TCS Industries Limited (China-sourced API supplier) supplies Tofacitinib Citrate — API CAS 540737-29-9 for pharmaceutical B2B procurement — COA, MSDS, and technical documentation available on request.
> Overview
| Product Name | Tofacitinib Citrate |
|---|---|
| Structural Formula |  |
| CAS Number | 540737-29-9 |
| Molecular Formula | C22H28N6O8 |
| Molecular Weight | 504.5 g/mol |
| InChIKey | SYIKUFDOYJFGBQ-YLAFAASESA-N |
| SMILES | Available on request where applicable |
| Appearance | White to off-white powder |
| Purity / Grade | By agreed specification and batch COA |
| Storage | Store at controlled room temperature, protect from moisture |
Tofacitinib Citrate (CAS 540737-29-9) is the citrate salt of tofacitinib, a selective Janus kinase (JAK) inhibitor. The free base has the formula C₁₆H₂₀N₆O (MW 312.37). Tofacitinib preferentially inhibits JAK1 and JAK3, blocking intracellular signaling of multiple cytokines involved in immune and inflammatory responses. It is used for rheumatoid arthritis, psoriatic arthritis, ulcerative colitis, and other autoimmune conditions.
TCS Industries Limited, a Hong Kong-based trading and sourcing company, supplies Tofacitinib Citrate API for global pharmaceutical procurement programs.
> Applications
JAK inhibitor for autoimmune diseases
Tofacitinib inhibits JAK1/JAK3 signaling, blocking downstream STAT phosphorylation and reducing production of pro-inflammatory cytokines (IL-2, IL-4, IL-6, IL-7, IL-15, IL-21, IFN-γ). It is administered orally at 5 mg twice daily for rheumatoid arthritis. Fleischmann et al. (N Engl J Med, 2012, 367:495–507) demonstrated significant ACR20 response improvement with tofacitinib versus placebo in methotrexate-inadequate-response RA patients.
Formulation and extended release
Tofacitinib citrate is formulated as immediate-release tablets (5 mg, 10 mg as free base) and extended-release tablets (11 mg as free base). The citrate salt form provides suitable crystallinity and stability for solid oral dosage forms. Extended-release formulations use osmotic pump technology to achieve once-daily dosing.
> Sourcing & Supply
TCS Industries Limited supports development, qualification and commercial purchasing discussions for Tofacitinib Citrate with buyers in Australia, New Zealand, Canada and South Korea.
- Evaluation and commercial quantities: 100 g samples for analytical qualification; 1 kg and 5 kg for formulation development; 25 kg drums for production. DMF reference letters available.
- Pallet quantities and production campaigns: repeat supply is coordinated against packaging, lead time, annual demand and destination-market import requirements.
> Quality & Documentation
Key specification parameters include assay (≥98.5%), related substances (individual ≤0.15%, total ≤0.5%), residual solvents, water content, particle size distribution, chiral purity (single enantiomer, R-configuration at C-3 piperidine), heavy metals, and microbial limits. White to off-white crystalline powder. Identity by HPLC, IR, and specific optical rotation. Meets in-house pharmaceutical specifications with reference to ICH guidelines. COA, MSDS, and DMF documentation are standard.
> Packaging
Tofacitinib citrate is a white to off-white powder, slightly hygroscopic. Standard packaging includes double PE-lined aluminium foil bags in fibre drums (1 kg, 5 kg, or 25 kg). Store at 2–8 °C or controlled room temperature per manufacturer specification. Protect from light and moisture. Shelf life is typically 24 months under recommended conditions. Labels and documents are checked before dispatch.
> Pricing & MOQ
Pricing is quoted by specification, packaging and destination. Common commercial discussions use 25 kg bag/drum formats, pallet quantities and production-campaign planning; smaller samples may be reviewed for qualified formulation teams.
