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COVID-19 VACCINES

The document discusses various COVID-19 vaccine candidates and types. It describes four main types - whole virus vaccines, protein subunit vaccines, nucleic acid vaccines, and viral vector vaccines. For each type it explains how they work, potential advantages and disadvantages, and examples of vaccines that use each approach. It provides details on some of the leading COVID-19 vaccine candidates in clinical trials, including Pfizer/BioNTech, Moderna, Oxford/AstraZeneca, and discusses the clinical trial process, recommendations for distribution, and efforts to scale up production and distribution of approved vaccines.

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COVID-19 vaccines Prof.Amal Sayed IPC Director CUH
Vaccine prospects The COVID-19 candidates, like all vaccines, essentially aim to instruct the immune system to mount a defense, which is sometimes stronger than what would be provided through natural infection and comes with fewer health consequences.
COVID-19 vaccine types in development Candidates in Clinical Phases I-III
Vaccines Development To do so, traditional vaccines use the whole coronavirus, but in a killed or weakened state. Others use only part of the virus— whether a protein or a fragment. Some transfer the instructions for coronavirus proteins into an unrelated virus that is unlikely or even incapable of causing disease. Finally, cutting-edge vaccines under development rely on deploying pieces of the coronavirus’s genetic material, enabling our cells to temporarily make coronavirus proteins needed to stimulate our immune systems.
COVID-19 vaccine types in development
There are more vaccine candidates simultaneously in the pipeline for COVID-19 than ever before for an infectious disease. All of them are trying to achieve the same thing – immunity to the virus, and some might also be able to stop transmission. They do so by stimulating an immune response to an antigen, a molecule found on the virus. In the case of COVID-19, the antigen is typically the characteristic spike protein found on the surface of the virus, which it normally uses to help it invade human cells.
THE FOUR MAIN TYPES OF COVID-19 VACCINE There are four categories of vaccines in clinical trials: WHOLE VIRUS PROTEIN SUBUNIT VIRAL VECTOR NUCLEIC ACID (RNA AND DNA) Some of them try to smuggle the antigen into the body, others use the body’s own cells to make the viral antigen.
Whole viruses vaccines Many conventional vaccines use whole viruses to trigger an immune response. There are two main approaches. Live attenuated vaccines use a weakened form of the virus that can still replicate without causing illness. Inactivated vaccines use viruses whose genetic material has been destroyed so they cannot replicate, but can still trigger an immune response.
Knocked-out whole virus Uses a non-infectious form of the coronavirus that can no longer cause full-blown disease but can still provoke an immune response. The virus can either be fully inactivated or weakened. These modes are considered the most classic ways to make vaccines.
Both types use well-established technology and pathways for regulatory approval, but live attenuated ones may risk causing disease in people with weak immune systems and often require careful cold storage, making their use more challenging in low-resource countries. Inactivated virus vaccines can be given to people with compromised immune systems but might also need cold storage.
Whole virus vaccines Both are tried and tested vaccination strategies, which form the basis of many existing vaccines – including those for yellow fever and measles (live attenuated vaccines), or seasonal influenza and hepatitis A (inactivated vaccines). Bacterial attenuated vaccines also exist, such as the BCG vaccine for tuberculosis Live attenuated vaccines use a weakened form of the virus, which can still grow and replicate, but does not cause illness. Inactivated vaccines contain viruses whose genetic material has been destroyed by heat, chemicals or radiation so they cannot infect cells and replicate, but can still trigger an immune response.
ADVANTAGES AND DISADVANTAGES OF LIVE ATTENUATED VACCINES
ADVANTAGES AND DISADVANTAGES OF INACTIVATED VIRUS VACCINES
HOW DO WHOLE VIRUS VACCINES TRIGGER IMMUNITY? Both live attenuated and inactivated vaccines contain the whole or part of the disease-causing pathogen, but the type of immunity they trigger is slightly different. *Live attenuated vaccines are derived from viruses that have been weakened under laboratory conditions, so that when injected they will infect cells and replicate but cause no or only very mild disease. *They may be unsuitable for people with compromised immune systems (e.g. those with HIV) and pregnant women though, because even a weakened virus may trigger disease in these individuals.
live attenuated vaccines Because these vaccines are simply weakened versions of natural pathogens, the immune system responds as it would to any other cellular invader, mobilizing a range of defenses against it, including killer T cells (which identify and destroy infected cells), helper T cells (which support antibody production) and antibody- producing B cells (which target pathogens lurking elsewhere in the body, e.g. the blood). This immune response continues until the virus is cleared from the body, meaning there is plenty of time for memory cells against the virus to develop. Because of this, live attenuated vaccines can trigger an immune response which is almost as good as being exposed to the wild virus, but without falling ill.
Inactivated virus vaccines Inactivated virus vaccines also contain the disease- causing virus, or parts of it, but their genetic material has been destroyed. For this reason, they are considered safer and more stable than live attenuated vaccines, and they can be given to people with compromised immune systems. Even though their genetic material has been destroyed, inactivated viruses usually contain many proteins which the immune system can react to. But because they cannot infect cells, inactivated vaccines only stimulate antibody-mediated responses, and this response may be weaker and less long- lived. To overcome this problem, inactivated vaccines are often given alongside adjuvants (agents that stimulate the immune system) and booster doses may be required.
Protein subunits vaccines Subunit vaccines use pieces of the pathogen - often fragments of protein - to trigger an immune response. Doing so minimizes the risk of side effects, but it also means the immune response may be weaker. This is why they often require adjuvants, to help boost the immune response. An example of an existing subunit vaccine is the hepatitis B vaccine.
Protein: These vaccines are typically made from coronavirus proteins, which can be synthesized or brewed in labs like beer. Some versions involve coating a carrier—such as nanoparticles—with proteins to better aid delivery and uptake by cells.
Protein subunits vaccines Protein subunit vaccines are considered very safe. There are several types: Protein subunit vaccines contain specific isolated proteins from viral or bacterial pathogens. Polysaccharide vaccines contain chains of sugar molecules (polysaccharides) found in the cell walls of some bacteria. Conjugate subunit vaccines bind a polysaccharide chain to a carrier protein to try and boost the immune response. Only protein subunit vaccines are being developed against the virus that causes COVID-19.
ADVANTAGES AND DISADVANTAGES OF PROTEIN SUBUNIT VACCINES
HOW DO SUBUNIT VACCINES TRIGGER IMMUNITY? Subunit vaccines contain fragments of protein and/or polysaccharide from the pathogen, which have been carefully studied to identify which combinations of these molecules are likely to produce a strong and effective immune response. By restricting the immune system’s access to the pathogen in this way, the risk of side effects is minimized. Such vaccines are also relatively cheap and easy to produce, and more stable than those containing whole viruses or bacteria.
Nucleic acid vaccines Nucleic acid vaccines use genetic material – either RNA or DNA – to provide cells with the instructions to make the antigen. In the case of COVID-19, this is usually the viral spike protein. Once this genetic material gets into human cells, it uses our cells' protein factories to make the antigen that will trigger an immune response. The advantages of such vaccines are that they are easy to make, and cheap. Since the antigen is produced inside our own cells and in large quantities, the immune reaction should be strong. A downside, however, is that so far, no DNA or RNA vaccines have been licensed for human use, which may cause more hurdles with regulatory approval. In addition, RNA vaccines need to be kept at ultra-cold temperatures, -70C or lower, which could prove challenging for countries that don’t have specialized cold storage equipment, particularly low- and middle-income countries.
