Systemic Immunomodulators Flashcards
What is the mechanism of apremilast?
PDE-4 inhibitor
What are the indications for apremilast?
Psoriasis and psoriatic arthritis
What are the most common side effects of apremilast?
Diarrhea and nausea (usually go away spontaneously in 4 weeks)
What is a serious medical history item that should be screen for apremilast?
Depression/suicidality. There have been reports of depression on the medication
Renal adjustment of apremilast?
Yes, in severe renal impairment, halve the dose
Laboratory monitoring needed for apremilast?
None!
What JAK’s are affected by tofacitinib?
JAK 1 and 3
What are the most common side effects for JAK inhibitors?
URI, mild headaches, and nausea. May have decreased hgb and neutrophil count but normalizes on treatment.
Also may have increased LDL, HDL, CK, TGs, and LFTs
What JAK inhibitors are affected by Ruxolitinib?
JAK 1 and 2
What is azathioprine’s active metabolite?
6-TG (thioguanine)
What is azathioprine’s mechanism of action?
Active metabolite is produced by hypoxanthine-guanine phosphoribosyltransferase (HGPRT) pathway and shares similarities w/ endogenous purines. So, it gets incorporated in the DNA and RNA and inhibits purine metabolism and cell division. This is particularly true if the cells are fast-growing and don’t have a purine salvage pathway (like lymphocytes).
What enzymes break azathioprine into its inactive metabolites?
Xanthine oxidase and thiopurine methyltransferase
What is the clinical effect of azathioprine?
It diminishes T-cell unction and antibody production by B-cells
What medications can lead to life-threatening myelosuppression in people taking azathioprine?
Xanthine oxidase is involved in the conversion to inactive metabolites, so allopurinol or febuxostat can inhibit this and lead to elevated levels of azathioprine
What other medications besides allopurinol and febuxostat can increase the risk of myelosuppression with azathioprine?
ACEi, sulfasalzine, and concomitant use of folate antagonists
What test must be checked before starting azathioprine?
TPMT activty
Important side effects of azathioprine?
Leukopenia, thrombocytopenia, and immunosuppression (correlates with low TPMT activity)
What cancer risks are increased in azathioprine?
Squamous cell carcinoma and lymphoma (non-Hodgkin’s B-cell lymphoma)
No clear evidence that this actually occurs with doses used in dermatologic dz
What are the most common side effects of azathioprine?
Gastrointestinal side effects: nausea, vomiting, and diarrhea (often between first and tenth day of therapy), gastritis and pancreatitis
When does hypersensitivity syndrome usually occur?
Usually between first and fourth week of therapy and more common in those getting MTX or cyclosporin
What effect on the killed hepatitis B vaccine do azathioprine and prednisone have?
These have been shown to decrease the response of the vaccine
If azathioprine is given with a TNF-a inhibitor, what cancer is the person at risk for?
Increased risk of hepatosplenic T-cell lymphoma
What baseline tests should be done before starting azathioprine?
Pregnancy test, tuberculin skin test
What is the mechanism of action for mycophenolate mofetil?
Binds and inhibits inosine monophosphate dehydrogenase
This is an important enzyme for de novo synthesis of purines - which is essential in activated lymphocytes