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Mercaptopurine (Purinethol)

Academisch Medisch Centrum - Universiteit van Amsterdam (AMC-UvA) · Phase 3 active Small molecule

Mercaptopurine is a purine analog that inhibits de novo purine synthesis and is converted to active metabolites that interfere with DNA and RNA synthesis, leading to cell death.

Mercaptopurine is a purine analog that inhibits de novo purine synthesis and is converted to active metabolites that interfere with DNA and RNA synthesis, leading to cell death. Used for Acute lymphoblastic leukemia (ALL), Chronic myeloid leukemia (CML), Inflammatory bowel disease (Crohn's disease, ulcerative colitis).

At a glance

Generic nameMercaptopurine (Purinethol)
Also known asPurinethol
SponsorAcademisch Medisch Centrum - Universiteit van Amsterdam (AMC-UvA)
Drug classPurine analog antimetabolite
TargetHGPRT (hypoxanthine-guanine phosphoribosyltransferase); inosinate dehydrogenase
ModalitySmall molecule
Therapeutic areaOncology; Immunology
PhasePhase 3

Mechanism of action

Mercaptopurine is metabolized to thioinosinate monophosphate, which inhibits inosinate dehydrogenase and feedback-inhibits PRPP amidotransferase, blocking purine synthesis. The active metabolites also incorporate into DNA and RNA, disrupting nucleic acid synthesis and function in rapidly dividing cells, particularly lymphocytes and leukemic cells.

Approved indications

Common side effects

Key clinical trials

Primary sources

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SourceUsed for
ClinicalTrials.govTrial enrolment, design, endpoints, results

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