COVID-19 Vaccines a Literature Analysis of the Three First Approved COVID-19 Vaccines in the EU

COVID-19 Vaccines A literature analysis of the three first approved COVID-19 Vaccines in the EU

Morgan Persson

Bachelor thesis, 15 hp Pharmacist program, 300 hp Report approved: Spring 2021 Supervisor: Martin Bäckström. Examinor: Maria Sjölander

Abstract The SARS-CoV-2 virus, more famously known as Coronavirus disease 2019 (“Covid-19”), has claimed over 3.4 million lives worldwide. The virus, belonging to the RNA coronavirus family, emerged from China during the end of 2019 and was declared a global pandemic by the World Health Organization (WHO) in March 2020. The SARS-CoV-2 genome sequence was published and available on January 11th, 2020. Thereafter multiple pharmaceutical companies began researching on a vaccine. The objective of this literature study was to evaluate the efficacy and safety profiles of the three first approved SARS-CoV-2 vaccines in the EU.

This literature study was primarily built on original articles on the three first approved SARS-CoV-2 vaccines in the EU. Two main methods were used to find relevant articles. The primary method was by using the PubMed database and sorting out relevant articles as seen in Table 1 and 4. The focus was randomized control trials for efficacy and safety and/or articles researching efficacy and/or safety. PubMed was used for its robust and large database of articles. The secondary method of finding articles was by searching in The New England Journal of Medicine (NEJM) found in table 2 or in The Lancet, found in table 3. These journals were used primarily for the reason being that papers on the vaccines were originally published in these journals and a lot of other articles regarding the vaccine’s efficacy were published there as well. Articles from NEJM and The Lancet were sorted for relevancy in a similar manner as searches done in PubMed.

All vaccines showcased good protection against severe Covid-19. Zero participants in the trial arm of any of the vaccines died from severe Covid-19. Likewise, all vaccines in their respective trials showcased overall high safety with reactogenicity being mild in all trials. Most common local reactions across all vaccines were post-injection pain, tenderness, and redness. All 0f whom lasted a few days. Likewise, systemic reactions were overall mild to moderate in nature with the most common reactions being fatigue, myalgia (or “muscle pain”), headache(s) and arthralgia (or “joint pain”), these too lasted a few days. In general, the odds of receiving any reaction were high; but the reactions themselves were of modest nature, indicating the vaccines were well-tolerable compared to placebo and/or active control.

Despite its limitations and disadvantages, this paper can showcase that the three first Covid-19 vaccines approved in the EU (BNT162b2; mRNA-1273 and AZD1222) present overall high efficacy and safety for their approved ages. Future research is needed to assess efficacy for Covid-19 variants of concern and efficacy and safety for adolescents

Keywords: COVID-19, COVID-19 Vaccines, SARS-CoV-2, Corona.

Abbreviations and definitions

ACE2 = Angiotensin-Converting Enzyme 2 APCs = Antigen-Presenting Cells ARR = Absolute Risk Reduction CI = Confidence Interval Covid-19 = Coronavirus Disease 2019 dsDNA = double stranded Deoxyribonucleic Acid EMA = European Medicines Agency FDA = Food and Drug Administration HIV = Human Immunodeficiency Viruses IL-6 = Interleukin-6 IL-8 = Interleukin-8 MERS-CoV = Middle East Respiratory Syndrome Coronavirus MHC1 = Major Histocompatibility Complex 1 MHC2 = Major Histocompatibility Complex 2 MHRA = Medicines and Healthcare products Regulatory Agency NIAID = National Institute of Allergy and Infectious Diseases NIH = National Institutes of Health NNT = Number Needed to Treat NNV = Number Needed to Vaccinate PAMPs = Pathogen-Associated Molecular Patterns ORF = Open Reading Frames RBD = Receptor Binding Domain RRR = Relative Risk Reduction SARS-CoV = Severe Acute Respiratory Syndrome Coronavirus SARS-CoV-2 = Severe Acute Respiratory Syndrome Coronavirus 2 ssRNA = single stranded Ribonucleic Acid TMPRSS2 = Transmembrane protease, serine 2 URT = Upper Respiratory Tract

Table of Contents Abstract……………………………………………………………………………………………………………………I Abbreviations………………………………………………………………………………………………………….II 1. Introduction………………………………………………………………………………………………………….1 1.1. The immune system…………………………………………………………………………………………1 1.2. SARS-CoV-2…………………………………………………………………………………………………..1 1.2.1. Origins…………………………………………………………………………………………………….1 1.2.2. Taxonomy……………………………………………………………………………………………….1 1.2.3. Transmission………………………………………………………………………………..…………1 1.2.4. Pathology………………………………………………………………………..………………………1 1.2.5. Risk Factors…………………………………………………………………………………………….2 1.2.6. Genome…………………………………………………………………………………………………..2 1.3. Vaccines………………..………………………………………………………………………………………3 1.3.1. RNA Vaccines: Mechanism of action overview…………………………………………….3 1.3.2. RNA Vaccines: Historical overview……………………………………………………………4 1.3.3. BioNTech-Pfizer………………………………………………………………………………………4 1.3.4. Moderna…………………………………………………………………………………..…………….4 1.3.5. Viral Vector Vaccines: Mechanism of action overview………………………………….5 1.3.6. Viral Vector Vaccines: Historical overview………………………………………………….5 1.3.7. Oxford-AstraZeneca………………..………………………………………………………….……5 1.4. Objective……………………………………………………………………………………………………….6 2. Method……………………………………………………………………………………………………………..…7 3. Results……………………………………………………………………………………………………………….10 3.1. Pfizer: BNT162b2 Phase 2 / 3 trial methodology……………………………………………...10 3.1.1. BNT162b2 Phase 2 / 3 trial participant information…………………………………..10 3.1.2. BNT162b2 Safety……………………………………………………………………………..…….10 3.1.3. BNT162b2 Local reactogenicity…………………………………………………..…………..10 3.1.4. BNT162b2 Systemic reactogenicity………………………………………………….……….11 3.1.5. BNT162b2 Efficacy……………………..…………………………………………………………..11 3.1.6. Articles showcasing BNT162b2 against variants of concern…………………..……12 3.1.7. Adverse events from BNT162b2 seen in practice……………………..…………………12 3.2. Moderna: mRNA-1273 Phase 3 methodology…………………………………………………..12 3.2.1. mRNA-1273 Phase 3 participant information……………………………………………13

3.2.2. mRNA-1273 Safety…………………………………………………………………………………13 3.2.3. mRNA-1273 Local reactogenicity…………………………………………………….………13 3.2.4. mRNA-1273 Systemic reactogenicity…………………………………………….………….13 3.2.5. mRNA-1273 Efficacy………………………………………………………………………………14 3.2.6. Articles showcasing mRNA-1273 against variants of concern…………………..…14 3.2.7. Adverse events from mRNA-1273 seen in practice………………..……………………15 3.3. AstraZeneca: AZD1222 Trial methodology………………………………………………………15 3.3.1 AZD1222 Trials Participant information……………………………………………………16 3.3.2. AZD1222 Safety………………..……………………………………………………………..…….16 3.3.3 AZD1222 Local reactogenicity………………………………………………………………….17 3.3.4. AZD1222 Systemic reactogenicity…………………………………………………………….17 3.3.5. AZD1222 Efficacy…………………………………………………………………………………..18 3.3.6 AZD1222 against variants of concern………………………………………………………..19 3.3.7 Adverse events from AZD1222 seen in practice: Case series………………………..19 3.3.8 Adverse events from AZD1222 seen in practice: Cohort……………………………..19 4. Discussion………………………………………………………………………………………………………..…21 4.1. Result discussion…………………..………………………………………………………………………21 4.1.1. Prevention of Covid-19/severe Covid-19 vaccine efficacy………………..…………..21 4.1.2. Vaccine side effects……………………………..…………………………………………………22 4.1.3. Vaccine efficacy against SARS-CoV-2 variants of concern……………..…………..23 4.1.4. Future research……………………………………………………………………………………..24 4.1.5. Method discussion…………………………………………………………………………………24 4.2. Conclusion…………………………………………………………………………..………………………24 5. Acknowledgements……………………………………………………………………………………………..25 6. References…………………………………………………………………………………………………….……26 Appendix………………………………………………………………………………………………………….…….31

1. Introduction As of writing this paper the severe acute respiratory syndrome coronavirus 2, also known as SARS-CoV-2 virus and more famously as Coronavirus disease 2019 (“Covid-19”), has claimed over 3.4 million lives worldwide (1). The virus, belonging to the ssRNA (single stranded ribonucleic acid) coronavirus family, emerged from China during the end of 2019 (2) and was declared a global pandemic by the World Health Organization (WHO) in March 2020 (2,3).

The coronavirus family, with their characteristic surface protein resembling a crown (Latin: corona for crown), were discovered during the 1960s in humans (4) and as of writing this paper there are seven known viruses within the coronavirus family that infect humans (4,5). Notable examples besides SARS-CoV-2 are MERS-CoV (Middle East Respiratory Syndrome Coronavirus) and SARS-CoV respectively (4,5).

1.1. The immune system When a pathogen enters the human body, it encounters the immune system. Our immune system is compromised of two primary components; the innate and adaptive immune system. Our innate immune system is basic in its function and is our first line of defense, primarily consisting of phagocytes (e.g., macrophages, neutrophils, and so forth). Its most basic function is to protect the human body regardless of invader. Whereas the adaptive immune system (composing of T-lymphocytes such as T-helper cells and Cytotoxic T- Cells or B-lymphocytes such as Clonal- and Memory B-cells) main function is to eliminate pathogens and remember them specifically and methodically. The latter of which is of great importance to vaccines given that they train the adaptive immune system to remember pathogens if the body encounters them in the future (6).

1.2. SARS-CoV-2 1.2.1. Origins SARS-CoV-2 emerged from China during the end of 2019 presumably from the Wuhan region where, at the moment, most probable original transmission is between bats to humans (4). Little evidence suggests that the virus was created in a lab. On the contrary, the virus has multiple components that suggests it is of natural origin, including close relation to natural viruses such as SARS-CoV and 96% shared genome with coronavirus RaTG13. This accompanied with the fact that the receptor binding domain (RBD) is not ideal (i.e., inefficient) makes a strong point of the virus having a natural origin (7).

