Factors associated with the pricing of childhood vaccines in the U.S. public sector.

Vaccine purchase cost has grown substantially over the last few decades. A closer look at vaccine prices reveals that not all vaccines shared the same increasing pattern. Various factors, such as vaccine attributes, competition, and supply shortages, could relate to price changes. In this study, we examined whether a variety of factors influenced the prices of noninfluenza childhood vaccines purchased in the public sector from 1996 to 2014. The association differed among price-capped vaccines and combination vaccines. There was an increasing time trend in real prices for non-price-capped vaccines, which was mostly offset by the effect of market longevity. The effect of competition in lowering prices was more pronounced among non-price-capped vaccines when manufacturer and vaccine component fixed effects were excluded. Supply shortage, manufacturer name change, and number of vaccine doses in series showed no effect. The results may help policy makers better understand price behaviors and make more informed decisions in vaccine planning and financing.