How Do COVID-19 Vaccines Work?
Generally, when a virus or pathogen enters our bodies, they attack the cells and multiplies. The body's immune system prevents this infection from progressing with the help of different types of white blood cells. Macrophages (one type of white blood cell) engulf and digest the virus and damaged cells. These macrophages leave behind some parts of the virus called antigens. B-lymphocytes, defensive white blood cells, produce antibodies that try to destroy the antigens left behind by macrophages. T-lymphocytes, another type of white blood cell, attack the infected cells in the body.
All these processes take a few days to weeks, and the immune system eventually fights the infection off (ideally). After the initial infection, the immune system remembers how to fight off that particular pathogen if it invades the body again. Some T-lymphocytes or memory cells remain in the body, and they attack immediately if the body reencounters the same virus.
COVID-19 vaccines are designed to provide the same immunity without getting infected with the virus. Different types of vaccines work in different ways, but in the end, all the vaccines lead to the formation of B and T-lymphocytes. These cells remember how to fight that virus in case the person gets infected in the future. The case division between vaccinated individuals and those who took the placebo indicates a vaccine efficacy rate above 90 % seven days after getting fully vaccinated.
What Are the Types of COVID-19 Vaccines?
The four main types of COVID-19 vaccines are:
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Whole Virus Vaccines - Many vaccines use the entire virus, either in the live-attenuated form or inactivated form, to trigger an immune response. Live-attenuated vaccines use a weakened form of the virus, which cannot cause illness but can replicate. While viruses with destroyed genetic material can no longer multiply, they can activate the immune system and are used in inactivated vaccines.
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Protein Subunit Vaccines - They contain viral protein, which triggers the immune system to make T-lymphocytes and antibodies. Only using the protein minimizes the risk of side effects, but the immune response might also be weak, which is why they often require adjuvants to boost the immune response.
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Nucleic Acid Vaccines - These vaccines either use viral spike protein or viral RNA or DNA. When this genetic material enters the human cells, it uses our cells to make the viral antigen, which triggers an immune response. These vaccines are easier to make and are cheaper.
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Viral Vector Vaccines - These vaccines also give our cells instructions to produce viral antigens. But instead of using the nucleic acid from the virus, it uses a harmless virus (not the one against which the virus is targeted). Adenovirus (the virus that causes the common cold) is often used as a vector. The side effect of this vaccine is that many might already be exposed to various adenoviruses, and when it is used as a vector, the immunity destroys it, which results in an inadequate immune response.
COVID-19 Vaccine Timeline:
A COVID‑19 vaccine is intended to provide immunity or protection against the new Coronavirus (SARS-CoV-2). Before the current pandemic, as scientists were working on developing vaccines against SARS - Severe acute respiratory syndrome and MERS - Middle East respiratory syndrome, which are diseases caused by other strains of Coronaviruses, they already had an idea about the structure and function of this virus. This accelerated the work of developing COVID‑19 vaccines. The work began on these vaccines in January, soon after the virus's genome was deciphered.
In November 2020, Moderna, BioNTech and Pfizer Inc, Gamaleya Institute, and the University of Oxford announced positive vaccine trial results. By December 2020, almost 40 vaccines were in Phase I to II of their clinical trials and 17 in Phase II to III. And by 19th December 2020, 16 countries had approved the BioNTech and Pfizer Inc vaccine (Tozinameran) for emergency use. The United Arab Emirates (UAE) and Bahrain have authorized the vaccine manufactured by Sinopharm (China National Pharmaceutical Group Corp). By 16th December in the UK, around 1,38,000 people had received Tozinameran. The FDA (the United States Food and Drug Administration) granted an Emergency Use Authorization (EUA) for Tozinameran on 11th December 2020 and also granted a EUA for the Moderna vaccine (mRNA-1273) a week later on 18th December 2020. The Centers for disease control and prevention published ACIP interim recommendations for using the Pfizer-BioNTech vaccine on 13th December 2020, and two days later, the same was published for the Moderna vaccine.
The emergency use authorization was issued by the FDA for Johnson & Johnson COVID-19 vaccine on February 27, 2021, and the ACIP interim recommendation for its use was published on March 2, 2021. On April 13, 2021, the FDA issued a pause for the use of the Johnson & Johnson vaccine in view of the thrombolytic side effects, which was then reviewed, and the use of the vaccination resumed after ten days. The EUA for the Pfizer-BioNTech vaccine in adolescents between 12 to 15 years was issued on May 10, 2021, and later, after four days, its use was approved by the AICP interim recommendations.