1.2.2. Taxonomy The virus, being part of the enveloped positive ssRNA coronavirus family (8,9) are characterized by their surface proteins giving them their name (4,8,9). The SARS-CoV-2 virion consists primarily of an outer crown of structural spike proteins, secondary envelope proteins, membrane and a nucleocapsid shell. All of which encapsulate and protect the virus RNA (8,9).

1.2.3. Transmission Transmission and infection of SARS-CoV-2 is an area of research constantly under renewal. Current understanding of transmission and pathology is that the virus is transmitted primarily through respiratory droplets between individuals when, for example, singing, talking, or breathing (10,11,12), though fecal transmission has been proposed as well (10).

1.2.4. Pathology Once SARS-CoV-2 enters the body it is thought to infect primarily through the airways alveolar epithelial cells as it binds to ACE2 receptors through the S-spike of the virus and

RBD of the cell (7,10,13). The pathology is seen as very similar to that of SARS-CoV that emerged in the early 2000s though key differences exist (7,10).

Followed by the binding of SARS-CoV-2 to the ACE2 receptor the spike protein undergoes confirmational change(s) through the human transmembrane protease serine enzyme (TMPRSS2) where it cleaves and activates the protein. Whereafter the membranes of the virion and host cell fuse. This ensures the viral RNA is let into the cell to begin viral multiplication through exploitation of human cells protein synthesis apparatus. This apparatus includes the endoplasmic reticulum, ribosomes, and Golgi apparatus (7,10,13).

Once infected the incubation period is usually 4-6 days, but upwards of two weeks (7,10,13).

Symptoms of SARS-CoV-2 infection are usually mild and include, but are not limited to; coughing, dyspnea, rhinitis, sore throat, fatigue, dizziness, headache, myalgia, nausea, vomiting, chills and/or fever (7,10,14).

The older a patient is and/or the more at risk they are (i.e., comorbidities or risk factors (see more below under risk factors) the higher the association is between contracting SARS-CoV-2 and risk of hospitalization, long-term effects and/or death (8,11). Symptoms that may need medical care include, but are not limited to; confusion, trouble breathing, trouble staying awake, arrhythmia and pneumonia (10,15).

High proportions and markers of proinflammatory activity have been seen in severe SARS- CoV-2 infections such as high levels of macrophages, neutrophils, IL-6(interleukin-6) and IL-8 (interleukin-8). This supports the theory that increased immune response is a considerable factor in the severity of Covid-19 according to at least one paper (10).

1.2.5. Risk factors Risk factors associated with severe Covid-19 include, but are not limited to, cancer, kidney disease, diabetes (type 1 and 2), dementia, HIV, immunosuppressed patients, obesity, and smoking (16).

1.2.6. Genome SARS-CoV-2 is a member of the enveloped, positive ssRNA virus family of coronaviruses and its genome lineage is found to be in line with coronaviruses found in bats. The genome is built on 29,903 base pairs, which is considered large compared to other coronaviruses. In at least 50 different sites within the genome there exists open reading frames (ORFs) where translation from RNA to amino acids can begin with the first two thirds of the genome encoding for accessory and non-structural functions. These include replication, proofreading and RNA stabilization. The final third encodes primarily structural proteins, although accessory proteins are encoded there as well (8).

The structural proteins that give SARS-CoV-2 its form; spike (S), membrane (M) and envelope (E) are embedded in the outer membranes. The RNA is protected inside where it is tightly coiled and coated with the fourth structural protein nucleocapsid (N) (7,8). Illustration shown in Figure 1.

Figure 1. SARS-CoV-2 illustration derived from Glasgow University by A. Slater (17).

SARS-CoV-2 shares ~80% of genome identity with SARS-CoV and ~50% with MERS-CoV (6,7). The nucleotide identity between SARS-CoV and SARS-CoV-2 S-spike protein is <75%. A theory behind why SARS-CoV-2 is more transmissible than SARS-CoV is this change in structure making SARS-CoV-2 more effective in upper-respiratory-tract (URT) infections compared to SARS-CoV. Given that ACE2 receptors are more prevalent in oral and nasal tissue and the possible higher affinity for these receptors of SARS-CoV-2 compared to SARS-CoV (7).

The virus has a mutation rate of approximately 8 x 10-4 nucleotide substitutions per year. Given the almost 30 000 base pairs this approximates to around 23,127 substitutions per year, around 2 per month. Lower than influenza or SARS-CoV (8).

Hundreds of SARS-CoV-2 variants of concern are being monitored and focused on during the global pandemic (18). These include most famously lineage B.1.1.7 (“UK variant”), lineage B.1.351 (“South African variant”), and lineage P.1 (“Brazilian variant”) (19).

1.3. Vaccines The SARS-CoV-2 genome sequence (20) was published and available on January 11th, 2020 (20). Thereafter multiple pharmaceutical companies began researching on a vaccine (21). As stated earlier this paper will focus on the three first approved SARS-CoV-2 vaccines in the EU. These being, in order of date, BioNTech-Pfizer, Moderna and Oxford- AstraZeneca.

1.3.1. RNA Vaccines: Mechanism of action overview Ribonucleic acid vaccines, also known as messenger ribonucleic acid (mRNA)-vaccines, are vaccines that use the mRNA molecule to produce an immune response. The mechanism of action acts through an uptake in target cell(s) and production of proteins the RNA encodes for (antigens). The antigens then produce an immune response as if the pathogen to which the antigen belongs was present (22). Key advantages for RNA vaccines include the fact that they are easy and fast to manufacture, an easy way to elicit cytotoxic T-cell (CTL) responses similar to viral infections and can evoke both major histone complex (MHC) I and II presentation (p. 6-8, (23)).

Both Comirnaty (24) (also known as BNT162b2) from BioNTech-Pfizer and mRNA-1273 (from Moderna) are mRNA lipid-nanoparticle vaccine encoding for the SARS-CoV-2 S- spike protein in prefusion confirmation. Meaning the immune response is toward the S- pike protein antigen before membrane fusion of the virion and host cell. The mRNA is 3 enveloped by a lipid-nanoparticle coating that ensures it is protected from degradation and allows the mRNA-molecule to enter the cell through endocytosis (25).

1.3.2. RNA Vaccines: Historical overview RNA vaccines have been researched since 1989 where they observed liposomal nanoparticles could transfer mRNA into eukaryotic cells (p. 5 (23)). During the 1990s RNA vaccines were shown to employ immunological response from T-cells in vivo (26). Research continued through the 1990s and into the 2000s (p. 8-14, (23)). A downside historically to mRNA vaccines has been that they are fragile and easily succumb to metabolic processes and breakdown (p. 14, (23)).

Katalin Karikó, a Hungarian biochemist specialized in RNA technology, along with American physician Drew Weissman, worked together researching on eliciting appropriate immune response from RNA mediated pharmaceuticals. They together published multiple papers culminating in one from 2005 showing RNA produced immune response without setting off vast amounts of cytokines (27). Both Moderna and BioNTech licensed Karikó and Weissman’s work to develop their RNA vaccines. Karikó is since 2013 employed as the senior vice president at BioNTech (28).

The German pharmaceutical Company CureVac was founded in 2000 (29) where founder Ingemar Hoerr wrote in part his PhD on RNA vaccines (30). They are also now developing a SARS-CoV-2 vaccine (31).

On December 2nd, 2020 in the United Kingdom the Medicines and Healthcare products Regulatory Agency (MHRA) approved the BioNTech-Pfizer RNA vaccine (32). Making it the first of its kind in history approved for humans.

1.3.3. BioNTech-Pfizer The BioNTech-Pfizer vaccine sold under Comirnaty (24) and codenamed BNT162b2 (25) is an mRNA vaccine against SARS-CoV-2 developed by German pharmaceutical company BioNTech with help in trials, logistics and manufacturing from American pharmaceutical company Pfizer (33).

BioNTech started vaccine research under “Project Lightspeed” on January 12th, 2020 and entered collaboration with Pfizer to commercialize the vaccine on March 16th, 2020. Four different candidates started phase 1 / 2 trial on April 22nd, 2020 in Germany and April 23rd, 2020 in USA. On July 2nd, 2020 global phase 2 /3 study started on the candidate vaccine BNT162b2, also now known as Comirnaty, in the USA, Argentina, Brazil and Germany (34). The vaccine was subsequently approved on December 21st in the EU by the European Medicine Agency (EMA). The vaccine is, as of yet, only approved for the ages of 16 or 18 (depending on region) and older (24).

1.3.4. Moderna COVID-19 Vaccine Moderna, also known by the codename mRNA-1273, is an mRNA vaccine against SARS-CoV-2 developed by American pharmaceutical company Moderna in collaboration with the American National Institute of Allergy and Infectious Diseases (NIAID) a part of the American National Institutes of Health (NIH) (35,36).

Moderna and NIH research team finalized the sequence for mRNA-1273 on January 13th, 2020, two days after the SARS-CoV-2 genome sequence was published. Thereafter the vaccine candidate proceeded to phase 1 trial on March 26th, 2020 in the USA. Phase 2 trials began on May 29th, 2020 in the USA and phase 3 trials on July 27th, 2020 in the USA (37). mRNA-1273 was subsequently approved by the EMA in the EU on January 6th, 2021 for ages, as of yet, 18 and older (35).

1.3.5. Viral Vector Vaccines: Mechanism of action overview Viral vector vaccines use another (harmless) virus, a vector, to deliver nucleic acid coding for the antigen from the pathogen of choice. They have been shown to elicit both long term exposure immunity, safety, and adequate CTL response. Disadvantages have been primarily from pre-existing immunity from the viral vector and some viral vectors, primarily those using retroviruses and lentiviruses, have shown potential for tumorigenesis (38).