Nucleic acid vaccines Nucleic acid vaccines use genetic material from a disease-causing virus or bacterium (a pathogen) to stimulate an immune response against it. Depending on the vaccine, the genetic material could be DNA or RNA; in both cases it provides the instructions for making a specific protein from the pathogen, which the immune system will recognize as foreign (an antigen). Once inserted into host cells, this genetic material is read by the cell’s own protein-making machinery and used to manufacture antigens, which then trigger an immune response.
TYPES OF VACCINES Nucleic acid: Relies on injecting snippets of a virus’s genetic material, either DNA or messenger RNA (mRNA), into human cells. It spurs the production of viral proteins that mimic features of the coronavirus, training the immune system to recognize its presence.
ADVANTAGES AND DISADVANTAGES OF NUCLEIC ACID VACCINES
HOW DO NUCLEIC ACID VACCINES TRIGGER IMMUNITY? Once the DNA or RNA is inside the cell and it starts producing antigens, these are then displayed on its surface, where they can be detected by the immune system, triggering a response. This response includes killer T cells, which seek out and destroy infected cells, as well as antibody-producing B cells and helper T cells which support antibody production.
Viral vector vaccines Viral vector vaccines also work by giving cells genetic instructions to produce antigens. But they differ from nucleic acid vaccines in that they use a harmless virus, different from the one the vaccine is targeting, to deliver these instructions into the cell. One type of virus that has often been used as a vector is adenovirus, which causes the common cold. As with nucleic acid vaccines, our own cellular machinery is hijacked to produce the antigen from those instructions, in order to trigger an immune response. Viral vector vaccines can mimic natural viral infection and should therefore trigger a strong immune response. However, since there is a chance that many people may have already been exposed to the viruses being used as vectors, some may be immune to it, making the vaccine less effective.
Viral vector-based Viral vector-based vaccines differ from most conventional vaccines in that they don’t actually contain antigens, but rather use the body’s own cells to produce them. They do this by using a modified virus (the vector) to deliver genetic code for antigen, in the case of COVID-19 spike proteins found on the surface of the virus, into human cells. By infecting cells and instructing them to make large amounts of antigen, which then trigger an immune response, the vaccine mimics what happens during natural infection with certain pathogens - especially viruses. This has the advantage of triggering a strong cellular immune response by T cells as well the production of antibodies by B cells. An example of a viral vector vaccine is the rVSV-ZEBOV vaccine against Ebola.
ADVANTAGES AND DISADVANTAGES OF VIRAL VECTOR-BASED VACCINES
HOW DO VIRAL VECTOR VACCINES TRIGGER IMMUNITY? Once injected into the body, these vaccine viruses begin infecting our cells and inserting their genetic material – including the antigen gene – into the cells’ nuclei. Human cells manufacture the antigen as if it were one of their own proteins and this is presented on their surface alongside many other proteins. When the immune cells detect the foreign antigen, they mount an immune response against it.
Viral vector One type involves introducing a piece of DNA from SARS-CoV-2 into another unrelated germ—for example, an adenovirus, which typically causes the common cold. When this modified adenovirus is injected into humans, the hope is that it will instruct cells to make coronavirus proteins and will trigger an immune response.
According to the World Health Organization (WHO), there are currently more than 100 COVID- 19 vaccine candidates under development, with a number of these in the human trial phase. However, there are only five companies that have given preliminary data about how effective their vaccines could be to fight against coronavirus. These five companies include : Pfizer BioNTech Moderna Inc Oxford University- AstraZeneca Plc, Gamaleya Research Institute of Epidemiology and Microbiology.
COVID-19 vaccines Chinese officials have authorized use of Sinopharm’s COVID-19 vaccine just a day after the company announced it is 79-percent effective. China plans to vaccinate 50 million people by mid-February, despite a lack of published evidence about the safety and efficacy of its available vaccines. Argentina regulators approved the AstraZeneca-Oxford vaccine.
Vaccines record time COVID-19 vaccines have reached consumers in record time. Though the process can typically take 10 to 15 years, the U.S. Food and Drug Administration has granted emergency authorization to vaccines made by Pfizer and Moderna in less than a year. Before now, the fastest-ever vaccine—for mumps—took four years to develop in the 1960s. Yet even after a vaccine is authorized or fully licensed, it faces potential roadblocks when it comes to scaling up production and distribution, which also includes deciding which populations should get it first—and at what cost.
First doses Vaccines Recipients The Centers for Disease Control and Prevention(CDC) have recommended that health-care personnel and long-term care residents receive the first doses. The agency is also proposing that the next in line should be people age 75 or older, and frontline workers.
Vaccines Distributions Several efforts are underway to help produce and distribute the vaccines more quickly, including the U.S. government’s Operation Warp Speed initiative, which has pledged $10 billion and aims to develop and deliver 300 million doses of a safe, effective coronavirus vaccine by January 2021. The World Health Organization is also coordinating global efforts to develop a vaccine, with an eye toward delivering two billion doses by the end of 2021.
VACCINES PRODUCTION PHASES
Clinical trial process More than 60 vaccines are still going through a three-stage clinical trial process that’s required before they are sent to regulatory agencies for approval. Given the urgent need, some vaccine developers have compressed the clinical process for SARS-CoV-2 by running trial phases simultaneously.
VACCINE CLINICAL TRIAL PROCESS Phase one(I) Checks the safety of a vaccine and determines whether it triggers an immune response in a small group of healthy humans.
Phase two(II) Widens the testing pool to include groups of people who may have the disease or be more likely to catch it, to gauge the vaccine’s effectiveness.
Phase three(III) Expands the pool up to the thousands to make sure the vaccine is safe and effective among a wider array of people, given that immune response can vary by age, ethnicity, or by underlying health conditions.
Vaccine rollout and safety Here’s a look at the prospects that have reached phase three and beyond— including a quick primer on how they work and where they stand. As of December 26, the U.S. has administered 1.9 million COVID-19 vaccine doses and distributed 9.5 million doses of the two authorized vaccines made byPfizer-BioNTech and Moderna.
Pfizer/BioNtech vaccine Pfizer and German start-up BioNTech announced their vaccine has the ability to prevent more than 90 per cent of people from getting COVID-19. The drug manufacturers have concluded phase-3 study of their mRNA-based COVID-19 vaccine candidate BNT162b2, and have requested the US Food and Drug Administration (FDA) for Emergency Use Authorization (EUA) of the vaccine. The Pfizer-BioNTech vaccine requires storage at about -70 degrees Celsius, which requires specialized freezers. •Type: mRNA •Doses: 2, 28 Days Apart •Storage: -70 degrees Celsius
Clinical trials status Clinical trials status: On November 18, Pfizer and BioNTech announced the conclusion of their phase three trials. The companies stated that they’ve met their primary goals. The analysis found the candidate to be 95 percent effective in preventing mild cases of COVID-19—and 94 percent effective in adults over 65 years old—with no serious safety concerns. Preliminary results of phase one/two data showed the vaccine produces antibodies and T- cell responses specific to the SARS-CoV-2 protein.
Pfizer • Name: BNT162b2 • Who: One of the world’s largest pharmaceutical companies, based in New York, in collaboration with German biotech company BioNTech. • What: A nucleic-acid vaccine that requires two doses taken 21-28 days apart. • Latest news: On December 27, the European Union began its immunization campaign, administering the Pfizer vaccine to health-care workers and nursing home residents throughout its member states.
