Acetazolamide CAS 59-66-5 — China API Manufacturer | ChP/USP/EP R&D to Production

Product Overview & China Manufacturing Landscape

Acetazolamide is a carbonic anhydrase inhibitor widely prescribed for glaucoma, altitude sickness, epilepsy, and idiopathic intracranial hypertension. With CAS number 59-66-5 and molecular formula C₄H₆N₄O₃S₂, this sulfonamide derivative remains a cornerstone in multiple therapeutic categories. China has established itself as the dominant global manufacturing base for acetazolamide API, with over 15 NMPA-registered manufacturers operating dedicated production lines. National annual production capacity exceeds 800 metric tons, supplying finished dosage form manufacturers across Asia, Europe, Latin America, and Africa. Our facility is strategically located in Zhejiang Province, one of China’s premier pharmaceutical manufacturing clusters, giving us access to integrated raw material supply chains and specialized chemical engineering talent.

Our Manufacturing Process & Facility Standards

Our acetazolamide synthesis follows a well-established multi-step route starting from 5-amino-1,3,4-thiadiazole-2-sulfonamide, employing controlled acetylation under optimized reaction conditions. The entire manufacturing process takes place within our quality-certified workshop spanning 12,000 square meters, featuring ISO 14644-1 Class 7 (Class 10,000) cleanroom environments for final crystallization and drying stages. In-process quality controls include real-time HPLC monitoring at each synthetic step, pH and temperature logging with automated deviation alerts, and intermediate purity gates that must reach ≥97.5% before advancing to subsequent stages. Our batch-to-batch consistency data demonstrates relative standard deviation (RSD) below 1.2% for assay values across the last 120 consecutive production batches. Each production cycle yields 500-800 kg of finished API, with a typical campaign duration of 12-15 days from raw material charging to final release.

Quality Standards & Multi-Pharmacopeial Compliance

Our acetazolamide API is manufactured to simultaneously comply with Chinese Pharmacopoeia (ChP 2020), United States Pharmacopeia (USP-NF), European Pharmacopoeia (EP 11.0), and Japanese Pharmacopoeia (JP XVIII) standards. Typical assay values reach 99.5-100.2% on a dried basis, well within all pharmacopeial requirements. Key controlled parameters include residual solvents (ICH Q3C compliant), heavy metals (≤10 ppm by ICP-MS), related substances (total impurities ≤0.5% by HPLC), and loss on drying (≤0.5%). Every shipment is accompanied by a complete Certificate of Analysis (COA) reflecting the specific pharmacopeial standard requested by the customer. We also provide full method validation packages and reference standard comparison data upon request. Our QC laboratory operates 12 HPLC systems, 4 GC units, ICP-MS, KF titrators, and particle size analyzers to ensure complete analytical coverage.

Regulatory Documentation & Registration Support

We maintain a complete regulatory dossier for acetazolamide API that supports customer registrations worldwide. Available documentation includes: an active Chinese Drug Master File (DMF) filed with NMPA, a US FDA DMF (Type II) with current annual updates, European CEP/COS certification through EDQM, current quality certificate issued by provincial drug administration authority, and FDA establishment registration for our manufacturing site. Our regulatory affairs team provides dedicated support for customers pursuing local market authorizations, including preparation of Module 3.2.S documentation in CTD format, response to deficiency letters from regulatory authorities, and coordination of on-site inspections by foreign regulatory bodies. We have successfully hosted inspections from EU QPs, ANVISA (Brazil), COFEPRIS (Mexico), and multiple ASEAN national authorities.

Packaging, Storage & Global Logistics

Acetazolamide API is packaged in pharmaceutical-grade double-layer polyethylene bags placed inside sealed aluminum drums. Standard packaging configurations include 1 kg/bag, 5 kg/bag, and 25 kg/drum options, with custom packaging available for orders above 500 kg. All packaging materials comply with FDA 21 CFR and EU Regulation 10/2011 for pharmaceutical contact materials. Storage conditions require a cool, dry environment below 25°C, protected from light, with a validated shelf life of 36 months under recommended conditions. We ship via major international freight forwarders with temperature-monitored containers when required. Typical lead times to European ports are 28-35 days by sea freight, 12-15 days by rail to Central Europe, and 5-7 days by air freight. All export documentation including commercial invoice, packing list, COA, and phytosanitary certificates are prepared by our dedicated logistics department.

Competitive Pricing & Supply Reliability

As a vertically integrated Chinese manufacturer, we offer significant cost advantages through direct competitive pricing without intermediary markups. Our production scale allows us to maintain competitive per-kilogram pricing that typically represents 30-45% savings compared to European or Indian API sources for equivalent pharmacopeial grade material. Minimum order quantity starts at 25 kg for initial qualification orders, with standard commercial orders from 100 kg upward. We provide transparent pricing structures with volume-based tiering and welcome long-term supply agreements with fixed or index-linked pricing for 12-24 month periods. Our current raw material inventory supports continuous production for 6+ months, eliminating supply disruption risks. We maintain safety stock equivalent to 2-3 months of each key customer’s forecast demand, ensuring rapid order fulfillment even during peak demand periods.

Product Specifications