New Delhi: With the coronavirus pandemic continuing to claim thousands of lives across the globe every day, the Indian Council of Medical Research (ICMR) has decided to fast-track clinical trials of the indigenous Covid-19 vaccine, which it is producing with the Bharat Biotech International Limited (BBIL).
Not only ICMR, but the scientific community and medical researchers across the world are working on war-footing to come up with a vaccine for the deadly virus as early as possible.
ThePrint brings you a list of all the vaccine candidates currently undergoing clinical trials around the world.
Developed by the University of Oxford in collaboration with pharmaceutical company AstraZeneca, the ChAdOx1-S vaccine is currently undergoing Phase 3 clinical trials in human volunteers.
The vaccine contains a virus called ChAdOx1 — a weakened and non-replicating version of a common cold virus (adenovirus) — which has been engineered to express the SARS-CoV-2 spike protein.
The spike protein of the novel coronavirus allows it to enter human cells. The presence of this protein also triggers immune response in a body.
The Oxford vaccine has already been evaluated in a large clinical trial in the UK where more than 4,000 participants have been enrolled.
In addition to a South African study of the vaccine, similar and related studies are about to start in Brazil as well. An even larger study of the same vaccine, consisting of up to 30,000 participants, is being planned in the US too.
Ad5-nCoV by CanSino
Developed jointly by Chinese vaccine company CanSino Biologics and the Beijing Institute of Biotechnology in the Academy of Military Medical Sciences, the vaccine has reportedly shown promising results in the Phase 2 clinical trials, though they are yet to be published.
Like the Oxford vaccine, this uses a weakened adenovirus. The vaccine has also been approved for clinical trials in Canada.
mRNA-1273 by Moderna
The mRNA-1273 vaccine candidate, developed by US-based biotechnology company Moderna, has started Phase 2 clinical trials.
The mRNA is a molecule that genetically encodes a set of instructions, based on which cells make proteins and send them to various parts of the body.
Medicines based on mRNA technology take advantage of normal biological processes of the body to create desired therapeutic effects.
Instead of introducing protein drugs to the body, mRNA drugs trigger cells to produce the required proteins to fight off an infection. This method prevents the immune-system response from kicking in and hampering the effect of a drug.
INO-4800 by Inovio
Developed by US-based Inovio Pharmaceuticals in collaboration with International Vaccine Institute, the DNA vaccine injects a part of the genetic code of the virus, which allows cells to produce antigens — a molecule present on the outer surface of the virus.
In this case, the DNA vaccine helps produce the spike protein, and triggers cells to produce antibodies against the protein.
Vaccine by Wuhan Institute of Biological Products
Developed by the Wuhan Institute of Biological Products and Chinese pharmaceutical company Sinopharm, the inactivated novel coronavirus (2019-CoV) vaccine is undergoing Phase 1 and Phase 2 trials simultaneously in China.
This vaccine contains an inactivated form of the coronavirus to trigger immune reaction. The inactivated viruses are grown in lab culture, usually in vero cells — kidney cells extracted from an African green monkey. These viruses lose the capacity to cause infection.
Inactivated Covid-19 vaccine by Sinopharm
A similar inactivated novel coronavirus vaccine, also developed by Sinopharm in conjunction with the Beijing Institute of Biological Products, is simultaneously undergoing Phase 1 and Phase 2 trials in China.
The vaccine candidate known as CoronaVac has already completed Phase 1 and Phase 2 trials and is preparing to proceed to Phase 3 trials in China. This is also an inactivated coronavirus vaccine.
SARS-CoV-2 rS by Novavax
The SARS-CoV-2 rS, developed by US-based vaccine development company Novavax, is undergoing simultaneous Phase 1 and Phase 2 trials in Australia.
The full length recombinant SARS CoV-2 glycoprotein nanoparticle vaccine involves selecting a part of the genetic sequence of the virus that produces antigens (in this case the spike protein). This sequence is then introduced in baculoviruses — pathogens that attack insects.
