Rheumatoid arthritis (RA) is a chronic autoimmune disease characterized by persistent inflammation and progressive joint damage, presenting significant treatment challenges. This review article provides a critical examination of the multifactorial nature of treatment resistance and failure in RA management.We explore the genetic basis of RA, including the impact of genetic variants on therapy results, including the CD84 gene, PDE3A–SLCO1C1 locus, IL6R genetic variants, MTHFR gene, and NLRP3 and CARD8 variants. The review further explores the role of epigenetic regulation in RA, highlighting how epigenetic modifications can alter gene expression and contribute to the treatment response. The formation of antidrug antibodies (ADAs) is scrutinized as a key factor in the attenuation of biologic therapy efficacy, underscoring the need for personalized treatment approaches. We also address the exacerbation of RA symptoms through cytokine storms, a phenomenon that can lead to severe systemic manifestations and complicate disease management. Lastly, the review assesses the genetic susceptibility to hepatotoxicity induced by methotrexate, a cornerstone in RA treatment, emphasizing the importance of genetic screening for personalized medication strategies. Through this comprehensive analysis, we aim to shed light on the complexities of RA treatment failures and pave the way for more effective, individualized therapeutic interventions that can improve patient outcomes in this debilitating disease.