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Filomeno Sta. Ana III

DEFENDING SINOVAC AND ASTRAZENECA



Good old pal Melo posted on his Facebook account: “I was scheduled for vaccination today. When I found out na Sinovac, I declined.”


Our common friend Mike reacted and said: “I totally disagree with your decision my friend.” In response, Melo cited the e-mail letter he sent to his mayora wherein he cited his reasons for declining the vaccine. First, the Director of the Chinese Center of Disease Control says that the efficacy of China’s vaccines is low. Second, the publication of peer-reviewed data on Sinovac is not available. Third, the Sinovac manufacturer has a record of bribery.


Melo’s reasons are already familiar to me. In mid-January 2021, a journalist friend conducted a straw poll about Sinovac among the University of the Philippines activists during the early years of martial law (the martial law babies). The question that he asked: “Who among us will be willing to have a Sinovac vaccination? Yes or No.”


All those who joined the straw poll — more than a dozen — responded “No.”  The reasons are similar to those that Melo enumerated. To summarize, the criticisms revolve around efficacy, transparency, pricing, and corruption. We will return to these issues later.


Of course, these are but anecdotes. But surely, such fear or apprehension causes concern because it can affect efforts to convince the general public to be vaccinated. Note that the people involved in the anecdotes are highly educated and highly articulate.  (Melo also claims to be handsome, and I believe him.)


In other words, this is the class that has the ability to sway public opinion in favor of vaccination. Only when the significant majority of adult Filipinos are vaccinated can society attain herd immunity.


Sadly, the majority of our people are hesitant to be vaccinated. The Pulse Asia survey conducted from Feb. 22 to March 3 shows that only 16% of the respondents are willing to take the vaccine. In the same vein, 61% of the respondents do not want to be vaccinated. The main reason behind the hesitation is safety, probably arising from the dengvaxia vaccination strategy. (See Scott B. Halstead, “Dengvaxia: Knowns and unknowns, March 21, 2021, BusinessWorld.)


And among the small number of respondents willing to be vaccinated, only 21% of them choose the Sinovac vaccine.  But AstraZeneca fares worse, getting favor only from 6% of those willing to be vaccinated. (Pfizer is the preferred choice of 52% of those willing to be vaccinated.) AstraZeneca has also suffered from a perception that is unsafe. Rare blood clots, which can be lethal, have occurred in relation to the AstraZeneca and Johnson and Johnson vaccines.


These issues can set back our vaccination effort since the currently available vaccines for the Philippines are Sinovac and AstraZeneca. In light of these issues, it is imperative to answer the questions that cast doubt on the available vaccines in the country.


We thus tackle squarely the issues confronting Sinovac as well as AstraZeneca.


Our principal concern should be about safety and efficacy or effectiveness. The term “efficacy” is used during clinical trials (or randomized controlled trials) to measure the degree to which a vaccine can prevent COVID-19 infection. The term “effectiveness” is used in measuring the degree to which the same vaccine will prevent transmission in real world conditions.


In this regard, the history of bribery becomes extraneous so long as the evidence on the COVID-19 vaccines’ safety and efficacy (or effectiveness) is incontrovertible. The paramount consideration is whether the vaccine makers “stand with science.”


Morality, however, matters when a manufacturer is found to be guilty of fraud or corruption in the making of the COVID-19 vaccine. So far, the regulators worldwide have shown competence in approving emergency use authorization for COVID-19 vaccines based on stringent safety and efficacy standards.


Besides, raising a past issue of bribery or corruption is a slippery slope argument. If we would use a company’s history of corruption as a barrier to accepting COVID-19 vaccines, we would probably end up having insufficient vaccines. A Google search of corruption involving big pharma will yield undesirable results for corporations like Pfizer, Johnson and Johnson, and AstraZeneca.


Moderna, a startup, has likewise been embroiled in controversy. According to National Public Radio (NPR), an “examination of official company disclosures has revealed additional irregularities and potential warning signs.” (See Tom Dreisbach, “Bad Optics’ Or Something More? Moderna’s Executives’ Stock Sales Raise Concerns,” Sept. 4, 2020.)


The issue of supposed overpricing of Sinovac vaccines in the Philippines is now a dead issue. The allegation: The Philippine price for Sinovac was significantly higher than the prices found in other emerging market economies.


But it turned out that the so-called Philippine price was obtained from information on the Web. It was a hypothetical price since no agreement had taken place then. The actual price was derived from the negotiations. Ultimately, the Sinovac price that the Philippines has secured is aligned with prices of other countries.


The next issue is about information. Here, it does not help that China’s system is opaque. But the information to make sound decisions on Sinovac is actually available. The Lancet, a leading peer-reviewed journal and the world’s oldest general medical journal, published Sinovac’s randomized, double-blind, placebo-controlled Phase One and Two clinical trials on Nov. 17, 2020.


