Clinical Significance of Therapeutic Drug Level Monitoring for Mycophenolate in Patients with Extra‐Renal Systemic Lupus Erythematosus – A Systematic Review & Meta‐analysis

Among 459 reviewed abstracts, 24 met inclusion. Summarized evidence supported that clinical response was observed at MPA AUC_0-12 ≥30-35 mg h/L or Ctrough ≥1.5 mg/L. At these thresholds, therapeutic MPA levels were associated with 12-fold higher odds (95% CI 5.44-27.35, P < 0.0001, I² = 41%) of overall clinical SLE response, and 15-fold higher odds (95% CI 4.74-46.89); p < 0.0001; I²=61%) of response in patients with extra-renal manifestations. Additionally, MPA levels were 32 units higher (95% CIs 17.35-45.67) in overall SLE responders, and 39 units (95% CI 15.05-62.53) higher in patients with extra-renal manifestations. While pooled analysis did not show a significant increase in adverse events, individual studies suggested safety concerns at MPA AUC_0-12 > 60 mg h/L or Ctrough ≥2.5-3 mg/L CONCLUSIONS: This study highlights the clinical utility of TDM to guide MPA dosing to balance efficacy vs. safety in all patients with SLE, including those with extra-renal manifestations.