Pfizer and Moderna vaccines were given the EUA for the administration of booster doses in immunocompromised individuals on August 12, 2021. Pfizer-BioNTech became the first approved vaccine by the FDA on August 23, 2021, in people above the age of 16 years. On September 22, 2021, FDA authorized the use of Pfizer-BioNTech vaccine booster doses in individuals above the age of 65 years, individuals between the ages of 18 and 64, and have an increased risk of developing severe COVID-19 or have increased occupational exposure to COVID-19.
On October 20, 2021, FDA authorized the administration of booster doses of Pfizer-BioNTech, Moderna, and Johnson & Johnson vaccines in eligible individuals above the age of 18 years. The EUA was issued for the Pfizer-BioNTech vaccine in children between 5 and 11 years of age on October 29, 2021. On November 19, 2021, the FDA amended the EUAs for Moderna and Pfizer-BioNTech COVID-19 vaccines to allow for the use of a single booster dose after completion of primary vaccination with any FDA-authorized or approved COVID-19 vaccine.
On November 29, 2021, the CDC recommended that everyone 18 and older receive a booster shot six months after their initial Pfizer or Moderna series or two months after their initial J& J vaccine. On December 9, 2021, the FDA amended the EUA for the Pfizer-BioNTech COVID-19 vaccine to allow for booster doses six months after the initial series in 16 and 17-year-olds, and CDC recommended the same. The FDA revised the Fact Sheets for Healthcare Providers and Recipients of the Janssen (Johnson and Johnson) vaccine on December 14, 2021. Individuals with a history of thrombosis with thrombocytopenia (TTS) following the Janssen COVID-19 Vaccine or any other adenovirus-vectored COVID-19 vaccine are contraindicated, and the risks of TTS following vaccination have been updated.
On January 3, 2022, the FDA amended the EUA Pfizer-BioNTech vaccine to include children aged 12 to 15, shortens the time between booster doses to at least five months, and allows for a third primary dose for certain immunocompromised children aged 5 to 11. The FDA reduced the interval between booster doses of the Moderna COVID-19 vaccine to 5 months on January 7, 2022. On January 31, 2022, the FDA approved the COVID-19 vaccine Spikevax (Moderna) as a two-dose primary series for people aged 18 and up. For the third primary series dose and booster dose, the EUA remains in effect. On March 29, 2022, the FDA approved a second booster dose of the Pfizer-BioNTech or Moderna COVID-19 vaccines for older and immunocompromised people. In addition, FDA limits the use of the Janssen (J&J) vaccine to certain individuals starting May 5, 2022, and a fact sheet for healthcare providers, recipients, and caregivers updated on the risk of blood clots with low levels of blood platelets.
Approved COVID-19 Vaccines:
1) Pfizer, BioNTech, and Fosun Pharma - The pharmaceutical company Pfizer, in collaboration with BioNTech (a German biotech company) and Fosun Pharma, developed a two-dose mRNA vaccine (Tozinameran or BNT162b2). After conducting trials on children and adults on 9th November, the company's data showed that the vaccine was 90 % effective. The FDA then reported that the Pfizer vaccine, after the first dose, gave some protection and almost full protection after the second dose on 8th December, and on 11th December, this vaccine was given EUA by the FDA. Reports showed an allergic reaction in a healthcare worker. The usage of this vaccine was recommended for people who are over 16 years of age. The sites that got approved to administer vaccinations in Alaska declared that they must have medications on hand to deal with an allergic response. They began testing this vaccine in children under 12 years to expand the age range, and the first shots were administered to volunteers on 24th March 2021. Although the study is still ongoing, the FDA has issued EUA for this vaccine in children between the ages of 5 and 11 years, stating that the benefits outweigh the potential risks.
