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CureVac plunges after COVID-19 vaccine falls short on efficacy

The Curevac company headquarters in Tuebingen, Germany.Sebastian Gollnow/Associated Press

CureVac NV lost more than half its value after a preliminary analysis of a large study found its Covid-19 vaccine fell short of the high efficacy bar set by other messenger RNA shots.

The shares plunged more than 52 percent in German trading, wiping out almost $9.6 billion in market value, after the company said the vaccine was only 47 percent effective in an early trial analysis.

The findings throw the future of the vaccine into question as wealthy nations around the world move swiftly to inoculate their populations with shots already available. The spread of virus variants muddied CureVac’s research, but other vaccines have shown they offer protection against those as well.


“This could cast doubt on the competitiveness of its mRNA platform,” said Eun K. Yang, an analyst at Jefferies. He called the results “quite disappointing” and cut his price target for the company to $45, down from $58 previously.

The stock trades primarily on the Nasdaq. The study data was released after the U.S. close Wednesday, and the shares dropped 44 percent in U.S. pre-market trading Thursday to below the price of the company’s initial public offering last August.

The interim analysis of data from about 40,000 volunteers included 134 Covid cases, the German company said in a statement. CureVac declined to say how many who got the shot got sick or how many received a placebo.

In April, Elon Musk tweeted about CureVac, which Tesla Inc. has partnered with on a vaccine printer, saying it “sounds like they’re a few months away from regulatory approval.” He added that “a tidal wave of vaccine is coming this summer.” He later deleted the tweet.

Like the shots from Moderna Inc. and the Pfizer-BioNtech alliance, CureVac’s vaccine relies on mRNA, enlisting the body’s own cells as vaccine factories. Unproven until last year, the technology has now catapulted to the forefront of the global fight against Covid.


CureVac’s shot, though, is subtly different from its competitors because it uses an unmodified form of mRNA. The company was also testing a lower dose of mRNA compared with Moderna’s and Pfizer’s.

The data comes as the world is at something of a crossroads in the Covid fight, with global infections falling even as outbreaks in places with less access to vaccines serve as a reminder that the pandemic is far from over. The wealthiest countries have taken an outsize share of the more than 2.4 billion shots administered so far.

CureVac’s product doesn’t require deep freezing, meaning it could be a boost in the developing world.

Partly owned by the German government, CureVac has forged partnerships with Bayer AG, GlaxoSmithKline Plc and the U.K. government aimed at speeding production of its shot and future versions that will target mutated strains.

More details will emerge in the final readout of the study, which will include more than 200 cases and could come within two or three weeks, CureVac said. The company plans to finish its trial and seek regulatory approval. “There is a huge need for vaccine, and I think we can still make a contribution,” Chief Executive Officer Franz-Werner Haas said.

The work with Glaxo on second-generation candidates continues, with the goal of introducing a vaccine next year. Those products “have a different, enhanced mRNA backbone” and early data suggests their ability to boost immunity could be much stronger, the U.K. drugmaker said in a statement.


The proliferation of variants in the CureVac trial is testimony to how the pandemic has changed since the first large vaccine clinical trials were run last year.

CureVac’s researchers genetically sequenced 124 of the 134 cases they included in their analysis. Just one of the sequenced cases was due to the original SARS-CoV-2 virus first identified in Wuhan, China. The rest came from a range of variants, including 21 percent of cases attributable to a new variant called lambda that was first identified in Peru.

The World Health Organization added lambda to its watchlist as a variant of interest on Monday.

Some 57 percent of the Covid cases in the study were due to so-called variants of concern, the four variants that the World Health Organization has deemed the most worrying. Most of these -- about 41 percent of all the cases -- were due to the alpha variant first observed in the U.K., CureVac said.

That variant is now the most common in the U.S., and other vaccines, including shots from Pfizer Inc. and BioNTech SE as well as Novavax Inc., have shown themselves effective against it. CureVac didn’t release detailed data about how its shot performed against each of the variants.

The company has said it plans to supply 300 million vaccine doses this year, enough to immunize 150 million people. Together with partners, it has said it will supply more than 1 billion doses in 2022.