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Valneva Initiates Phase I Clinical Study to Evaluate Its Single-Shot Vaccine Candidate against Chikungunya


Valneva SE, a fully integrated commercial stage biotech company focused on developing innovative, lifesaving vaccines, today announced the initiation of a Phase I clinical trial in the U.S. to evaluate the safety and immunogenicity of VLA1553, its live-attenuated vaccine candidate against Chikungunya.

The Phase I clinical trial is a randomized, observer-blinded, dose-escalation, multi-center study. It will investigate three different dose levels of VLA1553 in approximately 120 healthy adults vaccinated with a single-shot immunization.

The trial design includes the investigation of antibody persistence and an additional vaccination using the highest dose of VLA1553 at 6 and 12 months. This re-vaccination will serve as an intrinsic human viral challenge, aiming to demonstrate that subjects are protected from vaccine-induced viremia thereby indicating potential efficacy of VLA1553 early in clinical development.

First data from the trial are expected to be available early 2019.

Wolfgang Bender, MD, PhD, Chief Medical Officer of Valneva commented “We are proud to contribute to the ongoing global efforts to develop effective prevention against the increasing threat to public health caused by the Chikungunya virus. We have developed a sophisticated Phase I design with the intent to provide us with an early indication of competitive advantage that we anticipate for our vaccine candidate.”

About Chikungunya

Chikungunya is a mosquito-borne viral disease caused by the Chikungunya virus (CHIKV), a Togaviridae virus, transmitted by Aedes mosquitoes. Clinical symptoms include acute onset of fever, debilitating joint and muscle pain, headache, nausea and rash,  potentially developing into long-term, serious health  impairments. Chikungunya virus causes clinical illness in 72-92%  of infected humans around 4 to 7 days after an infected mosquito bite1. Complications resulting from the disease include visual, neurological, heart and gastrointestinal manifestations; fatalities have been reported (case fatality rates of 0.1% to 4.9% from epidemics)1in elderly patients at higher risk. Chikungunya outbreaks have been reported in Asia, Africa, the Americas and recently (2017) in Europe. As of 2017, there have been more than one million reported cases in the Americas2and the economic impact is considered to be significant (e.g. Columbia outbreak 2014: $73.6m3). The medical and economic burden is expected to grow as the CHIKV primary mosquito vectors continue to further spread geographically. There are no preventive vaccines or  effective treatments available and, as such, Chikungunya is  considered to be a major public health threat.

About VLA1553

VLA1553 is a monovalent, single dose, live-attenuated vaccine candidate for protection against Chikungunya. It is designed for prophylactic, active, single-dose immunization against  Chikungunya in humans over one year old. The vaccine aims for  long-lasting protection and an anticipated safety profile similar to  licensed vaccines for active immunization in adults and children.  The target population segments are travellers, military personnel  and individuals at risk living in endemic regions. The global  market for vaccines against Chikungunya is estimated at up to  €500 million annually4. VLA1553 is based on an infectious clone (CHIKV LR2006-OPY1) attenuated by deleting a major part of the gene encoding the non-structural replicase complex protein nsP3, aiming for protection against various Chikungunya virus outbreak phylogroups and strains5. In pre-clinical development a single-vaccine shot was shown to be highly immunogenic in vaccinated Non-Human Primates (NHP) (cynomolgus macaques) and  showed no signs of viremia after challenge6. In NHPs, VLA1553  induced a strong, long lasting (more than 300 days) neutralizing  antibody response comparable to wild-type CHIKV infections  combined with a good safety profile.

About Valneva SE

Valneva is a fully integrated, commercial stage biotech company focused on developing innovative life-saving vaccines. Valneva’s portfolio includes two commercial vaccines for travelers: IXIARO®/JESPECT® indicated for the prevention of Japanese  encephalitis and DUKORAL® indicated for the prevention of  cholera and, in some countries, prevention of diarrhea caused by  ETEC. The Company has proprietary vaccines in development including a unique vaccine against Lyme disease. Valneva has operations in Austria, Sweden, the United Kingdom, France,  Canada and the US with over 450 employees. More information is available at

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