Leukin50 mg

Leukin is a purine analog antimetabolite (thiopurine) chemotherapy agent used mainly in the treatment of blood cancers, always under specialist (oncology/hematology) supervision.

Established / FDA-approved use

• Acute lymphoblastic leukemia (ALL): Leukin is indicated as part of combination chemotherapy for the maintenance phase of treatment of ALL in adults and children. It is not effective as a single agent for remission induction and is not indicated for acute myeloid leukemia, CNS leukemia, or solid tumors.

Guideline-supported / commonly used off-label

• Inflammatory bowel disease (Crohn's disease, ulcerative colitis): Leukin is used off-label (though supported by clinical practice and some guidelines) as a steroid-sparing immunosuppressant/maintenance agent when other thiopurines (e.g., azathioprine) are not tolerated, and in select autoimmune conditions, always under specialist supervision.

Leukin is always used as part of a combination regimen decided by a specialist; it should never be started, changed, or stopped without direct medical supervision.

Each tablet typically contains Mercaptopurine 50 mg as the active ingredient, along with pharmaceutical excipients (e.g., lactose, starch, magnesium stearate) that may vary by manufacturer. Confirm exact composition on the product label/pack insert of the specific brand dispensed.

Leukin is an antineoplastic and immunosuppressant drug belonging to the thiopurine (purine analog) class. It is a cytotoxic chemotherapy medicine used mainly for maintenance treatment of acute lymphoblastic leukemia, and in selected cases for inflammatory bowel disease, as part of a physician-supervised treatment plan.

Leukin works by interfering with DNA and RNA synthesis in rapidly dividing cells, which slows or halts the growth of leukemic and other rapidly proliferating cells.

Leukin belongs to the purine analog antimetabolite (thiopurine) class of antineoplastic/immunosuppressant medicines.

Mercaptopurine is a prodrug that is inactive until metabolized intracellularly, mainly by hypoxanthine-guanine phosphoribosyltransferase (HGPRT), into active thioguanine nucleotides (TGNs). These active metabolites are incorporated into DNA and RNA, inhibiting purine synthesis and interfering with nucleic acid production, which blocks proliferation of leukemic cells and other rapidly dividing cells (cytotoxic/immunosuppressive effect).

Mercaptopurine is also metabolized by two competing enzyme pathways: thiopurine S-methyltransferase (TPMT) and nudix hydrolase 15 (NUDT15), which inactivate the drug. Patients with reduced or absent TPMT/NUDT15 enzyme activity (due to genetic polymorphisms) accumulate higher levels of active TGNs and are at significantly increased risk of severe, potentially life-threatening myelosuppression at standard doses. Genotype/phenotype testing for TPMT and NUDT15 is recommended before starting therapy where available, with dose adjustment in deficient patients.

Leukin tablets are taken orally, typically once daily, with or without food, at approximately the same time each day. Tablets should be swallowed whole; caregivers and patients handling Leukin (e.g., if a tablet must be split) should avoid direct skin contact and wash hands thoroughly, as it is a cytotoxic medicine. Do not change the dose, schedule, or stop the medicine without consulting the treating physician.

Allopurinol (major interaction)

Allopurinol (and other xanthine oxidase inhibitors) significantly inhibit the metabolism of Leukin, markedly increasing its blood levels and the risk of severe, potentially life-threatening myelosuppression. If concurrent use is unavoidable, the dose of Leukin must be reduced to approximately one-quarter to one-third of the usual dose, with close blood count monitoring.

Warfarin and other anticoagulants

Leukin may decrease the anticoagulant effect of warfarin; INR should be monitored more closely if used together.

Other myelosuppressive or hepatotoxic drugs

Concurrent use of other bone-marrow suppressing drugs (e.g., other chemotherapy agents, some antivirals) or hepatotoxic drugs may increase the risk of severe myelosuppression or liver injury; combinations should only be used under specialist supervision with enhanced monitoring.

Aminosalicylates (e.g., sulfasalazine, mesalamine, olsalazine)

These may inhibit TPMT activity and increase Leukin toxicity; use together cautiously with closer monitoring.

Live vaccines

Because Leukin is immunosuppressive, live/live-attenuated vaccines should generally be avoided during treatment due to risk of disseminated infection.

Side effects of Leukin are frequent and dose-related; regular monitoring by the treating physician is essential.