2) Moderna (National Institutes of Health) - It is a two-dose mRNA vaccine (mRNA-1273) that began testing in March 2020. In August, the company's data showed a favorable immune response in 10 people between the ages of 56 and 70 and over the age of 70. In November, reports indicated the vaccine to be 94 % effective. And in mid-December 2020, this vaccine was given EUA by the FDA. This vaccination is given in 2 doses at a time interval of 28 days. In clinical trials, common side effects were noted. They were only mild. These kinds of effects were noted in the first seven days after vaccination. The vaccines do not contain any live coronavirus, so it is impossible to develop COVID-19 due to a vaccination.
3) Gamaleya Research Institute - It is a Russian institute that developed a vaccine (Sputnik V or Gam-COVID-Vac) that has two components, a recombinant adenovirus type (rAd26) and type 5 (rAd5) vectors. In August 2020, the vaccine received a "conditional registration certificate." The clinical trial in Russia involved 40,000 volunteers, and clinical trials have been announced in the UAE, India, Venezuela, and Belarus. The results of phase I and II trials found that the vaccine showed an immune response with mild side effects. The Sputnik V vaccine is 91.4 % efficient with mild side effects, and its vaccine efficacy against severe cases of Coronavirus is 100 %. High efficacy and immunogenicity, and safety results were obtained in phase III trials, including those in the elderly group. After ensuring all the safety standards, the Data and Safety Monitoring Board (DSMB) of India has recommended a shift to phase III from phase II. Phase III approval for conducting trials in India was approved. Sputnik V depends on the virus’s genetic instructions for developing the spike protein. Sputnik V uses double-stranded DNA, unlike the Pfizer-BioNTech and Moderna vaccines, which build the instructions in a single-stranded RNA.
4) Sinovac Biotech - This is a Chinese company that developed an inactivated SARS-CoV-2 vaccine (CoronaVac). The phase III trials began in Brazil, Indonesia, and Turkey. The vaccine was granted emergency approval by the Chinese government for use on individuals at high risk of developing severe COVID-19 infection. Initial researchers in Brazil found that this vaccine was 78 % effective. Later, the percentage was adjusted to 50.4 %. Sinovac has provided 160 million vaccine doses to 18 countries and territories, including China, with over 70 million doses administered. Sinovac said that the COVID-19 vaccine is safe for children between the ages of 3 to 17. Once administered, two recipients acquired high fevers in response to the vaccine, one a 3-year-old and a 6-year-old. The rest of the trial subjects felt only mild symptoms.
5) Wuhan Institute of Biological Products and Sinopharm - The vaccine BBIBP-CorV, an inactivated virus vaccine, is being tested by the Chinese company Sinopharm and developed by the Wuhan Institute of Biological Products. As the phase I clinical trial showed positive results, phase III trials began first in UAE and then in Morocco and Peru. Bahrain and UAE have already approved the vaccine for use. Sinopharm published on 30 December 2020 stage three trials of the vaccine and revealed that it was 79 % effective - more inferior than that of Pfizer and Moderna. However, the United Arab Emirates, which supported the Sinopharm vaccine earlier this month, said that the vaccine was 86 % effective, according to interim results of its stage three trial.
6) Bharat Biotech, Indian Council of Medical Research, and Indian National Institute of Virology - The inactivated virus vaccine (BBV152 or Covaxin) developed by the Indian company Bharat Biotech in collaboration with the Indian National Institute of Virology began the phase III trial in October. The report on Phase I trials showed the vaccine to be safe and produce antibodies against SARS-CoV-2. More than 26,000 participants were involved in phase III trials, and now Covaxin has been declared the first official vaccine in India. This whole virion-inactivated COVID-19 vaccine candidate confirmed a temporary vaccine efficiency of 81% in its Phase 3 clinical trial. The trials comprised 25,800 subjects, the largest ever conducted in India, in conjunction with the Indian Council of Medical Research.
7) AstraZeneca and the University of Oxford (Covishield in India) - In April 2020, AstraZeneca and the University of Oxford announced the development of a recombinant adenovirus vaccine (AZD1222), which was based on a chimpanzee adenovirus that carries coronavirus proteins in the body. Phase III clinical trials began in Brazil, the US, and South Africa in August. When a volunteer developed transverse myelitis (a spinal inflammatory disorder), the study was halted in September 2020. A week later, the trials restarted in the UK and Brazil, and the FDA authorized the US trial to resume in October 2020. It was reported in November 2020 that the vaccine produced a strong immune response in a clinical trial involving participants over 70 years of age. But, the data released on 8th December 2020 showed that the vaccine was only 70 % effective. The efficiency was identified to be around 62 % when they were administered in two separate and full doses. An increase in efficiency of up to 90 % was achieved when the vaccine was given as a half dose followed by a full dose. Leaving a more extended gap between the first and second doses enhances the jab's overall effectiveness - in a sub-group given the vaccine this way, it was observed to be 70 % effective after the first dose.
