Last reviewed 2026-04-23 · How we verify

FK506MR

FK506MR is a modified-release formulation of tacrolimus that suppresses T-cell activation by inhibiting calcineurin phosphatase.

FK506MR is a modified-release formulation of tacrolimus that suppresses T-cell activation by inhibiting calcineurin phosphatase. Used for Organ transplant rejection prevention, Autoimmune and inflammatory conditions.

At a glance

Mechanism of action

Tacrolimus is a calcineurin inhibitor that binds to FKBP12 and blocks the dephosphorylation of NFAT, preventing T-cell proliferation and cytokine production. The modified-release (MR) formulation provides sustained drug exposure with potentially improved tolerability and reduced dosing frequency compared to immediate-release tacrolimus. This mechanism makes it suitable for immunosuppression in transplantation and autoimmune conditions.

Approved indications

• Organ transplant rejection prevention
• Autoimmune and inflammatory conditions

Common side effects

• Nephrotoxicity
• Neurotoxicity
• Hypertension
• Hyperglycemia
• Infections

Key clinical trials

• A Study to Compare the Efficacy and Safety of FK506MR vs Prograf® in Patients Undergoing Liver Transplantation (PHASE3)
• A Study to Evaluate and Compare the Efficacy and Safety of FK506MR vs Prograf® in Stable Liver Transplantation Patients (PHASE3)
• A Study to Compare the Efficacy and Safety of FK506MR vs Prograf® in Patients Undergoing Kidney Transplantation (PHASE3)
• Conversion Study From Cyclosporine to FK506MR Based Immunosuppression in Kidney Transplant Subjects (PHASE3)
• A Study to Assess the Safety and Efficacy of Prograf and MR4 in Liver Transplant Recipients (PHASE3)
• A Study to Assess the Safety and Efficacy of Prograf and MR4 in Kidney Transplantation Patients (PHASE3)

Primary sources

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