TCS Industries Limited (China-sourced API supplier) supplies Fulvestrant — API CAS 129453-61-8 for pharmaceutical B2B procurement — COA, MSDS, and technical documentation available on request.
> Overview
| Product Name | Fulvestrant |
|---|---|
| Structural Formula |  |
| CAS Number | 129453-61-8 |
| Molecular Formula | C32H47F5O3S |
| Molecular Weight | 606.8 g/mol |
| InChIKey | VWUXBMIQPBEWFH-WCCTWKNTSA-N |
| SMILES | Available on request where applicable |
| Appearance | White to off-white powder |
| Purity / Grade | By agreed specification and batch COA |
| Storage | 2–8°C |
Fulvestrant (CAS 129453-61-8) is a selective estrogen receptor degrader (SERD) with the formula C₃₂H₄₇F₅O₃S (MW 606.77). Unlike tamoxifen (a SERM that partially activates the ER), fulvestrant binds, blocks, and degrades the estrogen receptor, providing pure estrogen antagonism. It is used for hormone receptor-positive metastatic breast cancer.
TCS Industries Limited, a Hong Kong-based trading and sourcing company, supplies Fulvestrant API in pharmaceutical grade for global procurement programs.
> Applications
ER-positive metastatic breast cancer
Fulvestrant 500 mg IM on days 1, 15, 29, then monthly is used for hormone receptor-positive metastatic breast cancer in postmenopausal women, either as monotherapy or combined with CDK4/6 inhibitors (palbociclib, ribociclib, abemaciclib). It degrades the ER through proteasomal pathway, achieving >95% ER downregulation. Robertson et al. (Cancer Res, 2001, 61:6739–6746) characterized the mechanism of fulvestrant as the first pure antiestrogen and selective estrogen receptor degrader in clinical development for breast cancer.
Combination with CDK4/6 inhibitors
Fulvestrant + CDK4/6 inhibitor is a standard first- or second-line endocrine therapy for advanced ER+/HER2- breast cancer. The PALOMA-3 trial established fulvestrant + palbociclib as superior to fulvestrant alone in endocrine-pretreated patients. Oral SERD development is ongoing to replace the injection formulation.
> Sourcing & Supply
TCS Industries Limited supports development, qualification and commercial purchasing discussions for Fulvestrant with buyers in Australia, New Zealand, Canada and South Korea.
- Evaluation and commercial quantities: 50 g samples for analytical qualification; 500 g and 1 kg for production. Pharmaceutical-grade crystalline powder. 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 (≥97.0%), related substances, specific optical rotation, water content, residual solvents, heavy metals, and microbial limits. White crystalline powder. Practically insoluble in water, soluble in ethanol and DMSO. Contains five fluorine atoms. Identity by HPLC and IR. Meets in-house pharmaceutical specifications. COA, MSDS, and stability data are standard.
> Packaging
Fulvestrant is a white crystalline powder. Standard packaging includes sealed aluminium foil bags under nitrogen in fibre drums (50 g, 100 g, 500 g, or 1 kg). Store at 2–8 °C. Protect from light. Shelf life is typically 36 months at 2–8 °C. 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
Fulvestrant was FDA-approved in 2002 (Faslodex, AstraZeneca) at 250 mg monthly, with dose increase to 500 mg approved in 2010 based on the CONFIRM trial. EMA-authorized. Generic fulvestrant injection approved (2019, US). DMF support available from qualified manufacturers.
> Alias Index
- INN: Fulvestrant
- CAS Number: 129453-61-8
- Formula: C₃₂H₄₇F₅O₃S (MW 606.77)
- Brand name: Faslodex (AstraZeneca)
- ATC code: L02BA03
- Pharmacological class: SERD (selective estrogen receptor degrader)
- Commercial request terms: fulvestrant API, Faslodex generic, SERD API, ER degrader, breast cancer endocrine API, TCS Industries Limited
> FAQ
How does Fulvestrant differ from Tamoxifen?
Tamoxifen (SERM) blocks ER but retains partial agonist activity (endometrial stimulation, bone protection). Fulvestrant (SERD) binds, blocks, and degrades the ER protein — no residual ER signaling. This pure antagonism overcomes tamoxifen resistance driven by ER co-activator recruitment. Fulvestrant has no endometrial stimulation risk.
What documents are available for Fulvestrant 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 Fulvestrant 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 Fulvestrant given by injection?
Fulvestrant has very low oral bioavailability (<2%) due to extensive first-pass hepatic metabolism. The IM injection (250 mg/mL in castor oil/ethanol/benzyl alcohol) provides sustained-release depot delivery over the monthly dosing interval. Development of oral SERDs (elacestrant, imlunestrant) aims to overcome this limitation.
What is the 500 mg dosing rationale?
The CONFIRM trial showed that fulvestrant 500 mg monthly significantly improved progression-free survival versus 250 mg monthly. The higher dose achieves more complete ER downregulation. The loading schedule (500 mg on days 1, 15, 29, then monthly) rapidly achieves steady-state concentrations. Two 5 mL injections (one per gluteal) are given per visit.
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 Fulvestrant 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.
Is a DMF available?
Yes. TCS sources fulvestrant from manufacturers who maintain active DMFs with the FDA and equivalent regulatory submissions. Generic fulvestrant injection has been approved in the US. COA, stability data, and DMF reference letters are provided for generic formulation development.
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.