99% of participants retained very high neutralising antibody levels 12 months after treatment
Valneva has announced positive antibody persistence data twelve months for its chikungunya vaccine candidate, VLA1553. Results from the single-dose vaccination have emerged 12 months after the treatment was administered.
The report follows positive safety and immunogenicity data during a phase 3 study of the therapy in March 2022. Meanwhile, Valneva also set up a dedicated antibody persistence trial to monitor a subset of participants for a period of at least five years to confirm the long-term durability of the antibody response after a single vaccination.
The antibody persistence trial enrolled 363 healthy adult participants and monitored them from month six after the vaccination to month 12. During this period, 99% of participants retained neutralising antibody levels above the seroresponse threshold of 150, 12 months after the single-dose vaccination.
These levels confirm the antibody persistence profile observed in an earlier study. The antibody persistence was similar in older adults aged over 65, who retained neutralising antibody titres comparable to younger adults.
There were no safety concerns identified for the duration of the follow-up study, confirming the safety profile observed across previous studies.
Juan Carlos Jaramillo, chief medical officer at Valneva, reflected: “We are excited about the twelve-month data which is in line with what we saw from our previous read out at month six, and strengthen the possibilities of inducing a long-lasting antibody response with our chikungunya vaccine candidate.”
“We are looking forward to completing the [Biologics License Application] BLA rolling submission to the [US Food and Drug Administration] FDA and potentially to changing people’s lives. If our investigational vaccine is approved, we are confident that it can help address this major, growing and unmet public health threat,” he added.
Valneva expects to finalise its BLA submission with the FDA by the end of the year.
Chikungunya is a mosquito-borne viral disease caused by the chikungunya virus – a Togaviridae virus, transmitted by Aedes mosquitoes.