Armidex

Orals

Armidex

Armidex is a pharmaceutical tablet formulation of Anastrozole at 1 milligram per tablet. Anastrozole is a potent, selective, non-steroidal aromatase inhibitor (NSAI) — the first of the third-generation aromatase inhibitors to achieve regulatory approval. As a reversible, competitive aromatase inhibitor, anastrozole suppresses systemic estrogen biosynthesis with exceptional potency and selectivity, making it the reference standard against which other aromatase inhibitors are compared in clinical pharmacology.

Structural Profile and Classification

Anastrozole is a triazole-based non-steroidal compound. Unlike steroidal aromatase inhibitors (e.g., exemestane) that are structural analogues of the natural substrate, anastrozole acts by coordinating the triazole nitrogen atoms to the haem iron of the CYP19A1 active site, blocking substrate access through reversible competitive inhibition. This mechanism — competitive, reversible binding to the enzyme active site — classifies anastrozole as a Type II (non-steroidal) aromatase inhibitor. The binding is highly selective for CYP19A1 (aromatase) with minimal cross-inhibition of other cytochrome P450 enzymes at clinical concentrations.

Pharmacokinetic Profile

Anastrozole is rapidly and completely absorbed from the gastrointestinal tract with oral bioavailability approaching 100%. Peak plasma concentrations are achieved within 2 hours of administration. The plasma elimination half-life is characteristically long at 40–50 hours, producing stable steady-state plasma concentrations with once-daily dosing within 7 days. At steady state, a single 1 mg daily dose suppresses plasma estradiol by approximately 80–85% in postmenopausal women. Anastrozole is extensively metabolized by N-dealkylation, hydroxylation, and glucuronidation in the liver, with the primary metabolite triazole eliminated renally.

Mechanism of Aromatase Inhibition

Anastrozole competitively inhibits CYP19A1 by coordinate bonding of the triazole nitrogen to the enzyme active-site haem iron, preventing binding and oxidative processing of androgen substrates (androstenedione, testosterone). Inhibition is reversible — anastrozole dissociates from the enzyme upon clearance from plasma, restoring aromatase activity as circulating anastrozole declines. This reversibility means estrogen suppression is tightly correlated with plasma anastrozole concentration, providing predictable pharmacodynamic control. At the 1 mg clinical dose, anastrozole achieves >95% suppression of aromatase activity in breast tissue and peripheral adipose.

Formulation

Each Armidex tablet contains 1 mg Anastrozole IP as active ingredient, manufactured to Indian Pharmacopoeia specification under GMP-compliant conditions. Pharmaceutical excipients include lactose monohydrate, microcrystalline cellulose, sodium starch glycolate, and magnesium stearate. Batch release testing includes HPLC concentration verification (95–105% label claim), purity analysis (≥98%), dissolution testing, and complete microbiological limits evaluation prior to distribution. A Certificate of Analysis is issued for every production lot.

Quality Assurance

Every batch of Armidex produced by Biomedica undergoes the complete pharmaceutical release testing protocol before distribution. This includes HPLC compound identity confirmation and purity analysis (specification: ≥98%), concentration verification (specification: ±5% of label claim), sterility testing per USP <71>, bacterial endotoxin quantification by LAL assay (specification: <0.25 EU/mL), and particulate matter inspection per USP <788>. A Certificate of Analysis is issued for every production lot.

Authentication

Each unit of Armidex carries a unique authentication code on its outer packaging. This code can be verified instantly on our Authentication page to confirm the product is genuine Biomedica stock.