WebMD Health News

COVID-19 Vaccine: Latest Updates

photo of virus 3d render blue

Editor's note: This article was  last updated Sept. 23, 2020.

August 7,  2020 – Public health experts are hoping one or several vaccines for COVID-19 will be ready by 2021. Close to 200 vaccines for the disease are under study, and several  candidates have moved to phase III human studies. That’s the final step to prove if the vaccine is safe and effective before it can get FDA approval.

To help speed up development and fund the trials, the U.S. has set up Operation Warp Speed, a partnership with the Department of Health and Human Services, the FDA and other federal agencies. Its goal is to deliver 300 million doses of a safe, effective vaccine by January 2021.   

These companies are included in the program: AstraZeneca, Janssen (Johnson & Johnson), Moderna, Novavax, Pfizer and Sanofi/GSK.

The FDA says that for any vaccine to be approved, it will need to prevent infection or decrease its severity in at least 50% of the people vaccinated. The goal, as with any vaccination, is to inoculate enough people with a vaccine that immunity spreads through a community, even if not everyone gets the vaccine. It’s called “herd immunity.” For this coronavirus, some experts say about 60% to 70% of the population would need to develop antibodies, whether from a vaccine or getting and recovering from COVID-19, to create herd immunity.

In other words, if not enough people get vaccinated once one or several are approved, it may prove difficult to reach herd immunity.

But, first, vaccine manufacturers must also show that it’s safe.

The FDA also said it could issue an emergency use authorization (EUA) for a COVID-19 vaccine, but that it would be decided on a case-by-case basis.


Which Vaccines Are in Phase III Trials?

Phase III trials confirm and expand on safety and effectiveness results from earlier trials. As of Aug. 5, these COVID vaccines are in Phase III:   

AstraZeneca & University of Oxford. University of Oxford scientists are partnering with AstraZeneca to develop a COVID-19 vaccine made from a weakened version of a common cold virus, the adenovirus, taken from chimpanzees. The adenovirus is genetically altered so it can’t reproduce itself. The vaccine is combined with genes of the spike protein to trigger production of  antibodies against it, which allows the immune system to destroy the SARS-CoV-2 virus.

Phase III trials are underway in Brazil and South Africa. In late July, researchers reported results up to day 56 of an ongoing phase I/II trial. About half of the more than 1,000 healthy adults tested got the vaccine and half got the meningitis vaccine as a comparison. The vaccine triggered antibody responses in T cells – another part of the immune system. One dose resulted in a 4-fold increase in antibodies in 95% of participants a month after vaccination and a T-cell response was maintained at the 2-month mark. Two doses produced the strongest immune response. No serious side effects were reported.

AstraZeneca has agreed to supply more than 2 billion doses globally, anticipating delivery of 400 million doses before the end of 2020.

BioNtech, Pfizer & Fosun Pharma. The companies are testing four vaccines, each using messenger RNA in different combinations to targeted antigens (to produce antibodies).  Called BNT162b2, the vaccine is being tested in phase II/III trials which launched July 27 in the U.S., and is expected to include up to 30,000 participants ages 18 to 85 at about 120 sites globally. 

Early results from  the ongoing phase I/II study of the BNT162b1 form of the vaccine showed it “elicited a robust immune response” in all adults tested who received it. The study tested three different doses against a placebo. Those getting the lower 2 of the 3 doses got a second injection on day 21. The middle dose and highest dose produced about the same immune response. Those in the highest dose group reported more side effects, so they weren't given a second dose.  Side effects were generally mild to moderate, including fatigue, headache, fever, sleep problems and pain at the injection site.   

Pfizer says it expects to produce  millions of vaccine doses in 2020, increasing to hundreds of millions in 2021. The U.S. government placed an initial order for 100 million doses, paying $1.95 billion, and can acquire up to 500 million additional doses. BioNTech has an agreement with Chinese drug maker Fosun Pharma to help in the vaccine development. 

Moderna. Moderna, in partnership with the National Institutes of Health, launched a phase III trial of its vaccine on July 27, expecting to enroll 30,000 adult volunteers. Earlier in July, Moderna announced that every person who received its vaccine, mRNA-1273, developed an immune response to the virus. Researchers also reported some side effects in the 45 people in the phase I study, but no significant safety issues. Enrollment in the phase II study was completed July 8 and the trial is progressing.

Moderna's vaccine uses messenger RNA, also called mRNA. It carries the instruction for making the spike protein, a key protein on the surface of the virus that allows it to enter cells when a person is infected. After it’s injected, it goes to the immune cells and instructs them to make copies of the spike protein, acting as if the cells have been infected with the actual coronavirus. This allows other immune cells to develop immunity.

Johnson & Johnson. J&J has launched a phase III trial of its vaccine, JNJ-78436735, developed by its Janssen Pharmaceutical Companies. The vaccine combines genes from the coronavirus with a modified adenovirus. The company plans to evaluate how well a single dose of the vaccine works, along with its safety, compared to placebo. The trial will test up to 60,000 adults 18 years and older, including people over age 60. Participants will be from the U.S. and 7 other countries. 

Sinopharm.  In mid-July, Sinopharm started a phase III clinical trial in the United Arab Emirates. The study will assess two forms of the vaccine in 15,000 volunteers, ages 18-60, for 3 to 6 months. The vaccine, from the Sinopharm Wuhan Biological Products Research Institute in China, was tested previously in 1,120 people ages 18-59 in phase I/II clinical trials and produced a strong neutralizing antibody response of 97.6% to 100%, depending on the timing and dosing of the injections. The vaccine uses an inactivated version of the virus.    

