A vaccine program for Epstein-Barr virus would likely be ‘highly cost-effective’ at preventing MS in an Australian setting, particularly if targeted at young adolescents, researchers have found.
While the clinical benefits of EBV immunisation remain purely theoretical at present, the modelling highlights the potential significant public health upside were a vaccine to become available, according to the University of Tasmania team.
Developed using specialised decision analysis software, the model simulated the incidence and subsequent progression of MS in a general Australian population, how this would be impacted by a hypothetical EBV vaccine, and the related direct and indirect costs.
Vaccine efficacy was assumed to be 78% based on results of the latest and largest phase II RCT of an EBV vaccine (the recombinant Gp350 vaccine) currently in development.
These costs were then compared with the likely financial impact of a national vaccination program, assuming per-person costs between $175 and $615 – in line with those for administering the required two doses of other available Australian herpesvirus vaccines (ie Zostavax and Shingrix).
Calculations revealed that even with a vaccine at the top end of the cost scale, adding EBV to infant immunisations would have small societal benefits – saving $40 and adding 0.003 quality adjusted life years (QALY) for each person vaccinated.
But a second option involving vaccination at age 12 would be “highly cost-effective”, the researchers reported in Journal of Neurology, Neurosurgery & Psychiatry (link here).
Under this scenario, total lifetime costs were reduced by $452 per-person, while QALYs gained more than doubled to 0.007, found the team, from the Menzies Institute for Medical Research.
This difference could primarily be explained by the vanishingly low MS incidence in children and young adults, although it also reflected nuances of the statistical modelling used, they wrote.
“Vaccination strategies that are targeted at adolescents would also be beneficial in terms of vaccination implementation as adolescents could be more easily reached through school- based programmes by piggybacking on current vaccine programmes (eg, HPV vaccine) to ensure high coverage, the authors added.
While the gains in QALYs due to vaccination did seem small, they stressed this was to be expected when analysing the effectives of prevention of a relatively rare disease in which gains of small fractions of years were the norm.
“However, if extrapolate to the entire population, vaccination at age 0 would save $A1017 million and gain 76 268 QALYs,” they said.
“When only the direct costs were considered, the EBV vaccination was cost- effective at age 12 only.”
“Therefore, the future use of EBV vaccine to prevent MS is highly likely to be cost-effective, particularly when administered at age 12 given the conservative and realistic assumptions around the costs and effectiveness modelled in our study.”
Previous research showed the overall incidence of MS in Australia was currently 6.1/100,000 people, with direct costs of the disease ranging from $18,806 to $26,925 per person, depending on severity, the authors noted.
Indirect costs were between $24,517 and $51,424.