Approval status: The FDA granted emergency approval to this vaccine on December 11, a day after an advisory panel decided that the benefits of the candidate outweigh the risks for anyone over the age of 16. The vaccine has also been granted emergency approval in Canada and conditional approval in the European Union. Distribution: The first vaccinations in the U.S. were administered to health-care workers at a medical center in Queens, New York. The CDC has recommended that health-care personnel and long-term care residents receive the first doses, but the ultimate rollout will depend on state decision-making.
Priority For Vaccinations Prioritize vaccinations for the most vulnerable populations, including nursing home residents, health-care workers, older adults, and those with underlying health conditions. - Globally, Pfizer expects to be able to produce up to 1.3 billion doses by the end of 2021. - However, questions have been raised over the vaccine’s storage, which requires ultra-cold freezers set at minus 70 degrees Celsius).
Efficacy and safety Efficacy and safety: The New England Journal of Medicine published the results of Pfizer’s phase three study, showing the vaccine was safe and 95-percent effective in protecting against COVID-19 in people 16 and older. The FDA has also published an analysis saying that the Pfizer vaccine is safe and offers strong protection against COVID-19 within 10 days of the first dose, regardless of the recipient’s race, weight, or age. On December 15, a day after the U.S. launched its immunization campaign, a health-care worker in Alaska was hospitalized for a severe allergic reaction. According to the New York Times, the worker had no history of allergies, and the reaction subsided after she was treated with epinephrine.
Moderna Inc Another company that used the same approach of m-RNA to develop a vaccine against coronavirus has claimed that its vaccine is 95 per cent effective. Moderna Inc's vaccine uses the same approach of injecting part of the virus's genetic code in order to provoke an immune response. Moderna's vaccine candidate mRNA-1273 can be stored at - 20 degrees Celsius for up to six months and can be kept in a standard fridge for up to a month. Type: mRNA Doses: 2, 28 Days Apart
Moderna Therapeutics Name: mRNA-1273 Who: A Massachusetts-based biotech company, in collaboration with the National Institutes of Health. What: A nucleic-acid vaccine that requires two doses, four weeks apart. Latest news: Canada has approved Moderna’s COVID-19 vaccine for use in people 18 years or older. The vaccine’s rollout is expected to begin within 48 hours of the announcement. Approval status: On December 18, the FDA granted emergency approval to Moderna’s COVID-19 vaccine, a day after an advisory panel decided that the benefits of the vaccine outweigh the risks, such as the mild side effects reported in their clinical trial. Distribution: It is the second vaccine to receive emergency authorization in the U.S., joining Pfizer’s candidate, which was approved a week earlier.
Efficacy and safety Efficacy and safety The FDA has also published an analysis of the phase three study of Moderna’s vaccine. It confirms the company’s claims that its candidate is 94.1-percent effective in preventing mild cases of COVID-19 and 100-percent effective at preventing severe cases after taking two doses. Moderna announced on December 22 that it plans to test how well its vaccine works against the new variant of the virus that’s been found in the U.K.
Clinical trials status Moderna announced on December 17 that it is launching clinical trials to evaluate the vaccine’s safety in children and people with cancer; it will also establish a “pregnancy registry” to track the vaccine’s safety in people who are pregnant. The company started the third phase of its clinical trials in July. Preliminary findings from its phase one trials showed that healthy subjects—including elderly patients—produced coronavirus antibodies and a reaction from T cells, another part of the human immune response.
Oxford University/AstraZeneca vaccine British-Swedish pharmaceutical firm AstraZeneca has announced three kinds of data about the efficacy of its vaccine. Interim data suggested 70 per cent protection but the researchers say the figure may be as high as 90 per cent by tweaking the dose. According to AstraZeneca and Oxford University, their vaccine candidate AZD1222 was 90 per cent effective when the first dose was halved and a standard second dose was administered. However, it showed the efficacy of 62 per cent when two full doses were administered to volunteers in 28 days part. Type: Adenovirus-based Doses: 2, 28 Days Apart
AstraZeneca. Name: ChAdOx1 nCoV-19 Who: The U.K. university, in collaboration with the biopharmaceutical company AstraZeneca. What: A viral vector vaccine. Latest news: On December 30, the British government announced that it has authorized use of the AstraZeneca-Oxford vaccine. The U.K. also announced changes to its vaccine delivery plan: With COVID- 19 infections rapidly spreading, the country will now prioritize delivering the first dose of either vaccine to as many at-risk people as possible, based on data provided to and released by health regulators.
Gamaleya Research Institute of Epidemiology and Microbiology Russia became the first country in the world to register a coronavirus vaccine, called Sputnik V in August. The vaccine was registered on 11 August 2020 by the Russian Ministry of Health. The vaccine was approved for distribution in Russia, despite having been tested only in a small number of people in early-stage clinical trials that lasted two months. The institute published phase 1 and 2 results in September but the pivotal phase-3 results are yet to be published. Earlier this month, the institute announced that the vaccine candidate showed 91.4 percent efficacy. Russian Direct Investment Fund (RDIF) has partnered with Indian pharmaceutical company Hetero to produce over 100 million Sputnik V doses in India per year. The production is expected to begin in 2021. Storage: -18 degree Celsius
Efficacy and safety Efficacy and safety On November 11—two days after Pfizer’s announcement of its interim results—Gamaleya reported that an interim analysis of its phase three trial found 92 percent efficacy of the Sputnik vaccine. In September, a study of the institute’s phase one/two trials published in the Lancet showed the vaccine produced antibodies and a reaction from T cells.
Gamaleya National Center of Epidemiology and Microbiology Name: Sputnik V Who: A Russian research institution, in partnership with the state-run Russian Direct Investment Fund. What: A viral vector vaccine that uses two strains of adenovirus and requires a second injection after 21 days to boost the immune response. Latest news: On December 11, the Gamaleya Institute and biopharmaceutical company AstraZeneca announced they will work together to study the possibility of combining Gamaleya’s Sputnik vaccine with the candidate that AstraZeneca has developed with the University of Oxford. Since both candidates use the same adenovirus, researchers will investigate whether combining them will improve efficacy. Clinical trials are expected to begin by the end of the month. Approval status: In August, Russia cleared the Sputnik V vaccine for widespread use and claimed it as the first registered COVID-19 vaccine on the market—before the vaccine’s phase three trials had begun and despite the lack of published evidence at the time. In late December, Belarus and Argentina granted approval and began vaccination campaigns with the Sputnik V vaccine.
Sino pharm • Name: None • Who: China’s state-run pharmaceutical company, in collaboration with the Wuhan Institute of Biological Products. • What: Two inactivated SARS-CoV-2 vaccines. • Latest news: On December 31, China approved one of Sinopharm’s vaccine candidates for use, a day after the company announced results of its phase three study showing the vaccine to be 79-percent effective in preventing COVID-19. • The company did not provide any data backing up its claim. Authorities in the country have set a goal to vaccinate 50 million people by Lunar New Year in mid-February, despite the lack of evidence that their available vaccines are safe and effective. Chinese officials have said the vaccine will be free for Chinese citizens, and that they will prioritize immunizations for high-risk groups such as the elderly and people with underlying conditions. Sino pharm
Approval status: Bahrain and the United Arab Emirates have both approved one of Sinopharm’s vaccines for general use. China has also approved one of the company’s vaccines for general use and another for limited use.
