Covid-Tied Biotechs Unwind Gains After Pfizer Vaccine Data

(Bloomberg) -- Biotech companies that are chasing treatments and vaccines for Covid-19 tumbled Monday after positive news about Pfizer Inc.’s inoculation.

Smaller vaccine developers such as NantKwest Inc. and Inovio Pharmaceuticals Inc. fell after study results from Covid-19 shots from Pfizer and its German partner BioNTech SE showed that they could prevent more than 90% of infections. Many of these smaller drug developers have yet to develop a successful treatment of any kind and have seen triple or even quadruple digit share gains so far this year.

NantKwest slumped as much as 16%. Inovio sank as much as 22%. The company’s Phase 2-3 vaccine study was put on a partial hold in September. Humanigen Inc., which is developing a treatment for a potentially lethal side-effect of the virus, tanked 33%. Sorrento Therapeutics Inc., which has been touting results for its antiviral treatment in hamsters, fell 17%.

Vaxart Inc., which is testing an oral vaccine, tumbled as much as 27%. Arcturus Therapeutics Holdings plunged 48% after revealing a first look at its single-shot vaccine, which missed some investor’s expectations. Even high-profile partnerships didn’t stop the bleeding. GlaxoSmithKline Plc-partnered Vir Biotechnology Inc. dropped by 21%. Glaxo and Vir are expected to report late-stage results for their Covid antibody treatment in the first quarter.

Moderna Inc., which, like Pfizer, is working on messenger-RNA vaccines and expected to have interim results imminently, rallied 11% on the heels of Pfizer’s success. Novavax Inc., which is expected to start a late stage-study later this month, briefly dropped 11% premarket Monday, then rallied as much as 13% after revealing its vaccine received fast-track status in the U.S. It is now up less than 2%.

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