We have designed a randomized controlled trial (RCT) to investigate the mechanism of action and safety of the KPR method in MM.<h4>Objective</h4>This RCT aims to assess whether a KPR herbal formula combined with standard bortezomib-based therapy improves the immune microenvironment via the PHF19-EZH2-H3K27me3 epigenetic axis to restore immune function in MM, providing a mechanistic basis for integrating TCM into evidence-based oncology care in relapsed or refractory patients.<h4>Methods</h4>This is a single-center, prospective RCT involving patients with MM. Here, EZH2 is linked to Miyoshi myopathy.