But recently, blood clots and unusual bleeding in a small number of vaccine recipients in European countries have cast doubt on its safety. However, no causative link has been observed between the patient's conditions and the vaccine. The reports have prompted more than a dozen countries to either partly or wholly suspend the vaccine's use while the cases are investigated. Most of the nations said they were doing so as a precaution until leading health agencies could review the cases. However, most countries continued using it after the European Medicines Agency conducted research and declared on 18th March 2021 that the AstraZeneca vaccine was safe and efficient. The EMA said the vaccine's benefits far outweighed the potential risks and pointed out that the post-vaccine blood clots rate was lower than the expected rate in the general population. After several days of uncertainty around the AstraZeneca COVID-19 vaccine trial results in the United States, the company confirmed efficacies of 76 % against symptomatic disease and 100 % against severe illness and hospitalization.
8) Johnson & Johnson - In late July 2020, Johnson & Johnson began a phase I/II trial in humans after their adenovirus vaccine (Ad26.COV2.S) showed positive results in monkeys. In September 2020, a phase III trial with 60,000 participants began to test their one-dose vaccine. Due to an unexplained illness in one of the participants, the trial was paused in October 2020. The study will resume in the US, and the company said that the vaccine would be ready for FDA approval by February 2021. The company still said it found no proof that the vaccine had caused the disease and declared on 23 October 2020 that it would continue the trial. On 29 January 2021, Janssen proclaimed safety and efficacy data from an interim investigation of ENSEMBLE trial data. The trial results showed the vaccine to be 66.9 % effective against moderate cases and 76.7 % effective against severe cases when the test was taken 14 days after getting the vaccination. While taken after 28 days of getting the vaccine, the efficacy in moderate cases was 66.1 % and 85.4 % in severe cases. A second Phase III clinical test called ENSEMBLE 2 began recording on 12 November 2020. ENSEMBLE 2 differs from ENSEMBLE in that it will analyze participants who will get two intramuscular (IM) shots of Ad26.COV2.S, on day 1 and the next on the 57th day.
In February 2021, the U.S. Food and Drug Administration announced an emergency use authorization (EUA) for the third vaccine for the restriction of coronavirus disease 2019 (COVID-19) induced by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The EUA supports the Janssen COVID-19 Vaccine to be administered (single-shot) in the U.S. for use in people who are above 18 years of age. Thailand also cleared Johnson & Johnson’s single-shot COVID-19 vaccine for local emergency use, the third manufacturer to win the approval. Johnson & Johnson vaccine has also got EUA by the FDA for administering booster doses in individuals above the age of 18 years who have got the primary doses of any FDA-approved or authorized vaccine.
9) CanSino Biologics - China's CanSino Biologics Inc., backed by the Chinese military, is also developing a potential COVID-19 vaccine. They are using an adenovirus Ad5 to carry coronavirus proteins into the cells. The protein elicits an immune response when combined with another compound called the adjuvant. This vaccine is called Ad5-nCoV or Convidecia. In July 2020, it was reported that the participants in the phase II trial showed a strong immune response to the vaccine. As older adults had a weaker response, two doses might be needed for them. The Chinese military approved the vaccine in June, and it was administered to the armed forces. As of December 2020, over 20,000 participants have enrolled for late-stage human trials in Pakistan, Saudi Arabia, and Russia. This vaccine has been approved for general use in China since February 25, 2021. Also, this vaccine has been authorized for emergency use in countries like Pakistan, Ecuador, Chile, Argentina, Moldova, Malaysia, Hungary, Indonesia, and Mexico. The manufacturers reported to the WHO that this vaccine has an efficacy of 63.7 % after 14 days of vaccination, and the efficacy reduced to 57.5 % when the tests were taken 28 days after getting the vaccine. However, the efficacy rate was found to be 96 % against severe COVID-19 infections. Also, they reported that there was an eight-fold increase in the antibody titers in the second dose as compared to the first dose.