The Oxford-AstraZeneca SARS-CoV-2 vaccine is a viral vector vaccine based on adenovirus (39). Viral vector vaccines using adenoviruses have not been shown to be tumorigenic, though they have had issues historically regarding immunity from the viral vector (38). AZD1222 (40), also known as Vaxzevria in the EU (41) and ChAdOx1-nCoV-19 (40), is a recombinant, replication-deficient adenovirus vector vaccine containing the genome coding for the prefusion conformation of the SARS-CoV-2 S-spike glycoprotein antigen. The carrier virus (adenovirus) genome is constructed by inserting the prefusion confirmation SARS-CoV-2 S-spike gene into the adeno genome itself. Thereafter the virus can reproduce in cell lines and is thereafter purified. Once injected the immune response of the target cells will produce antibodies towards the encoded S-spike protein in prefusion confirmation (42,43).

Adenoviruses double stranded Deoxyribonucleic Acid viruses (dsDNA) and have been shown to be highly immunogenic, presumably by expressing pathogen-associated molecular patterns (PAMPs). PAMPs bind to host cells, including those in the innate immune system, and thereafter, induce an immune response across varying cells including differentiation of immature dendritic cells into professional antigen-presenting cells (APCs). CD4+, CD8+ and B-cell induced response has also been shown in trials (42,43,44).

1.3.6. Viral Vector Vaccines: Historical overview Research on using viral vectors for vaccines has been ongoing since the 1970s (44) with the concept being introduced by Jackson et al., when they introduced genetic material into simian vacuolating virus in 1972 (44). Since then, viral vector vaccines have been involved in recent Ebola outbreaks (43) and the technology has been focused on other diseases such as Zika and HIV (43). Most recently the Oxford-AstraZeneca vaccine against SARS-CoV-2 was approved using viral vector technology (41).

1.3.7. Oxford-AstraZeneca The Oxford-AstraZeneca vaccine is a co-developed adenovirus vector vaccine from University of Oxford in the United Kingdom and British-Swedish pharmaceutical company AstraZeneca (40,41). It is sold under the name Vaxzevria in the EU (41) and is codenamed AZD122 (45) and also known by the name ChAdOx1-nCoV-19 stemming from its recombinant adenovirus vector (ChAdOx1) nature and the pathogen SARS-CoV-2 (45).

The vaccine began development as soon as the genetic information of SARS-CoV-2 was released. An agreement between Oxford and AstraZeneca meant the production and scaling could be easily accomplished. Phase 1 trials began in the UK in April 2020 with phase 2 and 3 trials taking place between April to November of 2020 (46). The vaccine was subsequently approved by the EMA in the EU for ages 18 and over on January 29th, 2021 (41).

1.4. Objective The objective of this literature study is to evaluate the efficacy and safety profiles of the three first approved SARS-CoV-2 vaccines in the EU. Given the ongoing pandemic and debate regarding vaccines this paper holds high relevancy for the time it is written in. This paper will primarily be evaluating the vaccines independently given there does not exist original trials comparing vaccines. When possible and suitable, however, comparisons will be made between the three vaccines. This paper will try and answer the following questions:

- How effective are the vaccines against protection from Covid-19 and/or severe Covid-19? - Which vaccine expresses the highest efficacy? - What are the most common side effects from the vaccines and which vaccine expresses the fewest side effects? - How effective are the vaccines against SARS-CoV-2 variants?

2. Method This literature study was primarily built on original articles on the three first approved SARS-CoV-2 vaccines in the EU. Two main methods were used to find relevant articles. The primary method was by using the PubMed database and sorting out relevant articles as seen in Table 1 and 4. The focus was randomized control trials for efficacy and safety and/or articles researching efficacy and/or safety. PubMed was used for its robust and large database of articles. The secondary method of finding articles was by searching in The New England Journal of Medicine (NEJM) found in table 2 or in The Lancet, found in table 3. These journals were used primarily for the reason being that the original papers on the vaccines were published in these journals and a lot of other articles regarding the vaccine’s efficacy were published there as well since they are highly accredited journals. Articles from NEJM and The Lancet were sorted for relevancy in a similar manner as searches done in PubMed.

Searches were made between 2021-03-23 and the cutoff date 2021-05-14 using appropriate filters as seen in the table overview for each method. If filters were not used, as seen in searches in table 3, then it was due to the filters not revealing all relevant literature for this paper. Given the present and ongoing pandemic and the mass of information emerging, filtering was often done by publication date and sorted by most recent or equivalent. Sorting for clinical trials often rendered zero results. For more information about each search see each table, respectively.

Exclusion criteria for articles not being included in this paper were 1) systemic reviews or 2) meta-analyses. The end-goal was to only use original articles such as the original vaccine trials (of which preferably were phase 3), RCTs, and cohorts. Case studies and correspondence articles were used as supplementary material in safety and efficacy evaluation. These can be found in table 2, 3 and 4.

Table 1. Article searches in PubMed for main studies. PubMed Search terms Filters Results Number of Reference #Search articles numbers chosen

#1 “AstraZeneca” AND Article 5 1 57 “chadox1 nCoV-19” type: OR “azd1222” Clinical trial

Sorted by: Most recent

#2 “Moderna” AND Article 5 1 51 “mRNA-1273” type: Clinical trial

Sorted by: Most recent

#3 “Pfizer” AND Article 2 1 47 “BioNTech” AND type: “bnt162b2” Clinical trial

Sorted by:

Most recent

Table 2. Article searches in The New England Journal of Medicine for additional efficacy evaluation. NEJM Search Filters Results Number of Reference #Search terms articles chosen numbers

#1 “BNT162b2” Filter: 16 2 49, 62 Newest

#2 “mRNA- Filter: 18 2 54, 55 1273” Newest

Table 3. Article searches in The Lancet for additional efficacy evaluation. Lancet Search Filters Results Number of Reference #Search terms articles chosen numbers

#1 “AZD1222” Filter: 35 1 61 None

Table 4. Article searches in PubMed for additional safety and efficacy evaluation. PubMed Search terms Filters Results Number of Reference #Search articles numbers chosen

#1 “ChAdOx1 nCoV-19” OR Article 17 3 50, 63, 66 “azd1222 AND type: “thrombosis” [MeSH] None

Sorted by: Most recent

#2 “azd1222” OR “chadox1 Article 27 2 64, 65 ncov-19” AND type: thrombocytopenia None

Sorted by: Most recent

#3 “mRNA-1273” AND Article 2 1 56 “thrombocytopenia” type: [MeSH] None

Sorted by: Most recent

3. Results Supplementary data for figures and tables referenced under Results can be found in the Supplementary Appendix accompanying this paper.

3.1 . Pfizer: BNT162b2 Phase 2 / 3 trial methodology BioNTech-Pfizer Phase 2 / 3 trials were run in parallel. Two 30 µg doses of BNT162b2 (0.3 ml volume per dose) were administered intramuscularly (IM) 21 days apart and compared to placebo (saline solution) in a randomized, observer blind-blinded trial (meaning everyone besides administrator(s) are blinded) in participants 16 years and older (47). Participants in the trial also included patients with stable chronic medical conditions, including but not limited to HIV, hepatitis C and B. Exclusion criteria included for example pregnancy, medical history of SARS-CoV-2 infection; immunosuppressive therapy and immunocompromising diseases/conditions (p. 177- 182 (48)).

Participants were randomly divided into two groups in a 1:1 ratio to either receive BNT162b2 or placebo and were investigated for 30 minutes after each administration for acute reactions with safety monitoring for 2 years after second administration (47).

Primary study endpoint was of vaccine efficacy against confirmed Covid-19 with onset ≥7 days after second dose administration in participants without prior evidence of SARS-CoV-2 infection. Primary secondary endpoint was efficacy in participants with and those without evidence of prior infection (47).

Confirmed Covid-19 was defined by the FDA as seen in table 1 found in Appendix. Major secondary endpoint included BNT162b2 efficacy against severe Covid-19 as defined by criteria seen in table 2 found in Appendix.

3.1.1. BNT162b2 phase 2 / 3 trial participant information Between July 27th, 2020 and November 14th, 2020 43,548 participants age >16 underwent randomization into two groups at 152 sites around the world (130 sites in the USA; 1 in Argentina; 2 in Brazil; 6 in Germany, 9 in Turkey; and 4 in South Africa) and a total of 43,448 received two doses of either BNT162b2 or placebo (47).

At the cut-off date of October 9th, the dataset of participants was reduced to 37,706 due to withdrawal, lost to follow up, or other reasons. These 37,706 participants were used for the 2-month safety data. Participant demographic was 51.1% male and 48.9% female and primarily white (82.9%), thereafter Hispanic (28%), black or African American (9.3%) and Asian (4.3%) with other ethnicities ranging from 2.2-0.5%. Participants could choose more than one ethnicity. 28,914 (76.7%) of participants were in the USA. The median age of the study participants was 52 years with a range of 16- 91 years. In both the BNT162b2 trial group and the placebo group 42% of participants were >55; 58% of participants were 16-55. (47).

3.1.2. BNT162b2 Safety Reactionary subset, i.e., participants used to track local and systemic events, was 8,183 participants and utilized a self-reporting system using an electronic diary and on-call physician for guidance whenever needed (47).

3.1.3. BNT162b2 Local reactogenicity Local reactions (i.e., at and around injection site) were graded after a 4-part grading scale in reaction severity from 1) mild; 2) moderate; 3) severe and 4) potentially life threatening.

The most common local reaction was pain at the injection site in both groups. Group 1 (age: 16-55) in the BNT162b2 arm reported 83% post-injection pain after the first injection; after the second injection the same BNT162b2 group reported 78% post 10 injection pain. Group 2 (age: >55) in the BNT162b2 arm reported 71% post injection pain after the first injection; after the second injection the same BNT162b2 group 2 reported 66% post-injection pain (47).

Other, to a lesser degree (≤7%), reported local reactions were redness and swelling. No one in either groups reported grade 4 local reactions and the vast majority (>95%) of reported local reactions were mild to moderate with an even split between the two (47).

Placebo groups, regardless of age, reported local reactions to a much lesser degree than BNT162b2 group. The most common local reaction was reported after the first dose from the placebo group in age group 16-55, of which 14% reported post-injection pain (47).

