title: To TDM or not to TDM in lupus nephritis patients treated with MMF?
abstract: Mycophenolic acid (MPA) has become the cornerstone in the treatment of lupus nephritis. However, response rates are still far from ideal in clinical trials. Uncertainty exists regarding the correct dosing of MPA, and the recommended doses vary between recently published guidelines. Side effects are an additional problem resulting in frequent dose reduction and possible suboptimal exposure.In this review, we discuss the large variability between patients in drug exposure to MPA and the evidence for a relationship between drug exposure and efficacy in lupus nephritis. Methods for drug monitoring of MPA are discussed, and based on the current literature, we suggest as potential target levels a pre-dose level of 3.0 mg/L and an area under the concentration-versus-time curve between 35 and 45 mg h/L.Therapeutic drug monitoring may improve response rates in lupus nephritis by preventing low exposure and at the same time may reduce unnecessary side effects in patients who have high drug exposure with standard dose MPA. We specifically advise assessment of MPA drug exposure early after start of treatment and before concluding that treatment with MPA has failed.
authors.affiliation: Department of Hospital Pharmacy, Erasmus Medical Center, Rotterdam, The Netherlands Department of Internal Medicine, Erasmus Medical Center, Rotterdam, The Netherlands.
authors.forename: Teun
authors.initials: T
authors.lastname: van Gelder
authors.affiliation: Department of Nephrology, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands.
authors.forename: Jo H M
authors.initials: JH
authors.lastname: Berden
authors.affiliation: Department of Internal Medicine, Erasmus Medical Center, Rotterdam, The Netherlands.
authors.forename: Stefan P
authors.initials: SP
authors.lastname: Berger
mesh_terms: D000903:Antibiotics, Antineoplastic / Q000627:therapeutic use*; D016903:Drug Monitoring / Q000706:statistics & numerical data*; D006801:Humans; D008181:Lupus Nephritis / Q000175:diagnosis / Q000188:drug therapy*; D009173:Mycophenolic Acid / Q000627:therapeutic use*
chemical_list: D000903:Antibiotics, Antineoplastic; D009173:Mycophenolic Acid
keywords: AUC; lupus nephritis; mycophenolate mofetil; mycophenolic acid; therapeutic drug monitoring