10) Beijing Institute of Biological Products and Sinopharm - Sinopharm also tested another inactivated virus vaccine developed by the Beijing Institute of Biological Products. In June 2020, phase III trials began in the UAE and Argentina (in September). In September 2020, this vaccine was approved by the UAE to use on healthcare workers. The analysis report from the three clinical trials proved the efficiency to be about 86 %. On May 7, 2021, the WHO granted emergency use authorization for this vaccine. Also, this is the first vaccine to have a vaccine vial monitor on the vial indicating the safety of the vaccine for usage. The vial monitor acts as an indicator by changing its color when exposed to heat.
Ongoing COVID-19 Vaccine Projects:
1) Inovio - This pharmaceutical company designed the vaccine INO-4800, a nucleic-acid-based vaccine, in January 2020. Following authorization by the FDA, they started the human clinical trial in April 2020. After they got clearance from the FDA in November 2020, Phase I and Phase II of the trials were conducted, and satisfactory results were obtained. The results of phase II trials showed tolerability and immunogenicity in individuals above the age of 18 years. Now the authorization to conduct a phase III trial has been approved by Brazil. Inovio's DNA medicines release optimized plasmids instantly into cells intradermally or intramuscularly, employing Inovio's proprietary hand-held smart device called Cellectra. The Cellectra device uses a short electrical pulse to reversibly penetrate tiny pores in the cell to allow the plasmids to enter, succeeding a fundamental limitation of other DNA and other nucleic acid strategies, such as mRNA. Once inside the cell, the DNA plasmids allow the cell to generate the targeted antigen. The antigen is prepared naturally in the cell and triggers the desired T cell and antibody-mediated immune responses. Administration with the Cellectra device guarantees that DNA medicine is efficiently transferred directly into the body's cells, where it can work to stimulate an immune response.
2) Sanofi and GlaxoSmithKline (GSK) - These French and Britain pharmaceutical companies developed an adjuvanted protein vaccine. Initial results from a phase I/II clinical trial in December 2020 showed a poor immune response in older adults but a sufficient immune response in adults between 18 and 49. The phase III clinical trial of the vaccine is ongoing and is conducted in countries like India, Nepal, the United States, Kenya, Ghana, Columbia, and Honduras. A delay in the development of this vaccine is noted in order to enhance the results in older people. The Sanofi/GSK vaccine is a recombinant protein-based vaccine depending on the baculovirus commonly seen in moths. Pieces of the novel coronavirus are applied in sequence with the baculovirus to efficiently program the immune system to recognize better and fight COVID-19.
3) Sanofi and Translate Bio - The French drugmaker Sanofi is also working with Translate Bio, and they developed an mRNA vaccine in February 2020. Nonhuman trials conducted on monkeys and mice showed a strong immune response. The phase II trial results showed that there was about 91 % to 100 % neutralizing antibody seroconversion in individuals 14 days after the injection. The tolerability of this vaccine was similar to that of other unmodified mRNA vaccines, and there were no safety concerns. The company has planned not to pursue the phase III study of this mRNA vaccine.
4) Novavax - The SARS-CoV-2 recombinant spike protein nanoparticle with an adjuvant vaccine (NVX-CoV2373) developed by Novavax received massive funding from the Coalition for Epidemic Preparedness Innovations (CEPI). The virus proteins are attached to microscopic particles to form this vaccine. In August 2020, a phase II trial was launched in South Africa, and a phase III trial began in the UK a month later. In September 2020, a COVID-19 vaccine manufacturing agreement was made with the Serum Institute of India to produce over 2 billion doses annually. Novavax was eliminated from the emergent facility because of the lack of personal manufacturing units. On November 10, 2021, the Novavax vaccine was provided guidance from the CDC; the participants of phase III clinical trials of the vaccine were considered fully vaccinated when they received the full series of this COVID-19 vaccine. The manufacturers are planning to submit this vaccine for EUA from the FDA.
5) University of Queensland and CSL - The university, along with CSL, developed the UQ-CSL v451 COVID-19 vaccine. Phase I trial of this vaccine showed a robust response towards the virus. The vaccine was developed by growing viral proteins in cell cultures. No serious side effects or safety concerns were reported in the 216 participants. Still, as participants returned false-positive test results for HIV, it was decided that the vaccine would not go into phase II/III clinical trials. Therefore, this vaccine is under redevelopment, and they are trialing 20 different alternatives to the HIV proteins which do not interfere with the diagnosis.