> Regulatory & Compounding Context
Tofacitinib was FDA-approved in 2012 (Xeljanz) for rheumatoid arthritis, with subsequent approvals for psoriatic arthritis (2017), ulcerative colitis (2018), and ankylosing spondylitis (2022). EMA-authorized (2017). Listed as a specialty API. Generic tofacitinib products require ANDA with bioequivalence data. Pfizer patent expirations vary by jurisdiction. DMF support available from qualified manufacturers.
> Alias Index
- INN: Tofacitinib
- CAS Number: 540737-29-9 (citrate); 477600-75-2 (free base)
- Formula: C₁₆H₂₀N₆O · C₆H₈O₇ (MW 504.49, citrate)
- Brand name: Xeljanz (Pfizer)
- Pharmacological class: JAK inhibitor (JAK1/JAK3 selective)
- ATC code: L04AF01
- Commercial request terms: tofacitinib citrate API, JAK inhibitor bulk, Xeljanz generic, CP-690550 citrate, TCS Industries Limited
> FAQ
What is the JAK selectivity profile of Tofacitinib?
Tofacitinib preferentially inhibits JAK1 and JAK3 (IC50 ~1–3 nM), with lower activity against JAK2 (IC50 ~20 nM) and minimal TYK2 inhibition. JAK1/JAK3 selectivity targets the cytokine receptors most relevant to autoimmune pathology while partially sparing JAK2-dependent erythropoietin and thrombopoietin signaling.
What documents are available for Tofacitinib Citrate orders?
COA and MSDS are standard for commercial discussions. COO, packing list, invoice and other import-support documents can be arranged according to order scope.
Do you supply Tofacitinib Citrate to Australia and Canada?
Yes. We support B2B buyers in Australia, New Zealand, Canada and South Korea, subject to route and document review.
Do you supply New Zealand and South Korea?
Yes. We review Australia, New Zealand, Canada and South Korea for project supply, import documents, packaging and logistics planning before quotation.
Why is the Citrate salt form used?
The citrate salt provides superior crystallinity, stability, and reproducible dissolution compared to the free base. It has a defined melting point and is non-hygroscopic under normal storage. The citrate counterion does not affect pharmacological activity — tofacitinib is released as the free base upon dissolution in GI fluid.
Is a DMF available for Tofacitinib Citrate?
Yes. TCS sources tofacitinib citrate from manufacturers who maintain active Drug Master Files (DMFs) with the FDA and equivalent submissions (ASMF/CEP) with EMA. DMF reference letters are provided to support ANDA and generic marketing authorization applications.
Can you arrange samples before commercial purchasing?
Samples or evaluation quantities may be reviewed for qualified buyers after target specification, application and destination-market requirements are clarified.
How is Tofacitinib Citrate packaged for export?
Packaging is confirmed by quantity and material properties. Typical options include foil bags, HDPE containers, fibre drums, 25 kg bags or palletized export packaging.
Can buyer-defined specifications be reviewed?
Yes. Send the specification, methods, impurity limits and required documents. TCS can review feasibility before confirming quotation and lead time.
What payment terms are normally used?
Standard payment is 100% T/T before dispatch unless a different arrangement has been approved for an established commercial account.
What lead time should buyers expect?
Lead time depends on stock, batch size, document scope and destination. Available stock can move faster; made-to-order or pallet programs require longer planning.
What regulatory pathway applies to generic Tofacitinib?
Generic tofacitinib requires an ANDA (US) or Article 10 application (EU) with bioequivalence study data versus the reference product. Patent status varies by jurisdiction and salt form. Consult patent landscapes and paragraph IV certifications before filing. TCS provides regulatory support documentation from API manufacturers.
Last reviewed: June 2026
Evaluation and research orders (≤10 kg) are shipped with COA, MSDS, and certificate of origin. Bulk commercial orders (>10 kg) qualify for volume pricing with a full technical documentation package available on request.
> Request a Quote
If your team already has a target application, estimated quantity, destination market, or documentation requirements, send those details so the commercial response can be prepared more efficiently.