The promise of a safe and effective RSV vaccine is more realistic than ever before. Although no vaccine has entered phase 3 randomized clinical trials, the pharmaceutical landscape suggests a number of good candidates have well progressed into clinical development. On July 8th, the PATH Vaccine Snapshot website has been updated (sites.path.org/vaccinedevelopment/respiratory-syncytial-virus-rsv/).
One of the RSV vaccines which has now entered clinical development is an Modified Vaccinia Virus Ankara (MVA)-based RSV vaccine. For over 15 years MVA-based RSV vaccines have been developed at preclinical stage, but never went beyond. For the first time, it has now been combined with an adenovirus RSV vaccine to induce strong protective immunity against RSV.
The potential and mechanisms of MVA-based vaccines is discussed by Altenburg. MVA is a strongly attenuated vaccinia strain which can encode viral proteins making MVA a suitable candidate vaccine technology. Because MVA does not replicate in primates it has a favorable safety profile. According to www.clinicaltrials.gov the adenovector-MVA RSV vaccine phase 1 trial should have primary outcome data by now.
*Modified Vaccinia Virus Ankara (MVA) as Production Platform for Vaccines against Influenza and Other Viral Respiratory Diseases