Evaluation of the thermal stability of a novel strain of live-attenuated mumps vaccine (RS-12 strain) lyophilized in different stabilizers

The stability of live-attenuated viral vaccines is important for immunization efficacy. Here, the thermostabilities of lyophilized live-attenuated mumps vaccine formulations in two different stabilizers, a trehalose dihydrate-based stabilizer and a stabilizer containing sucrose, human serum albumin and sorbitol were investigated using accelerated stability tests at 4 degrees C, 25 degrees C and 37 degrees C at time points between 4h (every 4h for the first 24 h) and 1 week. Even under the harshest storage conditions of 37 degrees C for 1 week, the 50% cell culture infective dose (CCID50) determined from titrations in Vero cells dropped by less than 10-fold using each stabilizer formulation and thus complied with the World Health Organization's requirements for the potency of live-attenuated mumps vaccines. However, as the half-life of the RS-12 strain mumps virus infectivity was lengthened substantially at elevated temperatures using the trehalose dihydrate (TD)-based stabilizer, this stabilizer is recommended for vaccine use. (C) 2013 Elsevier B.V. All rights reserved.