Raloxifene Hydrochloride

Inquiry

Cat Number

API0231575

CAS Number

82640-04-8

If you have any other questions, please contact our experts.

Product Detail Description Scientific Support Advanced Innovations Customer Q&A

CAS Number

82640-04-8

EINECS

639-789-7

Storage

Store at room temperature

Synonyms

Raloxifene HCl; Evista; Keoxifene hydrochloride; Optruma; Raloxifene Teva; LY156758

Molecular Formula

C28H28ClNO4S

Molecular Weight

510

Smiles

C1CCN(CC1)CCOC2=CC=C(C=C2)C(=O)C3=C(SC4=C3C=CC(=C4)O)C5=CC=C(C=C5)O.Cl

Appearance

White to light yellow crystalline powder

Melting Point

250-253℃

Boiling Point

728.2℃ at 760 mmHg

Relative Density

1.285

General Description

Raloxifene hydrochloride belongs to the class of selective estrogen receptor modulators (SERMs), offering mixed agonist and antagonist activity depending on the target tissue. It is structurally distinct from estrogen, designed to provide beneficial estrogenic effects on bone without stimulating breast or uterine tissue.

Mechanism of Action

This agent binds to estrogen receptors with high affinity, triggering tissue-specific transcriptional regulation. In bone, it acts as an estrogen agonist, reducing osteoclast activity and slowing bone resorption, which preserves bone mineral density. Conversely, in breast and endometrial tissues, raloxifene functions as an antagonist, blocking estrogen-driven cellular proliferation. This dual pharmacology underlies its therapeutic utility without the classic hormonal side effects.

Application

Raloxifene is indicated for the prevention and treatment of postmenopausal osteoporosis, significantly reducing vertebral fracture risk. It is also approved for lowering invasive breast cancer risk in postmenopausal women with osteoporosis or at high risk for the disease. Unlike bisphosphonates, it does not reduce non-vertebral fractures but offers the added benefit of favorable lipid effects.

A sensitive LC‑MS/MS method was developed and validated for simultaneous quantification of the selective estrogen receptor modulators levormeloxifene (L‑ORM) and raloxifene (RAL), using a Quality‑by‑Design optimized nanoemulsion. The method was linear from 1–600 ng/mL. Pharmacokinetic parameters in the nanoemulsion showed Cmax values of 65.07 ng/mL for L‑ORM and 59.27 ng/mL for RAL, compared with free drug values of 70.65 and 13.53 ng/mL, respectively. This method will support further development of L‑ORM and RAL nanoemulsions for postmenopausal osteoporosis and breast cancer.

Fig. 1 Typical multiple reaction monitoring chromatograms. (Chauhan D, et al., 2024)

References

Chauhan D, et al. Enhanced oral bioavailability of levormeloxifene and raloxifene by nanoemulsion: simultaneous bioanalysis using liquid chromatography-tandem mass spectrometry. Nanomedicine (Lond). 2024;19(12):1051-1068.

Using a Box‑Behnken design and phase inversion temperature method, raloxifene hydrochloride lipid nanocapsules were optimized and incorporated into a hydrogel. The optimized formulation had entrapment efficiency 79.6%, particle size 56.7 nm, and monodisperse nature. The hydrogel showed shear‑thinning properties, sustained drug release, and dermal compatibility. Compared to control, it achieved 2‑fold higher skin permeability and 3.4‑fold greater drug retention. This transdermal system overcomes the low oral bioavailability of raloxifene, offering a promising alternative for osteoporosis and breast cancer therapy.

Fig. 2 Characterization of OR-LNC. (Chaturvedi S, et al., 2025)

References

Chaturvedi S, et al. Development and optimization of raloxifene hydrochloride loaded lipid nanocapsule based hydrogel for transdermal delivery. Ther Deliv. 2025;16(2):139-154.

Does Raloxifene Hydrochloride require protection from light during long-term storage?

Yes, it is photosensitive. Exposure to UV light can cause photodegradation and yellowing. Store in light-resistant containers, preferably original opaque packaging.

What is the recommended storage temperature for Raloxifene Hydrochloride?

Store at controlled room temperature (15-25°C). Avoid temperatures above 30°C, which can accelerate oxidative degradation and impurity formation.

Is Raloxifene Hydrochloride hygroscopic, and how does this affect stability?

It exhibits low to moderate hygroscopicity. Under high humidity (>60% RH), it may absorb moisture and form a hydrate, altering dissolution properties. Store with desiccant.

How is the impurity raloxifene 6-glucuronide monitored during stability?

This potential degradation product is not typically monitored in API stability; however, we control for oxidative dimers using a validated HPLC method.