What happened

Shares of Heat Biologics (HTBX 0.95%) popped on Thursday after the biopharmaceutical company shared promising preclinical data for its COVID-19 vaccine. As of 1:30 p.m. EDT, Heat Biologics' stock was up 15% after rising as much as 23% earlier in the day. 

So what

Heat Biologics said data generated at the University of Miami Miller School of Medicine showed a "robust T cell driven immune response" to SARS-CoV-2, the virus that causes COVID-19. The biotech company said its experimental vaccine induced the expansion of CD8+ T cells that kill virus-infected cells, as well as CD4+ T cells that help to produce antibodies. Better still, the T cells released cytokines that boosted the anti-viral immune response, which Heat Biologics believes could play an important role in protecting against respiratory viruses.

"Specifically, we noted several important immune responses generated by the vaccine against SARS-CoV-2 after a single injection, including SARS-CoV-2 specific CD8+ and CD4+ T cells in the lungs and airways," University of Miami Professor Natasa Strbo said in a press release.

People are working in a laboratory.

Heat Biologics stock rose sharply on positive coronavirus vaccine data. Image source: Getty Images.

Now what

Heat Biologics CEO Jeff Wolf believes this robust T cell activity could set its vaccine candidate apart from others, while also potentially allowing it to be used alongside them. "Unlike most of these approaches that drive primarily an antibody response, our COVID-19 vaccine is designed to drive predominantly T cell immunity along with antibody responses and innate immunity," Wolf said in a press release. "As a result, we believe our vaccine has the potential to be used as either a stand-alone vaccine, or in combination with these other approaches to enhance efficacy."

Heat Biologics said it will publish the full details of its study in the coming weeks.