6) Medicago and GlaxoSmithKline (GSK) - GSK and Medicago developed a COVID-19 candidate vaccine combining recombinant Coronavirus Virus-Like Particles (CoVLP) with an adjuvant system. CoVLP mimics the structure of the SARS-CoV-2 virus, resulting in an immune response. Pre-clinical results using this single-dose vaccine demonstrated high levels of neutralizing antibodies. Medicago, a biopharmaceutical company and GlaxoSmithKline (GSK), started Phase III clinical research of Medicago's plant-derived COVID-19 vaccine candidate in sequence with GSK's pandemic adjuvant as part of the ongoing Phase II/III study.
7) CureVac and Coalition for Epidemic Preparedness Innovations (CEPI) - This company has developed an mRNA vaccine (Zorecimeran or CVnCoV), which showed antibody responses comparable to the one found in recovered COVID-19 patients. Phase IIb and III trials were initiated in December 2020. Nearly 35,000 participants were included in this trial. CVnCoV is an mRNA vaccine that encodes a minimum piece of the coronavirus spike protein and stimulates the immune system against it. CVnCoV technology does not associate with the human genome under typical conditions, that is, in the absence of example, an active retrovirus infection.
8) Needle-Free COVID-19 Vaccines or Inhaled Vaccine -
a. CanSinoBIO
The company had not yet published news about the inhaled version of the vaccine. According to the company, previous trials involving the injectable product had shown 95.47 % efficacy in preventing severe COVID-19 disease two weeks post-vaccination. The currently-approved COVID-19 vaccines on the market are delivered as intramuscular injections in the deltoid muscle. However, some researchers have already studied different vaccine administration techniques. The National Medical Products Administration approved the inhaled vaccine trial. Experts have assumed that the next generation of COVID-19 vaccine may comprise needle-free options, potentially eliminating hesitancy among groups with sensitivity to needles. Phase I trials have reported that the two doses of inhaled CanSinoBio vaccine have provided efficiency similar to that of a single-dose injected vaccine.
b. Nasal Spray Vaccine (Oxford University):
Oxford University said on Thursday that it was beginning a study to test the immune responses of a nasal administration of its COVID-19 vaccine generated with AstraZeneca, with 30 healthy volunteers aged 18 to 40 for the initial experiment. British researchers last September said that they would test inhaled versions of COVID-19 vaccine candidates produced by Oxford University and Imperial College to see whether they present any localized immune response in the respiratory tract.
c. BioRxiv (Nasal Spray Vaccine):
The nasal spray vaccine is produced based on a regular poultry virus called the Newcastle Disease Virus (NDV), which can replicate in humans but does not harm. The research team directed NDV to create the spike proteins of the SARS-CoV-2 virus to prime the body's immune system to combat the coronavirus. The findings were announced recently on BioRxiv, a preprint server for analysis that has not yet been peer-reviewed.
9) Oral COVID-19 Vaccine -
a. Oravax - Israeli-American Pharmaceutical Company
Oramed Pharmaceuticals (ORMP), along with Oravax Medical (ORVX), are working on oral COVID-19 vaccines. The Oravax vaccine is a virus-like particle (VLP) triple antigen vaccine that targets three structural proteins. This can provide protection against emergent coronavirus mutations. The company has gained approval for phase I clinical trials in Israel and South Africa. It has also been applied to experiments in multiple countries, including the United States, Europe, and Mexico. It also hopes to target Africa, where such an oral vaccine could be essential. An Israeli-American pharmaceutical company is preparing to start a Phase I clinical trial for what can become the world's leading oral COVID-19 vaccine. Oravax is a joint attempt by two firms: the Israeli-American company Oramed and the Indian company Premas Biotech. Its press release on Friday said that investigations could begin by June. Oral vaccines are an option being evaluated for "second-generation" vaccines, which are intended to be more scalable, more comfortable to administer, and simpler to share. Vaccinating against COVID-19 could shortly be as easy as drinking a glass of water following an Israeli-American firm published plans to trial a tablet vaccine. Oravax said that a strong oral delivery method would significantly reduce the administration costs and enable people to take the vaccine independently. This clinical study will start before the end of June this year.
