Many companies that successfully developed effective coronavirus vaccines are reaping the benefits and generating millions -- sometimes billions -- in sales from their products. However, other players are still looking to get in the game.

Two notable companies still hoping to make a dent in this market include Inovio Pharmaceuticals (INO -6.14%) and Vaxart (VXRT -3.63%). Can these two latecomers still profit from their coronavirus-related efforts? Let's discuss whether it is worth it for investors to bet on these companies.

1. Inovio Pharmaceuticals

Once considered a leader in the hunt for a coronavirus vaccine, Inovio Pharmaceuticals ran into several regulatory headwinds. For instance, the company's phase 2/3 clinical trial for its candidate, INO-4800, was put on clinical hold by authorities in the U.S. Regulators had questions regarding Inovio's Cellectra 2000, a proprietary handheld device that looks like an electric toothbrush, and which the biotech uses to administer the vaccine.

Physician vaccinating patient.

Image source: Getty Images.

Inovio received the green light to run a late-stage clinical trial for INO-4800 in other countries. The company's ongoing phase 3 study, dubbed Innovate, includes participants from Brazil, India, the Philippines, Mexico, and Colombia. Inovio eventually received the green light from regulators in the U.S. to proceed with its Innovate. But more issues arose with this study.

Inovio Pharmaceuticals has paused enrollment in Innovate as it requests regulatory approval to change the study's primary endpoint from prevention of virologically confirmed COVID-19 disease to prevention of severe COVID-19 disease. The company's decision to seek this change came as a result of INO-4800 producing decreased levels of antibodies against the omicron variant of the coronavirus.

While Inovio originally planned to have interim results for Innovate during the first half of the year, that will no longer happen. And it isn't clear when the biotech will resume enrollment in the trial -- or when interim results will be ready. In other words, Inovio's hopes in this market look bleak. The company will have to produce excellent results for its candidate to make a dent in the market.

That won't happen for at least another year, at best. The biotech does have other candidates. Most notably, there is VGX-3100, a potential DNA vaccine for the treatment of HPV-associated cervical dysplasia (a precancerous condition). The company reported unimpressive results from a phase 3 study for VGX-3100 last year although another late-stage trial is being conducted.

Overall, there is too much uncertainty regarding Inovio Pharmaceuticals' leading candidates -- INO-4800 and VGX-3100 -- for the biotech to be worth considering right now, not to mention that the company is consistently unprofitable. In short, investors had better look elsewhere. 

2. Vaxart

Vaxart's coronavirus candidate hasn't even made it to a phase 3 study yet. It is currently undergoing a phase 2 clinical trial. But there are some reasons to be optimistic. Vaxart has a secret weapon: The biotech focuses on developing oral vaccines. Vaxart's coronavirus candidate is of the same variety.

There are some obvious advantages to Vaxart's approach. Pills are easier to handle than other types of vaccines. The former can be kept at room temperature, unlike some of the current leading vaccines that come with stringent and rigorous storage requirements. Vaxart does have another thing going its way. Its investigational vaccine seems to be able to produce antibodies in the nose and other mucosal sites where the infection happens, something other vaccines currently on the market are unable to do.

Vaxart's candidate still has a long way to go before earning regulatory approval despite these advantages. And, of course, there is no guarantee that it will go that far. The company could run into clinical and regulatory obstacles -- something those interested in the biotech industry always have to keep in mind. Also, Vaxart does not have any candidates in phase 3 studies. The company does not generate much revenue, and it is not profitable.

Vaxart's coronavirus project seems promising. And if it ends up earning the green light from regulators, the company's candidate could carve out a decent niche for itself. But Vaxart remains a high-risk, high-reward play at this stage. Only those comfortable with considerable volatility should consider initiating a (small) position in this biotech.