When will a COVID-19 vaccine be available? How effective will it be? Those are two of the most pressing questions being asked by many with the number of COVID-19 cases rising in much of the U.S.
Unfortunately, the questions can't be answered yet with a high level of confidence. But there are 23 COVID-19 vaccine candidates currently in clinical testing, according to the World Health Organization (WHO). The progress of these candidates can at least provide a clue as to when a COVID-19 vaccine might be available. Here are those vaccine candidates and how likely they could be to win regulatory approval.
Image source: Getty Images.
In phase 1 testing
The field of early stage COVID-19 vaccine candidates is crowded. Of the 23 COVID-19 vaccine candidates currently in clinical testing, 18 are in phase 1 studies:
| Organization(s) |
Vaccine Candidate |
Status |
|---|---|---|
| AnGes / Takara Bio / Osaka University | DNA vaccine | In phase 1/2 study. |
| BioNTech (BNTX +0.69%) / Pfizer (PFE +1.25%) |
BNT162 (Four candidates) | In phase 1/2 study. |
| Bharat Biotech | Whole-virion inactivated vaccine | In phase 1/2 study. |
| Cadila Healthcare | ZyCoV-D | In phase 1/2 study. |
| Clover Pharmaceuticals / GlaxoSmithKline / Dynavax | SCB-2019 | In phase 1/2 study. |
| CSL / Sequirus / University of Queensland | Molecular clamp stabilized spike protein with MF59 adjuvant | In phase 1/2 study. |
| CureVac | CVnCoV | In phase 1/2 study. |
| Genexine Consortium | GX-19 | In phase 1/2 study. |
| Gamaleya Research Institute | Gam-COVID-Vac | In phase 1/2 study. |
| Imperial College London | RNA vaccine | In phase 1/2 study. |
| Inovio Pharmaceuticals | INO-4800 | In phase 1/2 study. |
| Novavax (NVAX +2.31%) | NVX‑CoV2373 | In phase 1/2 study. |
| Institute of Medical Biology / Chinese Academy of Medical Sciences | Inactivated SARS-CoV-2 vaccine | In phase 1/2 study. |
| Medicago / GlaxoSmithKline / Dynavax | Plant-derived virus-like particle | In phase 1/2 study. |
| Sinopharm / Beijing Institute of Biological Products | Inactivated SARS-CoV-2 vaccine | In phase 1/2 study. |
| Sinopharm / Wuhan Institute of Biological Products | Inactivated SARS-CoV-2 vaccine | In phase 1/2 study. |
| Vaxine Pty Ltd / Medy-Tox | COVAX-19 | In phase 1/2 study. |
| Walvax Biotechnology / People's Liberation Army Academy of Military Sciences | ARCoV | In phase 1/2 study. |
Data sources: WHO, ClinicalTrials.gov, company press releases.
BioNTech and Pfizer reported positive results on July 1 for BNT162b1, one of four candidates in development. The FDA recently granted Fast Track designation to two of those candidates, which paves the way for an expedited review process.
Novavax has attracted a lot of attention for its COVID-19 vaccine candidate as well. Operation Warp Speed, the U.S. government's program to accelerate COVID-19 vaccine development, selected NVX-CoV2373 to receive $1.6 billion in funding.
What are the chances of FDA approval for a vaccine candidate in phase 1 testing? Very low, at least based on historical data. Only 16% of experimental vaccines in early stage studies between 2006 and 2015 ultimately won FDA approval, based on an analysis conducted by biopharmaceutical industry trade organization BIO.
In phase 2 testing
Two Chinese drugmakers are currently evaluating COVID-19 vaccine candidates in phase 2 clinical studies:
| Organization(s) |
Vaccine Candidate |
Status |
|---|---|---|
| Cansino Biologics / Beijing Institute of Biotechnology | Ad5-nCoV | In phase 2 study |
| Anhui Zhifei Longcom Biopharmaceutical / Institute of Microbiology, Chinese Academy of Sciences | Adjuvanted recombinant protein | In phase 2 study |
Data sources: WHO, ClinicalTrials.gov, Chinese Clinical Trial Registry, company press releases.
The Chinese military is already using Cansino's experimental Ad5-nCoV vaccine under a one-year special permission granted by China's Central Military Commission. The vaccine candidate isn't approved for use outside of military personnel at this time, though.
Neither of these two COVID-19 vaccine candidates is being tested in the U.S. at this point. The odds an experimental vaccine in a phase 2 clinical trial will eventually win FDA approval is low, based on BIO's historical data -- less than 25%.
In phase 3 testing (or soon will be)
There are three leaders in the COVID-19 vaccine race based on the clinical progression of their respective candidates. Each of these companies' COVID-19 vaccine candidates is either in phase 3 clinical studies or soon will be.
| Organization(s) |
Vaccine Candidate |
Status |
|---|---|---|
| AstraZeneca (AZN +0.00%) / University of Oxford | AZD1222 | In phase 2/3 study |
| Moderna (MRNA 1.76%) asdf | mRNA-1273 | Phase 3 study scheduled to begin on July 27, 2020 |
| Sinovac Biotech | CoronaVac | Phase 3 study scheduled to begin in July 2020 |
Data sources: WHO, ClinicalTrials.gov, company press releases.
Moderna's COVID-19 vaccine program has received the most publicity in the U.S. The biotech recently announced the publication of results from a phase 1 study of mRNA-1273 in The New England Journal of Medicine. Those results showed that Moderna's COVID-19 vaccine candidate produced neutralizing antibodies (which can prevent viral infection) in all 45 participants in the study.
It's not surprising that Moderna ranks as a big winner among biotech stocks in 2020. So far this year, Moderna's shares are up well over 300%.
Chinese drugmaker Sinovac reported in June that its COVID-19 vaccine candidate CoronaVac produced neutralizing antibodies in over 90% of patients in a phase 1/2 clinical study. Results from a phase 1 study of AZD1222, the COVID-19 vaccine candidate being developed by AstraZeneca and the University of Oxford, are expected to be published on July 20 in The Lancet medical journal.
It's still too soon to know whether any of these vaccine candidates will be successful in late-stage testing. However, 74% of experimental vaccines that made it to phase 3 clinical trials between 2006 and 2015 went on to win FDA approval, according to BIO.