A full list and breakdown of local reactions comparing BNT162b2 groups and placebo groups can be seen in Figures 1-4 found in Appendix.

3.1.4. BNT162b2 Systemic reactogenicity Systemic reactions utilized a similar 4-part grading in reaction severity scale from 1) mild; 2) moderate; 3) severe and 4) potentially life threatening.

The most common reported systemic reaction came after the second injection from group 1: ages 16-55 and was fatigue, of which 59% reported it compared to 51% reporting fatigue after the second dose in group 2: ages >55. The second most common systemic reaction was headaches. This too after the second dose, of which 52% reported it in group 1: ages 16-55 compared to 39% in group 2: ages >55 (47).

Severe systemic reactions overall were rare with reporting of <0.9% after first dose and <2% after the second dose. Fever was reported in a higher frequency in group1: age 16- 55 compared to the group 2: age >55 group (16% and 11% respectively). ≤1% of placebo participants reported fever (47). More statistics on systemic side effects can be seen in figures 5-8 found in Appendix.

Adverse events overall were reported to a higher degree in the BNT162b2 arm compared to placebo (27% compared to 12%). 64 participants (0.3%) in the BNT162b2 arm and 6 participants (<0.1%) in the placebo arm reported lymphadenopathy and 4 other related adverse events were reported in the same arm (right leg paresthesia; paroxysmal ventricular arrythmia, right axillary lymphadenopathy and shoulder injury stemming from vaccine administration) (47).

Two participants in the BNT162b2 arm died (one died from arteriosclerosis and another one died from cardiac arrest). Four died in the placebo arm from various causes. No deaths in either groups were associated with either BNT162b2 or placebo (47).

3.1.5. BNT162b2 Efficacy Out of 36,523 participants (N=18,198 in BNT162b2 group; N=18,325 in placebo group) with no prior nor existing evidence of SARS-CoV-2 infection there were 8 cases of Covid-19 with onset ≥7 days after the second dose in the vaccine group compared to 162 cases in the placebo group. This equals out to a relative reduction rate (RRR) or vaccine efficacy of 95% (confidence interval (CI) 90.3 to 97.6%). Accounting for total population of those with and without prior SARS-CoV-2 infection (N=40,137 total. N=19,965 in BNT162b2 group; N=20,172 in placebo group) there were 9 cases of reported Covid-19 infection with onset ≥7 days after the second dose compared to 169 in the placebo group, this corresponding to a vaccine efficacy (RRR) of 94.6% (95% CI; 89.9 to 97.3%) for prevention of symptomatic Covid-19 as compared to placebo (47).

For participants with hypertension the efficacy (RRR) was 94.6% (95% CI; 68.7 to 99.9%) with 2 cases of Covid-19 in the BNT162b2 group compared to 44 cases in the placebo group. The trial lacked sufficient data on BNT162b2 efficacy on asymptomatic Covid-19 (47).

3.1.6. Articles showcasing BNT162b2 against variants of concern A correspondence paper from Yang Liu et al., published on April 15th, 2021 in NEJM engineered recombinant viruses representing the different SARS-CoV-2 variants of concern lineages (B.1.351, B.1.1.7, P.1 and two more) with the engineered variants mutations being equivalent to that of their real-world counterparts according to the authors. Yang Liu et al., performed neutralization testing on 20 serum panels from 15 participants who, between 2 and 4 weeks prior, had received a second dose of BNT162b2. The authors note that BNT162b2 was effective against the B.1.1.7 and P.1 lineage, but less so on the B1.351 variant. The test was done in vitro (49).

3.1.7. Adverse events from BNT162b2 seen in practice An article from David M. Smadja, et al., utilized VigiBase, a databank developed and maintained by Uppsala Monitoring Centre (UMC) in Sweden, to look at reported side effects on BNT162b2. Between December 13th, 2o20 and March 16th, 2021, 361 734 976 people received Covid-19 vaccines. 2161 thrombotic events were reported in Vigibase databank and 1197 were shared for BNT162b2. The authors make no claims of cause and effect or correlation between the events and the vaccine (50).

3.2 Moderna: mRNA-1273: Phase 3 trial methodology In the Moderna phase 3 trial the mRNA-1273 vaccine was administered by injection in the deltoid muscle in two doses, each containing 100 µg mRNA-1273 (0.5 ml volume per dose) spaced 28 days apart and compared to placebo (saline solution) in an observer-blinded, randomized, placebo-controlled trial in participants 18 years and older. Eligibility inclusion criteria were persons >18 years of age without known history of SARS-CoV-2 infection and with locations and/or circumstances that put them at an elevated risk of contracting SARS-CoV-2, high risk of severe Covid-19 and/or both (51).

Exclusion criteria included pregnancy, breastfeeding, prior SARS-CoV-2 infection, immunosuppressive or immunodeficient state (i.e., asplenia or severe HIV-infection), amongst others (p. 126-128 (52)).

Participants were randomly divided into two groups in a 1:1 ratio to receive either mRNA-1273 or placebo. Assignment was stratified based on risk of Covid-19 complications risk criteria (according to the CDC, i.e., chronic lung disease, cardiac disease, severe obesity and so forth) and age. The three subgroups between the mRNA- 1273 arm and placebo arm were 1) >65 years of age; 2) <65 with a heightened risk for severe Covid-19 and; 3) <65 without heightened risk for severe Covid-19. Vaccine dose preparation and administration were performed by pharmacists and administrators were aware of treatment assignment but did not play any other role in the trial (51).

Primary study endpoint of the trial was vaccine efficacy in prevention of first occurrence of symptomatic Covid-19 infection with onset ≥14 days after the second injection of mRNA-1273 (51). Confirmed Covid-19 was defined by criteria seen in table 3 found in Appendix.

Secondary endpoint of the trial included efficacy against Covid-19 after single dose of mRNA-1273 and the efficacy of mRNA-1273 to prevent severe Covid-19 (51). The definition of severe Covid-19 for this trial can be seen in table 4 found in Appendix.

3.2.1. mRNA-1273 Phase 3 participant information Between July 27th, 2020 and October 13th, 2020, a total of 30,420 participants age >18 underwent randomization into the three groups across 99 places in USA to either receive mRNA-1273 or placebo (51).

At the cut-off date of November 25th, 2020, the dataset of participants was reduced to 28,207. All of these received either mRNA-1273 or placebo. Common reasons for not receiving the second dose according to Moderna included withdrawal, missed timing for second dose and withdrawal of consent, amongst other reasons. Participant demographic was 52.7% male and 47.3% female and primarily white (79.2%), thereafter Hispanic or Latino (20.5%), black or African American (10.2%), Asian (4.6%) and the remaining ethnicities ranging from 2.1-0.9%. Participants could be included into one or more categories (51).

The median age of the study participants was 51.4 with a range of 18-95. The total age demographics in the three previously mentioned subgroups were; 25% were age >65; 17% were age 18-65 with heightened risk for Covid-19; and 58% were ages 18-65 not at heightened risk for Covid-19 (51).

3.2.2. mRNA-1273 Safety Reactogenicity was tracked across all trial arms including placebo. Reactogenicity reporting was done by grouping participants in either placebo or mRNA-1273 group and two subgroups; >18<65 and >65, participants were tracked for seven days after injection to track reactogenicity with a two-year follow-up (51).

3.2.3. mRNA-1273 Local reactogenicity Local reactions (i.e., at and around injection site) were graded after a 5-part grading scale in reaction severity from 0) no reaction; 1) reaction that does not interfere with everyday activity; 2) reaction interferes somewhat with daily activity; 3) reaction inhibits daily activity or 4) requires going to the emergency room and/or hospitalization (p. 157-158 (52)).

The mean duration of local reactions lasted 2.6 and 3.2 days respectively and were rated as grade 1 (52% across all groups after first injection; 53.8% after second injection) with zero grade 4 reactions. The most common local reaction overall was post-injection pain which was after the first dose 83.7% in mRNA-1273 group versus 17.5% in the placebo group. After the second dose the same groups reported 88.2% post-injection pain versus 17% respectively (p. 24-26 (53)).

Other lesser reported local reactions included swelling (reported 6.1% overall), erythema (2.8% overall), and axillary swelling/tenderness (10.2% overall) (p. 24 (53)).

Local reactions after both injections were reported to a higher extent by those age >18<65 than those age >65 and higher overall after the second dose. After the first dose 87.4% of participants aged >18<65 reported local reactions compared to 74.6% of participants age >65; after the second dose 90.3% of participants aged >18<65 reported local reactions compared to 83.8% of participants aged >65 (p. 24-27 (53)). More information about local reactions can be found in figures 9 and 10 in Appendix.

3.2.4. mRNA-1273 Systemic reactogenicity Systemic reactions lasted a mean of 2.9 and 3.1 days after first and second injection respectively and were, like local reactions, reported to a higher frequency for those >18<65 than those >65 (51) and were graded utilizing the same grading scale as local reactions.

The most common reported systemic reaction from mRNA-1273 overall was fatigue (65.3% after second dose), thereafter came headache (58.6%), myalgia (58%) and

13 arthralgia (42.8%). After the first dose, age group: >18<65 reported 57% systemic reactions compared to 48.3% reported from those age group: >65; after the second dose the same groups reported 81.9% versus 71.9% respectively. Incidents of systemic reactions differ in each group, but tendency of side effect prevalence is similar between groups where fatigue was the most common (67,6% for those in age group: >18<65; 58.3% for those in age group: >65) (p. 24-27 (53)). More statistics on systemic reactions can be seen in figures 11 and 12 found in Appendix.

Three deaths occurred in the placebo group (cause of death; one died from intraabdominal perforation, one died from severe systemic inflammatory syndrome (participant had chronic lymphocytic leukemia and diffuse bullous rash) and one died from cardiopulmonary arrest). Two participants died in the vaccine trial arm (one died from cardiopulmonary arrest and one died from suicide). There was no evidence in the trial of vaccine-associated enhanced respiratory disease (51).

