First massive peer-reviewed research study of real-world efficiency of COVID-19 vaccine by Israel’s Clalit Research Institute released in The New England Journal of Medicine.
Major research study, carried out in cooperation with scientists from Harvard University, taken a look at information on 600,000 immunized people in Israel, in addition to 600,000 matched unvaccinated controls.
Two dosages of Pfizer/BioNTech vaccine decreased symptomatic COVID-19 by 94% and extreme illness by 92%; Single dosage decreased symptomatic COVID-19 by 57% and extreme illness by 62%; Vaccine efficiency was discovered to be comparable throughout age; B.1.1.7 alternative ended up being dominant in Israel throughout the research study duration.
The Clalit Research Institute, in cooperation with scientists from Harvard University, evaluated among the world’s biggest incorporated health record databases to analyze the efficiency of the Pfizer vaccine versus COVID-19. The research study supplies the very first massive peer-reviewed examination of the efficiency of a COVID-19 vaccine in an across the country mass-vaccination setting. The research study was carried out in Israel, which presently leads the world in COVID-19 vaccination rates.
The outcomes of this research study validate and enhance the formerly reported findings of the Pfizer/BioNTech Phase-III randomized scientific trial, which concentrated on symptomatic infections, and which, with 21,720 immunized people, might not specifically examine vaccine efficiency versus extreme illness in the completely immunized. The present research study’s plus size permits a more comprehensive evaluation of the vaccine’s efficiency in avoiding a larger series of results, throughout various period and population sub-groups.
The research study happened from December 20, 2020, the launch of Israel’s nationwide vaccination drive to February 1, 2021. It accompanied Israel’s 3rd and biggest wave of coronavirus infection and disease, throughout which the B.1.1.7 alternative slowly ended up being the dominant pressure in the nation for brand-new infections.
Researchers examined information from 596,618 immunized people aged 16 and over (of whom roughly 170,000 were aged 60+). These people were thoroughly matched with 596,618 unvaccinated people based upon a comprehensive set of market, geographical, and health-related characteristics connected with threat of infection, threat of extreme illness, health status, and health looking for habits. Individuals were designated to each group dynamically based upon their altering vaccination status (roughly 85,000 people moved from the unvaccinated friend into the immunized friend throughout the research study). Multiple level of sensitivity analyses were carried out to make sure that the approximated vaccine efficiency was robust to prospective predispositions.
The results program that in completely immunized people (7 or more days after the 2nd dosage), the threat of symptomatic COVID-19 reduced by 94% compared to the unvaccinated, while the threat of extreme illness reduced by 92%. In the duration instantly preceding the 2nd dosage (days 14-20 after the very first dosage), vaccine efficiency was lower, however still significant — the threat of symptomatic COVID-19 reduced by 57% in immunized people, and the threat of extreme illness by 62%. While there was inadequate information to supply a quote on the decrease in death in those who got 2 dosages, information from 21-27 days after the very first dosage indicate a significant decrease in death too.
As an observational research study carried out in a mass-vaccination setting, this research study was not created to methodically examine viral transmission or asymptomatic infections. With the cautious matching treatments, numerous results evaluated and numerous level of sensitivity analyses carried out, the big sample size in this research study likewise enabled the evaluation of vaccine efficiency in a variety of particular subpopulations. The vaccine efficiency for avoiding symptomatic COVID-19 showed constant throughout age, consisting of grownups aged 70+. The research study likewise examined subpopulations with various varieties of comorbidities and discovered signs that vaccine efficiency for avoiding symptomatic COVID-19 might be a little lower for people with a greater variety of comorbidities, although the distinction was not statistically substantial.
The research study was carried out by Dr. Noa Dagan, Dr. Noam Barda, Dr. Eldad Kepten, Oren Miron, Shai Perchik, Dr. Mark Katz and Prof. Ran Balicer from the Clalit Research Institute, along with Prof. Miguel Hernán and Prof. Marc Lipsitch of the Harvard T.H. Chan School of Public Health, and Prof. Ben Reis of Boston Children’s Hospital and Harvard Medical School.
“The swift nationwide rollout of Israel’s COVID-19 vaccination campaign provided the Clalit Research Institute with a unique opportunity to assess, through its rich digital datasets, the effects of the vaccine in a real-world setting in all population sub-groups,” stated Prof. Ran Balicer, senior author of the research study, Director of the Clalit Research Institute and Chief Innovation Officer for Clalit. “These results show convincingly that this vaccine is highly effective against symptomatic COVID-19, one week after the second dose. These results are similar to those reported in the previously published clinical trial, despite the challenges inherent in a mass-vaccination setting.”
“The results also correlate well with recent population-level trends in Israel, which have seen a sustained decline in hospitalization and severe disease in the mostly-vaccinated older age groups, alongside a delayed decline among younger age groups for whom vaccination began several weeks later. These data, together with the anticipated impact of the ongoing vaccination campaign in Israel, where nearly half the population has already been vaccinated, have had a significant impact on government decisions to ease restrictions imposed during Israel’s recent third lockdown,” describes Prof. Balicer, who likewise works as Chairman of Israel’s National Expert Advisory Team on COVID-19 reaction.
Prof. Miguel Hernán of the Harvard T.H. Chan School of Public Health, stated, “This research is a perfect example of how randomized trials and observational healthcare databases complement each other. The original trial of the Pfizer/BioNTech vaccine provided compelling evidence of its effectiveness to prevent symptomatic infection, but the estimates for severe disease and specific age groups were too imprecise. This analysis of Clalit’s high-quality database emulates the design of the original trial, uses its findings as a benchmark, and expands upon them to confirm the vaccine’s effectiveness on severe disease and in different age groups. This combination of evidence from randomized trials and observational studies is a model for efficient medical research, something which is especially important in COVID times.”
Prof. Marc Lipsitch, Director of the Center for Communicable Disease Dynamics and Professor at the Harvard T.H. Chan School of Public Health, stated, “In all studies of vaccine effectiveness, a major challenge is to ensure that those we are comparing to identify the vaccine’s effect are similar in the other characteristics that may predict whether they get infected or ill. This is especially hard in the context of a rapidly growing, age-targeted vaccine campaign. Clalit’s extraordinary database made it possible to design a study that addressed these challenges in a way that provides tremendous confidence in the inferences that come out of the study.”
Prof. Ben Reis, Director of the Predictive Medicine Group at Boston Children’s Hospital and Harvard Medical School, stated, “Israel’s impressive vaccination campaign, together with Clalit’s unique integrated data sources, presented a rare opportunity to study the effects of the vaccine in a real-world mass-vaccination setting.” He continued, “The global scientific cavalry charge that enabled the development of vaccines in record time is now continuing with international collaborations focused on evaluating vaccine effectiveness. The virus doesn’t recognize borders, neither should the scientists hoping to fight it. This is how science should be done.”
Reference: “BNT162b2 mRNA Covid-19 Vaccine in a Nationwide Mass Vaccination Setting” by Noa Dagan, M.D., Noam Barda, M.D., Eldad Kepten, Ph.D., Oren Miron, M.A., Shay Perchik, M.A., Mark A. Katz, M.D., Miguel A. Hernán, M.D., Marc Lipsitch, D.Phil., Ben Reis, Ph.D. and Ran D. Balicer, M.D., 24 February 2021, The New England Journal of Medicine.