Inovio's 860% year-to-date rally takes a breather after the release of Phase I data for company's COVID-19 vaccine candidate

• Inovio has rallied 860% year-to-date as investors bid up the company's stock in hopes of the successful development of a vaccine for COVID-19.
• On Tuesday, Inovio fell as much as 17.8% after the company released early Phase I data on its INO-4800 COVID-19 vaccine.
• The company said 94% of Phase I participants demonstrated an immune response to the vaccine candidate.
• Inovio said its vaccine candidate was selected to participate in a non-human primate study as part of the US government's Operation Warp Speed.
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Inovio's Tuesday morning release of early-stage data on its COVID-19 vaccine candidate sent shares lower by as much as 17.8%, giving the stock a breather after it rallied 860% year-to-date as of Monday's close.

Investors have bid up the company on hopes that its vaccine candidate for COVID-19 proves successful in human trials.

The interim Phase 1 data from Inovio showed that 94% of trial participants demonstrated overall immune response at week six after two doses of INO-4800, according to the company.

Inovio said it plans to add older participants to its vaccine trial and to initiate a Phase 2/3 efficacy trial for INO-4800 later this summer, upon regulatory concurrence.

Investors might be selling shares today due to a lack of information from the company.

In a note published on Tuesday morning, Stifel said, "we believe this preliminary data is likely to raise more questions (vs. answers) on the competitive immunogenicity front and limits our ability to get more-constructive on INO shares based on this limited disclosure alone."

Stifel downgraded shares of Inovio to Hold on June 26.

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Inovio also said its vaccine candidate was selected to participate in a non-human primate challenge study as part of the US government's Operation Warp Speed. Vaxart is another company working on a vaccine for COVID-19 that was selected to participate in the same challenge study, which sent its stock soaring.

Operation Warp Speed is a private-public partnership by the federal government designed to speed up the development and production of a COVID-19 vaccine, therapeutics, and related diagnostics. Companies selected by the government to participate and receive funding include Merck, Moderna, Pfizer, Johnson & Johnson, and AstraZeneca.