The goal of this clinical trial is to learn if metformin and antifibrotic drugs (pirfenidone) can modulate fibrosis and improve treatment outcomes in patients with oral submucous fibrosis (OSF). The study also aims to investigate the molecular mechanisms underlying their effects on exosome secretion and protein expression. The main questions it aims to answer are: Do metformin and antifibrotic drugs alter exosome secretion and biological activity in OSF cell lines? What molecular pathways are influenced by these drugs in modulating fibrosis? Does treatment with metformin and antifibrotic drugs improve clinical outcomes in OSF patients? Researchers will compare metformin and antifibrotic drug treatment groups to a control group to see if these drugs lead to significant changes in fibrosis-related exosomal protein expression and clinical improvement in OSF patients. Participants will : Undergo in vitro experiments on OSF cell lines to analyze drug effects using qPCR, Western Blot, and LCMS for protein profiling. Participate in a randomized, double-blind clinical trial where they receive metformin, antifibrotic drugs, or a placebo. Undergo clinical evaluations and laboratory tests to assess treatment efficacy. This study aims to develop an affordable and effective fibrosis-targeted therapy for OSF by repurposing metformin, potentially improving patient outcomes and reducing the risk of malignant transformation.