Mercaptopurine (6-MP) is used with other chemotherapy to maintain remission in acute lymphoblastic leukemia (ALL). Check product and country.
- Check the exact product.
- Follow urgent safety instructions.
- Funding disclosure does not establish independent efficacy.
Table of contents
- Evidence summary
- What it is and licensed uses
- How it works
- Care boundaries
- Supplements and supportive care
- Evidence limits
- Risks and urgent symptoms
- Interactions
- Pregnancy and breastfeeding
- Taking it safely
- Animal and laboratory evidence
- Funding: follow the money
- Frequently asked questions
- Sources and funding notes
Evidence summary
Independent comparative efficacy is unestablished here.
| Question | Source role | Limits |
|---|---|---|
| Food/dairy | 2017 cohort | Observational; liquid excluded; author commercial ties. |
| Use frequency | England items | Not patients, cancer-only use or global popularity. |
What it is and licensed uses
| Selected product | Licence |
|---|---|
| UK Aspen 50 mg tablet | ALL; acute promyelocytic leukaemia (APL/AML M3). |
| UK Xaluprine 20 mg/ml | ALL only. |
| US Purixan 20 mg/ml | Combination ALL maintenance. |
| US Florida 50 mg tablet | Combination ALL maintenance. |
Purinethol/Puri-Nethol: mercaptopurine names; stock unverified.
Mercaptopurine differs from azathioprine, thioguanine and its metabolites.
How it works
It interferes with purine metabolism needed for cell growth.
Care boundaries
Maintenance supports remission within combination ALL care. Overview. Read the separate ALL and AML guides.
Supplements and supportive care
Show supplements to the team; interactions are possible. No replacement is independently established here. Safety context.
Ask for a practical symptom and contact plan. Report barriers to taking prescribed treatment; request help adapting the routine.
Evidence limits
The 2017 cohort studied 441 TPMT-wild-type ALL patients. Liquids were excluded; NUDT15 and minimal residual disease were unavailable. Observational findings cannot establish equivalence or override labels.
Public/charity support coexisted with compensated author pharmaceutical ties. Outcomes are excluded from the independent verdict. Disclosures.
Risks and urgent symptoms
Jaundice means yellowing of skin or eye whites.
UK jaundice: stop immediately; urgent care. Blood/liver checks despite TPMT/NUDT15 enzyme/gene tests. Fever, bleeding, severe abdominal pain/swollen face: hospital immediately.
US: blood/liver monitoring despite TPMT/NUDT15 enzyme/gene tests. Fever, bleeding or severe abdominal pain: urgent assessment. Clinicians withhold for hepatotoxicity. Tablet; liquid.
Unlicensed UK inflammatory bowel disease (IBD): pancreatitis/rare aggressive lymphoma.
US: secondary cancers; sun protection. Tablet; liquid.
Interactions
UK: allopurinol requires clinician dose adjustment; febuxostat avoidance. Have medicines/vaccines reviewed.
US: allopurinol requires clinician dose adjustment; team review of all medicines/vaccines. Liquid; tablet.
Pregnancy and breastfeeding
| Product | Contraception / breastfeeding |
|---|---|
| UK tablet | During treatment/at least three months after; no breastfeeding. |
| UK liquid | Contraception during treatment; women six months after/men three. No breastfeeding. |
| US products | Contraception during treatment; women six months after/men three. No breastfeeding during/one week after; tablet. |
Discuss pregnancy, allergies and excipients before treatment. Leaflet.
Taking it safely
| Product/context | Instructions |
|---|---|
| UK products | Take medicine at least one hour before or two hours after milk/dairy; consistent food routine. |
| US products | Consistent food routine; tablet. No specific milk-spacing instruction. |
| CUH paediatric IBD | 2024 leaflet allows milk in unlicensed use; prescriber resolves discrepancies. |
Purixan: shake 30 seconds; supplied syringe; discard after eight weeks open. Instructions.
UK tablets: no home crushing/splitting/doubling. Overdose: hospital urgently.
Follow cytotoxic handling/disposal instructions; protect children. Pregnant carers avoid handling. Leaflet.
Animal and laboratory evidence
Preclinical hazards cannot prove benefit.
Funding: follow the money
Research funding at a glance
30 disclosure entries. The counts below summarize independence tiers explicitly assigned in this article. They count disclosures, not studies, funding amounts or evidence quality.
Consult this article’s source and funding notes for named funders, countries, relationships and exceptions where available. Institutional backing, researcher interests and trial sponsorship are separate questions. Public funding alone does not establish independence; commercial ties alone do not prove a claim false. This overview is not a new financial audit.
Revenue cannot establish study funding.
