Here’s all you need to know about the top candidates in the COVID-19 vaccine race

The pandemic has upended the health system and economy worldwide. Pharma companies and drugmakers are racing against time – and each other – to successfully develop a vaccine. Here’s a closer look at the top candidates in the coronavirus vaccine race

COVID-19 has infected 218 countries and territories around the world, with 62.5 million cases and 1.4 million deaths. With second and third waves threatening further contagion, researchers, pharma companies, and drugmakers across the world are racing to find the cure to coronavirus.

All eyes are now on pharmaceutical players, who are working day in and out to develop, test, and produce a COVID-19 vaccine. A WHO report published earlier this month revealed that 48 vaccine candidates are at present undergoing clinical trials across the world.

What should the vaccine deliver? The WHO wants at least 70 percent efficacy in trials while the US Food and Drug Administration (USFDA) is willing to go down to 50 percent. The European Medicines Agency, meanwhile, has suggested that it may accept a lower efficacy level.

YourStory brings you an updated list on the popular vaccine candidates being tested, their current status, and where India stands in the vaccine race.

Illustration Credit: Daisy Mahadevan, YS Design

National vaccine candidates 

Amidst the rising coronavirus cases in India, about five companies are in the advanced stages of developing a COVID-19 vaccine. During a virtual meeting with state governments, Prime Minister Narendra Modi said: “Five vaccine candidates are in advanced stages of development in India, out of which four are in Phase II/III and one is in Phase-I/II trials.”

The nationally developed vaccine candidates in advanced stages include:

Bharat Biotech 

Hyderabad-based Bharat Biotech is developing Covaxin in collaboration with the ICMR - National Institute of Virology (NIV). The vaccine candidate is currently undergoing Phase III human trials with 26,000 participants. It has successfully completed Phase I and II with 1,000 subjects and has been reportedly found to be safe without any major adverse events.

“This indigenous, inactivated vaccine is being developed and manufactured in Bharat Biotech's BSL-3 (Bio-Safety Level 3) biocontainment facility. COVAXIN™ is a highly purified and inactivated vaccine, manufactured in a vero cell manufacturing platform with a safety track record of more than 300 million doses supplied,” the company said in an official statement.

According to a report by India Today, Bharat Biotech’s vaccine candidate is expected to be 60 percent effective against SARs-Cov-2 on the basis of trials done till now. The company aims to launch the vaccine by the second quarter of 2021.

Price: Not Announced

Storage: 2°C to 8°C

Zydus Cadila  

Apart from Bharat Biotech, the Indian government is also closely following Ahmedabad-based pharmaceutical company Zydus Cadila’s vaccine candidate ZyCov-D.

Earlier this month, a report by MoneyControl revealed that the company completed its Phase II trials and was scheduled to submit the data to the Drug Controller General of India (DCGI) this month. Zydus is planning to begin Phase III trials on nearly 15,000-20,000 participants in December.

The preliminary results had thrown up no concerns. The report said Zydus’ candidate is a DNA vaccine comprising genetic material of the COVID-19 virus, which will instruct the human cells to produce SARS-CoV2 antigen - thereby inducing an immune response. The vaccine does not use live virus.

Zydus recently also announced that it had completed Phase II trials of its biological therapy, Pegylated Interferon alpha-2b or ‘PegiHepTM,’ in 40 COVID-19 patients. 

Ninety-five percent of subjects who received a single dose of PegiHepTM along with the Standard Of Care (SOC), became virus-free as assessed by RT-PCR on day 14 and showed significant clinical improvement over patients in the reference arm, who received only the SOC and only 68 percent [of them] showed an improvement in clinical symptoms and became RT-PCR negative,” the company said in an official statement. 

The company revealed that PegiHepTM was not a new therapy. It had been approved for treating Hepatitis C and was launched in the Indian market in 2011.

“We continue to look at safe and efficacious options in the treatment and management of COVID-19. Pegylated Interferon alpha-2b has shown the potential to reduce virus titres when given earlier in the disease, and we will like to explore this biological option further. We are hopeful of reinforcing our treatment options to fight COVID-19,” said Dr Sharvil Patel, Managing Director, Cadila Healthcare Ltd in a statement.

Price: Not Announced

Storage: 2°C to 8°C

Biological E

Hyderabad-based vaccine manufacturer Biological E earlier this month announced that the company had initiated Phase I and II human clinical trials of its COVID-19 subunit vaccine candidate in India after receiving approval from the Drugs Controller General of India (DGCI).

This vaccine candidate is being developed in partnership with US-based Baylor College of Medicine and US-based Dynavax Technologies Corporations.

“Biological E's Phase I/II clinical trial will evaluate the safety and immunogenicity of the vaccine candidate consisting of the Receptor Binding Domain of the Spike Protein of SARS-CoV-2 at three dose levels adjuvanted with CpG 1018 plus alum, in about 360 healthy subjects in the age range of 18 to 65 years,” the company said in a statement.

The vaccination schedule comprises two doses for each participant and will be administered 28 days apart. The results of this clinical trial are expected to be announced by February 2021

Price: Not Announced

Storage: Not Announced

International vaccine candidates


It is safe to say that the world is pinning their hopes on UK-based pharmaceutical company AstraZeneca and Oxford University’s vaccine candidate, AZD1222.