Just recently, SSRN (formerly known as Social Science Research Network) posted on April 14 an article on Sinovac’s Phase Three clinical trial among health professionals in Brazil. The efficacy results are as follows: 50.7% against symptomatic COVID-19, 83.7% against moderate cases, and 100% against severe cases.


Old pal Melo and others are concerned over the 50.7% rate against symptomatic COVID-19. They argue that this rate is low in comparison to the efficacy rates of Pfizer and Moderna.

Two important points counter the said argument. The first point is that the principal objective of getting vaccinated is to prevent severe or critical cases and deaths. On this score, the Sinovac vaccine performs well.


The second point is that comparing the efficacy rates of different vaccines is like comparing apples and oranges. Confounding variables make comparisons difficult. Take the case of Sinovac’s clinical trial in Brazil. The trial happened at a time of high virus transmission in a country most overwhelmed by the pandemic. Moreover, the participants in the trial were very vulnerable health workers.  This combination of factors tended to yield a lower primary efficacy rate.


The latest information on Sinovac comes from Chile, which, like Brazil, has been hard hit by the COVID-19 surge. But this time, the study applies to real world conditions. Chile is one of the leading countries that have high inoculation rates for COVID-19. Sinovac supplies around 60% of Chile’s total vaccines. Chile’s real world investigation covers 10.5 million people, observing both those who had been vaccinated and those who had not.


The real world study shows that the Sinovac vaccine is 67% effective in preventing symptomatic infections, 85% effective in preventing hospitalizations, and 80% effective in preventing deaths. According to Reuters, the study’s authors stressed that “a lower protection against death than in clinical trials, should be considered against the backdrop of a fierce second wave.”


Before the release of this real world study, the media highlighted a frank statement from Gao Fu, the Director of the Chinese Center for Disease Control and Prevention that “current vaccines don’t have very high protection rates.”


Some looked at his statement as a confirmation of the inferior quality of the Chinese vaccines. But Gao Fu said that his statement was completely misunderstood. In an exclusive interview with China’s The Global Times, he said that his statement was to offer a “scientific vision” towards improving the vaccine’s efficacy.


We should in fact welcome Gao Fu’s statement. Science is about humility, experimentation, and improvement. In fact, what he said is quite similar to the statement of Pfizer’s Chief Executive Officer (CEO), Albert Bourla. Mr. Bourla recently announced the likelihood that people who have taken the Pfizer vaccine will need a booster shot. He also suggested the possibility of a yearly Pfizer re-vaccination.


Another point raised by my friend Melo is that instead of taking Sinovac, he’d rather wait for the arrival of a vaccine with a higher efficacy rate. The statement from Pfizer’s CEO should give him and others pause.


Furthermore, the experts have cautioned against this approach of waiting for a vaccine with higher effectiveness. In a paper titled “The Benefits of Vaccinating With the First Available COVID-19 Coronavirus Vaccine” in the American Journal of Preventive Medicine, in January this year, authors Sarah Bartsch, Kelly O’Shea, et al., share their findings:


“Except for a limited number of situations mainly early on in a pandemic and for a vaccine that prevents infection, when an initial vaccine is available, waiting for a vaccine with a higher efficacy results in additional hospitalizations and costs over the course of the pandemic.”


Finally, we turn our attention to AstraZeneca. Worldwide, the confidence of governments and people in AstraZeneca has suffered as a result of findings that the vaccine is associated with blood clots. Some governments have restricted the use of AstraZeneca to older people. Denmark, lately, stopped the AstraZeneca rollout.


Yet, we must give weight to an Oxford University paper authored by Maxime Taquet, Masud Husain, et al., titled “Cerebral venous thrombosis: a retrospective cohort study of 513,284 confirmed COVID-19 cases and a comparison with 489,871 people receiving a COVID-19 mRNA vaccine” (undated). The relevant findings are:


• The likelihood of developing a blood clot from COVID-19 tremendously increases beyond the risks related to vaccination.

• The odds of getting a blood clot are five in a million for those vaccinated with AstraZeneca.

• The odds of having a blood clot are four in a million for those vaccinated with Pfizer and Moderna.

• But the risk of blood clotting resulting from COVID-19 is eight to 10 times more than reported for vaccines.


Thus, even as vaccination may increase the odds of getting a blood clot (four or five in a million), the odds are still extremely low. Moreover, having a vaccination has to be weighed against the bigger risks associated with COVID-19, including much bigger chances of developing clotting.


Ultimately, each one of us has to balance the benefits and the costs. Based on the information that is available, the benefits from being vaccinated soonest, regardless of vaccine brand, enormously outweigh the risks associated with vaccination. 


Filomeno S. Sta. Ana III coordinates the Action for Economic Reforms.


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