Verified business and financing routes
| Business route / country | Owners and backing |
|---|---|
| Aspen group (South Africa) | 30 June 2026: beneficial holdings (unaudited): GEPF/PIC 19.3%; Stephen Saad 13.2%; Gus Attridge family 4.3%. Aspen Pharma Trading is a group company; exact stake unclosed. |
| Nova Bio-Pharma Holdings Limited (UK) → 100% Nova Laboratories Limited | 8 May 2026 register: Peter White 14.55%, Regina White 45.45%; trustees: Peter White Family Trust No. 1 10%, Peter White Family Trust No. 2 30%. |
| Nova ← HSBC UK | Lab / parent secured creditor. |
| Indoco (India) → 85% FPP Holding Company LLC (US) → 100% Florida Pharmaceutical Products LLC | 31 March 2026: Kare promoters 58.86%; Citibank finances FPP Holding Company LLC. Other 15% owner unclosed. |
| Aarti Drugs (India) → wholly owned Pinnacle Life Science Private Limited | 31 March 2026: promoters 55.03%; group creditors Kotak Mahindra, Axis, HSBC. Manufacturing differs from Florida ownership. |
| Rare Disease Therapeutics (RDT; US) | Privately held; CEO Caroline Ellis Durst; founder Milton Ellis. No verified Nova equity link. |
| 2017 ingestion cohort ← public/charity support | NCI/NIGMS, COG, St Baldrick’s, ALSAC. Landier: Merck institutional research; Mascarenhas: Bayer/Lilly/AstraZeneca/MedImmune ties. Ultimate donors unclosed. |
Historical accounts; ultimate ownership unverified. Trust control/Nova Nominees’ appointment rights: non-additive. Register.
Payments, ultimate owners/donors and allocations remain unverified.
Source credibility: incentives and possible bias
| Source | Country / jurisdiction | Funding / ownership | Tier | Credibility / possible bias |
|---|---|---|---|---|
| UK tablet SmPC | Ireland / UK | Aspen Pharma Trading Limited; sales. | Tier 4 | D. Regulatory accuracy; possible sales bias. |
| UK tablet leaflet | Ireland / Germany | Aspen; EXCELLA/Bad Oldesloe. | Tier 4 | D. Safety duties; possible sales bias. |
| Xaluprine SmPC | UK | Nova; sales. | Tier 4 | D. Regulatory accuracy; possible sales bias. |
| Xaluprine leaflet | UK | Nova; sales. | Tier 4 | D. Safety duties; possible sales bias. |
| Purixan label | UK / US | Nova; manufactured for RDT. | Tier 4 | D. Label duties; possible sales bias. |
| Florida tablet label | US / India | Florida; Pinnacle manufacture. | Tier 4 | D. Label duties; possible sales bias. |
| NCI mercaptopurine overview | Bethesda, US | Congressional appropriation and Gift Fund; page payments unclosed. | Tier 2 | B provisional. Public accountability; possible institutional framing. |
| NCI drug dictionary | Bethesda, US | Congressional appropriation and Gift Fund; page payments unclosed. | Tier 2 | B provisional. Public accountability; possible institutional framing. |
| NCI budget | Bethesda, US | Congressional appropriation; institutional finance. | Tier 2 | B provisional. Budget accountability; possible political framing. |
| NCI Gift Fund | Bethesda, US | Private gifts permitted; donor allocations unclosed. | Tier 2 | B provisional. Public disclosure; possible donor emphasis. |
| CUH paediatric IBD leaflet | Cambridge, UK | NHS, research and commercial routes; leaflet payments unclosed. | Tier 2 | B provisional. Patient safety accountability; possible local-practice bias. |
| CUH 2025/26 accounts | Cambridge, UK | Public care, education/research, donations, private services; industry partnerships. | Tier 2 | B provisional. Reporting duties; possible institutional presentation. |
| Landier 2017 original | US authors; US/Canada/Australia sites | NCI/NIGMS, COG, St Baldrick’s, ALSAC; author pharma ties. | Tier 2 | C. Methods/disclosures permit scrutiny; possible career/commercial influence. |
| Aspen FY2026 accounts | South Africa; Ireland/Germany operations | Medicine/manufacturing revenue, equity, bank/DFI borrowing. | Tier 4 | D. Audited reporting duties; possible corporate presentation. |
| Indoco FY2025/26 report | Mumbai, India; US subsidiaries | Medicine sales, Kare promoter group, equity and bank finance. | Tier 4 | D. Listed reporting duties; possible corporate presentation. |
| Aarti FY2025/26 report | India | Medicine/API sales, promoter group and bank finance. | Tier 4 | D. Listed reporting duties; possible corporate presentation. |
| Nova Labs accounts | UK | Sales; HSBC UK. | Tier 4 | D. Audit duties; possible corporate bias. |
| Nova parent accounts | UK | Private group; HSBC UK. | Tier 4 | D. Audit duties; possible corporate bias. |
| Nova shareholder return | UK | Family/trust holdings. | Tier 4 | D. Filing duties; possible selective disclosure. |
| Nova control register | UK | Funding unverified. | Tier 2 | B provisional. Filing duties; possible reporting bias. |
| Nova Labs charges | UK | HSBC UK secured creditor; registrar finance unclosed. | Tier 2 | B provisional. Legal filing duties; possible selective disclosure. |
| Nova parent charges | UK | HSBC UK secured creditor; registrar finance unclosed. | Tier 2 | B provisional. Legal filing duties; possible reporting bias. |
