Go big or go home: That's the attitude that many Robinhood investors seem to have.

The list of the 100 most popular stocks on the trading platform includes quite a few stocks that could be huge winners -- or huge losers.

This kind of high-risk/high-reward proposition won't appeal to every investor. But if you have a really aggressive approach to investing, here are three ultra-risky Robinhood stocks that just might make you a fortune.

Hands holding blocks spelling "risk" and "reward."

Image source: Getty Images.

iBio

In August, iBio (NYSEMKT:IBIO) announced encouraging preclinical results for experimental COVID-19 vaccine IBIO-201. Those results showed that IBIO-201 generated a robust immune response in mice. 

iBio has also tested another experimental COVID-19 vaccine, IBIO-200, in preclinical trials. However, in September the biotech selected IBIO-201 as its candidate to advance into toxicology studies. If all goes well with those studies, the company hopes to move forward with clinical-stage testing of the vaccine in humans. 

In addition, iBio licensed a COVID-19 therapeutic candidate, ACE2-Fc, from Planet Biotechnology. The biotech's only clinical-stage pipeline candidate right now is IBIO-400, an experimental swine fever vaccine for animals.

It's still very early for all of iBio's programs. If the company's COVID-19 vaccine and/or its therapeutic candidate go on to deliver great results in clinical testing, though, the biotech stock could soar a lot higher than its year-to-date gain of more than 580%.

Inovio Pharmaceuticals

Inovio Pharmaceuticals (NASDAQ:INO) could be a lot closer to success with its coronavirus vaccine candidate, INO-4800. The company had hoped to begin a phase 2/3 clinical study of the experimental vaccine in September. However, the Food and Drug Administration placed the study on partial clinical hold because it had questions about the trial.

It's now a waiting game for Inovio. The biotech responded to the FDA's questions and could find out within the next few weeks if it can move forward with the planned phase 2/3 study of INO-4800. A positive decision by the FDA would almost certainly send Inovio's shares into orbit.

Inovio's pipeline has plenty of other potential winners. VGX-3100 stands at the top of the list. The company is evaluating the experimental drug in a late-stage study targeting precancerous cervical dysplasia caused by human papillomavirus (HPV). Inovio expects to report results from this study in the first half of 2021.

The biotech also is evaluating VGX-3100 in phase 2 studies for potentially treating HPV-related anal and vulvar dysplasia. Its pipeline also includes 10 other programs. 

Sorrento Therapeutics

You'll be hard-pressed to find a company with more irons in the COVID-19 fire than Sorrento Therapeutics (NASDAQ:SRNE). The biotech is working on tests, treatments, and vaccines targeting the coronavirus.

Sorrento's lead pipeline candidate, abivertinib, is currently in phase 2 testing for potential treatment of severe cases of COVID-19. The immunotherapy also being evaluated in a pivotal late-stage study targeting non-small cell lung cancer.

The biotech hopes to win FDA emergency use authorization for a COVID-19 antibody test and diagnostics test. It's advanced one experimental antibody therapy targeting COVID-19 into an early stage study and has filed for FDA approval to advance two other antibody therapies into clinical testing. Sorrento also has a coronavirus vaccine candidate, STI-3333.

In addition to its COVID-19 programs, Sorrento's pipeline includes several clincal-stage candidates targeting cancer and pain. Although its shares have nearly doubled so far this year, success with any of its clinical programs would likely provide a big catalyst for Sorrento.

Putting the ultra in ultra-risky

Any or all of these three popular Robinhood stocks could easily generate tremendous returns, perhaps even before the end of 2020. However, iBio, Inovio, and Sorrento are ultra-risky for a reason: Their prospects hinge on clinical results that might not turn out well.

The biotech stocks might make investors a fortune, but they could just as easily be disastrous. The possibility of going big comes joined at the hip with the potential to go home with empty pockets.