3.2.5. mRNA-1273 Efficacy Counting from day one and through November 25th, 2020, in the placebo group there were 269 identified Covid-19 cases with an incident rate (IR) of 79.7 cases of Covid-19 per 1000 person-years (95% CI; 70.5-89.9). In the primary analysis there was a total of 196 cases of Covid-19 with 11 in the mRNA-1273 arm and 185 cases in the placebo arm. These numbers correspond to a 94.1% efficacy rate (RRR) of mRNA-1273 vaccine (95% CI; 89.3-96.8; P<0.001) for prevention of symptomatic Covid-19 as compared to placebo (51).

Assessing from 14 days after the first dose a total of 225 cases positive for Covid 19 was in the placebo arm and 11 in the mRNA-1273 group, corresponding to a vaccine efficacy (RRR) of 95.2% (95% CI; 91.2-97.4). Including participants that were SARS-CoV-2 positive at baseline there was 187 cases of Covid-19 in the placebo group and 12 in the mRNA-1273 group. Corresponding to a a vaccine efficacy (RRR) of 93.6% (95% CI; 88.6-96.5 (51).

Thirty participants had severe Covid-19 in the trial, all of which were in the placebo group. This corresponding to a vaccine efficacy (RRR) of 100% against severe Covid. One participant death amongst these 30 was attributed to Covid-19. The trial lacked sufficient data on mRNA-1273 efficacy on asymptomatic Covid-19 (51).

3.2.6 Articles showcasing mRNA-1273 against variants of concern A study from Xiaoying Shen et al., showed the B.1.1.7 variant being susceptible to mRNA-1273. The study utilized 11 blood samples from 29 days after first inoculation; and 29 samples from 28 days after second inoculation. The study was built on a pseudo virus neutralization assay. According to the authors, the B.1.1.7 variant of concern is not a variant prone to reduce vaccine efficacy or reinfection (54).

A correspondence article from Kai Wu, et al., also showed mRNA-1273 was effective against B.1.1.7 variant of concern utilizing eight blood samples from mRNA-1273 phase 1 trial. The study used a neutralization assay with a recombinant vesicular stomatitis virus (rVSV)-based SARS-CoV-2 pseudo virus model. The participants had taken the second dose one week before samples were collected. According to the authors, mRNA- 1273 was effective against the B.1.1.7 variant, they however observed a decrease in effectiveness against other variants including B.1.427/B.1.249, P.1 variant, and B.1.351 (55).

3.2.7 Adverse events from mRNA-1273 seen in practice An article from David M. Smadja, et al., the same article previously mentioned under BNT162b2, also looked at reported side effects on mRNA-1273. Between December 13th, 2o20 and March 16th, 2021, 361 734 976 people received Covid-19 vaccines. 2161 thrombotic events were reported in Vigibase databank and 325 were shared for mRNA- 1273. The authors make no claims of cause and effect or correlation between the events and the vaccine (50).

A case report by Sudhamshi Toom, et al., details a 36-year-old patient previously diagnosed with thrombocytopenia was administered mRNA-1273 two weeks before hospital admission. The patient presented with worsened thrombocytopenia and lesions and stayed in the hospital for four days but made a recovery. The authors note a possibly connection to the mRNA-1273 vaccine and worsened thrombocytopenia in existing patients (56).

3.3 AstraZeneca: AZD1222 Trial methodology The main published trial data from AstraZeneca differs from both Moderna and BioNtech-Pfizer in that it is an interim analysis of four different randomized, controlled clinical trials. These being COV001 (phase 1 / 2 in the UK); COV002 (phase 2 / 3 in the UK); COV003 (phase 3 in Brazil); and COV005 (phase 1 / 2 in South Africa). The interim vaccine efficacy was calculated using COV002 and whilst the vaccine safety measurement used data from all four trials, excluding COV005 for reactogenicity (57).

The trials were conducted for participants to either receive single dose AZD1222 as a single injection; two injections AZD1222 at a lower and then higher dose; AZD1222 at the same doses, and then all of which are compared to meningococcal vaccine (MENACWY) and/or saline solution as control. AZD1222 was originally meant to be a single-dose vaccine and the dosing regimen changed mid-trial due to efficacy concerns (57).

The reasoning for using another active vaccine as control was, according to AstraZeneca, that it minimizes the chances of participants accidentally unblinding and decreases chances of bias in reactogenicity and/or safety reporting. COV001 and COV002 used MENACWY as control; COV003 used MENACWY as a control in the first injection but placebo was compared to the booster shot; COV005 used saline solution as control for both first and second injection (57).

COV001 is a single blind phase 1 / 2 randomized clinical study of 1077 healthy participants aged 18-55 started on April 23rd, 2020 across five sites in the UK. Participants were randomly divided into a 1:1 assignment to either receive AZD1222 at a dose of 5 x 1010 viral particles (standard dose) or MENACWY as a control. Both are injected intramuscularly into the deltoid. A secondary dose (booster dose) was given 8 weeks after first dose (57).

COV002 is a phase 2 / 3 participant blinded randomized clinical study of 10,673 participants aged 18 to ≥70 which started on May 28th, 2020 across 19 sites in the UK. Participants were randomly divided into a 1:1 assignment to either receive a (accidental) low dose (LD) of AZD1222 (2.2 x 1010 viral particles) and thereafter standard dose (SD) (5 x 1010 viral particles) compared to two doses of the control MENACWY. During batch control research noted the first dose was of a lesser viral load (see above) and corrected the dosages for the second booster dose (57). The protocol was amended on June 5th, resulting in two groups in the trial. One to receive LD and thereafter SD compared to control; and one to receive two SD compared to control. COV002 included HIV patients but these were excluded from the pooled safety and efficacy analysis. Booster doses were given a minimum of 4 weeks after the first dose but upwards of 12 weeks after (57).

COV003 is a single blind randomized, phase 3 study of 10,002 participants aged 18 and above in Brazil which began on June 23rd, 2020. Participants were randomly assigned in a 1:1 to either receive two doses of AZD1222 (3.5-6.5 x 1010 viral particles) or two control shots. Administration was at most 12 weeks a part with 4 weeks being the goal (57).

COV005 is a single blind phase 1 / 2 double blind, randomized trial of 2,096 participants aged 18-65 in South Africa which began on June 28th, 2020. Participants were divided into a 1:1 grouping to either receive two doses of AZD1222 (3.5-6.5 x 1010 viral particles) at 4 weeks a part or placebo (saline solution) (57).

Inclusion and exclusion criteria were similar across all studies except age. Variation mattered most due to the studies being in separate phases. Overall inclusion criteria were to be of good health (i.e., no comorbidities OR stable chronic conditions) in the age spans sought after, willingness to cooperate with all study requirements (including full access to patient journal) and refraining from donating blood. Exclusion criteria included pregnancy, history of angioedema or anaphylaxis, pregnancy, amongst others. Full information about inclusion and exclusion criteria can be seen in AstraZeneca Supplementary Appendix 2 on under each trial’s criteria segment (57).

Participants were observed for 60 minutes (±30 minutes) after the first dose and for 15 minutes after the booster dose, with an on-call physician to report findings (p. 518 (58)). Participants will also undergo a follow-up period of 12 months after the last dose (p. 112 (58)).

Primary study endpoint was to compare efficacy of AZD1222 against confirmed Covid- 19 (57). Confirmation criteria for Covid-19 can be seen in table 5 in Appendix.

Secondary study endpoint was to evaluate safety, reactogenicity and tolerability of AZD1222 and efficacy of AZD1222 against severe Covid-19 (57). Confirmation criteria for severe Covid-19 can be seen in table 6 in Appendix.

3.3.1. AZD1222 Trials Participant information Between April 23rd, 2020 and November 4th, 2020, a total of 23,848 participants were recruited and subsequently vaccinated across the four studies. 11,636 participants (from COV002 and COV003) met the criteria to be included in the primary analysis; 5,807 received two doses of AZD1222 and 5,829 received two doses of control group (64). Common exclusion criteria for drop-off from efficacy analysis included non- enrollment in efficacy cohort and baseline seropositivity results unavailable (p. 5 (59).

In total, at baseline across all studies used for efficacy evaluation, 10,218 were aged 18- 55 (87.8%) with those aged 56-69 making up 974 participants (0.84%) of the total and those aged ≥70 making up 444 (0.38%) of the total. 7,045 (~60%) of participants were female and 4,951 (~40%) of participants were male (57).

In total, at baseline across all studies used for efficacy evaluation, 9,625 (82.7%) were white; 479 (4.1%) were black; 517 (4.4%) were Asian; 927 (7.9%) were mixed; and 88 (0.7%) were other. Participants could be included into one or more categories (57).

3.3.2. AZD1222 Safety Reporting of local and systemic reactions were not reported in the interim analysis from AstraZeneca (57). Reactogenicity data has therefore been assembled from an EMA report (60). A total of 23,745 participants were evaluated and documented for safety. 12,021 participants of these got at least one dose of AZD1222 compared to 11,724 in control (including saline solution placebo). Among the 12,021 participants, 1 standard dose (SD) was administered to 10,069 participants; LD was administered to 1,947

16 participants. Two-dose regimen was administered to approximately two thirds of participants. COV005 group was not included in the pooled reactogenicity subset as their reactions were solicited with different methods (pages 124-125, (66). The final pooled analysis of COV001, COV002 and COV003 was 18,002 participants (table 33 (60)). The summary of both local and systemic adverse events utilizes three groups; AZD1222 group; control A (MENCAWY) and control B (MENCAWY + saline placebo) as the reactogenicity subset sits at around 3300 participants (p. 125-132, (60)).

3.3.3. AZD1222 Local reactogenicity Local reactions (i.e., at and around injection site) were graded after a 4-grade severity scale from 1) does not impact everyday activity; 2) interferes with everyday activity; 3) prevents everyday activity or 4) requires emergency room visit or hospitalization (p. 526-527 (59)).

The mean duration of local reactions after the first injection from AZD1222 was 3.3 days compared to 2.3 days in the control group; after the second injection the same groups reported a duration of 2.3 days and 2.0 days, respectively. Local reactions were tracked for seven days after each vaccination (p. 125-126 (60)).