| RDT company homepage | Franklin, Tennessee, US | Privately held commercial pharmaceutical company; equity/lenders unclosed. | Tier 4 | D. Business identity accountability; possible promotion bias. |
| RDT leadership page | Franklin, Tennessee, US | Commercial company; leadership is not equity proof. | Tier 4 | D. Reputational accountability; possible promotion bias. |
| England PCA workbook | Newcastle, UK; England data | NHSBSA public/service routes; dataset payment allocation unclosed. | Tier 2 | B provisional. Reproducible statistics; possible coding/coverage bias. |
| PCA methodology | UK; England data | NHSBSA; public/service routes. | Tier 2 | B provisional. Published definitions; possible coverage bias. |
| NHSBSA accounts | Newcastle, UK | DHSC/public finance, service fees and repayment routes. | Tier 2 | B provisional. Reporting accountability; possible institutional presentation. |
| NCCIH supplement safety | Bethesda, US | Public appropriations; private gifts possible; underlying trials unclosed. | Tier 2 | B provisional. Public safety reputation; possible institutional framing. |
| NCCIH appropriation history | Bethesda, US | Congressional appropriations; dated through FY2024. | Tier 2 | B provisional. Budget disclosure; possible political framing. |
| NCCIH donation authority | Bethesda, US | Private Gift Fund authority; named donors/allocations unclosed. | Tier 2 | B provisional. Public disclosure; possible donor emphasis. |
Frequently asked questions
What is 6-MP?
Mercaptopurine’s abbreviation. Nomenclature.
Who makes the selected US tablet?
Pinnacle Life Science Pvt Ltd manufactures it for Florida Pharmaceutical Products LLC.
Switch formulations?
UK switches need closer blood monitoring: peak exposure differs.
Do England items show global popularity?
No. They count community prescription items, not people, cancer-only use or worldwide use.
Is the study independent advice?
No: observational, no liquids, author commercial ties. Original.
Sources and funding notes
England 2025/26 recorded 50,759 mercaptopurine-coded community items, including 280 capsule items. Capsule/other-strength licences are unverified here; coding class does not establish compounding or unlicensed status. Workbook.
Dispensed prescription items are not patients or cancer-only use; hospital-pharmacy dispensing is excluded. Methods. No global popularity ranking.
- UK tablet SmPC — December 2024; full.
- UK tablet leaflet — December 2024; full.
- Xaluprine SmPC — February 2025; full.
- Xaluprine leaflet — February 2025; full.
- Purixan label — July 2026; full label/IFU.
- Florida tablet label — January 2026; full.
- NCI mercaptopurine overview — 25 July 2018; nomenclature and ALL maintenance, not current stock.
- NCI drug dictionary — Current dictionary: names and mechanism; not product availability or licensing.
- NCI budget — 14 May 2026; complete page; enacted/request distinctions.
- NCI Gift Fund — 27 August 2025; complete page, not a named page sponsor.
- CUH paediatric IBD leaflet — 2024 version 5; selected actual IBD guidance.
- CUH 2025/26 accounts — Selected research section and income notes; no complete 197-page audit.
- Landier 2017 original — Full original HTML, all eight images and 18 disclosures; excluded from independent outcome verdict.
- Aspen FY2026 accounts — 2 October 2026; selected audited notes; shareholder tables unaudited.
- Indoco FY2025/26 report — Selected actual subsidiary, ownership and Citi facility notes; 31 March 2026.
- Aarti FY2025/26 report — Selected actual ownership and consolidated debt notes; 31 March 2026.
- Nova Labs accounts — March 2025; selected.
- Nova parent accounts — Selected March 2025/later events.
- Nova shareholder return — 8 May 2026; full.
- Nova control register — Current full register.
- Nova Labs charges — Full current register: one outstanding charge; not a debt balance.
- Nova parent charges — Full current original; one outstanding charge; not ownership.
- RDT company homepage — Complete current original; self-description, not a cap-table audit.
- RDT leadership page — Complete current original; Caroline Ellis Durst CEO; Milton Ellis founder.
- England PCA workbook — Original chemical and all 16 presentation rows personally checked.
- PCA methodology — June 2026 complete methodology; items exclude hospital-pharmacy dispensing.
- NHSBSA accounts — Selected actual pages 12,132–134; no complete audit or PCA payment clearance.
- NCCIH supplement safety — Current selected safety guidance; no supplement efficacy ranking.
- NCCIH appropriation history — Complete actual page; not a FY2026 allocation.
- NCCIH donation authority — Complete actual page; not proof of a named source sponsor.
Educational research reviewed 5 October 2026. Clinical guidance covers selected UK/US products. Follow the exact medicine leaflet and urgent clinician instructions. Diagnosis and treatment require a qualified clinician.
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