CureVac's corona vaccine candidate CVnCoV missed the statistical targets in a second interim analysis.
The Tübingen-based company announced this in a mandatory announcement on Thursday night.
"In a previously unprecedented environment with at least 13 variants within the subset of study participants examined in this interim analysis, CVnCoV achieved a preliminary effectiveness of 47 percent against COVID-19 disease of any severity and thus did not meet the specified statistical success criteria." traded CureVac shares collapsed in after-hours trading by almost 40 percent.
Initial analyzes have shown that the effectiveness depends on the age group examined and the strain of the virus, it said.
The Data Safety Monitoring Board (DSMB) has confirmed a good safety profile and the study will continue until the final analysis.
The first-generation vaccine candidate is in the final stages of clinical development. An initial interim analysis did not reveal any safety concerns. CureVac works with Bayer.