A potential cohort research protocol_ monitoring and surveillance of hostile occasions following heterologous booster doses of Oxford AstraZeneca COVID-19 vaccine in earlier recipients of two doses of Si


Common goal

Measuring security of the booster doses of AstraZeneca vaccine in folks vaccinated with two doses of Sinopharm or Sputnik V vaccines in Iran.

Particular goals

1) To Estimate the incidence of several types of severe hostile occasions (SAEs) inside 13 weeks in all enrolled vaccinated people after both the primary or second booster vaccination with AstraZeneca. 2) To estimate the incidence of several types of hostile occasions of particular Pursuits (AESIs) inside 13 weeks. 3) To estimate the incidence of COVID-19 after both the primary or second booster dose of A in all enrolled folks.


The current research is an energetic COVID-19 vaccine security surveillance by means of an observational potential cohort research that can be carried out in vaccination facilities in Iran. The current protocol has been developed based mostly on the COVID-19 vaccine security steerage handbook launched by the WHO in 2020 [11].

Research settings

The research can be carried out in all main cities of Iran. Research websites are vaccination facilities the place the AstraZeneca is run to the cohort inhabitants. Though vaccination towards COVID-19 can be completed in all well being care facilities plus different non permanent areas, AstraZeneca has been supplied in some predefined facilities. In every web site studied besides Tehran, there can be a vaccination middle to gather information on folks get vaccinated by Astrazeneca. In Tehran, three vaccination facilities have been decided to gather such information. Completely, we are going to acquire information in all main cities. Research websites and vaccination facilities can be chosen by the Ministry of Well being and Medical Training (MOHME). With the intention to obtain the earlier historical past of vaccination, we get entry to Built-in Public Well being System (IPHS). Desk 1 reveals traits of the cohort websites within the current research.

Desk 1 The principle variables of the research gathered in enrolment and comply with up questionnaires Full measurement desk

Research interval

The time level for enrolment can be both the primary or second booster vaccination with AstraZeneca in one of many research websites, after major vaccination with Sinopharm or Sputnik V.

Every particular person can be followed-up for 13 weeks after both the primary or second booster vaccination with AstraZeneca vaccine. 13 weeks follow-up interval was chosen as a result of this covers the commonest danger home windows for AESIs (42 days).


The research inhabitants consists of all enrolled people who’ve acquired two doses of Sinopharm vaccine and both the primary or second booster dose of AstraZeneca in keeping with the nationwide tips for immunization towards COVID-19 in Iran in 2023. As well as, those that have been vaccinated with two doses of Sputnik V and acquired the primary or second dose of AstraZeneca recruited. Research participation is strictly voluntary, and signed knowledgeable consent is obtained from all contributors. The method of together with contributors within the current cohort research is proven in Fig. 1.

Fig. 1 The move chart of together with contributors within the current cohort research Full measurement picture

Inclusion standards

Written knowledgeable consent.

Willingness to proceed to take part within the research till 3 months.

Enrolled people who’ve acquired the first vaccination with two doses of Sinopharm or Sputnik V and both the primary or second booster vaccination with AstraZeneca vaccine.

Exclusion standards

People unable to adjust to research procedures (e.g. Folks with mental disabilities).

People who’ve acquired booster vaccination by AstraZeneca neither as the primary nor because the second booster vaccination.

Those that are lower than 18 years outdated.

Pattern measurement estimation

Concerning the WHO’s protocol, the pattern measurement required to rule out an occasion with a frequency of 1 per 3,333 with a 95% confidence interval is 10,000 per vaccine [11]. Due to this fact, we’re planning to incorporate 20,000 and 10,000 eligible folks with earlier vaccination with Sinopharm and Sputnik V respectively. Concerning the upper proportion of immunization protection for the Sinopharm vaccine in comparison with Sputnik V in Iran, we are going to embody extra vaccinated folks with the Sinopharm vaccine within the current research. Members can be thought of to have accomplished the research once they have accomplished the final questionnaire 13 weeks after the booster dose. The tip of the research is outlined as the purpose at which the final topic enrolled has reached the three months follow-up interval. On this research, comfort sampling can be used to incorporate eligible contributors till reaching the required pattern measurement.

