By Lily Cao ’22
Staff Writer
Pharmaceutical companies around the world are working to develop vaccines against the novel coronavirus in an effort to alleviate the burdens brought by the global pandemic.
The development of vaccines is a lengthy process. Before a vaccine gets to clinical trials, it must undergo various stages of testing to guarantee its effectiveness. During the preclinical testing stage, the vaccine is given to animals to see whether it elicits an immune response. Once the vaccine has been proven to elicit an immune response in animals, it is administered to a small group of people, then hundreds, then thousands, during Phase 1, 2 and 3 clinical trials, respectively. If the vaccine passes all three trials, regulators then authorize the licensing of the vaccine for public use.
Currently, over 90 COVID-19 vaccines worldwide are in the preclinical testing stage, and 44 are in various phases of clinical trials. However, not every vaccine in development will pass all three trials and arrive at the final approval stage.
The Massachusetts-based biotechnology company Moderna Therapeutics, in collaboration with the National Institutes of Health, has been the frontrunner in coronavirus vaccine development. Its technology is based on injecting viral mRNA into the body. The idea behind this is that the genetic information encoded in the RNA will be translated into protein, subsequently triggering an immune response. Compared to DNA-based vaccines, RNA-based ones are safer, as they pose no risk of altering the person’s natural DNA sequence. RNA vaccines are also less expensive and take less time to produce than traditional vaccines, making them a favorable solution to a rapidly evolving global pandemic like the novel coronavirus.
If Moderna’s candidate gets approved, it would be the first mRNA-based vaccine to be used on humans. Moderna’s vaccine entered Phase 3 of clinical trials on July 27. It will enroll 30,000 participants from across the U.S. in its final round of testing.
Janssen Pharmaceutica of Johnson and Johnson is investigating the non-replicating viral vector vaccine in which a portion of the coronavirus DNA is introduced into the adenovirus vector, which serves as the vehicle to deliver genetic material into the human body and trigger immune responses. The adenovirus is known to cause the common cold; however, when used in vaccines, the virus is genetically modified so that it will not harm the vaccine recipient. The company launched its Phase 3 trial in collaboration with Operation Warp Speed in September, enrolling 60,000 volunteers worldwide.
Maryland-based biotech company Novavax is known for its efforts in combating infectious diseases using innovative vaccines. Its coronavirus vaccine candidate, NVX-CoV2373, was genetically engineered using its recombinant nanoparticle technology to produce the coronavirus spike protein-derived antigen. The candidate contains Novavax’s proprietary saponin-based Matrix-M adjuvant, which has been shown to augment immune responses. The vaccine works by allowing the antibodies generated to block the binding of the spike protein to receptors on human bodies, thereby stopping the virus from infecting and further replicating in the vaccine recipient. Because Novavax’s vaccine development method is based on traditional vaccine technology, some experts argue that its candidate shows promise, since the world has had experience with this vaccine development method before, unlike the mRNA-based vaccines other companies are developing. Novavax’s Phase 3 trial in the U.K. hopes to enroll up to 10,000 participants ranging from 18 to 84 years old.
However, health care officials warn the public that even if the vaccines get approved soon, there is going to be a lag before their distribution. Moreover, not everybody will want to get vaccinated, and not everybody receiving the vaccine will produce an effective immune response. Therefore, people should still take serious safety precautions like washing their hands, keeping socially distanced and wearing masks.