Very common

• Myelosuppression — anemia, leukopenia, and thrombocytopenia (low red cells, white cells, and platelets)

Common

• Loss of appetite, nausea, vomiting, diarrhea
• Mouth sores (stomatitis)
• General weakness/malaise, skin rash
• Elevated liver enzymes

Less common but serious

• Hepatotoxicity, including liver fibrosis or, rarely, liver failure
• Pancreatitis
• Increased susceptibility to infections due to immunosuppression
• Secondary cancers (e.g., lymphoma, skin cancers) with long-term use
• Hair thinning (alopecia), pulmonary fibrosis (rare)

Patients should seek prompt medical attention for fever, unusual bleeding/bruising, signs of infection, yellowing of the skin/eyes, or severe abdominal pain while taking Leukin.

Pregnancy: Leukin can cause fetal harm and is generally avoided during pregnancy, especially in the first trimester. It should be used during pregnancy only if clearly needed and if the potential benefit justifies the potential risk to the fetus, and only under close specialist supervision. Women of childbearing potential should use effective contraception during treatment and for a period after stopping, as advised by their physician.

Lactation: Leukin passes into breast milk. Breastfeeding is generally not recommended during treatment and for approximately one week after the last dose, due to potential risk to the infant. Discuss feeding options with the treating physician.

Myelosuppression

Leukin commonly causes dose-related bone marrow suppression. Complete blood counts must be monitored regularly (e.g., weekly initially), with dose adjustment or interruption for significant cytopenias.

TPMT/NUDT15 genetic testing

Individuals with reduced TPMT or NUDT15 enzyme activity are at markedly increased risk of severe, life-threatening toxicity at standard doses. Genotype/phenotype testing before or during early therapy is recommended where available, with dose reduction in deficient patients.

Hepatotoxicity

Liver function tests (transaminases, bilirubin, alkaline phosphatase) should be monitored regularly, as Leukin can cause liver injury, including fibrosis.

Secondary malignancy risk

Long-term use of Leukin carries a risk of secondary cancers, including lymphoma and skin cancers; sun protection and long-term follow-up are advised.

Immunosuppression and infection risk

Leukin increases susceptibility to infections; avoid live vaccines and report fever or signs of infection promptly.

Specialist supervision required

Leukin must only be prescribed and monitored by physicians experienced in cancer chemotherapy or immunosuppressive therapy, with regular laboratory monitoring throughout treatment.

Overdose of Leukin may cause severe bone marrow suppression, bleeding, infection, nausea, vomiting, diarrhea, and liver or gastrointestinal injury, which may be delayed in onset. If an overdose of Leukin is suspected, seek immediate medical attention or contact a poison control center/emergency services right away. Do not attempt to manage an overdose at home; hospital-based monitoring of blood counts and supportive care is typically required.

Store at room temperature (below 30°C), away from light and moisture. Keep out of reach of children.

Pediatric use

Leukin is an established treatment for acute lymphoblastic leukemia maintenance therapy in children, dosed on a weight (mg/kg) basis as part of combination chemotherapy, under pediatric oncology supervision. Young children may be more prone to certain effects (e.g., hypoglycemia has been reported in some young children); close monitoring is required.

Elderly

Elderly patients should generally start at the lower end of the dosing range, with closer monitoring of renal and hepatic function and blood counts, due to greater susceptibility to toxicity.

Renal impairment

Use the lowest recommended starting dose and monitor closely, as reduced clearance may increase toxicity risk.

Hepatic impairment

Use the lowest recommended starting dose and monitor liver function and blood counts closely, as Leukin can be hepatotoxic.

TPMT/NUDT15-deficient patients

Require substantial dose reduction and closer monitoring — see Precautions and Dosage sections.

Duration of Leukin therapy is determined by the treating specialist according to the treatment protocol. For acute lymphoblastic leukemia, maintenance therapy with Leukin typically continues for an extended period (often around two years) as part of the overall chemotherapy plan. For inflammatory bowel disease, duration is individualized based on response and tolerability. Treatment should not be stopped or extended without medical advice.

Antineoplastic agent; Immunosuppressant; Purine analog antimetabolite (thiopurine)

Mercaptopurine is a prodrug converted intracellularly into active thioguanine nucleotides, which are incorporated into DNA/RNA and inhibit de novo purine synthesis, blocking nucleic acid production in rapidly dividing cells. This produces cytotoxic effects on leukemic cells and immunosuppressive effects, forming the basis of its antileukemic and immunosuppressive activity.

Leukin is an established component of maintenance chemotherapy for acute lymphoblastic leukemia in children, dosed by body weight (approximately 1.5–2.5 mg/kg once daily) as part of a combination regimen, under pediatric oncology supervision with regular blood count monitoring. Safety and efficacy for other pediatric uses beyond established oncology protocols have not been established; such use requires specialist judgment.