THE New York Times report on February 25, headlined, “Israel study says Pfizer vaccine is very effective in real-world use”, has resulted in a flurry of similar news reports but with different headlines.
 
Local health professionals also made reference to the news concerning the study by Dagan, Barda, Kepten et al (2021) published on February 24 in the New England Journal of Medicine (NEJM).
 
A detailed analysis of the Dagan and colleagues’ NEJM paper gave a picture quite different from what was reported by the media. It also begs the question if journalists and health professional find it more convenient not to read the full scientific paper.
 
The published paper in NEJM, “BNT162b2 mRNA Covid-19 Vaccine in a Nationwide Mass Vaccination Setting”, has ten authors listed, of whom eight disclosed receiving grants from Pfizer outside the published work.
 
The disclosure forms, not visible to unkeen eyes, appeared as attached documents and were not conspicuously mentioned in the paper proper. There is clear conflict of interest and the individual author’s motivation for the study is in question. Only the vaccine manufacturer would be highly motivated to conduct the study to show efficacy of its product.
 
The study by Dagan and colleagues was a follow-up to an early study by Polack, Thomas, Kitchin et al (2020) on the “Safety and efficacy of the BNT162b2 mRNA Covid-19 vaccine”, also published in the NEJM. Of the 20 authors, only seven had non-disclosure. The others were either employees of Pfizer who received fees or grants. The study was sponsored, financed and paper written by Pfizer.

Members of the data monitoring committee that was supposed to be independent were anonymous and appointed by the study sponsor. Much can be argued about the integrity of scientific research today when it involves corporate interest.

The producer of the vaccine should not conduct the trials, otherwise, it is difficult to be objective. The vaccine manufacturer can design a clinical trial to make a favourable outcome much more likely. Selecting the endpoints, the type of outcome measures, time frame of study, and age group of subjects are good examples.

Furthermore, with conflict of interest through direct and indirect financial ties with study sponsor among those involve in the study, it is difficult to avoid public perception of bias.

In view of the large population in the study group, this retrospective, observational study by Dagan and colleagues could have been better designed to be a single-arm, quantitative and descriptive study of the whole population. The population could serve as its own control, or there is no need for any control.

The absolute figures showing the decline of infective rate as well as the severity of symptoms are more important to inform the effectiveness of the vaccine, rather than figures showing reduced relative risk.

In the Israel study, the estimated vaccine effectiveness seven days after the second dose was – for documented infection, 92%; symptomatic illness, 94%; hospitalisation, 87%; and severe disease, 92%. These are relative risk reduction and not absolute risk reduction. The risk difference, which is after subtracting the cumulative incidence of the unvaccinated group with the cumulative incidence in the vaccinated, appears to be narrow.

In a large-scale population study, which follows an experimental study in the form of randomised control trial, what matters most is the absolute figures. The absolute figures of the various outcome measures for the vaccinated group were not mentioned in the main report but found in the graphs and figures.

Of the 596,618 who were vaccinated, after the second vaccine shot at 28 days – documented infection was 4,404 cases (compared to 5,775 unvaccinated); symptomatic Covid-19, 2,373 (3,433); Covid-19 hospitalisation, 108 (244); severe Covid-19, 52 (157); death, 7 (27).

The Israel study objective was to assess Covid-19 vaccine effectiveness based on the original clinical trial. The clinical trial primary endpoint was to assess the vaccine’s ability to lessen the severity of the disease and not to prevent disease or save lives.

As shown in the results of the Israel population study, after 28 days of the vaccine doses and despite the curves having flattened, there were still reports of infection and death. Hence, media reports painting a glossy real-world scenario of the Pfizer vaccine show they have not made their own investigative analysis.

This is mainly a critique of the scientific reports based on research governance, methodology and the manner the results are reported. It does not question the efficacy of the vaccine that has been established. – March 11, 2021.

* Captain Dr Wong Ang Peng is a researcher with an interest in economics, politics, and health issues. He has a burning desire to do anything within his means to promote national harmony. Captain Wong is also a member of the National Patriots Association.