I am new to RNA-seq analysis. I have data from RNA-seq performed on serial samples (before treatment, after treatment 1, after treatment 2) from 3 biological replicates (3 different patients). I was able to use DESeq2 in order to obtain the top differentially expressed gene sets. Since patients samples can be highly heterogeneous, I would also like to analyze the serial samples from each patient individually only for exploratory purpose. What is the best way to do that?