The most common local reaction (any severity) was local tenderness after the first dose, of which 72,2% in the AZD1222 group reported it compared to 49.1% in control A and 32.7% in control B. After the second dose 51.0% reported local tenderness in the AZD1222 group compared to 42.5% in control A and 4.3% in control B (table 33, p. 127 (60)).

After the first dose, 51.6% in the AZD1222 group reported local post-injection pain. This compared to 30.9% in control A and 56.1% in control B. After the second dose the same three groups reported 26.9%, 24.0% and 21.7% local post-injection pain respectively (table 33, p. 127, (60)).

Other less reported local reactions (any severity) at their highest were redness (2.6% in AZD1222 after first injection), warmth (15.8% in AZD1222 group after first injection), itching (5.8% in AZD1222 group after first injection), swelling (3.1% in Control B after second injection) and induration (2.6% in AZD1222 group after first injection) (table 33, p. 127, (60)). More statistics on local reactions can be seen in figure 13 found in Appendix.

3.3.4. AZD1222 Systemic reactogenicity Systemic reactions were graded after a 4-grade severity scale from 1) mild; 2) moderate; 3) severe and 4) potentially life threatening (p. 528-529 (59)). Systemic reactions overall from AZD1222 lasted a mean duration of 2.8 days after the first dose (2.6 days overall in control) and 2.3 days after the second dose (compared to 2.5 days overall in control). The most frequent reported systemic reaction was fatigue (59.1% after the first AZD1222 dose), thereafter came headache (54.4% after first AZD1222 dose), muscle pain (45.4% after first AZD1222 dose), malaise (40.8% after first AZD1222 dose), feverishness (31.7% after first AZD1222 dose), joint pain (24.6% after first AZD1222 dose), nausea (20.2% after first AZD1222 dose) and fever (9.1% after first AZD1222 dose). Vomiting was reported from 1.4% after the first AZD1222 dose (table 34, p. 129- 132, (60)).

Prevalence of systemic reactions overall decreased after the second dose compared to after the first one. After the first injection, 79.0% in the AZD1222 group reported any systemic reaction compared to 56.0% after the second injection. Participants aged ≥65 reported less systemic reactions than those ≤65 (p. 170 (60)) however there are no specific figures mentioned. 17

More statistics on systemic reactions can be seen in figure 14 found in Appendix

<1% of participants from the safety population reported any serious adverse effects and less than 0.1% participants reported a serious adverse effect that was related to the vaccine according to investigators. In the AZD1222 group there was reported; one case of pyrexia, one case of elevated C-reactive protein (though this was later retracted to not be related to the vaccine), and one case of transverse myelitis. In the control group there were two cases; one transverse myelitis and one hemolytic anemia case. There was also an imbalance of seven nervous system disorders reported in the AZD1222 group compared to four in the control (p. 135, (60)).

Six deaths were reported in the trial, two in the AZD1222 group and four in control. None were related to the trial vaccine according to investigators (p. 135, (60)).

3.3.5. AZD1222 Efficacy Only COV002 and COV003 were pooled for the efficacy analysis in the interim analysis of AZD1222 (57), p. 77 (59)). The main reasoning being they were both in phase 2 / 3 with similar age majorities across both studies whilst also containing similar inclusion and exclusion criteria (p. 77, (60)).

There were 131 cases of symptomatic Covid-19 in the LD/SD participants partaking in the efficacy evaluation; 30 in the AZD1222 arm and 101 in the control arm. Resulting in a vaccine efficacy (RRR) of 70.4% (95.8%CI: 54.8-80.6). In participants who received two SD the vaccine efficacy (RRR) was 62.1% (95% CI: 41.0-75.7) and participants who first received LD and thereafter SD the vaccine efficacy was higher, coming in at 90.0% (RRR) (57).

There were zero severe Covid-19 cases in the AZD1222 arm compared to two in the control arm (one case >21 days after the first dose and ≤14 days after the second dose; one case ≥14 days after the second dose. Resulting in a 100% efficacy (RRR) against severe Covid-19 (57).

An updated report containing clinical efficacy data from all four trials (COV001, COV002, COV003 and COV005) published on March 6th, 2021, included 17,178 participants in the efficacy analysis. There were 332 cases of symptomatic Covid-19 occurring in the trial ≥14 days after the second injection of AZD1222; 84 positive cases occurred in the AZD1222 arm and 248 in the control arm leading to an efficacy (RRR) of 66.7% (95%CI: 57.4-74.0). In participants receiving two SD there were 74 cases and 197 in the control group, leading to a vaccine efficacy (RRR) of 63.1% (95% CI: 51.8-71.7). In the LD/SD arm there were 10 cases of symptomatic Covid-19 and 51 cases in the control arm, leading to a vaccine efficacy (RRR) of 80.7% (95% CI: 62.1-90.2) for prevention of symptomatic Covid-19 as compared to placebo (61).

There were 130 cases of asymptomatic infection ≥14 days after the second injection (COV002 cohort only). Vaccine efficacy (RRR) calculated to be 22.2% (95% CI: -9.9- 45.0). Participants who received two SD showed no evidence for protection against asymptomatic Covid-19 with a calculated efficacy (RRR) of 2.0% (95%CI: -50.7-36.2). Participants receiving LD/SD showed a vaccine efficacy against asymptomatic Covid- 19 of 49.3% (RRR) (95% CI: 7.4-72.2) (61).

AZD1222 showed no evidence of waning efficacy against symptomatic Covid-19 three months after the second injection (61).

3.3.6. AZD1222 against variants of concern An original article published on March 16th, 2021 from Shabir A. Mahdi et al., funded by the Bill and Melinda Gates foundation had a primary endpoint to assess efficacy and safety of AZD1222 in HIV-negative participants in South Africa from June 24th, 2020 and November 9th, 2020 in multicenter, double blind randomized controlled trial. Participants were aged ≥18<65 and randomized in a 1:1 ratio to either receive two doses of AZD1222 (5x1010 viral particles) or placebo (0.9% sodium chloride solution) 21-35 days between doses. It was a secondary trial endpoint to evaluate the efficacy against the B.1351 variant of concern. 39 cases of the variant were reported in the trial and the trial found little to no evidence that AZD1222 protected against B.1351 with a vaccine efficacy of 10.4% (95% CI: -76.8- 54.8) (62).

3.3.7. Adverse events from AZD1222 seen in practice: Case series An original article from Nina H. Schultz et al., reported five patients presenting with venous thrombosis and thrombocytopenia 7-10 days after receiving the first dose of AZD1222. All of the five patients were healthcare workers aged 32-54 years old and all of them had high levels of IgG antibodies to platelet 4-polyanion complexes (PF4), measured by ELISA, but no previous exposure to heparin. Four out of five patients experienced severe venous thromboembolism and four out five also experienced severe cerebral venous thrombosis with intracranial hemorrhage. Three out of five patients died related to these incidents. The authors propose that these 5 cases in the report present a rare form of vaccine-induced immune thrombotic thrombocytopenia (VITT) (63).

An original article from Andreas Greinacher et al., present eleven patients from Germany and Austria that experienced thrombosis or thrombocytopenia between 5 and 16 days after AZD1222 vaccination. Nine out of eleven patients were women with a median age of 36. Nine patients had cerebral venous thrombosis, 3 had splanchnic-vein thrombosis, 3 had pulmonary embolism(s) and four had other thromboses. Six out of eleven patients died. All patients had high levels of IgG antibodies for PF4 as measured by ELISA but none had previously received heparin. The authors propose a possible rare connection to AZD1222 and these conditions (VITT) (64).

An original article from Marie Scully et al., conducted a study in 23 patients after being referred to a hematologist for suspected VITT. The median age of patients was 46. Fourteen was female. No patient had previous medical condition and were all previously fit by the referring hospitals. All patients had received the first dose of AZD1222 between 6 and 24 days before the study started. Thirteen patients had clinical features concurrent with cerebral venous thrombosis. Four had pulmonary embolism (one with DVT). Several other thrombolytic events are mentioned in the study. Within the entire study, seven patients died. 22/23 patients tested positive for IgG antibodies for PG4 as measured by ELISA. These authors also propose a possible link between AZD1222 and rare VITT (65).

3.3.8. Adverse events from AZD1222 seen in practice: Cohort A Danish-Norwegian population-based cohort study from Anton Pottegård et al., looked into people aged 18-65 from the two countries that received their first AZD1222 dose between February 9th 2021 to March 11th 2021. 148,792 people in Denmark and 132,372 people from Norway were included in the study, a total of 281,264 participants. The study utilized data obtained from Danish and Norwegian healthcare registries and the cohort consisted of anyone receiving their first dose of AZD1222. Exclusion criteria were those <18, >65 and those who immigrated to the countries within 365 days before their first inoculation. The study’s main outcome looked at hospital contact for incidents related to arterial events; venous thromboembolism, thrombocytopenia or coagulation disorder(s), and bleeding, all within 28 days after the first dose (66).

The results were then compared to the expected occurrence of these events in the general population. 83 arterial events were observed versus the 86 expected (resulting in a standardizes morbidity ratio of 0.97 (95% CI: 0.77-1.20). Within this group the rate of intracerebral hemorrhage increased and the standardized morbidity ratio of 2.33 (1.01-4.59) representing to 1.7 (95% CI: 0.0.6) excess events per 100,000 vaccinations. An increase in venous thromboembolism was also seen in the study; 59 events compared to the 30 expected. This corresponding to a standardized morbidity ratio of 1.97 (1.50-2.54) and 11 (5.6-17.0) excess events per 100,000 vaccinations. They also witnessed increases in pulmonary embolisms (3.4 excess events per 100,000 vaccinations), and any thrombocytopenia/coagulation disorders (3.0 excess events per 100,000 vaccinations) amongst others (66).

The authors note that the evidence of excess risk exists, but overall absolute risk remained small and vaccination benefits outweigh the risk (66).

