From the Guidelines
Mycophenolate requires regular laboratory monitoring, including CBC with differential and CMP at baseline, 2–3 weeks after starting and 2–3 weeks after any dose increase, and every 3 months once on a stable dose, to ensure safety and efficacy. The monitoring schedule is based on the potential for mycophenolate to cause marrow suppression, hepatotoxicity, and other adverse effects 1.
Key Monitoring Parameters
- CBC with differential to monitor for signs of bone marrow suppression, such as leukopenia and thrombocytopenia
- CMP to monitor liver function and electrolyte levels
- Full body skin examination, preferably by a dermatologist, annually to monitor for skin cancer
Monitoring Frequency
- Baseline: CBC with differential and CMP
- 2-3 weeks after starting: CBC with differential and CMP
- 2-3 weeks after any dose increase: CBC with differential and CMP
- Every 3 months once on a stable dose: CBC with differential and CMP
Special Considerations
- Patients with renal impairment may require more frequent monitoring, as mycophenolate metabolites can accumulate 1
- Patients should be monitored for signs of infection, as mycophenolate can increase the risk of viral, bacterial, and mycobacterial infections 1
- Therapeutic drug monitoring of mycophenolate levels is not routinely recommended, but may be considered in select cases such as suspected non-adherence or treatment failure 1
From the FDA Drug Label
Patients receiving mycophenolate mofetil should be monitored for neutropenia . Consider monitoring with complete blood counts weekly for the first month, twice monthly for the second and third months, and monthly for the remainder of the first year Monitoring infected patients for clinical and laboratory signs of active HBV or HCV infection is recommended.
The laboratory monitoring requirements for mycophenolate (Cellcept) therapy include:
- Complete blood counts: weekly for the first month, twice monthly for the second and third months, and monthly for the remainder of the first year to monitor for neutropenia
- Clinical and laboratory signs: of active HBV or HCV infection in infected patients 2
From the Research
Laboratory Monitoring Requirements for Mycophenolate Therapy
- Mycophenolate acid (MPA) concentrations are used for therapeutic drug monitoring of patients receiving mycophenolic mofetil or mycophenolate sodium 3
- Predose plasma MPA concentrations can be measured using a semi-automated enzyme-multiplied immunoassay to relate to adverse events and clinical status 4
- A therapeutic range of 1 to 3.5mg/L (by immunoassay) is applicable in liver allograft recipients given adjunctive mycophenolate mofetil 4
Methods for Monitoring Mycophenolic Acid
- High performance liquid chromatography combined with UV detection (HPLC-UV) and isotope dilution liquid chromatography tandem mass spectrometry (ID-LC-MS/MS) can be used for MPA monitoring 5
- HPLC-UV testing can be considered suitable for routine therapeutic drug monitoring of MPA in the clinical setting with high precision 5
- ID-LC-MS/MS methodology should be given preference over HPLC-UV analysis whenever feasible due to the risk of unforeseen analytical interference 5
Sampling Strategies for Therapeutic Drug Monitoring
- A 12-hour area under the concentration-time curve (AUC) is recommended for therapeutic drug monitoring, but limited sampling strategies can be used for routine monitoring 6
- Sparse sample algorithms using C(0), C(1), C(2), C(3), C(4), and/or C(6) can estimate 12-hour AUC with good correlation 6
- A 3-point algorithm (C(0), C(1), and C(2)) can be used for MPA therapeutic drug monitoring in stable renal transplant patients due to the good correlation with drug exposure 6