China began to innoculate medical workers and other high-risk groups with the Sinopharm trial vaccines in July, making it the first experimental vaccine available to civilians beyond clinical volunteers Efficacy and safety: In its approval of the Sinopharm vaccine, the UAE said that an interim analysis of the phase three study showed the candidate is 86-percent effective in preventing COVID-19 with no serious safety concerns. UAE officials claimed the vaccine is 100- percent effective in preventing moderate and severe cases of the disease, however no data has been released from the study.
*Preliminary findings from two randomized trials, published in the Journal of the American Medical Association, have shown the vaccine can trigger an antibody response with no serious adverse effects. *The study did not measure T cell-mediated immune responses. *These results are significant, though, as they are the first published data from human clinical trials for a COVID-19 vaccine that uses a whole, inactivated virus.
Sinovac Name: CoronaVac Who: A Chinese biopharmaceutical company, in collaboration with Brazilian research center Butantan. What: An inactivated vaccine. Latest news: expected to grant emergency use authorization to the vaccine by the end of January and roll out its immunization campaign shortly afterward.
Approval status: Approved for limited use in China. Efficacy and safety: On November 17, preliminary results from Sinovac’s early trials reported that the vaccine was safe but produced only a moderate immune response, with lower levels of antibodies compared to those in patients who have recovered from COVID-19. Preliminary results in macaque monkeys, published in Science, revealed that the vaccine produced antibodies that neutralized 10 strains of SARS-CoV-2. Clinical trials status: CoronaVac entered phase three trials in July,
Name: COVAXIN Who: An Indian biotechnology company, in collaboration with the Indian Council of Medical Research and the National Institute of Virology. What: An inactivated vaccine, which requires two doses that are administered 28 days apart. Latest news: On November 16, Bharat Biotech announced it has begun phase three trials involving 26,000 participants at more than 25 centers across India. Approval status: Not approved for use. Efficacy and safety: Results posted online in September but not yet peer reviewed show that the vaccine produced antibodies in monkeys. Bharat Biotech Executive Director Sai Prasad also told Reuters in October that preliminary results from early vaccine trials found more than 90 percent of human participants developed antibodies.
Name: NVX-CoV2373 Who: A biotechnology company based in Gaithersburg, Maryland. What: A protein vaccine that involves a nanoparticle carrier to better aid delivery and uptake by cells. The vaccine is administered in two doses, 21 days apart. Latest news: On December 28, Novavax announced the launch of its phase three study in the U.S. and Mexico, which will evaluate the safety and efficacy of its vaccine in up to 30,000 adults. The announcement comes a month after Novavax said it had completed enrollment in its phase three trial in the U.K., and that it expects to have interim data available in the first quarter of 2021. Approval status: Not approved for use. Efficacy and safety: On September 2, a study of the company’s phase one trial published in the New England Journal of Medicine found that the vaccine was safe and produced coronavirus antibodies at a higher level than is seen among those who have recovered from COVID-19. It also stimulated T cells, another arm of the human immune response.
Name: JNJ-78436735 Who: One of the world’s largest multinational corporations, based in New Jersey, specializing in healthcare and pharmaceutical products. What: An vector vaccine. Latest news: On November 15, Johnson & Johnson launched a second phase three trial to study the safety and efficacy of a two- dose regimen of its vaccine candidate in up to 30,000 volunteers worldwide. The study intends to assess whether a second dose of the vaccine will offer longer protection.
Approval status: Not approved for use. Efficacy and safety: On October 12, Johnson & Johnson announced that it paused phase three trials for an independent safety review due to an unexplained illness in a participant. The company didn’t provide any details, in part to protect the patient’s privacy, but said that illnesses and accidents are expected in large clinical studies.
In July, a study published in Nature showed that the vaccine elicited neutralizing antibodies in monkeys and provided “complete or near-complete” protection with just one dose. Clinical trials status: On September 23, Johnson & Johnson announced the launch of its phase three “ENSEMBLE” trial to evaluate the safety of the vaccine—and how well it works—among up to 60,000 adults from a variety of countries. The trial will include “significant representation” from older populations and those with underlying conditions that make them more susceptible to COVID-19. The company announced on December 17 that the trial is fully enrolled with 45,000 participants; it expects to have interim data available by the end of January.
Name: Bacillus Calmette-Guerin BRACE trial Who: The largest child health research institute in Australia, in collaboration with the University of Melbourne. What: For nearly a hundred years, the Bacillus Calmette- Guerin (BCG) vaccine has been used to prevent tuberculosis by exposing patients to a small dose of live bacteria. Evidence has emerged over the years that this vaccine may boost the immune system and help the body fight off other diseases as well.
Latest news: In October, the U.K. launched a study of the BCG vaccine that is part of the Australian-led trials. The study is seeking to recruit 1,000 frontline health-care workers to test the vaccine’s effectiveness against COVID-19. Clinical trials status: In April, researchers from the Murdoch Children’s Research Institute began a series of randomized controlled trials that will test whether BCG might work on the coronavirus as well. They aim to recruit 10,000 healthcare workers in the study. As of April 12, however, the World Health Organization says there is no evidence that the BCG vaccine protects people against infection with the coronavirus. Approval status: Not approved for use.
Name: Ad5-nCoV Who: A Chinese biopharmaceutical company. What: A viral vector vaccine. Latest news: Indonesia has ordered 20 million doses of CanSino’s vaccine; Mexico is in talks to receive up to 35 million doses. Approval status: Though the company was still technically in phase two of its trial, on June 25, CanSino became the first company to receive limited approval to use its vaccine in people. The Chinese government has approved the vaccine for military use only, for a period of one year.
Efficacy and safety: Preliminary results from phase two trials, published in The Lancet, have shown that the vaccine produces “significant immune responses in the majority of recipients after a single immunisation.” There were no serious adverse reactions documented. Clinical trials status: On December 21, CanSino announced that it has recruited more than 20,000 participants for its phase three trials in Pakistan, Russia, Mexico, and Chile. On August 15, Russian biopharmaceutical company Petrovax announced it had launched the first phase three clinical trial of Ad5-nCoV.
Vector Institute Name: EpiVacCorona Who: A Russian biotechnology institute. What: A protein vaccine, namely it uses small fragments of viral antigens called peptides to produce an immune response. Latest news: In November, Russia launched mass trials of its EpiVacCorona vaccine; the trials will innoculate 150 people over the age of 60 and 3,000 volunteers over the age of 18.
The CDC has also released the first data on the COVID-19 vaccines from its Vaccine Adverse Event Reporting System, which collects reports of allergic reactions and other adverse events from health- care providers, vaccine manufacturers, and the public.
It will do so by delaying administration of the second dose of the AstraZeneca- Oxford drug; originally intended to be administered a few weeks after the first dose, patients will instead receive the second dose within 12 weeks. A similar rule was issued for the Pfizer-BioNTech vaccine—its two doses were previously split over three weeks—but regulators didn’t provide similar data to back the new regimen. Overall, the U.K. still recommends that recipients receive two doses of either vaccine for maximum benefit. Rollout of the AstraZeneca-Oxford vaccine will begin on January 4. Argentina announced a similar approval the same day as the U.K.
Prof.Amal Sayed IPC DIRECTOR CAIRO UNIVERSITY HOSPITAL

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COVID-19 VACCINES

  • 1.
  • 3.
    Vaccine prospects The COVID-19candidates, like all vaccines, essentially aim to instruct the immune system to mount a defense, which is sometimes stronger than what would be provided through natural infection and comes with fewer health consequences.
  • 4.
    COVID-19 vaccine typesin development Candidates in Clinical Phases I-III
  • 5.
