Tocilizumab is a medication used to treat rheumatoid arthritis, a condition where the immune system attacks the joints. This medication works by blocking a protein in the body that causes inflammation. It helps reduce joint pain, swelling, and damage to the bones. The medication is given as an injection under the skin (subcutaneous injection). It helps slow down the progression of joint damage and can improve daily activities for people with rheumatoid arthritis.

HR-pQCT (High-Resolution peripheral Quantitative Computed Tomography) is an imaging technique used in this study to measure bone damage. While this is not a medication, it is an important part of the trial as it helps doctors see detailed images of the bones and measure how the treatment affects bone healing.

Rheumatoid Arthritis – A chronic inflammatory disease that primarily affects the joints throughout the body. The condition causes the immune system to mistakenly attack the joint linings, leading to inflammation, swelling, and pain. Over time, this ongoing inflammation can cause damage to the joint tissue and bones, resulting in joint deformity and reduced mobility. The disease typically affects multiple joints symmetrically, meaning if one hand is affected, the other hand is usually affected as well. Rheumatoid arthritis often begins gradually, with symptoms developing over weeks or months, and tends to affect smaller joints first, such as those in the fingers and toes. The condition can also cause fatigue, general weakness, and occasional fever.