Shares of Inovio Pharmaceuticals Inc. gained 8.0% in premarket trading on Monday after the company said its experimental COVID-19 vaccine was safe and also triggered antibody titers in 400 or so adult participants in a Phase 2 clinical trial. The results were published Friday as a preprint. Inovio has largely struggled to move its two-dose, DNA-based COVID-19 vaccine candidate forward. A Phase 3 clinical study is still on hold, due to “remaining questions” from the Food and Drug Administration about a device used for administering the shots. Inovio said in April that the Department of Defense stopped funding development of its COVID-19 vaccine, and the Phase 3 clinical trial for the still-investigational shots will largely be conducted outside of the U.S. Inovio’s stock is down 22.6% for the year, while the S&P 500 is up 12.7%.

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