These modified baculoviruses are then made to infect insect cell culture, so that the cells can produce proteins that are similar in structure to the viral antigens. These proteins are purified and converted into particles similar to that of the novel coronavirus.
This tricks the immune system to produce antibodies against the coronavirus.
The vaccine is administered with Matrix M, which increases the neutralising antibodies and induces long-lasting B cells, a type of white blood cell that enhances immunity.
BNT162-01 by BioNTech and Pfizer
The BNT162-01 vaccine candidate, developed by BioNTech RNA Pharmaceuticals, Shanghai Fosun Pharmaceutical and Pfizer, is undergoing simultaneous Phase 1 and Phase 2 trials in Europe.
This too is an mRNA vaccine, similar to the vaccine technology used by Moderna.
Vaccine by Chinese Academy of Medical Sciences
Another inactivated SARS-CoV-2 vaccine developed by the Institute of Medical Biology, Chinese Academy of Medical Sciences, is undergoing Phase 1 trial in China.
This vaccine is currently being tried in three different dosages in different groups of study participants.
GX-19 by Genexine consortium
The vaccine candidate, GX-19, has been developed by a consortium consisting of Genexine, Binex, International Vaccine Institute, Genbio, the Korea Advanced Institute of Science & Technology (KAIST), and the Pohang University of Science & Technology (POSTECH).
Undergoing Phase 1 clinical trial in South Korea, GX-19 is a DNA vaccine with a mechanism similar to Inovio’s vaccine candidate.
Gam-COVID-Vac Lyo by Gamaleya Research Institute
Undergoing Phase 1 trials in Russia, the Gam-COVID-Vac Lyo developed at the Gamaleya Research Institute in Russia is an adenovirus vaccine similar to the CanSino.
SCB-2019 by Clover, GlaxoSmithKline, Dynavax
The SCB-2019 vaccine candidate, developed by Shanghai-based Clover Biopharmaceuticals, UK-based GlaxoSmithKline and US-based Dynavax Technologies, is under Phase 1 clinical trials in Australia.
The vaccine is made up of S-Trimer protein that resembles the coronavirus spike protein and hence triggers the immune system to produce antibodies.
During the trials, one group will receive the vaccine combined with an adjuvant developed by GSK, which reduces the amount of proteins needed to create effective vaccines.
Another group will get the vaccine with an adjuvant developed by Dynavax, combined with alum — which acts as a mild irritant to trigger the immune response.
RBD-Dimer vaccine by Anhui Zhifei Longcom
Developed in collaboration with the Institute of Microbiology, Chinese Academy of Sciences, Zhifei Longcom’s adjuvanted recombinant protein (RBD-Dimer) vaccine is currently in Phase 1 clinical trial in China.
For this vaccine, Chinese Hamster Ovary (CHO) cells were used to produce a modified form of the coronavirus spike protein that triggers a more pronounced immune response.
COVAX19 by Vaxine Pty Ltd & Medytox
COVAX19 is a vaccine candidate developed by Australian biotechnology company Vaxine Pty and a Korean pharma MedyTox. It is under the first phase of clinical trials in Australia.
This vaccine too contains modified form of the spike protein along with an adjuvant called Advax that enhances antibody and immune cell responses.
COVAC1 at Imperial College London
COVAC1, developed by the Imperial College London, is currently undergoing Phase 1 clinical trials.
This is a self-amplifying ribonucleic acid (saRNA) vaccine. The principle of this vaccine is similar to the mRNA vaccine. However, saRNA are able to make copies of themselves much faster and hence able to produce more proteins.
CVnCoV by CureVac
The CVnCoV vaccine is undergoing Phase 1 clinical trial in multiple centres in Germany. The mRNA vaccine is developed by German pharma CureVac.
mRNA vaccine by PLA academy, Walvax Biotech
The People’s Liberation Army (PLA) Academy of Military Sciences and Walvax Biotech have developed an mRNA vaccine.
It is currently undergoing Phase 1 clinical trial in China.
Apart from this, there are at least 129 known vaccine candidates all over the world currently at the preclinical stages of development.