Adding an additional B strain to the seasonal influenza vaccine could reap substantial cost-savings for society and third party payers, even if the QIV enjoyed a significant price premium over TIV. It is not common for a new medical technology, especially one that is a variation of an existing technology, to immediately generate cost-savings[9
]. (Most technologies require additional costs to result in health benefits.) Such savings may reassure third party payers of the value of covering a more expensive QIV as they would be likely to recoup this investment through averting healthcare costs. This in turn could facilitate adoption and also motivate additional scientists, developers, and manufacturers to enter the QIV market and investigate the possibility of adding even more strains to the vaccine. Moreover, the cost-savings could be greater in the coming decade as the Advisory Committee on Immunization Practices (ACIP) has increased the scope of whom they recommend should be vaccinated[10
], which could in turn increase coverage of the overall population.
These findings also highlight the difficulty in accurately predicting the circulating influenza strains for the upcoming influenza season and the cost of inaccurate predictions. For example, missing on the B strain for the 2007–2008 influenza season seems to have cost third party payers well over $100 million and society well over $1 billion. This year 29% of all influenza were influenza B viruses, of which 98% were from the Yamagata lineage, while the TIV vaccine was manufactured with the Victoria lineage[3
]. Although there are continuing efforts to improve the accuracy of strain predictions, adding more strains to the seasonal vaccine could be a promising route.
Currently, only MedImmune’s QIV has FDA approval , but GlaxoSmithKline, Sanofi Pasteur, and Novartis Vaccines are in various stages of QIV development; their QIV formulations are expected to reach the market for the 2013–14 influenza season [11
]. MedImmune plans to discontinue the current TIV FluMist and offer only the FluMist Quadrivalent vaccine for the 2013–14 influenza season, where as GlaxoSmithKline and Sanofi Pasteur plan to introduce their QIV formulations in conjunction with their current TIV vaccines[11
Every model is a simplification of real life and cannot account for every possible factor and outcome[12
]. Our results assume that QIV vaccine production could have been high enough to cover the number of TIV doses administered each year, which should eventually be possible, but could require an expansion in production capacity to accommodate the additional strain[2
]. Therefore, the realization of cost-savings would depend on the timing of replacement of TIV with QIV: more slowly for gradual replacement and more near term if companies such as MedImmune do rapid en masse replacement[11
]. Expansion of vaccine manufacturing capacity since the 2005–06 season and the inception production methods (e.g., cell culture) could further foster industry’s ability to replace TIV[11
]. On the other hand, additional limitations may make our estimates of the cost-savings conservative. Our study used the adjusted vaccine production numbers from Reed et al.; using less conservative numbers would increase QIV’s cost-savings by averting more influenza outcomes. Current and future broader target population recommendations may further enhance the economic value of the QIV. It also did not account for over-the-counter self-treatment and all additional costs from medical problems (e.g., congestive heart failure or pulmonary disease exacerbations) that may be precipitated by influenza. Our model did not include any potential adverse events since reported ones are infrequent and relatively minor (e.g., runny nose, nasal congestion, sore throat)[1
] and evidence does not suggest a higher rate than TIV. Our study draws from the Reed et al. study and therefore is subject to its limitations and assumptions.
In conclusion, the addition of the influenza B strain to convert the TIV into a QIV could result in substantial cost-savings to society and third party payers, even when the cost of QIV is significantly higher, information which could be useful to insurers (e.g., coverage decisions), manufacturers (e.g., production and pricing), developers (e.g., prioritizing research), and policy makers (e.g., adoption).