A vaccine for CMV has been in development for over 50 years yet it seems we are still some way off the reality. CMV research took off in the 1970s, when a landmark review described CMV’s impact on the health on babies for the first time . It remains the case that currently, there is no CMV vaccine available to prevent congenital cytomegalovirus (CMV). CMV has been on the list in the US for the highest priority for vaccine development since 2000. Despite the pressing public health need, CMV vaccine development has been difficult in part due to the virus’s ability to evade immunity.
Yet CMV vaccines are still in the research and development stage, with the hope and expectation that there could be one available in the next 5 to 10 years. There have been no shortage of players in the market and a variety of different approaches have been taken to developing a vaccine. At one time there were as many as 14 teams from some of the world’s largest pharma companies racing to be the first. There is no doubt that the development work carried out in connection with the Covid vaccine working with RNAs has been beneficial to those using this method to develop a CMV vaccine.
Moderna Leads the Way
Consequently, currently the most promising candidate is Covid vaccine big name, Moderna. Moderna is evaluating the safety and efficacy of a messenger RNA CMV vaccine (mRNA-1647) against primary CMV infection in women who are between 16 and 40 years of age in a study known as CMVictory. Their CMV vaccine is likely to be the first to market as Moderna’s treatment has reached the furthest along of any company, currently being on phase III of its trial. However “furthest” means a study completion date of July 2025, with a commercial launch not happening until around 2026-2027. Although mRNA vaccines are proving effective it has yet to be seen whether they are able to remain potent and offer a long-lasting immune response to CMV.
Another company Merck has also completed phase II of its trial drug V160, this is an attenuated vaccine that mimics the CMV infection. Indications from the trial so far are that the drug whilst effective is not effective enough at present. GSK also has a vaccine in its pipeline. Their vaccine is a subunit vaccine (contain pieces of the virus) and this approach to develop a CMV vaccine has apparently been the most successful to date. Evaluated in a phase I trial, three-doses administered to CMV-seronegative recipients showed no serious adverse events and robust antibody responses.
It is encouraging that the vaccine industry has made significant advances in our understanding of CMV in recent years, leading to a range of emerging technologies that could soon see a breakthrough. The good news is that a lot of work and research is happening in this sector and progress is most definitely being made. The road to a successful vaccine is often long but there would appear to be hope in the not too distant future.
In the meantime risk reduction remains the best way to prevent this devastating virus. How to reduce your risk