Mycophenolic Acid DI Flashcards
MoA of mycophenolic acid (MPA)
Inhibits IMPDH which interferes with purine metabolism required for lymphocyte development
Factors affecting MPA PK
Time after transplantation, drug interactions, enterohepatic circulation (especially with concurrent CNI therapy), concurrent disease states, food, ethnicity, possibly gender
Effect of CYA inhibiting the MRP2 transporter
Reduced enterohepatic circulation of MPAG to MPA, reduced MPA AUC
Effect of tacrolimus minimally inhibiting MRP2
Higher MPA AUC (lower daily MPA doses divided)
Effect of cholestyramine and bile acid resins
Reduces MPA AUC
Effect of ABX on MPA
Reduces MPA’s AUC
ABX that decrease MPA AUC
Norfloxacin, metronidazole, ciprofloxacin, amoxicillin with clauvanic acid, rifampin
Drugs that affect renal elimination of MPA
Acyclovir, ganciclovir, co-trimoxazole- they all compete with MPAG for tubular secretion which may increase MPAG concentrations
COCs and MMF
Use a second barrier method
MPA and MPAG on protein binding
May alter binding of drugs to albumin (phenytoin, ASA)
Glucocorticoids and MPA
Steroids may increase MPA metabolism
MPA drugs
Mycophenolate mofetil (MMF) (Cellcept); mycophenolic acid sodium (MPS) (Myfortic)
Mycophenolate mofetil brand name
CellCept
Mycophenolate acid sodium brand name
Myfortic
Which MPA drug is a prodrug?
Mycophenolate mofetil/CellCept
Is CellCept regular or delayed release?
Regular
Is Myfortic regular or delayed release?
Delayed
Mycophenolic acid sodium to mycophenolate mofetil dose conversion
720mg MPS to 1000mg MMF
Are MMF and MPS interchangeble?
No
MPA TDM
There is interpatient variability in MPA PK and clinical response, so TDM remains controversial
Suggested utility of MPA TDM
CNI minimization or sparing protocols
Switch between CNI protocols
Patients with high immunologic risk
The relationship of MPA AUC and/or trough with MPA ADEs aren’t consistent
ADEs of MPA
N/V/D, dyspepsia (may be more common with TAC/MPA combo therapy)
Leukopenia, neutropenia, anemia, thrombocytopenia
Opportunistic infections
Dizziness, insomnia, headache
As renal function declines, what should you do to the MPA dose?
Adjust the MPA dose lower with a longer interval
