Coronavirus diary – Part 34
The two most powerful warriors are patience and time. – Leo Tolstoy
Time is the wisest counselor of all. – Pericles.
This installment focuses on the vaccine question in greater detail than previous references. It is news that many of the vaccine candidates have now completed their Phase 3 clinical trials. Pfizer, Moderna, and Oxford candidates, namely, BNT162b2, mRNA-1273, and AZD1222 have breasted the tape in the race for an effective COVID-19 vaccine. I begin with the question: what are vaccines? Vaccines are clinical formulations that cure or inhibit viruses in our system through the acceleration of the response of our body soldiers. Aaron Steckelberg, Senior graphics editor, Washington Post, states that “Vaccines work by teaching the body’s immune system to recognize and block viruses. Each category of vaccine technology works under this basic principle. Vaccines aim to activate the immune system’s T-helper cells, which are responsible for detecting the presence of a virus. They instruct B-cells to create antibodies that block the virus from being able to replicate and T-killer cells to destroy infected cells. Some vaccines may activate only part of this immune response.”
According to Aaron Steckelberg, there are 190-plus vaccines in the pre-clinical stage being tested in animals and lab experiments. In Phase 1, 15 vaccines are being tested in a small number of healthy, young people for safety and proper dose measurement. In Phase 2, 15 vaccines are extended to a larger group of people, including people that are prone to ill-health. In Phase 3, 10 vaccines are being tested in thousands of people for efficacy and safety. And none has been approved on a balance sheet of benefits and risks. Steckelberg went further to note that “Vaccine development usually takes years and unfolds step by step. Experimental vaccine candidates are created in the laboratory and tested in animals before moving into progressively larger human clinical trials…These steps are now overlapping in the race to find a vaccine for a global disease that has killed hundreds of thousands of people. Human testing began in some cases before animal studies were finished”.
However, at the beginning of the outbreak of COVID-19, the goal of the scientific community was to produce a vaccine within a year and a half in the race against time. Recall that Vaccines take years to produce and the global quest for HIV vaccine has yet to triumph more than a generation. The drive for a quick vaccine lies in the benefit of technology. In the words of Steckelberg, “Advancements in science and technology have given researchers new tools to try against the coronavirus. Scientists can deliver genetic material into the body’s cells, turning them into vaccine factories and skipping time-consuming steps such as manufacturing viral proteins or growing the whole virus in chicken eggs.”
It is important to note that there are a variety of vaccines, and they include vaccines using nucleic acid (DNA and RNA); viral-vectored vaccines; subunit vaccines; and weakened or inactivated virus vaccines. I shall focus mainly on the DNA and RNA types being developed by Moderna, Pfizer, and BioNTech among others. According to Steckelberg, “DNA vaccines contain genetic material that carries the blueprint for the spike protein. To get the DNA into cells, researchers use an electrical pulse to disrupt the cell membrane. Once inside, the DNA is used as a template to create spike protein.” On the other hand, “RNA vaccines contain a strip of genetic material within a fat bubble. Once inside the cell, the RNA generates a protein found on the surface of the virus. The immune system, presented with the protein, learns to recognize the virus.” Steckelberg supplies a caveat to note: “These vaccines have the advantage of speed — they can be quickly designed and manufactured. But they have never been approved for use outside of medical research and will likely require two doses.”
Not long ago, the seeming hopelessness on a solution to COVID-19, forced Anthony Fauci to conclude with scary morbidity to the extent that humans would have to live with COVID-19 like other ailments such as HIV/AIDS. The US elections foregrounded the vaccine question. For Trump, the hope was on Johnson and Johnson and ‘Operation Wasp Speed’ had been compacted for seamless distribution.
While President Trump was speculating on a vaccine breakthrough before yuletide, Pfizer and Moderna have come to validate his timing. From a joke, it has morphed into reality. On November 9, 2020, Pfizer and BioNTech announced the consummation of Phase 3, COVID-19 vaccine candidate fulfilling all “primary efficacy endpoints”. On November 16, Moderna released news of his successful clinical trials, and on November 23, the Oxford-AstraZeneca group announced a breakthrough with its vaccine candidate.
The Pfizer vaccine, BNT162b2 presents the following results: “Primary efficacy analysis demonstrates BNT162b2 to be 95% effective against COVID-19 beginning 28 days after the first dose; 170 confirmed cases of COVID-19 were evaluated, with 162 observed in the placebo group versus 8 in the vaccine group….Efficacy was consistent across age, gender, race and ethnicity demographics; observed efficacy in adults over 65 years of age was over 94%….Safety data milestone required by U.S. Food and Drug Administration (FDA) for Emergency Use Authorization (EUA) has been achieved”.
On the side effect, “Data demonstrate vaccine was well tolerated across all populations with over 43,000 participants enrolled; no serious safety concerns observed; the only Grade 3 adverse event greater than 2% in frequency was fatigue at 3.8% and headache at 2.0%”.
While the companies plan to submit within days to the FDA for EUA and share data with other regulatory agencies around the globe”, they have also panned out its production global benchmark of 50 million vaccine doses in 2020 and about 1.3 billion doses by the end of 2021. But this process is intricate. The vaccine requires a temperature of about -70 degrees Celsius that presents its corresponding problem of storage and distribution. Pfizer hopes that its existing cold-chain infrastructure that includes the use of dry ice and a GPS-enabled thermal sensor that tracks location and temperature could aid world-wide distribution of the vaccine.
The Moderna announced that its vaccine is 94.5% effective against coronavirus. A highly enthused Dr. Anthony Fauci, the infectious disease expert exclaimed, “It’s just as good as it gets — 94.5% is truly outstanding.” It is based on messenger RNA technology that has yet to be approved for human use. Like the Pfizer counterpart, The Moderna vaccine has to be stored frozen at minus-20 degrees Celsius.
The Oxford/AstraZeneca vaccine called AZD1222 or ChAdOx1 nCoV-19 is viral vectored made from a weakened version of a common cold virus that causes infections in chimpanzees. Its efficacy averaged 70 percent from ongoing clinical trials. As Steckelberg has pointed out, people can develop immunity in ways that could require a booster shot. Unlike the Pfizer and Moderna vaccine, the Oxford-AstraZeneca vaccine does not present storage problem and therefore logistically flexible. AstraZeneca’s chief executive Pascal Soriot, the vaccine will cost $2.50 a dose while that of Moderna and Pfizer will cost between $15 and $25 a dose.
NB: This analysis will be continued in Part 35 of this serial.
Professor Akhaine is a Professor of Political Science at the Lagos State University.
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