Chlorambucil CAS 305-03-3 — China API Manufacturer | USP/EP/BP R&D to Production

Product Overview & China Manufacturing Landscape

Chlorambucil is a nitrogen mustard alkylating agent used as a first-line chemotherapeutic for chronic lymphocytic leukemia (CLL), and also employed in treating certain lymphomas, Waldenström macroglobulinemia, and advanced ovarian carcinoma. With CAS number 305-03-3 and molecular formula C₁₄H₁₉Cl₂NO₂, chlorambucil remains on the WHO Essential Medicines List as a critical oncology API. As a cytotoxic compound, manufacturing is restricted to facilities with appropriate containment infrastructure. China maintains approximately 5 NMPA-registered manufacturers qualified for chlorambucil production, with combined annual capacity of roughly 10-15 metric tons serving global demand. Our facility in Hubei Province is one of China’s leading cytotoxic API manufacturing platforms, with over 15 years of continuous production experience in nitrogen mustard chemistry.

Our Manufacturing Process & Facility Standards

Our chlorambucil synthesis follows a well-established route beginning with 4-aminophenylbutyric acid, proceeding through controlled bis-chloroethylation under precisely managed reaction conditions. The process requires careful temperature control throughout to minimize degradation and maximize yield. Manufacturing takes place in our dedicated cytotoxic production building featuring negative-pressure cascade design, isolator-based material transfers, and ISO 14644-1 Class 7 cleanroom environments for final processing. The facility includes OEB Level 4 containment throughout and OEB Level 5 zones for high-dust-generation operations such as milling and packaging. In-process controls include reaction completion monitoring by TLC and HPLC, pH control during crystallization, residual chloroethylamine precursor testing, and final particle size analysis. All equipment surfaces in contact with product are validated for cleanability to sub-microgram levels. Our production batch records show assay RSD below 1.0% across 90+ consecutive commercial batches, demonstrating reliable process control.

Quality Standards & Multi-Pharmacopeial Compliance

Our chlorambucil API is produced to simultaneously meet USP-NF, European Pharmacopoeia (EP 11.0), and British Pharmacopoeia (BP) standards. Typical assay values are 98.5-100.5% on a dried basis. Key quality parameters include: related substances by HPLC (each individual impurity ≤0.5%, total ≤1.5%), residual solvents per ICH Q3C with particular attention to chlorinated solvent control, loss on drying (≤0.5%), heavy metals (≤20 ppm), chloride content verification, and specific optical rotation. Given the mutagenic nature of nitrogen mustard compounds, we perform expanded genotoxic impurity testing per ICH M7 guidelines with limits set at TTC-based acceptable intakes. All QC operations for chlorambucil are conducted in contained analytical laboratories. Stability data per ICH Q1A confirms 36-month shelf life when stored at 2-8°C. Complete COA documentation with full impurity profiles accompanies every shipment.

Regulatory Documentation & Registration Support

Our chlorambucil regulatory dossier includes: NMPA drug registration certificate, US FDA Type II DMF, European ASMF, and current quality certificate with explicit cytotoxic API manufacturing scope. Our facility maintains FDA establishment registration and has been audited by multiple European qualified persons with satisfactory outcomes. We provide complete CTD Module 3.2.S documentation including detailed containment and cross-contamination control strategies — a critical regulatory focus area for cytotoxic APIs. Additional documentation includes ICH M7 genotoxic impurity risk assessment, cleaning validation reports with analytical methods capable of detecting chlorambucil at ng/cm² levels, and environmental monitoring data demonstrating effective containment. Our regulatory team supports customer filing activities with rapid document preparation, inspection readiness coordination, and technical response drafting for authority questions.

Packaging, Storage & Global Logistics

Chlorambucil API is packaged in double-sealed aluminum foil bags within HDPE containers, with desiccant and oxygen absorber sachets included. Standard packaging sizes are 100 g, 500 g, 1 kg, and 5 kg. All outer packaging features appropriate cytotoxic hazard labeling per GHS and transport regulations. Storage conditions require 2-8°C in a dry environment protected from light, with validated shelf life of 36 months. Shipments are coordinated via cold chain logistics with temperature monitoring throughout transit. Air freight is the standard shipping method for most destinations (3-7 days), with refrigerated sea freight available for larger volume orders to cost-sensitive markets (30-40 days). All shipments comply with IATA and IMDG dangerous goods regulations as applicable. Our logistics department prepares complete export documentation and coordinates with customer-nominated freight forwarders when required.

Competitive Pricing & Supply Reliability

Our established nitrogen mustard chemistry platform and dedicated cytotoxic manufacturing infrastructure provide cost efficiencies that translate to competitive competitive pricing. Compared to European cytotoxic API manufacturers, our pricing typically offers 30-45% savings for equivalent pharmacopeial grade material with comparable containment standards. MOQ is 100 g for qualification, with commercial orders from 500 g. We offer annual supply contracts with scheduled quarterly deliveries, fixed pricing for 12-month periods, and safety stock arrangements. Current production capacity supports up to 500 kg per month of chlorambucil API. We maintain strategic raw material inventory for 6+ months of continuous production. As an essential medicine API, chlorambucil production receives priority scheduling in our facility to ensure uninterrupted supply to customer base.

Product Specifications