Standardization of LC-MS for Therapeutic Drug Monitoring of Tacrolimus

The immunosuppressant drug tacrolimus is the most commonly prescribed calcineurin inhibitor for the prophylaxis of rejection following kidney transplantation. In this application note, the authors have performed a proficiency-testing survey of laboratories using the Waters® MassTrak Immunosuppressants Kit, on the ACQUITY® TQD LC-MS/MS instrument, to assess whether inter-laboratory imprecision could be improved through standardization of LC-MS analysis.