ERBB2 and breast cancer: We will review this prior experience (see Table 1 for summarized data) and, because combinatorial strategies are the next stage in development for the cancer immunotherapy field, we will provide preliminary clinical data from the initial safety phase of a phase II clinical trial testing a combination of a self-replicating RNA and the anti-PD-1 antibody pembrolizumab in advanced HER2 + breast cancer patients.