b. Oramed Pharmaceuticals and Premas Biotech
Oramed Pharmaceuticals Inc. is a clinical-stage pharmaceutical company based on Hadassah-University Medical Center technology. It has declared a joint venture with India-based Premas Biotech to produce a novel oral vaccine. Collectively they built the company Oravax Medical Inc. The vaccine depends on Ora med's "POD" oral transmission technology and Premas's vaccine technology. Oramed's technology can be used to orally deliver several protein-based therapies, which would otherwise be administered by injection. Oramed is in the middle of Phase III clinical trials in the United States Food and Drug Administration of an oral insulin pill for Type 1 and Type 2 diabetes.
c. Galilee Research Institute's Biotechnology Group
In February 2020, immediately after the commencement of the COVID-19 pandemic, another Israeli team started developing what they considered would be an oral coronavirus vaccine. Experts from the Galilee Research Institute's biotechnology group believe that their vaccine will reach testing soon.
10) The Gennova mRNA Vaccine HGCO19 - Gennova biopharmaceuticals, a biotechnology company in India, worked on the nation’s first mRNA vaccine. After the phase I study, the clinical data concluded that the HGCO19 vaccine was tolerable, safe, and immunogenic. The Central Drugs Standard Control Organisation (CDSCO) is entitled to evaluate the safety and effectiveness of the vaccine. Phase II and phase III clinical trials were approved to be conducted at 10 to 15 and 22 to 27 sites, respectively. The company is aiming to roll out the indigenous vaccine before April 2022. Gennova's mRNA vaccine is known to overcome the limitations of the Pfizer and Moderna vaccines, as the latter has to be stored under sub-zero temperatures. The HGCO19 vaccine can be stored in ordinary refrigerators and modified to be compatible with new variants. Genova HGCO19 vaccine works on self-amplification technology, where it contains a code for the virus enzyme and enables it to create multiple copies of viral RNA. This is an added advantage as the self-amplifying mRNA vaccine can produce viral proteins quickly, leading to a low dose regime. The Genova vaccine promises a new ray of hope, especially for immunogenicity against new variants like the Omicron.
11) Bharat Biotech BBV154 Intranasal Vaccine - The BBV154 is a novel adenovirus vectored intranasal COVID-19 vaccine. It was developed by Bharat Biotech, Precision Virologics, and the Washington University of medicine. In August 2021, phase II and phase III clinical trials were approved. After a single dose administration in animal models, the vaccine demonstrated viral clearance and superior protection against the virus. The reports were evaluated by the Central Drugs Standard Control Organisation (CDSCO). The vaccine triggers the immune response at the site of infection and neutralizes antibody reactions. The intranasal vaccine has several advantages, it is non-invasive, needle-free, easy to administer, highly compliant, and eliminates associated needle risks. It is especially suited for children.
There are various other vaccines, such as INO-4800, which has completed the phase I trial, Lunar-COV19/ARCT-021, have completed the phase I trial and is under phase II trial, LV-SMENP-DC; and EpiVacCorona is expected to release the phase I report shortly. About 50 vaccines are in early development over the biopharma landscape. Researchers are investigating ten different vaccine approaches, said Jim Mayne, vice president of science and regulatory advocacy at PhRMA.
Repurposed Vaccines Against SARS-CoV-2:
Using an already approved vaccine (for some other infection) for protection against the new Coronavirus is called a repurposed vaccine. An Australian Institute (the Murdoch Children's Research Institute) is conducting a phase III trial using the bacillus Calmette-Guérin (BCG) tuberculosis vaccine to see its capacity to prevent COVID-19 in Australia, the Netherlands, Brazil, Spain, and the UK.
It is also believed that the polio vaccine might help the immune system fight SARS-CoV-2, and the measles, mumps, rubella (MMR) vaccine to protect against inflammation and sepsis due to COVID-19. Nothing has been proven yet.
Frequently Asked Questions:
1) Are Moderna and Pfizer's COVID-19 Vaccines Given in Two Doses?
Yes, both Moderna and Pfizer vaccines are given in two doses. The time between the two doses is 21 days for Pfizer's vaccine and 28 days for Moderna.