Topic recruitment and comply with up

Individuals who strategy to one of many vaccination facilities for booster vaccination, if they’re eligible to be included, they are going to be consulted and get knowledgeable concerning the challenge. In the event that they settle for to take part, they are going to be requested to signal the consent type. On a day of vaccination, all of the required data can be recorded on a web-based questionnaire. For weekly comply with up, the research employees will name the participant by telephone to gather information if the participant don’t use the net utility for self-reporting of hostile occasion. After two unsuccessful makes an attempt to contact the participant by phone, their subsequent of kin can be contacted. After two unsuccessful makes an attempt to contact their subsequent of kin, the participant can be thought of misplaced to follow-up if they don’t full the questionnaire by self-report. Actually, the contributors are in a position to present self-reported solutions to all web-based questions utilizing the cell phone or a pc. The makes an attempt to contact can be documented. We’ll report the underlying purpose for withdrawal. Withdrawn contributors and people misplaced to follow-up won’t get replaced after the enrolment interval has ended.

To establish SAEs and AESIs, every particular person can be followed-up for 13 weeks after the booster dose of the AstraZeneca vaccine. The diagnoses reported by the contributors throughout follow-up can be examined by a scientific committee together with specialists within the subject of infectious ailments, epidemiology, virology/immunology, inner ailments and others if wanted. Such committees have been established by every college and they’re involving in confirming the prognosis for all SAEs and AESIs. As well as, there’s a nationwide committee to research hostile occasions associated to vaccines, and subsequently for all SAEs and AESIs, the sufferers’ recordsdata can be mentioned in such committee. Such investigation helps contributors to be handled inside an ordinary protocol underneath the supervision of a scientific group.

As per WHO advice, all pregnant ladies inadvertently uncovered to COVID-19 vaccine will comply with up month-to-month till supply, and the being pregnant final result can be documented whether it is attainable. Though the out there proof doesn’t totally help using AstraZeneca amongst pregnant ladies, we don’t exclude such contributors in the event that they oblige to get a booster vaccination with AstraZeneca. The next maternal AESIs can be investigated amongst pregnant ladies: Maternal demise and hospitalization, maternal thrombotic occasions, hypertensive issues of being pregnant, miscarriage/spontaneous abortion, stillbirth, preterm start, neonatal demise, microcephaly, main congenital anomalies, toddler demise.

Research variables

Our unbiased variables embody:

Age: Calculated as distinction between enrolment date and the date of start for individuals who will take part within the research.

Gender (Nominal variable): Male/Feminine.

Training (Ordinal variable): Complete variety of years of training.

Self-reported underlying well being situation (Binary variable: sure/no): An underlying well being situation is a persistent or long-term sickness, which in flip weakens the immune system.

Self-reported weight (kg): The physique weight for every respondent in our information set measured in kilogram.

Self-reported top (cm): The physique weight for every respondent in our information set measured in centimeter.

Place of residence: The province the place folks dwell.

Actual date of pervious vaccinations.

Different important variables of the current research gathered in enrollment and follow-up questionnaires is proven in Desk 2.

Desk 2 The principle variables of the research gathered in enrolment and comply with up questionnaires Full measurement desk

Publicity of curiosity

The publicity of curiosity is both the primary or second booster vaccination with AstraZeneca after the first vaccination with Sinopharm or Sputnik V. The COVID-19 vaccine model, dose, vaccination date and batch quantity can be recorded.

Research outcomes

Critical hostile occasions (SAEs): hospitalization, demise

Critical hostile occasions (SAEs) is outlined as any over-night hospitalization or demise. SAEs that result in in-patient hospitalizations can be reported by the participant or their subsequent of kin, and SAEs that ends in demise can be reported by their subsequent of kin [12].

Adversarial occasions of particular curiosity (AESI) leading to hospitalization

Based on the WHO’s protocol template, the record of AESIs (Desk 2) includes occasions which have a confirmed relationship with immunization or a theoretical concern in keeping with immunopathogenesis of COVID-19 illness [12].

