Mercaptopurine (6-MP)
General information
Class/mechanism: Purine analog of adenine and hypoxanthine, antimetabolite that interferes with DNA synthesis. Mercaptopurine competes with hypoxanthine and guanine for the enzyme hypoxanthine-guanine phosphoribosyltransferase (HGPRTase) and is converted to thioinosinic acid (TIMP). TIMP inhibits reactions that typically involve inosinic acid (IMP), such as its conversion to xanthylic acid (XMP) and adenylic acid (AMP) via adenylosuccinate (SAMP). TIMP is also converted to 6-methylthioinosinate (MTIMP); TIMP and MTIMP have been observed to inhibit glutamine-5-phosphoribosylpyrophosphate amidotransferase, which is an early enzyme in the de novo pathway of purine ribonucleotide synthesis. Mercaptopurine is structurally and functionally similar to Thioguanine (Tabloid).[1][2][3][4]
Route: PO
Extravasation: n/a
For conciseness and simplicity, HemOnc.org currently will focus on treatment regimens and not list information such as: renal/hepatic dose adjustments, metabolism (including CYP450), excretion, monitoring parameters (although this will be considered for checklists), or manufacturer. Instead, for the most current information, please refer to your preferred pharmacopeias such as Micromedex, Lexicomp, UpToDate (courtesy of Lexicomp), or the prescribing information.[1]
Diseases for which it is used
- Acute myeloid leukemia
- Acute promyelocytic leukemia
- B-cell acute lymphoblastic leukemia
- CNS leukemia
- Langerhans cell histiocytosis
- T-cell acute lymphoblastic leukemia
Diseases for which it was used
Patient drug information
- Mercaptopurine (Purinethol) patient drug information (Chemocare)[5]
- Mercaptopurine (Purinethol) patient drug information (UpToDate)[6]
History of changes in FDA indication
- 1953-09-11: Initial FDA approval
- 2003-01-10 (oldest label on Drugs @ FDA): Indicated for remission induction and maintenance therapy of acute lymphatic leukemia. (No supporting studies are cited)
- 2014-04-28: Purixan (mercaptopurine oral suspension formulation) FDA approved for the treatment of patients with acute lymphoblastic leukemia (ALL) as a component of a combination maintenance therapy regimen. (No supporting studies are cited)
History of changes in EMA indication
- 1953-09-11: EURD
Also known as
- Generic names: 6-MP, 6-Mercaptopurine
- Brand names: Purinethol, Purixan (oral suspension formulation), Xaluprine
References
- ↑ 1.0 1.1 Mercaptopurine (Purinethol) package insert
- ↑ Mercaptopurine (Purinethol) package insert (locally hosted backup)
- ↑ Mercaptopurine (Purixan) package insert
- ↑ Mercaptopurine (Purixan) package insert (locally hosted backup)
- ↑ Mercaptopurine (Purinethol) patient drug information (Chemocare)
- ↑ Mercaptopurine (Purinethol) patient drug information (UpToDate)
- Drugs
- Oral medications
- Antimetabolites
- Purine analogs
- Immunosuppressants
- Acute myeloid leukemia medications
- Acute promyelocytic leukemia medications
- B-cell acute lymphoblastic leukemia medications
- CNS leukemia medications
- Langerhans cell histiocytosis medications
- T-cell acute lymphoblastic leukemia medications
- Gestational trophoblastic neoplasia medications (historic)
- FDA approved in 1953
- FDA approved in 2014
- EMA approved in 1953
- WHO Essential Cancer Medicine