How long does it take for Besudil/Yilaike to be effective in treating pulmonary rejection?

Belumosudil mesylate tablets (Belumosudil), as a ROCK2 inhibitor, was initially used for chronic graft-versus-host disease, but its immunomodulatory mechanism has also attracted attention in the field of organ transplantation, especially in the management of rejection after lung transplantation. For patients and doctors, the most concerning question is how long it will take for Besudil to be effective in treating pulmonary rejection.

The onset time of besudil is closely related to individual patient differences, disease severity and previous treatment history. Its main mechanism of action is to restore immune tolerance by regulating T cell differentiation and cytokine balance. Generally speaking, it takes a certain amount of time for a drug to reach a steady-state concentration after entering the body, thereby gradually suppressing abnormal immune responses. Clinical experience shows that when besudil is used to treat immune rejection-related diseases, some patients can observe improvement in respiratory symptoms, such as cough reduction or stabilization of lung function indicators, within a few weeks, while structural improvement or imaging changes usually take several months.

Compared with traditional glucocorticoids or calcineurin inhibitors, the advantage of besudil is that it can control the immune response without significantly increasing the risk of infection. It restores the function of regulatory T cells (Treg), allowing the immune system to gradually re-establish tolerance rather than completely suppressing immunity. Therefore, the "effect" of a drug is often gradual rather than immediate.

The study suggested that the therapeutic effect of besudil in the stage of chronic rejection or fibrosis after lung transplantation is particularly worth looking forward to. Its ability to inhibit the ROCK2 pathway can slow down the progression of airway fibrosis and maintain the structural stability of lung tissue. Long-term use may help delay the decline of graft function. This mode of action means that besudil is not a simple anti-inflammatory drug, but a "remodeling" immune modulator.

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