German vaccine manufacturer CureVac said Wednesday that interim data from tests at the late stage of its coronavirus outbreak show relatively low effectiveness in protecting people against COVID-19.
The results appear to be a significant return on CureVac’s efforts to develop a coronavirus vaccine, and the value of the company’s stock has fallen in business after hours.
Although not all data from its trial involving 40,000 participants in Latin America and Europe have been evaluated yet, the company said the intermediate results show that vaccination has an effectiveness of 47% against COVID-19 disease of any severity.
This did not meet what the company said were its “pre-specified statistical success criteria,” although it did not state what they were.
The World Health Organization has stated that vaccines with an effectiveness of more than 50% are worth using, although many of those already approved have a much higher rate.
CureVac said the study was hampered by the wide range of variants found among the reviewed COVID-19 cases in the trial and that the final results may also change.
“While we expect a stronger interim result, we recognize that demonstrating high efficiency in this wide variety of unprecedented variants is challenging,” its chief executive, Franz-Werner Haas, was quoted as saying.
Haas said CureVac will continue to work on a final analysis and “the overall effectiveness of the vaccine may change.”
The company said it has sent the data to the European Medicines Agency, which conducts a rotating review of the vaccine.
“The study will continue until the final analysis and the totality of the data will be assessed by the most appropriate regulatory route,” CureVac said.
External experts have called the data down to disappointing, but have been careful to compare it directly with other hits already authorized for use.
Deborah Fuller, a professor of microbiology and vaccine specialist at the University of Washington School of Medicine, said CureVac treated “a fairly different environment” from some of its rivals who had tested their blows when the original variant was still in use. dominant.
The CureVac trials took place in 10 different countries, he noted: “The more countries in which you try, the more variants you have to compete.”
Another problem could be the mRNA technology used in the CureVac strain, which is slightly different from that used in the BioNTech-Pfizer and Modern vaccines, said Mark Slifka, a professor of microbiology and immunology at Oregon Health and Science University.
CureVac uses unmodified mRNA, which can activate a different immune response in the body that affects effectiveness, he said.
“It could be variants, it could be the type of mRNA, or it could be a combination of all of the above,” Slifka said.
Haas, the chief executive, said the large number of variants CureVac encountered in its trial – with only a single case of COVID-19 attributable to the original variant – “underscores the importance of developing next-generation vaccines instead.” that new virus variants continue to emerge. “