Once you start taking Besudil/Yilaike, can you stop taking it at will?

Belumosudil mesylate tablets (Belumosudil) is a selective Rho-associated coiled-coil protein kinase 2 (ROCK2) inhibitor. It was originally developed by the American company Kadmon and is mainly used to treat immune-related diseases such as chronic graft-versus-host disease (cGVHD). The drug regulates the balance of T cell subsets and improves tissue fibrosis and inflammatory responses by inhibiting the ROCK2 signaling pathway, thereby exerting a long-lasting and systemic immune regulatory effect in clinical practice. Since its mechanism involves deep regulation of the immune system, patients are not advised to stop taking it at will once they start taking it.

From a pharmacological point of view, besudil needs to maintain a stable concentration in the body to achieve optimal efficacy. Abrupt discontinuation of the drug may re-imbalance the immune system, causing a rebound or worsening of symptoms, especially in patients with chronic graft-versus-host disease. In addition, if the drug is discontinued and then used again, the body's immune response may also undergo changes in tolerance or sensitivity, affecting the subsequent effects of the drug. Therefore, when deciding to adjust or stop Besudil treatment, it must be done under the guidance of a doctor, and the drug concentration and changes in the condition must be gradually evaluated.

In treatment experience, besudil is often used as a long-term maintenance medication. The U.S. FDA clearly states in its drug information guide that if patients experience obvious adverse reactions, they should adjust the dosage under the guidance of a doctor instead of stopping the drug on their own. Some patients may experience mild transaminase elevations, fatigue, or mild gastrointestinal reactions while taking the drug, but these reactions can often be alleviated through dose adjustment or adjuvant treatment. Stopping medication at will may destroy the stability of the efficacy and increase the risk of recurrence.

For patients who are already in remission, if discontinuation of medication is considered, doctors will develop a management plan of "reduce-observation-maintenance" based on individual circumstances rather than stopping immediately. Patients should follow the medical plan for regular follow-up visits and monitor liver and kidney function, immune cell ratios and inflammatory indicators to ensure a safe transition.

Reference: https://www.drugs.com/pro/rezurock.html