    Vaccines Development To doso, traditional vaccines use the whole coronavirus, but in a killed or weakened state. Others use only part of the virus— whether a protein or a fragment. Some transfer the instructions for coronavirus proteins into an unrelated virus that is unlikely or even incapable of causing disease. Finally, cutting-edge vaccines under development rely on deploying pieces of the coronavirus’s genetic material, enabling our cells to temporarily make coronavirus proteins needed to stimulate our immune systems.
  • 6.
    COVID-19 vaccine typesin development
  • 7.
    There are morevaccine candidates simultaneously in the pipeline for COVID-19 than ever before for an infectious disease. All of them are trying to achieve the same thing – immunity to the virus, and some might also be able to stop transmission. They do so by stimulating an immune response to an antigen, a molecule found on the virus. In the case of COVID-19, the antigen is typically the characteristic spike protein found on the surface of the virus, which it normally uses to help it invade human cells.
  • 8.
    THE FOUR MAINTYPES OF COVID-19 VACCINE There are four categories of vaccines in clinical trials: WHOLE VIRUS PROTEIN SUBUNIT VIRAL VECTOR NUCLEIC ACID (RNA AND DNA) Some of them try to smuggle the antigen into the body, others use the body’s own cells to make the viral antigen.
  • 9.
    Whole viruses vaccines Many conventionalvaccines use whole viruses to trigger an immune response. There are two main approaches. Live attenuated vaccines use a weakened form of the virus that can still replicate without causing illness. Inactivated vaccines use viruses whose genetic material has been destroyed so they cannot replicate, but can still trigger an immune response.
  • 11.
    Knocked-out whole virus Uses anon-infectious form of the coronavirus that can no longer cause full-blown disease but can still provoke an immune response. The virus can either be fully inactivated or weakened. These modes are considered the most classic ways to make vaccines.
  • 12.
    Both types usewell-established technology and pathways for regulatory approval, but live attenuated ones may risk causing disease in people with weak immune systems and often require careful cold storage, making their use more challenging in low-resource countries. Inactivated virus vaccines can be given to people with compromised immune systems but might also need cold storage.
  • 13.
    Whole virus vaccines Bothare tried and tested vaccination strategies, which form the basis of many existing vaccines – including those for yellow fever and measles (live attenuated vaccines), or seasonal influenza and hepatitis A (inactivated vaccines). Bacterial attenuated vaccines also exist, such as the BCG vaccine for tuberculosis Live attenuated vaccines use a weakened form of the virus, which can still grow and replicate, but does not cause illness. Inactivated vaccines contain viruses whose genetic material has been destroyed by heat, chemicals or radiation so they cannot infect cells and replicate, but can still trigger an immune response.
  • 14.
    ADVANTAGES AND DISADVANTAGESOF LIVE ATTENUATED VACCINES
  • 15.
    ADVANTAGES AND DISADVANTAGESOF INACTIVATED VIRUS VACCINES
  • 16.
    HOW DO WHOLEVIRUS VACCINES TRIGGER IMMUNITY? Both live attenuated and inactivated vaccines contain the whole or part of the disease-causing pathogen, but the type of immunity they trigger is slightly different. *Live attenuated vaccines are derived from viruses that have been weakened under laboratory conditions, so that when injected they will infect cells and replicate but cause no or only very mild disease. *They may be unsuitable for people with compromised immune systems (e.g. those with HIV) and pregnant women though, because even a weakened virus may trigger disease in these individuals.
  • 17.
    live attenuated vaccines Becausethese vaccines are simply weakened versions of natural pathogens, the immune system responds as it would to any other cellular invader, mobilizing a range of defenses against it, including killer T cells (which identify and destroy infected cells), helper T cells (which support antibody production) and antibody- producing B cells (which target pathogens lurking elsewhere in the body, e.g. the blood). This immune response continues until the virus is cleared from the body, meaning there is plenty of time for memory cells against the virus to develop. Because of this, live attenuated vaccines can trigger an immune response which is almost as good as being exposed to the wild virus, but without falling ill.
  • 18.
    Inactivated virus vaccines Inactivatedvirus vaccines also contain the disease- causing virus, or parts of it, but their genetic material has been destroyed. For this reason, they are considered safer and more stable than live attenuated vaccines, and they can be given to people with compromised immune systems. Even though their genetic material has been destroyed, inactivated viruses usually contain many proteins which the immune system can react to. But because they cannot infect cells, inactivated vaccines only stimulate antibody-mediated responses, and this response may be weaker and less long- lived. To overcome this problem, inactivated vaccines are often given alongside adjuvants (agents that stimulate the immune system) and booster doses may be required.
  • 19.
    Protein subunits vaccines Subunitvaccines use pieces of the pathogen - often fragments of protein - to trigger an immune response. Doing so minimizes the risk of side effects, but it also means the immune response may be weaker. This is why they often require adjuvants, to help boost the immune response. An example of an existing subunit vaccine is the hepatitis B vaccine.
  • 20.
    Protein: These vaccinesare typically made from coronavirus proteins, which can be synthesized or brewed in labs like beer. Some versions involve coating a carrier—such as nanoparticles—with proteins to better aid delivery and uptake by cells.
  • 21.
    Protein subunits vaccines Proteinsubunit vaccines are considered very safe. There are several types: Protein subunit vaccines contain specific isolated proteins from viral or bacterial pathogens. Polysaccharide vaccines contain chains of sugar molecules (polysaccharides) found in the cell walls of some bacteria. Conjugate subunit vaccines bind a polysaccharide chain to a carrier protein to try and boost the immune response. Only protein subunit vaccines are being developed against the virus that causes COVID-19.
  • 22.
    ADVANTAGES AND DISADVANTAGESOF PROTEIN SUBUNIT VACCINES
  • 23.
    HOW DO SUBUNITVACCINES TRIGGER IMMUNITY? Subunit vaccines contain fragments of protein and/or polysaccharide from the pathogen, which have been carefully studied to identify which combinations of these molecules are likely to produce a strong and effective immune response. By restricting the immune system’s access to the pathogen in this way, the risk of side effects is minimized. Such vaccines are also relatively cheap and easy to produce, and more stable than those containing whole viruses or bacteria.
  • 25.
    Nucleic acid vaccines Nucleicacid vaccines use genetic material – either RNA or DNA – to provide cells with the instructions to make the antigen. In the case of COVID-19, this is usually the viral spike protein. Once this genetic material gets into human cells, it uses our cells' protein factories to make the antigen that will trigger an immune response. The advantages of such vaccines are that they are easy to make, and cheap. Since the antigen is produced inside our own cells and in large quantities, the immune reaction should be strong. A downside, however, is that so far, no DNA or RNA vaccines have been licensed for human use, which may cause more hurdles with regulatory approval. In addition, RNA vaccines need to be kept at ultra-cold temperatures, -70C or lower, which could prove challenging for countries that don’t have specialized cold storage equipment, particularly low- and middle-income countries.
  • 26.
    Nucleic acid vaccines Nucleicacid vaccines use genetic material from a disease-causing virus or bacterium (a pathogen) to stimulate an immune response against it. Depending on the vaccine, the genetic material could be DNA or RNA; in both cases it provides the instructions for making a specific protein from the pathogen, which the immune system will recognize as foreign (an antigen). Once inserted into host cells, this genetic material is read by the cell’s own protein-making machinery and used to manufacture antigens, which then trigger an immune response.
  • 27.
