A 42-year-old woman from Delhi presents with a 6-month history of symmetrical pain and swelling of the small joints of both hands, wrists, and knees. Morning stiffness lasts 2 hours. On examination, she has soft tissue swelling over the PIP and MCP joints bilaterally, with mild ulnar deviation of the fingers. Laboratory investigations show: ESR 68 mm/hr, CRP 12 mg/dL, RF 120 IU/mL (normal <20), anti-CCP antibody 85 U/mL (normal <20). X-ray of hands shows periarticular osteopenia and early marginal erosions. She has no extra-articular manifestations. What is the most appropriate next step in management?