Table 5. Summary table of vaccine safety and efficacy parameters and study demographics. BNT162b2 (47) mRNA-1273 (51) AZD1222 (57,60) Participants (n) 37,706 28,207 23,745 Median age 52 51.4 n.a RRR 95.1% 94.1% 66.7% Most common Pain at injection Pain at injection Tenderness (72.2%) local reaction site (83%) site (89.9%) Second common Swelling (7%) Lymphadenopathy Pain at injection site local reaction(s) and redness (7%) (16.2%) (51.6%) Most common Fatigue (59%) Fatigue (67.6%) Fatigue (59.1%) systemic reaction Second common Headache (52%) Headache (62.8%) Headache (54.5%) systemic reaction Third common Muscle pain Muscle pain Muscle pain (45.4%) systemic (37%) (61.6%) reaction

4. Discussion 4.1 Result discussion 4.1.1 Prevention of Covid-19/severe Covid-19 and vaccine efficacy The first question this paper set out to answer was how effective the vaccines in question are against protection from Covid-19 and/or severe Covid-19. This question is closely related to the second question in this paper, that is; Which vaccine expresses the highest efficacy? Regarding these questions being closely related (i.e., “efficacy” being tied to protection from Covid-19 and/or severe Covid-19) they will be tried to be answered together.

In each study the metric used to measure vaccine efficacy was relative risk reduction (RRR). RRR is a useful metric when comparing between groups where one is exposed to the treatment (i.e., the vaccine) and the other is exposed to placebo (saline solution) or active control (as was the case for majority of AZD1222 trials) to summarize the evidence of efficacy. However, it is not the best, or at least not the only, metric for measuring definitive absolute effect and can often be misleading if reported alone. Absolute Risk Reduction (ARR) is another metric utilized to assess the efficacy of an intervention. ARR showcases the absolute efficacy of a treatment in real-world application but is easily susceptible to changes in the underlying event-rate and background risk in each trial. Likewise, neither trial published information about the Number Needed to Treat (NNT), which indicates how many patients needs an intervention to prevent one additional harmful or bad outcome.

An article by Robert B. Brown calculated based on the published trials from BioNTech- Pfizer and Moderna that the ARR for each vaccine would be 0.7% (BNT162b2) and 1.1% (mRNA-1273). In the same article Brown also calculate the NNT, reported as Number Needed to Vaccinate (NNV), to be 142 for BNT162b2 and 88 for mRNA-1273 (67). An article by Piero Olliaro et al., calculated based on published data by AstraZeneca that the ARR for AZD1222 is 1.3% and the NNV is 78 (68).

Several reasons exist for not reporting ARR or NNV. A major reason one could speculate can be that it is hard to interpret for most people and it is often a very low number, which can be interpreted as the vaccines being ineffective since big numbers often is seen as more impressive. Indeed, big numbers are often seen as more attractive to report within medical literature. However, solely publishing the RRR on its own gives a misleading impression of efficacy given that the RRR does not account for background risk associated with each study. For this reason, the RRR is hard to interpret since it can be the same regardless of if the ARR is big or small, if the incremental difference remains the same. As such the ARR is a more effective means of communicating real-world effect, especially when accompanied by the RRR. The NNV was also absent from each trial, which is disheartening given that NNV can often be easily understood by most people and could be especially useful when looking at a population undergoing vaccination.

The trials themselves showcased prevention of Covid-19 to be high, with very few cases reported of Covid-19 in each study group compared to placebo (or active control for AZD1222). The most substantial metric of efficacy that the studies showcase however one could argue is the lack of deaths from Covid-19 in any of the intervention groups. These papers not only showcases that the vaccines are highly effective in prevention of Covid-19; but that if Covid-19 infection were to manifest the chances of dying are highly unlikely. A big positive for AZD1222 is the fact that they displayed efficacy for asymptomatic infection, however the efficacy was not very high. AZD1222 did however also display two major differences in efficacy with its SD/SD and LD/SD dosing regimen, and this could owe to some underlying mechanism in of which the immune system better “learns” and can tackle an oncoming SARS-CoV-2 infection if it is first trained at a lower dose and then titrated up. This is merely speculation however, and full speculative analysis is outside the scope of this paper.

Regarding drawing comparisons between each vaccine efficacy however, difficulties arise. Each study was conducted in different countries or continents (though Moderna and BioNTech-Pfizer were primarily in the USA), likewise the underlying event rate of Covid-19 differ in each nation during the trial period (as is indicated by the ARR). Further on, two of the vaccines were mRNA vaccines at different dosages and one was an adenoviral vector. Another drawback for drawing comparisons is the differences in protocols for active control and placebo, whereas both Moderna and BioNTech-Pfizer utilized placebo only, AstraZeneca utilized active control primarily and placebo secondarily, making comparisons exceedingly difficult.

The studies did however have very similar definitions, protocol, and testing for Covid- 19 and/or severe Covid-19, indeed they were almost identical between the trials.

All three vaccines lack long-term efficacy reporting but none has shown waning support in the months following vaccination according to each paper.

To bring another matter into the mix is the fact that only BNT162b2 is approved for persons aged <18, with it recently being approved by the FDA for ages 12-15 in the USA (69). The full clinical trial data however is, as of writing this, not published by BioNTech nor Pfizer (70).

Moderna are in the trial phase of conducting clinical trials for adolescents to be approved the use of mRNA-1273. This is however an ongoing clinical trial in the USA and is expected to be completed in 20222 (71).

AZD1222 does not have any clinical data on its use in adolescents.

Overall, one cannot explicitly state, or at least should be very careful to state, which vaccines have the highest efficacy compared to another given major differences in study protocols. This falls in line with another systemic review which tried to compare vaccine efficacy and deemed it, as of yet, impossible (72). All vaccines showcased good protection against severe Covid-19. Zero participants in trial arm of any of the vaccines died from severe Covid-19.

One can however confidently say that the vaccines, regardless of which mentioned, showcase high efficacy against Covid-19 and severe Covid-19. On their own metrics, the highest RRR belongs to BNT162b2; the highest ARR belongs to AZD1222 and the lowest NNV also belongs to AZD1222. One also must bring trust into government agencies and regulatory bodies that agree that these vaccines are highly effective and safe to be administered to the masses.

4.1.2 Vaccine side effects The third question this paper set out to answer was which was the most common side effect from the vaccines and which vaccine expressed the fewest side effect.

Side effects from the vaccines were usually mild to moderate in severity and the overwhelming majority of reactions lasted a handful of days before passing. A quick rundown of the most common side effects can be seen in Table 5, which showcase that all vaccines top local and systemic reactions were identical (though exact prevalence in studio population varied). Indeed, all vaccines in their respective trials showcased overall high safety with reactogenicity being mild. Most common local reactions across all vaccines were post-injection pain, tenderness, and redness. All 0f whom lasted a few days. Likewise, systemic reactions were overall mild to moderate in nature with the most common reactions being fatigue, myalgia (or “muscle pain”), headache(s) and arthralgia (or “joint pain”), these too lasted a few days. In general, the odds of receiving any reaction were high; but the reactions themselves were of modest nature, indicating the vaccines were well-tolerable compared to placebo and/or active control.

Surprisingly, participants aged above 55 and 65 in each trial reported overall lesser reactions after both first and second dose regardless of vaccine. This could possibly be linked to more mature and robust immune responses not going overboard when faced with a pathogen; or it could be a lack of immune response in older participants not engaging as hard as younger participants. These theories and underlying mechanism would be fascinating to study for future research.

Local and systemic reactions between trials also utilized a near-identical protocol for assessment of reaction severity and the definitions of each reaction was also near- identical. This is a major positive in trying to establish a comparison and compare reactions rates between vaccines. mRNA-1273 and BNT162b2 also displayed reactogenicity in similar age brackets, with BNT162b2 having two age brackets (16-55 and >55) and mRNA-1273 also having two age brackets (18-65 and >65). This is also helped by the fact that, whilst different in dosages and exact mechanism, the vaccines themselves are within the same pharmacological group, making it easier (though not an exact science) to compare. Unsurprisingly to this fact however, given the major similarities between these two mRNA vaccines, they also share very similar prevalence of local and systemic reactions.

In general, local reactions for BNT162b2 went down after the second dose, whilst systemic increased after the same dose. In the instance of mRNA-1273, both local and systemic reactions increased after the second dose.

AZD1222 on the other hand showcased that both systemic and local reactions went down after the second dose, this in direct contradiction to the two mRNA vaccines which in one way or the other increased the prevalence of said reactions. This data one can speculate owes to the differences in mechanism of action between the vaccines and different delivery methods instilling differences in immune response both on a local and systemic level. However, this is merely conjecture and full speculative analysis remains outside the scope of this paper. Likewise, that analysis would be hard to derive definitive answers from given that AZD1222 did not report reactogenicity between age brackets, and only reported so between the intervention group and controls and/or placebo. It is also for this difference in study protocol that one cannot truly compare AZD1222 reactions to mRNA vaccines given that the active control in the AZD1222 study inherently displays reactogenicity in of itself, muddling the waters in comparison. Also, even though AZD1222 showcase overall lesser prevalence of reactions in general, it was also a compilation of phase 1,2 and 3 trials (compared to either parallel phase 2 or sole phase 3 trial), making comparisons even more difficult.

Accompany this with the fact that AZD1222 has been expelled from multiple vaccination programs in the EU due to safety concerns regarding thrombolytic events (73), one would be hard pressed to state that AZD1222 was the vaccine with least side effects solely based on the original papers.

Bringing the matter to a rest; all vaccines showcase high tolerability and safety, and even though comparisons remain difficult, the mRNA vaccines could be the ones showcasing the highest overall tolerability and safety, with possibly BNT162b2 from BioNTech- Pfizer coming in with the lowest overall adverse reactogenicity. This is however mostly based on its own paper and in relation to similarities between mRNA-1273 and not compared to AZD1222, as such it should not be taken as a definitive answer and instead seen as conjecture and not a conclusion.

4.1.3 Vaccine efficacy against SARS-CoV-2 variants Big clinical data and RCTs on SARS-CoV-2 variants remains absent. Articles mentioned in this paper for BNT162b2 and mRNA-1273 are in-vitro (49,54,55) and as such are very hard, if not impossible, to infer to in-vivo application.

AZD1222 did have a trial done in South Africa by Shabir A. Mahdi et al., (62) where the RCT did evaluate vaccine efficacy against variant B.1351. This was however a relatively small-scale study and unfortunately its findings indicate poor efficacy.

