Comparative Pharmacology
Head-to-head clinical analysis: AZASAN versus IMURAN.
Peer-Reviewed Evidence
Head-to-head clinical analysis: AZASAN versus IMURAN.
AZASAN vs IMURAN
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Azathioprine is a purine analog that inhibits purine synthesis, thereby interfering with DNA and RNA synthesis. It is metabolized to 6-mercaptopurine, which inhibits T-cell activation and proliferation, leading to immunosuppression.
Imuran (azathioprine) is a purine antimetabolite that inhibits DNA synthesis by interfering with purine metabolism. It is converted in vivo to 6-mercaptopurine (6-MP), which is further metabolized to thioinosinic acid and thioguanine nucleotides. These metabolites inhibit de novo purine synthesis and incorporation of purines into nucleic acids, thereby suppressing T-cell proliferation and antibody production.
1-3 mg/kg/day orally once daily or divided twice daily; maximum dose 2.5 mg/kg/day for rheumatoid arthritis; usual dose 50-150 mg/day.
Initially 3-5 mg/kg/day orally once daily; maintenance dose 1-3 mg/kg/day orally once daily. IV dose equivalent to oral.
None Documented
None Documented
Terminal elimination half-life of azathioprine is approximately 4.5 hours (range 2–6 h), while its active metabolite 6-mercaptopurine has a half-life of 0.5–2 hours. Clinical context: Renal impairment prolongs half-life.
Azathioprine: 0.16–0.75 h; 6-mercaptopurine: 1.5–4.7 h (terminal). Extended up to 5 h in renal impairment. Context: short half-life allows daily dosing; clinical effect persists due to active metabolites.
Renal: 88% as 6-mercaptopurine and metabolites; biliary: <10%
Primarily renal excretion of inactive metabolites; 50% as 6-thiouric acid and other metabolites; <2% unchanged. Minor biliary/fecal elimination (<10% total).
Category C
Category C
Immunosuppressant
Immunosuppressant