(Bloomberg) — The world’s top makers of Covid-19 vaccines are dropping after tests of Novavax Inc.’s shots showed they were 90% effective at preventing symptoms.

Stocks tied to inoculations already cleared for emergency use fell in Monday’s trading, led by Moderna Inc.’s slide of as much as 9.5%. Pfizer Inc. fell 1.6% and the drugmaker’s German partner BioNTech SE dropped 6.1%. Even the consumer giant Johnson & Johnson slipped 0.6%, slightly more than the S&P 500 index as the broader market dropped back from Friday’s record highs.

Novavax itself wasn’t immune from the downdraft it created, with the stock reversing a 9.5% gain on Monday to fall about 1%. The shot’s efficacy was better than Wall Street was expecting amid the spread of more resistant variants, and that’s raising the specter of new competition. Novavax now has “a viable alternative to mRNA vaccines,” like Pfizer and BioNTech or Moderna’s shots, an analyst at Jefferies said.

But with Novavax up 91% so far this year and after a more than 2,700% leap in 2020, it wasn’t enough to further bolster shares. Biotech stocks often climb ahead of highly watched catalyst, only to give back gains even after a positive update.

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