Stability of periodic solution in a model of CAR-T cell immunotherapy

I will talk about a model of CAR-T (Chimeric Antigen Receptor T) cell therapy that was presented in paper O. León-Triana et al.. (Cancers, 2021). I consider an system of 4 ODEs with impulses and continuous periodic function describing contiguous treatment. I prove existence of periodic, tumour-free, solution and study its stability. In particular I justify global convergence to this solution under suitable condition.