Pfizer begins testing vaccine on humans
Firms around the world are racing to develop coronavirus preventative
Pfizer and the German pharmaceutical company BioNTech announced that their potential coronavirus vaccine began human trials in the United States on Monday. If the tests are successful, the vaccine could be ready for emergency use here as early as September.
The two firms are jointly developing a vaccine candidate based on genetic material known as messenger RNA, which carries the instructions for cells to make proteins. By injecting a specially designed messenger RNA into the body, the vaccine could potentially tell cells how to make the spike protein of the coronavirus without actually making a person sick.
Because the virus typically uses this protein as a key to unlock and take over lung cells, the vaccine could train
a healthy immune system to produce antibodies to fight off an infection. The technology also has the advantage of being faster to produce, and tends to be more stable than traditional vaccines, which use weakened virus strains.
Moderna, Inovio, CanSino and several other pharmaceutical
companies are trying similar approaches, some of which began the first phase of tests in humans a few weeks ago. But no vaccine made with this technology for other viruses has ever reached the global market.
Pfizer, which is based in New York, and BioNTech injected the first human volunteers with their vaccine candidate, called BNT162, in Germany last month. The experimental shot was given
to just 12 healthy adults, although the trial will eventually expand to 200 participants.
In the United States, the drug companies plan to test the vaccine on 360 healthy volunteers for the first stage of the study, adding up to 8,000 volunteers by the end of the second stage. The study will be conducted at New York University’s Grossman School of Medicine, the University of Maryland School of Medicine, the University
of Rochester Medical Center and the Cincinnati Children’s Hospital Medical Center.
Participants will be divided into groups to compare four variations of the vaccine, each representing a format of messenger RNA with instructions to make a distinct piece of the spike protein machinery. Doctors will closely monitor the participants’ antibody levels, liver enzymes and other indicators of possible side effects.