Reply to: assessing physico-chemical compatibility of concomitantly diluted antiemetics including palonosetron-HCl and fosaprepitant dimeglumine

It is the phenomenon, precipitation of aprepitant, which the limit of <0.2 % aprepitant growth is designed to prevent. Our internal shelf-life models which are based on the true aqueous solubility of aprepitant and include maximum levels of degradate growth in the drug substance as well as degradate growth rates in the drug product only allow 0.2 % aprepitant growth during the reconstituted inuse period. Given these data and the unpredictable nature of the onset precipitation from a supersaturated solution, we are not able to support a widening limit of acceptable degradate growth to more than that proposed by Sun et al. should be considered the definitive source for the degradate growth limit. Dear Editor,