According to a vaccine update from Moderna on January 25th, 2021, mRNA-1273 produces neutralizing titers against all, at the moment, key emerging variants of concern (B.1.1.7 and B.1.351) (74). This clinical data is however yet to be released from Moderna.

Likewise, a press release from Pfizer details that a new trial of 2,260 adolescents aged 12-15 years old had 18 cases in the placebo group (N=1,129) and none in the BNT162b2 group (N=1,131) with strong immunogenicity shown in support of the vaccine’s efficacy (75). The full clinical trial is yet to be published.

Unfortunately, the question of vaccine efficacy against SARS-CoV-2 variants of concern remains unanswered due to a lack of sufficient clinical data.

4.1.4 Future research There are multiple Covid-19 vaccines in development around the globe and the underlying science that drives mRNA and adenovirus vector vaccines showcase a good platform do drive further research future vaccination programs. mRNA vaccines show promise in future areas such as Malaria, Tuberculosis and Cystic Fibrosis (76). Adenoviral vector vaccines show promise within HIV amongst others (77).

4.1.5 Method discussion This paper has several limitations that are worth including. First and foremost, it is of limited nature and scope due to the time constraints and quantitative restrains (i.e., how many articles can be included) associated with a work of this size. This lends into the fact that due to limited time and budget one cannot cover vast amounts of literature and faces the risk of missing important pieces of information and articles.

Secondly, an inherit disadvantage is to the researcher itself. Due to searching on their own due diligence and after their own criteria, one can miss out on important articles merely to the fact that inherit bias exists and setting arbitrary rules (i.e., which words to include and exclude when searching), this risks articles missing out on being included.

Thirdly, which databases one chooses to utilize can also have a big impact and resorting to the one covered in this paper (PubMed) and two journals (The Lancet and NEJM) also increases the risk of failing to find relevant literature.

However, these downsides can be counteracted with the fact that all articles utilized in this paper were published in major journals. Likewise, the articles quoted, especially the main papers on the vaccines, are of exceedingly high quality. This paper also contains a complete and traceable method of which it is based on, increasing its relevancy, accuracy, and trustworthiness.

4.2 Conclusion Despite its limitations and disadvantages, this paper can showcase that the three first Covid-19 vaccines approved in the EU (BNT162b2; mRNA-1273 and AZD1222) present overall high efficacy and safety for their approved ages. This paper cannot state which

24 vaccine holds the highest efficacy rating compared to each other directly, but that the vaccines overall showcase high efficacy and safety tolerability. Future research is needed to assess efficacy for Covid-19 variants of concern and efficacy and safety for adolescents. This paper was not able to answer these questions.

5. Acknowledgements I want to thank my supervisor Martin Bäckström and examiner Maria Sjölander for good, solid feedback and concrete suggestions guiding this paper to its final form.

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Appendix Figures and tables

Abbreviations: Muscle Pain (MP) Joint Pain (JP) Antipyretics (AP) Significant Adverse Reaction (SAR)

BioNTech-Pfizer:

Data and formatting shown in table 4-7 and figures 1-9 are derived from phase 2 / 3 trial published by Pfizer (47-48).

Table 1. Covid-19 confirmation criteria. Participant must have positive PCR-test for SARS-CoV-2 and: ≥1 symptom (additional symptoms within 4 days will be considered as part of a single illness):

Fever (>38°C) New or increased cough New or increased shortness of breath New or increased muscle pain Chills New loss of taste or smell Diarrhea Vomiting Sore throat Fatigue Headache Nasal congestion or runny nose Nausea Definitions and formatting derived from Pfizer Study Protocol (p. 373-374 (48)).

Table 2. Severe Covid-19 confirmation criteria. Confirmed Covid-19 as per previous criteria with ≥1 of the following:

Clinical signs at rest indicative of sever systemic illness (≥30 breaths/minute; heart rate ≥125 bpm; SpO2 ≤93% on room air at sea level or PaO2/FiO2 <300 mm Hg) Respiratory failure Evidence of shock (SBP <90 mm Hg, DP <60 mm Hg, or requiring vasopressors) Significant and acute renal neurological or hepatic dysfunction Admission to an ICU Death Definitions and formatting derived from Pfizer Study Protocol (p. 373-374 (48)).

Age group 16-55: Dose 1 100 90 83 80 70 60 50 40 30 % of % Participants 20 14 5 6 10 1 0 0 BNT126b2 Placebo BNT126b2 Placebo BNT126b2 Placebo Post-injection pain Redness Swelling

Mild Moderate Severe Grade 4

Figure 1. Local reactions in age group 16-55 after first dose.

Age group 16-55: Dose 2 100 90 80 78 70 60 50 40

30 % of % Participants 20 12 10 6 6 1 0 0 BNT126b2 Placebo BNT126b2 Placebo BNT126b2 Placebo Post-injection pain Redness Swelling

Mild Moderate Severe Grade 4

Figure 2. Local reactions in age group 16-55 after second dose.

Age group >55: Dose 1 100 90 80 71 70 60 50 40

30 % of % Participants 20 9 10 5 7 1 1 0 BNT126b2 Placebo BNT126b2 Placebo BNT126b2 Placebo Post-injection pain Redness Swelling

Mild Moderate Severe Grade 4

Figure 3. Local reactions in age group >55 after first dose.

Age group >55: Dose 2 100 90 80 70 66 60 50 40

30 % of % Participants 20 8 7 7 10 1 1 0 BNT126b2 Placebo BNT126b2 Placebo BNT126b2 Placebo Post-injection pain Redness Swelling

Mild Moderate Severe Grade 4

Figure 4. Local reactions in age group >55 after second dose.

Colors of figures 6-9 both represent body temperature and grading scale according to severity as seen in figures 1-4.

Figure 5. Systemic reactions in age group 16-55 after first dose.

Figure 6. Systemic reactions in age group 16-55 after second dose.

Figure 7. Systemic reactions in age group >55 after first dose.

Figure 8. Systemic reactions in age group >55 after second dose.

Moderna: Data and formatting shown in table 8-10 and figures 11-15 are derived from phase 3 trial published by Moderna (51-53).

Table 3. Covid-19 confirmation criteria. Participant must have positive PCR test and for SARS-CoV-2 and participant must experience:

≥2 systemic symptoms: Fever (≥38 °C) Chills; Myalgia; Headache; Sore throat; New olfactory and taste disorder(s);

≥1 of the following respiratory symptoms: Cough; Shortness of breath/difficulty breathing;

Clinical or radiographical evidence of pneumonia Definitions and formatting derived from Moderna Study Protocol (p. 142-146 (52)).

Table 4. Severe Covid-19 confirmation criteria. Confirmed Covid-19 as per previous criteria with ≥1 of the following:

Clinical signs at rest indicative of sever systemic illness (≥30 breaths/minute; heart rate ≥125 bpm; SpO2 ≤93% on room air at sea level or PaO2/FiO2 <300 mm Hg)

Respiratory failure or Acute Respiratory Distress Syndrome (ARDS) Evidence of shock (SBP <90 mm Hg, DP <60 mm Hg, or requiring vasopressors)

Significant and acute renal neurological or hepatic dysfunction

Admission to an ICU Death Definitions and formatting derived from Moderna Study Protocol (p. 142-146 (52)).

Figure 9. All local reactions seen across all groups from mRNA-1273 compared to placebo.

Figure 10. All local reactions seen across all groups from mRNA-1273 compared to placebo in age groups 18-65 and >65.

Figure 11. All local reactions seen across all groups from mRNA-1273 compared to placebo.

Figure 12. All systemic reactions* seen across all groups from mRNA-1273 compared to placebo in age groups 18-65 and >65. *Vomiting includes nausea.

AstraZeneca: Data and formatting shown in table and figures are derived from phase 1/2/3 interim analysis and/or study protocols published by AstraZeneca (57-59) and EMA (60):

Respiratory Symptom Non-respiratory Symptom New onset of coughing Fever and/or feeling feverish (≥37.8°C or defined subjectively. Regardless of use of any antipyretics) New shortness of breath (includes Myalgia breathlessness or having trouble breathing) New rapid breathing Chills Sore throat Loss of appetite Nasal congestion Tiredness (includes fatigue or feelings of weakness) Runny nose Diarrhea Loss of smelll Loss of taste Headache Nausea or vomiting Table 5. Symptoms of suspected Covid-19 (AstraZeneca Supplementary Appendix 2: page 487 (58)).

Severity of Covid-19 Definitions At least one: - Fever (measured subjectively or objectively regardless of antipyretics) - New cough - ≥2 Covid-19 respiratory and/or non-respiratory symptoms as seen Mild in Table 11.

AND

- Does not meet any criteria for Moderate or Severe Covid-19 as seen below One or more: - Fever ((≥37.8°C) + any two Covid- 19 symptoms as seen in Table 11 for ≥3 days (need not to be continuous days)

- High Fever ((≥38.4°C) for ≥3 days (need not to be continuous days)

Any evidence of lower respiratory tract infection: Moderate - Shortness of breath (includes breathlessness/difficulty breathing) with/without exertion 41

- Tachypnea (20-29 breaths/min at rest) - SpO2 <94% on room air - Abnormal chest CT/x-ray consistent with pneumonia or lower respiratory tract infection - Adventitious sounds on lung auscultation Severe One or more: - Tachypnea ≥30 breaths per minute at rest - SpO2 <92% on room air OR PAO2/FiO2 <300 - Mechanical ventilation OR ECMO - One or more major organ system failure (e.g., renal, hepatic or cardiac) - High flow oxygen therapy, CRAP or NIV (e.g., CRAP/BiPAP) Table 6. Definitions of Covid-19 severity (AstraZeneca Supplementary Appendix 2: page 488 (58))

Figure 13. Local reactogenicity of AZD1222 compared to Control A&B. Data from EMA and AstraZeneca (57,60,61)

Figure 14. Systemic reactogenicity of AZD1222 compared to Control A&B. Data from EMA and AstraZeneca (57,60,61)

Department of Integrative Medical Biology Umeå University SE-901 87 Umeå, Sweden www.umu.se