Sinovac Biotech. Sinovac Biotech's vaccine, CoronaVac, uses an inactivated version of the virus. Sinovac has partnered with Instituto Butantan in Brazil to launch a phase III trial.  Early results of a Phase II clinical trial released in June show that the vaccine induced antibodies to neutralize the virus after 14 days in 90% of people who received it. The vaccine requires two injections, given 2 weeks apart, according to the company.  No serious side effects have been reported in either phase I or II trials, which included 743 healthy volunteers. Sinovac Biotech, based in Beijing, said it  will develop the vaccine for global use.  

Other Contenders

Inovio. Inovio's vaccine, INO-4800, is a DNA vaccine in phase I clinical trials, with 40 volunteers. The technology uses DNA designed to produce a specific immune response. A handheld smart device uses a brief electrical pulse to open small pores in the skin to deliver the vaccine. Once the DNA is inside a cell, it instructs it to make many copies of the artificial DNA, which stimulates the body's natural immune response.

The company announced positive early  phase I data, finding that 94% of the 40 phase I volunteers had overall immune responses at week 6 after two doses of the vaccine. Human trials are also expected to begin this summer in China and South Korea. Multiple partners and collaborators are involved, including the Bill & Melinda Gates Foundation, the National Institutes of Health, and others.

Merck. Merck is partnering with the International AIDS Vaccine initiative (IAVI) and an Australian company it acquired to develop a COVID-19 vaccine.

Novavax. The company said results from the phase I part of a phase I/II trial show that Novavax's vaccine, NVX-CoV2373, is well-tolerated and triggered strong antibody responses in the 131 healthy adults tested. The most common side effects were tenderness and pain. All volunteers developed antibodies after a single dose and all developed neutralizing antibodies (which decrease the strength of the virus)  after the second dose.  The vaccine developed by the U.S.-based company uses technology that generates antigens (that stimulate the immune system) derived from the coronavirus spike protein. It’s testing two different doses of the two-dose regimen. One includes an adjuvant designed to boost the immune response.

Sanofi-GlaxoSmithKline.  Sanofi and GlaxoSmith Kline were added to the Operation Warp Speed list July 31.  Its vaccine candidate is based on technology used by Sanofi to produce a  flu vaccine. According to GSK, phase I/II trials are expected to begin in September. 

Volunteering for a Vaccine Trial

If you're interested in volunteering for a COVID-19 vaccine trial, here are some sources of more information: 

Government sponsored sites:

COVID-19 Prevention Network (CoVPN): This is funded by the National Institute of Allergy and Infectious Diseases and coordinated by the Fred Hutchinson Cancer Research Center in Seattle. Its goal is to enroll thousands of volunteers into COVID vaccine trials nationwide. Many research centers are using this site to find volunteers.

Clinicaltrials.gov: This is a government data base of public and private clinical studies done worldwide. The site also offers considerations for joining a clinical trial.

Sites that link volunteers with trials nationwide include:



World Without COVID

Individual hospitals, universities, research centers and others may also provide opportunities to enroll in a COVID-19 vaccine clinical trial. Some include:

Alliance for Multispecialty Research

Kaiser Permanente

Medical University of South Carolina

Meridian Clinical Research

Penn Medicine

Saint Louis University

SAResearch (Clinical Trials of Texas)

University of California Davis

University of California San Diego

University of Maryland

University of Rochester Medical Center

Vanderbilt University

Wake Research

You can also call or visit the website of your local hospital or research institution to find out if they are taking part in any trials.

WebMD Health News Reviewed by Hansa D. Bhargava, MD on August 07, 2020


Johnson & Johnson reaches deal with U.S. for 100 million doses of coronavirus vaccine at more than $1 billion."

Milken Institute,  Faster Cures Covid-19 Treatment and Vaccine Tracker.

U.S. Health & Human Services Fact Sheet: "Explaining Operation Warp Speed," June 16, 2020.

News release, AstraZeneca, "COVID-19 vaccine AZD1222 showed robust immune responses in all participants in Phase I/II trial," July 20, 2020 . 

The Lancet: "Safety and immunogenicity of the ChAdOx1 nCoV-19 vaccine against SARS-CoV-2: a preliminary report of a phase ½, single-blind, randomized controlled trial."

News release, Pfizer, "Pfizer and BioNTech Choose Lead MRNA Vaccine Candidate," "Pfizer and BioNTech announce agreement with U.S. government."

News release, Moderna, "Moderna Announces Phase 3 COVE Study of mRNA Vaccine Against COVID-19 (mRNA-1273) Begins."

News release, FDA, "Inovio's Vaccine Candidate Shows Promise in Early Trial."

News release, Johnson & Johnson, "Johnson & Johnson Announce Acceleration of its COVID-19 Vaccine Candidate; Phase 1-2a Clinical Trial to Begin in Second Half of July." 

News release, Merck: "How We are Responding to the Global Pandemic of COVID-19."

News release, Novavax: "Novavax Announced Positive Phase 1 Data for its COVID-19 Vaccine Candidate;" "Novavax Announces $1.6 Billion Funding From Operation Warp Speed."

News release, GlaxoSmithKline: "Sanofi and GSK Selected for Operation Warp Speed to Supply United States Government With 100 Million Doses of COVID-19 Vaccine."  

MD Anderson Center, “COVID-19 herd immunity: 7 questions, answered”

Nature: "Phase 1 / 2 study of COVID-19 RNA vaccine BNT162b1 in adults."

COVID-19 Prevention Network.


News release, Johnson & Johnson: "Johnson & Johnson Initiates Pivotal Global Phase 3 Clinical Trial of Janssen's COVID-19 Vaccine Candidate." 


© 2020 WebMD, LLC. All rights reserved.