Sever COVID-19

Extreme COVID-19 illness is outlined as COVID-19 illness leading to blood oxygen saturation < 90%, indicators of pneumonia and indicators of extreme respiratory misery. Prevalence of COVID-19 illness can be solicited all through follow-up to gather data on laboratory-confirmed prognosis or not [12]. Within the current research, the incidence of COVID-19 relies on scientific manifestations recognized by well being professionals or/and the polymerase chain response (PCR) take a look at. Knowledge administration We'll develop an information administration plan (DMP) earlier than information assortment begins and can describe all capabilities, processes, and specs for information assortment and cleansing. Research employees will enter information in an digital questionnaire at a number of time factors. The research employees will enter the contributors’ data, contact particulars and information on the exposureat the time of vaccination and all different covariates. Knowledge safety Within the current research, we saved the key-coded information in a secured database situated in Iran. Knowledge can be dealt with consistent with all relevant information safety and privateness legal guidelines. No unauthorized individuals can have entry to the information. Knowledge can be archived for 10 years, as per nationwide laws, and can then be destroyed. Knowledge can be saved in a safe server atmosphere and can be supplied to researchers with an accredited proposal by the challenge information supervisor. Analyses can be completed on de-identified information by licensed researchers. Supply paperwork The information sources for the publicity of curiosity can be contributors and registered information. We must always word that by including the Nationwide code for every participant, all required data relating to the earlier historical past of vaccination can be added to the net based mostly questionnaire. The information supply for covariates would be the contributors as properly. The information sources for the research outcomes would be the questionnaires accomplished by the contributors (or their subsequent of kin) in addition to documentation from hospital and the colleges committees in addition to the nationwide committee. Knowledge retention and archiving Paperwork that individually and collectively allow analysis of the research conduct and the standard of the information produced can be retained for 10 years in accordance with good pharmacoepidemiological apply tips. It will embody the analytical information, evaluation applications, and all output generated. High quality assurance, monitoring, and reporting For every province, a Co-PI can be chosen who has direct communication with the PI and the central workforce. Distant and on-site monitoring of the research conduct can be carried out all through the research interval to evaluate the accuracy and completeness of the information. The research web site could also be topic to a top quality assurance go to. In that case, the location can be contacted upfront to prepare a monitoring go to. The investigator and web site employees will guarantee direct entry to all research paperwork for high quality assurance screens. The central workforce, included the authors of the current research, will management the standard of knowledge as soon as per week to establish errors, outliers and lacking information. Moreover, we are going to extract 1% of knowledge randomly and call contributors to verify they're adequately knowledgeable concerning the current research and know easy methods to full net based mostly follow-up questionnaires. The examination of medical data can be carried out within the KUMS and the nationwide committees. The committees will examine medical data to approve or reject the affiliation of the booster dose with a well being final result. Interim analyses and reporting For the research outcomes, interim analyses can be carried out month-to-month however the formal report can be launched inside 1.5, 3, and 6 months. Such stories can be disseminated to all formal organizations and Iranian medical universities (together with the Iranian Ministry of Well being and Medical Training and WHO by request). As well as, the report can be revealed in related medical journals. Ultimate analyses and reporting Ultimate analyses can be carried out and a full research report can be written inside 4 weeks after database lock. Research outcomes can be shared with the nationwide regulatory authorities for regulatory evaluate, and with the nationwide immunization program to tell public well being coverage selections. Research administration This research can be carried out by the principal investigator, Co-PIs. As well as, scientific advisors contribute to the event of supplies, recruitment, coaching and administration of web sites, the digital information seize, and information administration and analyses. The Investigator and all research employees will conduct the current research consistent with the ethics protocols of the Iran Nationwide Committee for Ethics in Biomedical Analysis. All human assets concerned within the conduct of this research can be certified by training, coaching, and expertise to perform their duties. For the aim of this research, in addition to in particular person communication with the PI and the central workforce, the co-PI and all different recruitment employees will participate in two separate coaching periods held by the central workforce and a workforce from Iranian CDC. Statistical evaluation Within the current research, the information on SAEs and AESIs can be included for the entire cohort inhabitants. Individuals who don't report any occasion(s) can be thought of as contributors with out occasion(s). As AESIs can happen even after 42 days following the primary booster dose, the sensitivity evaluation can be completed excluding these AESIs occurring throughout the first 12 days after the second booster dose. We'll calculate the frequency and proportion of contributors reporting AESIs and SAEs by time since vaccination. For the proportions, 95% confidence intervals can be calculated utilizing an actual technique. Noticed-to-expected analyses can be carried out for SAEs and AESIs with an unknown danger window (most definitely scenario). The noticed incidences for AESIs will becompared with background charges from essentially the most acceptable sources. The anticipated price can be age-stratified, and the standardized incidence ratio (SIR) can be calculated. Incidence price of extreme COVID-19 illness (any COVID-19 illness recognized by a healthcare skilled, laboratory-confirmed COVID-19, hospitalization for COVID-19, COVID-19 requiring intensive care unit (ICU) admission, COVID-19 illness leading to demise) can be calculated after both the primary or the second booster dose of the AstraZeneca and throughout the interval of follow-up. The current research can be carried out consistent with the worldwide moral tips for epidemiology research revealed by the Council for Worldwide Organizations of Medical Sciences (CIOMS), the Declaration of Helsinki and its amendments, good epidemiological apply (GEP) tips and the Iran Nationwide Committee for Ethics in Biomedical Analysis. Knowledge safety and privateness laws can be strictly noticed in capturing, forwarding, processing, and storing people’ information. The research protocol and knowledgeable consent varieties can be reviewed and accredited by the Iran Nationwide Committee for Ethics in Biomedical Analysis.