The company recently announced its Phase III interim results from the UK and Brazil, showing an average efficacy of 70 percent. 

However, the results revealed that the vaccine's efficacy was different in two different dose regimens. The efficacy was 90 percent when the first dose was halved and a standard second dose was administered; two full doses showed an efficacy of 62 percent.

Both AstraZeneca and Oxford University acknowledged a manufacturing error in the preliminary results on why a group was administered half the dose the first time. But surprisingly this resulted in higher efficacy. Media reports suggest the company will have to conduct additional trials for clarity on the data.

In India, a version of the Oxford-AstraZeneca vaccine, Covishield, is undergoing trials at Pune-based Serum Institute of India (SII). Media reports revealed that SII may have to conduct additional tests for Covishield and take approvals to market another version, which might be more effective than the current one. This additional test stems from the AZD1222 preliminary results. 

In an official statement, SII said the vaccine was safe and Indian trials were running smoothly. "The Indian trials are running smoothly with strict adherence to all necessary processes and protocols. So far, there are no concerns. However, we are going through the data that is available and will make further statements, if needed," SII said.

Price: Yet to be determined; expected to be lower than Rs 1,000

Storage: 2°C to 8°C

Pfizer and BioNTech

Global drug manufacturers Pfizer and BioNTech concluded the Phase III study of their mRNA-based COVID-19 vaccine candidate BNT162b2. According to the companies, their vaccine candidate proved to be 95 percent effective, including in adults aged over 65 years.

The companies said it had requested the US Food and Drug Administration (FDA) for Emergency Use Authorisation (EUA) of the vaccine. 

“Filing in the US represents a critical milestone in our journey to deliver a COVID-19 vaccine to the world and we now have a more complete picture of both, the efficacy and safety profile of our vaccine, giving us confidence in its potential. We look forward to the upcoming Vaccines and Related Biological Products Advisory Committee discussion and continue to work closely with the FDA and regulatory authorities worldwide to secure authorisation of our vaccine candidate as quickly as possible,” said Dr Albert Bourla, Pfizer Chairman and CEO. 

According to the official statement, the companies expect to produce up to 50 million doses in 2020 globally and up to 1.3 billion doses by the end of 2021. However, the vaccine is yet to get approvals for distribution anywhere in the world.

Indian Union Minister Dr Harsh Vardhan reportedly said India may not need the Pfizer-BioNTech vaccine as several other candidates are being tested. He said the company had no linkages with India for manufacturing the vaccine, and would need to cater to its own countries upon receiving approval.

Price: Reportedly $20 per dose

Storage: -70°C


On November 16,US-based biotech company Moderna announced that its vaccine candidate, mRNA-1273 appeared to be 94.5 percent effective against COVID-19, according to preliminary data from the company's still ongoing Phase III clinical trials.

According to the company, mRNA-1273 is an mRNA vaccine that encodes a prefusion stabilised form of the Spike (S) protein, co-developed by Moderna and investigators from NIAID’s Vaccine Research Center. 

“Based on these interim safety and efficacy data, Moderna intends to submit for an Emergency Use Authorization (EUA) with the US Food and Drug Administration (FDA) in the coming weeks and anticipates having the EUA informed by the final safety and efficacy data (with a median duration of at least two months). Moderna also plans to submit applications for authorisations to global regulatory agencies,” the company said in a statement.

Price: Expected to be priced at $37

Storage: -20°C

Gamaleya National Research Institute of Epidemiology and Microbiology

Russia-based Gamaleya National Research Institute of Epidemiology and Microbiology and Russian Direct Investment Fund’s (RDIF) vaccine candidate, Sputnik V, is the country’s first registered COVID-19 vaccine. Earlier this month, the institute announced that the vaccine candidate showed 91.4 percent efficacy, depending on the second interim analysis of Phase III clinical trials.

“Preliminary data from volunteers obtained 42 days after the first dose (corresponds with 21 days after the second dose) indicates an efficacy of the vaccine above 95 percent,” an official statement from Gamaleya and RDIF noted.

According to the statement, the uniqueness of the vaccine candidate lies in the use of two different vectors based on the human adenovirus, enabling a stronger and longer-term immune response as compared to vaccines using one and the same vector for two doses. 

RDIF has partnered with manufacturers in India, Brazil, South Korea, China, and four other countries for manufacturing and distribution of the vaccine, following the announcement of final results and approvals.

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.

Price: Free for Russia; less than $10 for international markets

Storage: -18°C

Johnson & Johnson

On October 23, Johnson & Johnson’s pharmaceutical arm Janssen announced its plans to resume the Phase III ENSEMBLE trial of its vaccine candidate JNJ-78436735, also known as Ad26.COV2.S. The company is at present preparing to resume trials in the US after consultation with the US FDA.

The company had to temporarily pause trials on October 12 after one of the study participants was analysed with an unexplained illness. However, it is now resuming trials after a thorough examination showed no evidence to prove that the vaccine candidate was the reason for the illness.

“After a thorough evaluation of a serious medical event experienced by one study participant, no clear cause has been identified. There are many possible factors that could have caused the event,” Johnson and Johnson said in a statement.

The company added that the Data Safety and Monitoring Board (DSMB) overseeing the ENSEMBLE study had recommended resuming trial recruitment. 

Price: Likely to be priced at $10

Storage: 2°C to 8°C

Edited by Teja Lele Desai