CureVac Started the Day Worth More Than Novavax. Then Its Vaccine News Hit.

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CureVac’s vaccine was 47% effective at preventing Covid-19 symptoms in a trial of 40,000 volunteers.


Shares of vaccine start-up


lost half their value in Wednesday’s after-hours trading following the German company’s announcement that the preliminary data from its Covid-19 study are disappointing. In a pivotal trial among 40,000 volunteers, the shots were 47% effective at preventing Covid symptoms. That missed the study’s preset measure for success.

The stock (ticker: CVAC) closed Wednesday trading down 3.5%, at $94.79. Then came the news. That has taken nearly 50% off the price in after-hours trading, to drop it to $48.80. “While we were hoping for a stronger interim outcome, we recognize that demonstrating high efficacy in this unprecedented broad diversity of variants is challenging,” said CureVac chief executive Dr. Franz-Werner Haas. The study will continue to count Covid cases in the group, he said, and the final data may change the efficacy rate. The company will hold a conference call Thursday morning.

CureVac’s showing comes on the heels of more impressive results from


(NVAX), which reported Monday that its vaccine was more than 90% effective at preventing Covid in a 30,000-person trial. Novavax shares followed that good news by selling off from a Monday height of $217 to a Wednesday close of $176. In Wednesday’s after hours, Novavax shares were up 2.5%, to $180.70.

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Unexpected delays in CureVac’s study results had raised concerns earlier this month. The technology used in CureVac’s shots is the same messenger-RNA approach that delivered roughly 95% efficacy for the vaccines of


(MRNA) and for the team of


(PFE) and


(BNTX). Perhaps that’s why investors were giving CureVac an $18 billion market cap at Wednesday’s close, compared with $13 billion for Novavax, which uses a more traditional, if time-tested, technology in its vaccine. Those valuations will surely change when trading begins on Thursday now that Novavax seems alone as a high-efficacy alternative to the Moderna and Pfizer vaccines.

Moderna stock slid this week from $218 to $198 as Novavax proved itself a potential rival. After CureVac’s announcement, Moderna shares edged up 1% in after-hours trading to $199.96. BioNTech stock was up 1% after the close, following its three-day drop from $239 to $203.89. Less affected by vaccine developments, shares of the drug giant Pfizer were flat.

CureVac cited new variants of the virus for its vaccine’s disappointing performance. With backing from


(BAYRY), it conducted the study in 10 countries around Europe and Latin America. Among the study’s Covid cases in which the virus was genetically sequenced, only one case was caused by the original SARS-CoV-2 strain, said CureVac, while 57% were caused by the concerning new variants. Novavax also encountered the so-called variants of concern in its trial, but its shot performed better against them.

CureVac says it will continue developing improved vaccines in a collaboration with


(GSK), adding that they hope to start clinical trials of the next-generation mRNA shots in this year’s third quarter.

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