Raloxifene Hydrochloride is a selective estrogen receptor modulator (SERM) used as an active pharmaceutical ingredient in medicines for postmenopausal osteoporosis and related estrogen-receptor-mediated applications. The API is the hydrochloride salt of raloxifene and is identified by CAS 82640-04-8.
Raloxifene Hydrochloride has the molecular formula C₂₈H₂₇NO₄S·HCl and molecular weight 510.04 g/mol. The substance is achiral and has no defined stereocenters.
Raloxifene Hydrochloride is a benzothiophene-derived selective estrogen receptor modulator. It exhibits estrogen-like effects on bone while acting as an estrogen antagonist in certain tissues, including breast tissue.
The pharmaceutical API is controlled for identity, assay, related substances, loss on drying, residue on ignition and heavy metals under the USP monograph.
| Parameter | Details |
|---|---|
| Product | Raloxifene Hydrochloride |
| CAS | 82640-04-8 |
| Formula | C₂₈H₂₇NO₄S·HCl |
| Molecular Weight | 510.04 g/mol |
| Free Base CAS | 84449-90-1 |
| FDA UNII | 4F86W47BR6 |
| Pharmacological Class | SERM |
| Therapeutic Area | Osteoporosis / Women's Health |
| Physical Form | Powder/crystalline solid |
| Stereochemistry | Achiral |
| Pharmacopoeial Standard | USP |
Raloxifene Hydrochloride API is used in pharmaceutical development for:
The current USP monograph provides a defined analytical framework for Raloxifene Hydrochloride.
The API contains 97.5–102.0% raloxifene hydrochloride calculated on the dried basis. The USP assay uses liquid chromatography with UV detection at 280 nm.
USP also specifies:
Manufacturing of Raloxifene Hydrochloride requires controlled synthesis, purification and salt formation followed by validated analytical testing. Critical quality attributes include assay, related substances, residue on ignition, loss on drying and elemental/heavy-metal control.
USP specifies that Raloxifene Hydrochloride should be preserved in well-closed containers and stored at room temperature.
Typical documentation includes:
Raloxifene Hydrochloride benefits from a defined USP API specification covering assay, impurities, loss on drying, residue on ignition and heavy metals. Pharmaceutical manufacturing should therefore follow validated analytical procedures and maintain consistent batch-to-batch compliance with the applicable API specification.
| Parameter | Specification |
|---|---|
| Appearance | white to off-white crystalline powder |
| Identification | IR & HPLC compliant |
| Assay (HPLC) | 97.5–102.0% |
| Loss on Drying | NMT 0.5% |
| Residue on Ignition | NMT 0.10% |
| Heavy Metals | NMT 10 ppm |
| Individual Impurity | NMT 0.10% |
| Total Impurities | NMT 0.50% |