2) How Effective Is the Pfizer COVID-19 Vaccine?
The Pfizer vaccine is 95 % effective at preventing symptomatic COVID-19 cases, according to the FDA.
3) How Effective Is the Moderna COVID-19 Vaccine?
According to the FDA, the Moderna vaccine is 94.1 % effective at preventing symptomatic COVID-19 cases.
4) Can Patients Currently Infected With COVID-19 Get Vaccinated?
Infected patients carry the risk of spreading the virus during vaccination. To avoid this, vaccinations should be scheduled 14 days after the resolution of symptoms. However, many countries recommend that infected people wait for three to six months due to a shortage of vaccines.
5) Should Previously COVID-19 Infected People Get Vaccinated?
Yes, people who have already recovered from COVID-19 can get vaccinated. Such people already might have some level of immunity against the virus, but doctors are still advising them to get vaccinated when the vaccine becomes available to them.
6) Why Should People Who Have Had COVID-19 Still Be Vaccinated?
A few COVID-19-recovered patients do not seem to have a good immune response, and some reinfection cases have been reported, which is why getting vaccinated even if a person was infected previously is the best thing to prevent COVID-19.
7) Should a Person Continue to Wear a Mask After COVID-19 Vaccine?
Getting the COVID-19 vaccine will prevent symptomatic COVID-19 infection, but scientists do not know if it can prevent a person from spreading the virus to others. Until we know for sure, keep wearing the mask when going to crowded places to protect others who might not have been vaccinated yet.
8) Can a Person Spread the New Coronavirus if They Get Vaccinated?
Even after getting vaccinated, you could still possibly carry and spread the new Coronavirus to others. So wear masks, maintain social distancing, and practice frequent hand-washing to protect others until the majority of the population gets vaccinated.
9) Can a Pregnant or Breastfeeding Woman Get the COVID-19 Vaccine?
There is no data available to determine if the COVID-19 vaccine poses a risk to pregnant and breastfeeding women. In the United Kingdom, pregnant and breastfeeding women are excluded from vaccination programs, and in the United States, only women who volunteer will be given the vaccine. The COVID-19 vaccines from Moderna and Pfizer are active in pregnant women, boosting their immune response and even transferring protective antibodies to their babies, found in a new study. Of that, Eighty-four were pregnant, and 31 were lactating. According to the researchers from centers including Harvard, MIT, Brigham, and Women's Hospital, the pregnant and lactating women had a stronger immune response to the vaccines compared to the 16 women who were not pregnant or lactating. Examining the umbilical cord blood and the placenta, they found that the babies born to women who had obtained the vaccine had "strikingly higher" levels of COVID-fighting antibodies than babies born to women who had previously had COVID-19.
10) What Are the Common Side Effects of the COVID-19 Vaccine?
The common side effects noted so far during various drug trials are pain and swelling at the site of infection, fever, chills, headaches, and tiredness.
11) How Soon After Taking the COVID-19 Vaccine a Person is Immune?
It can take a few weeks for the body to build immunity after getting vaccinated. So, it is possible to get infected with the new virus just before or after vaccination.
12) Who Will Get Vaccinated First?
Healthcare workers and front-line workers are at the highest risk of exposure to COVID-19. They are given high priority for COVID-19 vaccination. The family members of healthcare workers need to get the vaccination according to the standard protocol of the government.
13) Will COVID-19 Vaccine Provide Prolonged Protection?
COVID-19 vaccines with WHO Emergency Use Listing (EUL) offer varying levels of protection against infection, mild disease, severe disease, hospitalization, and death. Thousands of scientists around the world are working to better understand how new virus mutations and variants affect the effectiveness of the various COVID-19 vaccines. Although the WHO-approved COVID-19 vaccines are extremely effective at lowering the risk of serious illness and death, no vaccine is 100% effective. Even if they have been immunized, a small number of people will become ill from COVID-19. There is currently little information available about the risk of vaccinated people spreading the virus to others if they become infected. As a result, it is critical to maintain public health and social measures.
14) Is It Compulsory to Get the COVID-19 Vaccine?
A person can choose not to get vaccinated, and it is totally voluntary. But, it is advisable to receive all the doses of the COVID-19 vaccine for protection against the infection and to prevent the spread to others.