    TYPES OF VACCINES Nucleicacid: Relies on injecting snippets of a virus’s genetic material, either DNA or messenger RNA (mRNA), into human cells. It spurs the production of viral proteins that mimic features of the coronavirus, training the immune system to recognize its presence.
  • 28.
    ADVANTAGES AND DISADVANTAGESOF NUCLEIC ACID VACCINES
  • 29.
    HOW DO NUCLEICACID VACCINES TRIGGER IMMUNITY? Once the DNA or RNA is inside the cell and it starts producing antigens, these are then displayed on its surface, where they can be detected by the immune system, triggering a response. This response includes killer T cells, which seek out and destroy infected cells, as well as antibody-producing B cells and helper T cells which support antibody production.
  • 32.
    Viral vector vaccines Viralvector vaccines also work by giving cells genetic instructions to produce antigens. But they differ from nucleic acid vaccines in that they use a harmless virus, different from the one the vaccine is targeting, to deliver these instructions into the cell. One type of virus that has often been used as a vector is adenovirus, which causes the common cold. As with nucleic acid vaccines, our own cellular machinery is hijacked to produce the antigen from those instructions, in order to trigger an immune response. Viral vector vaccines can mimic natural viral infection and should therefore trigger a strong immune response. However, since there is a chance that many people may have already been exposed to the viruses being used as vectors, some may be immune to it, making the vaccine less effective.
  • 33.
    Viral vector-based Viral vector-basedvaccines differ from most conventional vaccines in that they don’t actually contain antigens, but rather use the body’s own cells to produce them. They do this by using a modified virus (the vector) to deliver genetic code for antigen, in the case of COVID-19 spike proteins found on the surface of the virus, into human cells. By infecting cells and instructing them to make large amounts of antigen, which then trigger an immune response, the vaccine mimics what happens during natural infection with certain pathogens - especially viruses. This has the advantage of triggering a strong cellular immune response by T cells as well the production of antibodies by B cells. An example of a viral vector vaccine is the rVSV-ZEBOV vaccine against Ebola.
  • 34.
    ADVANTAGES AND DISADVANTAGESOF VIRAL VECTOR-BASED VACCINES
  • 35.
    HOW DO VIRALVECTOR VACCINES TRIGGER IMMUNITY? Once injected into the body, these vaccine viruses begin infecting our cells and inserting their genetic material – including the antigen gene – into the cells’ nuclei. Human cells manufacture the antigen as if it were one of their own proteins and this is presented on their surface alongside many other proteins. When the immune cells detect the foreign antigen, they mount an immune response against it.
  • 36.
    Viral vector One typeinvolves introducing a piece of DNA from SARS-CoV-2 into another unrelated germ—for example, an adenovirus, which typically causes the common cold. When this modified adenovirus is injected into humans, the hope is that it will instruct cells to make coronavirus proteins and will trigger an immune response.
  • 37.
    According to theWorld Health Organization (WHO), there are currently more than 100 COVID- 19 vaccine candidates under development, with a number of these in the human trial phase. However, there are only five companies that have given preliminary data about how effective their vaccines could be to fight against coronavirus. These five companies include : Pfizer BioNTech Moderna Inc Oxford University- AstraZeneca Plc, Gamaleya Research Institute of Epidemiology and Microbiology.
  • 38.
    COVID-19 vaccines Chinese officials haveauthorized use of Sinopharm’s COVID-19 vaccine just a day after the company announced it is 79-percent effective. China plans to vaccinate 50 million people by mid-February, despite a lack of published evidence about the safety and efficacy of its available vaccines. Argentina regulators approved the AstraZeneca-Oxford vaccine.
  • 39.
    Vaccines record time COVID-19vaccines have reached consumers in record time. Though the process can typically take 10 to 15 years, the U.S. Food and Drug Administration has granted emergency authorization to vaccines made by Pfizer and Moderna in less than a year. Before now, the fastest-ever vaccine—for mumps—took four years to develop in the 1960s. Yet even after a vaccine is authorized or fully licensed, it faces potential roadblocks when it comes to scaling up production and distribution, which also includes deciding which populations should get it first—and at what cost.
  • 40.
    First doses Vaccines Recipients TheCenters for Disease Control and Prevention(CDC) have recommended that health-care personnel and long-term care residents receive the first doses. The agency is also proposing that the next in line should be people age 75 or older, and frontline workers.
  • 41.
    Vaccines Distributions Several effortsare underway to help produce and distribute the vaccines more quickly, including the U.S. government’s Operation Warp Speed initiative, which has pledged $10 billion and aims to develop and deliver 300 million doses of a safe, effective coronavirus vaccine by January 2021. The World Health Organization is also coordinating global efforts to develop a vaccine, with an eye toward delivering two billion doses by the end of 2021.
  • 42.
  • 44.
    Clinical trial process Morethan 60 vaccines are still going through a three-stage clinical trial process that’s required before they are sent to regulatory agencies for approval. Given the urgent need, some vaccine developers have compressed the clinical process for SARS-CoV-2 by running trial phases simultaneously.
  • 45.
    VACCINE CLINICAL TRIALPROCESS Phase one(I) Checks the safety of a vaccine and determines whether it triggers an immune response in a small group of healthy humans.
  • 46.
    Phase two(II) Widens thetesting pool to include groups of people who may have the disease or be more likely to catch it, to gauge the vaccine’s effectiveness.
  • 47.
    Phase three(III) Expands thepool up to the thousands to make sure the vaccine is safe and effective among a wider array of people, given that immune response can vary by age, ethnicity, or by underlying health conditions.
  • 48.
    Vaccine rollout andsafety Here’s a look at the prospects that have reached phase three and beyond— including a quick primer on how they work and where they stand. As of December 26, the U.S. has administered 1.9 million COVID-19 vaccine doses and distributed 9.5 million doses of the two authorized vaccines made byPfizer-BioNTech and Moderna.
  • 50.
    Pfizer/BioNtech vaccine Pfizer andGerman start-up BioNTech announced their vaccine has the ability to prevent more than 90 per cent of people from getting COVID-19. The drug manufacturers have concluded phase-3 study of their mRNA-based COVID-19 vaccine candidate BNT162b2, and have requested the US Food and Drug Administration (FDA) for Emergency Use Authorization (EUA) of the vaccine. The Pfizer-BioNTech vaccine requires storage at about -70 degrees Celsius, which requires specialized freezers. •Type: mRNA •Doses: 2, 28 Days Apart •Storage: -70 degrees Celsius
  • 51.
    Clinical trials status Clinicaltrials status: On November 18, Pfizer and BioNTech announced the conclusion of their phase three trials. The companies stated that they’ve met their primary goals. The analysis found the candidate to be 95 percent effective in preventing mild cases of COVID-19—and 94 percent effective in adults over 65 years old—with no serious safety concerns. Preliminary results of phase one/two data showed the vaccine produces antibodies and T- cell responses specific to the SARS-CoV-2 protein.
  • 52.
    Pfizer • Name: BNT162b2 •Who: One of the world’s largest pharmaceutical companies, based in New York, in collaboration with German biotech company BioNTech. • What: A nucleic-acid vaccine that requires two doses taken 21-28 days apart. • Latest news: On December 27, the European Union began its immunization campaign, administering the Pfizer vaccine to health-care workers and nursing home residents throughout its member states.
  • 53.
    Approval status: TheFDA granted emergency approval to this vaccine on December 11, a day after an advisory panel decided that the benefits of the candidate outweigh the risks for anyone over the age of 16. The vaccine has also been granted emergency approval in Canada and conditional approval in the European Union. Distribution: The first vaccinations in the U.S. were administered to health-care workers at a medical center in Queens, New York. The CDC has recommended that health-care personnel and long-term care residents receive the first doses, but the ultimate rollout will depend on state decision-making.
