Therefore, the following assumptions are made for the interaction parameter: •γଵfollows a gamma distribution and with a mean centered at 1.2, which means the combination of 2 agents is likely to have only a small synergistic effect. •The standard deviation of ߛis 0.5 such that there is a 61% prior probability that ߛis larger than 1. This model assigns the highest probability to there being small synergistic interaction and also allows for the potential of larger synergism of the toxic profiles.