On August 12, Pfizer and the German firm BioNTech announced interim results from a combined Phase 1/2 trial of their COVID-19 candidate, the mRNA vaccine BNT162b1. As reported in The Indian Express, the vaccine induces a “robust” immune response in healthy subjects aged 18-55. BNT162b1, “elicits an immune response by mimicking the mRNA molecule used by the novel coronavirus SARS-CoV-2 to build its infectious proteins.” Such vaccines are generally considered safe. Some participants had mild to moderate side effects such as fatigue, headache, or fever. They found that the “robust” response was substantially increased with higher doses and with a second dose. SARS-CoV-2 antibodies were present in patients 21 days a single vaccination, with a substantial increase in antibodies seven days after a second dosage. Neutralizing antibodies “were 1.9 to 4.6 times higher,” then in recovering COVID-19 patients who did not get the vaccine. While the data is promising, the researchers think Phase 3 trials are needed to determine efficacy. The study was peer-reviewed and published in Nature; it included 45 healthy adults and a placebo-controlled, double-blind protocol.
US News Weighs In
US News and World Report also took a look at Pfizer vaccine story on August 12. They note that mRNA technology is “cutting edge” and that the Nature study is promising. They note that the trial was led by Dr. Judith Absalon of Pfizer. Dr. Amesh Adalja, infectious disease expert and senior Johns Hopkins scholar, says, “The study provides more evidence of mRNA candidate COVID vaccines do induce neutralizing antibodies after two doses.” Adalja said that multiple COVID-19 vaccine candidate uses mRNA technology, and “this suggests they can spark a potent immune response in people.” He went on, “What remains to be seen is what these antibodies translate to when a vaccinated individual is faced with the wild virus,” Adalja said. “Until we see phase 3 clinical data, it is still an extrapolation to understand how effective these vaccines will be in the real world.”
Pfizer/BioNTech Talk Up Nature Study
Pfizer/BioNTech’s press release noted, “The publication of peer-reviewed data from our mRNA-based vaccine development program against SARS-CoV-2 in a world-renowned publication like Nature provides further validation of our rapid progress toward developing a safe and effective potential vaccine to help address this current pandemic,” quoting Kathrin U. Jansen, Ph.D., Head of Vaccine Research & Development for Pfizer. “We are encouraged by the overall advancement of the program and look forward to generating additional data from our ongoing studies,” she also said.Dr. Ugur Sahin, CEO and Co-founder of BioNTech notes, “Since our inception, we have been deeply grounded in science, which makes sharing our data in a peer-reviewed publication like Nature an even more important milestone. The scientific rigor of our approach is fundamental during the current pandemic.” The upcoming Phase 2/3 trial, “is an event-driven trial that is planned to enroll up to 30,000 participants between 18 and 85 years of age.”
What is an mRNA Vaccine?
The European Commission’s Horizon offers a handy primer on mRNA vaccines. First, these are new. If one was approved for COVID-19, “it would be the first of its type.” While traditional vaccines train the body to recognize viral protein which is introduced in vaccination, “mRNA vaccines, in contrast, trick the body into producing some of the viral proteins itself.” The mRNA is “basically like a pre-form of a protein and its (sequence encodes) what the protein is basically made of later on.” To make an mRNA vaccine, researchers create “a synthetic version” of, “the mRNA that a virus uses to build its infectious proteins. This mRNA is delivered into the human body, whose cells read it as instructions to build that viral protein, and therefore create some of the virus’s molecules themselves. These proteins are solitary, so they do not assemble to form a virus. The immune system then detects these viral proteins and starts to produce a defensive response to them.” Also, “They could be more potent and straightforward to produce than traditional vaccines.” It is unknown “whether there are any downsides” to mRNA.
Horizon goes on, “Most of what we know about mRNA vaccines comes from work on cancer.” Tumor mRNA has been used to assist patients’ immune systems to respond to the proteins from their specific tumor. This works because every tumor is different, so the intervention is targeted. Next, they discuss the “unknowns.” First, it is unknown “whether these vaccines will really be able to mount a sufficiently protective immune response,” in humans. Also, “how long any immunity would last,” and whether the right protein have been chosen are unknown. mRNA shines when it comes to manufacturing; it might take a few months to produce large amounts of vaccine versus one to two years for a traditional technology.
A Cautionary Note
The Independent offered some caution about mRNA tech in a May article about Moderna. Noting that this is “completely new and revolutionary to say the least,” they go on to note that mRNA, “uses a sequence of genetic RNA material produced in a lab that, when injected into your body, must invade your cells and hijack your cells’ protein-making machinery called ribosomes to produce the viral components that subsequently train your immune system to fight the virus. In this case, Moderna’s mRNA-1273 is programmed to make your cells produce the coronavirus’ infamous spike protein that gives the virus its crown-like appearance (“corona” is crown in Latin) for which it is named.”
The vaccine acts almost like an RNA virus, except that it, “hijacks your cells to produce the parts of the virus, like the spike protein, rather than the whole virus.” And some of the mRNA vaccines are “self-amplifying” in that they can, “force the cell to replicate more copies of it.” Opining that it might be hard to convince “conspiracy theorists and anti-vaxxers” that this is not a man-made virus, they go on to state that, “public acceptance of this new paradigm is not something to be easily dismissed nor taken for granted. There are unique and unknown risks to messenger RNA vaccines, including the possibility that they generate strong type I interferon responses that could lead to inflammation and autoimmune conditions.”