  • 54.
    Priority For Vaccinations Prioritize vaccinationsfor the most vulnerable populations, including nursing home residents, health-care workers, older adults, and those with underlying health conditions. - Globally, Pfizer expects to be able to produce up to 1.3 billion doses by the end of 2021. - However, questions have been raised over the vaccine’s storage, which requires ultra-cold freezers set at minus 70 degrees Celsius).
  • 55.
    Efficacy and safety Efficacyand safety: The New England Journal of Medicine published the results of Pfizer’s phase three study, showing the vaccine was safe and 95-percent effective in protecting against COVID-19 in people 16 and older. The FDA has also published an analysis saying that the Pfizer vaccine is safe and offers strong protection against COVID-19 within 10 days of the first dose, regardless of the recipient’s race, weight, or age. On December 15, a day after the U.S. launched its immunization campaign, a health-care worker in Alaska was hospitalized for a severe allergic reaction. According to the New York Times, the worker had no history of allergies, and the reaction subsided after she was treated with epinephrine.
  • 57.
    Moderna Inc Another companythat used the same approach of m-RNA to develop a vaccine against coronavirus has claimed that its vaccine is 95 per cent effective. Moderna Inc's vaccine uses the same approach of injecting part of the virus's genetic code in order to provoke an immune response. Moderna's vaccine candidate mRNA-1273 can be stored at - 20 degrees Celsius for up to six months and can be kept in a standard fridge for up to a month. Type: mRNA Doses: 2, 28 Days Apart
  • 58.
    Moderna Therapeutics Name: mRNA-1273 Who:A Massachusetts-based biotech company, in collaboration with the National Institutes of Health. What: A nucleic-acid vaccine that requires two doses, four weeks apart. Latest news: Canada has approved Moderna’s COVID-19 vaccine for use in people 18 years or older. The vaccine’s rollout is expected to begin within 48 hours of the announcement. Approval status: On December 18, the FDA granted emergency approval to Moderna’s COVID-19 vaccine, a day after an advisory panel decided that the benefits of the vaccine outweigh the risks, such as the mild side effects reported in their clinical trial. Distribution: It is the second vaccine to receive emergency authorization in the U.S., joining Pfizer’s candidate, which was approved a week earlier.
  • 59.
    Efficacy and safety Efficacyand safety The FDA has also published an analysis of the phase three study of Moderna’s vaccine. It confirms the company’s claims that its candidate is 94.1-percent effective in preventing mild cases of COVID-19 and 100-percent effective at preventing severe cases after taking two doses. Moderna announced on December 22 that it plans to test how well its vaccine works against the new variant of the virus that’s been found in the U.K.
  • 60.
    Clinical trials status Modernaannounced on December 17 that it is launching clinical trials to evaluate the vaccine’s safety in children and people with cancer; it will also establish a “pregnancy registry” to track the vaccine’s safety in people who are pregnant. The company started the third phase of its clinical trials in July. Preliminary findings from its phase one trials showed that healthy subjects—including elderly patients—produced coronavirus antibodies and a reaction from T cells, another part of the human immune response.
  • 62.
    Oxford University/AstraZeneca vaccine British-Swedishpharmaceutical firm AstraZeneca has announced three kinds of data about the efficacy of its vaccine. Interim data suggested 70 per cent protection but the researchers say the figure may be as high as 90 per cent by tweaking the dose. According to AstraZeneca and Oxford University, their vaccine candidate AZD1222 was 90 per cent effective when the first dose was halved and a standard second dose was administered. However, it showed the efficacy of 62 per cent when two full doses were administered to volunteers in 28 days part. Type: Adenovirus-based Doses: 2, 28 Days Apart
  • 63.
    AstraZeneca. Name: ChAdOx1 nCoV-19 Who:The U.K. university, in collaboration with the biopharmaceutical company AstraZeneca. What: A viral vector vaccine. Latest news: On December 30, the British government announced that it has authorized use of the AstraZeneca-Oxford vaccine. The U.K. also announced changes to its vaccine delivery plan: With COVID- 19 infections rapidly spreading, the country will now prioritize delivering the first dose of either vaccine to as many at-risk people as possible, based on data provided to and released by health regulators.
  • 66.
    Gamaleya Research Instituteof Epidemiology and Microbiology Russia became the first country in the world to register a coronavirus vaccine, called Sputnik V in August. The vaccine was registered on 11 August 2020 by the Russian Ministry of Health. The vaccine was approved for distribution in Russia, despite having been tested only in a small number of people in early-stage clinical trials that lasted two months. The institute published phase 1 and 2 results in September but the pivotal phase-3 results are yet to be published. Earlier this month, the institute announced that the vaccine candidate showed 91.4 percent efficacy. Russian Direct Investment Fund (RDIF) has partnered with Indian pharmaceutical company Hetero to produce over 100 million Sputnik V doses in India per year. The production is expected to begin in 2021. Storage: -18 degree Celsius
  • 67.
    Efficacy and safety Efficacyand safety On November 11—two days after Pfizer’s announcement of its interim results—Gamaleya reported that an interim analysis of its phase three trial found 92 percent efficacy of the Sputnik vaccine. In September, a study of the institute’s phase one/two trials published in the Lancet showed the vaccine produced antibodies and a reaction from T cells.
  • 68.
    Gamaleya National Centerof Epidemiology and Microbiology Name: Sputnik V Who: A Russian research institution, in partnership with the state-run Russian Direct Investment Fund. What: A viral vector vaccine that uses two strains of adenovirus and requires a second injection after 21 days to boost the immune response. Latest news: On December 11, the Gamaleya Institute and biopharmaceutical company AstraZeneca announced they will work together to study the possibility of combining Gamaleya’s Sputnik vaccine with the candidate that AstraZeneca has developed with the University of Oxford. Since both candidates use the same adenovirus, researchers will investigate whether combining them will improve efficacy. Clinical trials are expected to begin by the end of the month. Approval status: In August, Russia cleared the Sputnik V vaccine for widespread use and claimed it as the first registered COVID-19 vaccine on the market—before the vaccine’s phase three trials had begun and despite the lack of published evidence at the time. In late December, Belarus and Argentina granted approval and began vaccination campaigns with the Sputnik V vaccine.
  • 70.
    Sino pharm • Name:None • Who: China’s state-run pharmaceutical company, in collaboration with the Wuhan Institute of Biological Products. • What: Two inactivated SARS-CoV-2 vaccines. • Latest news: On December 31, China approved one of Sinopharm’s vaccine candidates for use, a day after the company announced results of its phase three study showing the vaccine to be 79-percent effective in preventing COVID-19. • The company did not provide any data backing up its claim. Authorities in the country have set a goal to vaccinate 50 million people by Lunar New Year in mid-February, despite the lack of evidence that their available vaccines are safe and effective. Chinese officials have said the vaccine will be free for Chinese citizens, and that they will prioritize immunizations for high-risk groups such as the elderly and people with underlying conditions. Sino pharm
  • 71.
    Approval status: Bahrainand the United Arab Emirates have both approved one of Sinopharm’s vaccines for general use. China has also approved one of the company’s vaccines for general use and another for limited use.
  • 72.
