2 placebo-controlled, observer-blinded clinical trial.

This trial evaluated 45 people. Each participant received 10, 30 or 100 microgram doses of the vaccine or a placebo to determine an optimal vaccine dose as well as safety and immunogenicity.

According to BioNTech, testing of two dosages of its BNT162b1 drug on 24 healthy volunteers showed that after 28 days, they had developed higher levels of COVID-19 antibodies than typically seen in patients who have recovered from COVID-19. The higher of the two doses, both administered via two injections within three weeks of one another, was followed by a short fever in three of four participants after the second injection, especially in participants in the highest dose group.

These preliminary data, together with additional preclinical and clinical data, will be used by the two companies to determine a dose level and select among multiple vaccine candidates to move forward to a large, global Phase 2b/3 safety and efficacy trial. That trial may involve up to 30,000 healthy participants and is anticipated to begin in late July 2020, depending on regulatory approval.

According to Ugur Sahin, M.D., CEO and co-founder of BioNTech, thepreliminary data are encouraging, showing that BNT162b1, which exploits the receptor binding domain SARS-CoV-2 as a target antigen, is able to produce neutralizing antibody responses in humans at or above the levels observed in convalescent sera at relatively low dose levels.

According to Kathrin U. Jansen, Ph.D., Senior Vice President and Head of Vaccine Research & Development, Pfizer, in the face of this global health crisis, Pfizer is dedicated to developing potentially groundbreaking vaccines and medicines and looks forward to publishing their clinical data in a peer-reviewed journal as quickly as possible.