Coronavirus vaccines have been making headlines recently, but so far, they all remain merely candidates in various stages of development. Nearly 130 investigational vaccines are in preclinical studies, while 18 have entered testing in humans, according to the World Health Organization.

So if you're hoping to get a vaccine to protect yourself from contracting COVID-19, the illness caused by the novel coronavirus, you'll have to wait until at least one candidate completes late-stage trials and the U.S. Food and Drug Administration gives its maker the official nod to move forward with commercialization.

A person wearing a stethoscope and mask vaccinates a masked patient or volunteer.

Image source: Getty Images.

Which companies are leading the coronavirus vaccine race?

A number of biotech and pharmaceutical companies are racing to develop an effective COVID-19 vaccine. Moderna (NASDAQ:MRNA), AstraZeneca (NYSE:AZN), Inovio Pharmaceuticals (NASDAQ:INO), Novavax (NASDAQ:NVAX), and Johnson & Johnson (NYSE:JNJ) are among the leaders. Here are a few details about their respective programs.

Moderna

Moderna's phase 1 and 2 trials are ongoing, and the company plans to begin a phase 3 study on as many as 30,000 participants this month. Moderna reported positive interim phase 1 data, saying participants produced binding and neutralizing antibodies at levels seen in recovered COVID-19 patients or above. Binding antibodies signal a pathogen to the immune system, but more importantly, neutralizing antibodies actually block infection. Neutralizing antibody results were only available for eight participants, so Moderna will have to show this trend in a much larger population as trials continue.

Moderna's data also applied to a younger patient group -- ages 18 to 55. In the coming weeks, Moderna must demonstrate the safety and efficacy of its vaccine in older patients. This is particularly significant because elderly people have been most vulnerable during the coronavirus pandemic. Moderna's vaccine uses messenger RNA to instruct the body's cells to produce proteins to protect against infection.

AstraZeneca

Moderna was the first to enter human trials with a vaccine candidate, but AstraZeneca recently slipped into the lead. AstraZeneca partnered with the University of Oxford this spring, and they're now testing their candidate in a phase 2/3 trial. This trial will enroll more than 10,000 people in the U.K., with the phase 2 part broadening to include a small number of volunteers in age groups five to 12, 56 to 69, and over 70. The phase 3 part of the study will examine the vaccine's efficacy in a large group of participants over age 18. Researchers also are conducting a phase 3 trial in Brazil.

AstraZeneca's vaccine candidate is made from a weakened adenovirus, from one of the virus families that can cause the common cold, and includes genetic material from COVID-19 that will help the body identify the pathogen and defend itself against infection. Researchers haven't yet released study data.

Inovio

Clinical-stage biotech Inovio recently announced positive phase 1 data for its COVID-19 vaccine. The company said 94% of the 36 participants age 18 to 50 demonstrated immune responses six weeks after two doses. Inovio said this was based on binding and neutralizing antibodies and T-cell immune responses, but the report didn't offer further details. The company plans to begin a phase 2/3 efficacy study this summer.

The Inovio vaccine is based on the company's DNA medicines technology. Inovio's Cellectra device injects circles of DNA called DNA plasmids into the body. Those plasmids have been reorganized to produce immune response.

Novavax

In late May, Novavax announced the enrollment of the first volunteers in the phase 1/2 trial of its vaccine candidate. Like AstraZeneca, the company chose a trial design that combines phases, to help advance the vaccine more quickly. The first part is enrolling 130 participants age 18 to 59 in Australia. The second part, in various countries including the U.S., will expand the age range.

Initial immune response and safety results are expected this month.

Johnson & Johnson

The big pharma company initially planned to begin testing its vaccine in humans this fall, but changed its plans, based on promising preclinical data. J&J now aims to begin a phase 1/2a trial later this month. This study will involve more than 1,000 volunteers age 18 through 55, as well as adults age 65 and older.

If all goes well with that study, J&J and the National Institute of Allergy and Infectious Diseases are discussing the possibility of starting a phase 3 trial earlier than planned as well.

When will a coronavirus vaccine be available?

The U.S. government aims to get a vaccine to the public by January with its program called Operation Warp Speed. As part of Operation Warp Speed, the Department of Health and Human Services offered as much as $483 million in support to Moderna, $1.2 billion to AstraZeneca, and $456 million to Johnson & Johnson.

Moderna says it's on target to deliver about 500 million doses per year, and possibly as many as 1 billion, by next year. Oxford researchers, referring to the AstraZeneca vaccine, said they'd have efficacy results from their phase 3 trial this fall in "the best-case scenario."

For all companies investigating vaccines, trial results will determine the final timeline. If all goes well, it's possible one or more companies may meet the government's goal. However, any headwinds could slow the process.

Could more than one company win the coronavirus vaccine race?

The biggest stock gain may go to the first company to cross the finish line, but that doesn't mean the game is over for all the other players. Considering the global need for a vaccine, there is room for more than one vaccine maker. And in the long run, the company with the best vaccine -- whether it's the first to market or not -- is likely to take market share.

In the meantime, as companies move closer to the final research stage, investors will keep a close eye on each bit of news. And this news is likely to be a catalyst for shares of these biotech and pharmaceutical companies in the coming months.