    China began toinnoculate medical workers and other high-risk groups with the Sinopharm trial vaccines in July, making it the first experimental vaccine available to civilians beyond clinical volunteers Efficacy and safety: In its approval of the Sinopharm vaccine, the UAE said that an interim analysis of the phase three study showed the candidate is 86-percent effective in preventing COVID-19 with no serious safety concerns. UAE officials claimed the vaccine is 100- percent effective in preventing moderate and severe cases of the disease, however no data has been released from the study.
  • 73.
    *Preliminary findings fromtwo randomized trials, published in the Journal of the American Medical Association, have shown the vaccine can trigger an antibody response with no serious adverse effects. *The study did not measure T cell-mediated immune responses. *These results are significant, though, as they are the first published data from human clinical trials for a COVID-19 vaccine that uses a whole, inactivated virus.
  • 75.
    Sinovac Name: CoronaVac Who: AChinese biopharmaceutical company, in collaboration with Brazilian research center Butantan. What: An inactivated vaccine. Latest news: expected to grant emergency use authorization to the vaccine by the end of January and roll out its immunization campaign shortly afterward.
  • 76.
    Approval status: Approvedfor limited use in China. Efficacy and safety: On November 17, preliminary results from Sinovac’s early trials reported that the vaccine was safe but produced only a moderate immune response, with lower levels of antibodies compared to those in patients who have recovered from COVID-19. Preliminary results in macaque monkeys, published in Science, revealed that the vaccine produced antibodies that neutralized 10 strains of SARS-CoV-2. Clinical trials status: CoronaVac entered phase three trials in July,
  • 78.
    Name: COVAXIN Who: AnIndian biotechnology company, in collaboration with the Indian Council of Medical Research and the National Institute of Virology. What: An inactivated vaccine, which requires two doses that are administered 28 days apart. Latest news: On November 16, Bharat Biotech announced it has begun phase three trials involving 26,000 participants at more than 25 centers across India. Approval status: Not approved for use. Efficacy and safety: Results posted online in September but not yet peer reviewed show that the vaccine produced antibodies in monkeys. Bharat Biotech Executive Director Sai Prasad also told Reuters in October that preliminary results from early vaccine trials found more than 90 percent of human participants developed antibodies.
  • 80.
    Name: NVX-CoV2373 Who: Abiotechnology company based in Gaithersburg, Maryland. What: A protein vaccine that involves a nanoparticle carrier to better aid delivery and uptake by cells. The vaccine is administered in two doses, 21 days apart. Latest news: On December 28, Novavax announced the launch of its phase three study in the U.S. and Mexico, which will evaluate the safety and efficacy of its vaccine in up to 30,000 adults. The announcement comes a month after Novavax said it had completed enrollment in its phase three trial in the U.K., and that it expects to have interim data available in the first quarter of 2021. Approval status: Not approved for use. Efficacy and safety: On September 2, a study of the company’s phase one trial published in the New England Journal of Medicine found that the vaccine was safe and produced coronavirus antibodies at a higher level than is seen among those who have recovered from COVID-19. It also stimulated T cells, another arm of the human immune response.
  • 82.
    Name: JNJ-78436735 Who: Oneof the world’s largest multinational corporations, based in New Jersey, specializing in healthcare and pharmaceutical products. What: An vector vaccine. Latest news: On November 15, Johnson & Johnson launched a second phase three trial to study the safety and efficacy of a two- dose regimen of its vaccine candidate in up to 30,000 volunteers worldwide. The study intends to assess whether a second dose of the vaccine will offer longer protection.
  • 83.
    Approval status: Not approvedfor use. Efficacy and safety: On October 12, Johnson & Johnson announced that it paused phase three trials for an independent safety review due to an unexplained illness in a participant. The company didn’t provide any details, in part to protect the patient’s privacy, but said that illnesses and accidents are expected in large clinical studies.
  • 84.
    In July, astudy published in Nature showed that the vaccine elicited neutralizing antibodies in monkeys and provided “complete or near-complete” protection with just one dose. Clinical trials status: On September 23, Johnson & Johnson announced the launch of its phase three “ENSEMBLE” trial to evaluate the safety of the vaccine—and how well it works—among up to 60,000 adults from a variety of countries. The trial will include “significant representation” from older populations and those with underlying conditions that make them more susceptible to COVID-19. The company announced on December 17 that the trial is fully enrolled with 45,000 participants; it expects to have interim data available by the end of January.
  • 86.
    Name: Bacillus Calmette-GuerinBRACE trial Who: The largest child health research institute in Australia, in collaboration with the University of Melbourne. What: For nearly a hundred years, the Bacillus Calmette- Guerin (BCG) vaccine has been used to prevent tuberculosis by exposing patients to a small dose of live bacteria. Evidence has emerged over the years that this vaccine may boost the immune system and help the body fight off other diseases as well.
  • 87.
    Latest news: InOctober, the U.K. launched a study of the BCG vaccine that is part of the Australian-led trials. The study is seeking to recruit 1,000 frontline health-care workers to test the vaccine’s effectiveness against COVID-19. Clinical trials status: In April, researchers from the Murdoch Children’s Research Institute began a series of randomized controlled trials that will test whether BCG might work on the coronavirus as well. They aim to recruit 10,000 healthcare workers in the study. As of April 12, however, the World Health Organization says there is no evidence that the BCG vaccine protects people against infection with the coronavirus. Approval status: Not approved for use.
  • 89.
    Name: Ad5-nCoV Who: AChinese biopharmaceutical company. What: A viral vector vaccine. Latest news: Indonesia has ordered 20 million doses of CanSino’s vaccine; Mexico is in talks to receive up to 35 million doses. Approval status: Though the company was still technically in phase two of its trial, on June 25, CanSino became the first company to receive limited approval to use its vaccine in people. The Chinese government has approved the vaccine for military use only, for a period of one year.
  • 90.
    Efficacy and safety:Preliminary results from phase two trials, published in The Lancet, have shown that the vaccine produces “significant immune responses in the majority of recipients after a single immunisation.” There were no serious adverse reactions documented. Clinical trials status: On December 21, CanSino announced that it has recruited more than 20,000 participants for its phase three trials in Pakistan, Russia, Mexico, and Chile. On August 15, Russian biopharmaceutical company Petrovax announced it had launched the first phase three clinical trial of Ad5-nCoV.
  • 96.
    Vector Institute Name: EpiVacCoronaWho: A Russian biotechnology institute. What: A protein vaccine, namely it uses small fragments of viral antigens called peptides to produce an immune response. Latest news: In November, Russia launched mass trials of its EpiVacCorona vaccine; the trials will innoculate 150 people over the age of 60 and 3,000 volunteers over the age of 18.
  • 97.
    The CDC hasalso released the first data on the COVID-19 vaccines from its Vaccine Adverse Event Reporting System, which collects reports of allergic reactions and other adverse events from health- care providers, vaccine manufacturers, and the public.
  • 98.
    It will doso by delaying administration of the second dose of the AstraZeneca- Oxford drug; originally intended to be administered a few weeks after the first dose, patients will instead receive the second dose within 12 weeks. A similar rule was issued for the Pfizer-BioNTech vaccine—its two doses were previously split over three weeks—but regulators didn’t provide similar data to back the new regimen. Overall, the U.K. still recommends that recipients receive two doses of either vaccine for maximum benefit. Rollout of the AstraZeneca-Oxford vaccine will begin on January 4. Argentina announced a similar approval the same day as the U.K.
  • 101.
    Prof.Amal Sayed IPC DIRECTORCAIRO UNIVERSITY HOSPITAL