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Product Name: Macitentan
Chemical Name: N-[5-(4-Bromophenyl)-6-[2-[(5-bromo-2-pyrimidinyl)oxy]ethoxy]-4-pyrimidinyl]-N'-propylsulfamide
Synonyms: Opsumit
CAS Number: 441798-33-0
Recommended Use: Treatment of pulmonary arterial hypertension
Manufacturer: Janssen Pharmaceuticals
Contact Information: Emergency contact available through local poison control and the company
Emergency Number: Provided by regional health services and manufacturer
Classification: Harmful if swallowed, suspected of damaging fertility or the unborn child, causes skin and serious eye irritation, may cause respiratory irritation
Label Elements: Skulls and crossbones for acute toxicity, exclamation mark for irritant, health hazard pictogram
Signal Word: Warning
Hazard Statements: H302: Harmful if swallowed, H315: Causes skin irritation, H319: Causes serious eye irritation, H335: May cause respiratory irritation, H361: Suspected of damaging fertility or the unborn child
Precautionary Statements: Avoid breathing dust/fume/gas/mist/vapors/spray, Wash hands thoroughly after handling, Use only outdoors or in a well-ventilated area, Wear protective gloves/eye protection/face protection
Other Hazards: Not flammable but dust may form explosive mixture in air, Limited environmental hazard data
Main Ingredient: Macitentan
Chemical Formula: C19H20Br2N6O4S
Purity: >98% on dry basis
Impurities: Not exceeding standard pharmacopeia thresholds
Formulation Components: May contain excipients in tablet form; consult pharmaceutical label for specific inactive ingredients
Concentration: Typically supplied as 10 mg per tablet for commercial use
Dangerous Components: With the exception of the active compound, no major hazardous impurities reported in production-strength tablets
Inhalation: Move patient to fresh air, provide artificial respiration if breathing stops, seek immediate medical attention
Skin Contact: Remove contaminated clothing, wash skin thoroughly with soap and water, seek medical advice if irritation persists
Eye Contact: Rinse cautiously with water for several minutes, remove contact lenses if present and easy to do, continue rinsing, seek medical advice
Ingestion: Rinse mouth, do not induce vomiting, never give anything by mouth to an unconscious person, get medical help promptly
Most Important Symptoms: May include irritation of mucous membranes, drowsiness, headache, nausea
Notes for Doctor: Symptomatic treatment required, check hepatic function regularly if exposure suspected
Suitable Extinguishing Media: Water spray, dry powder, foam, carbon dioxide
Unsuitable Extinguishing Media: High pressure water stream can spread powder
Hazards Arising from Combustion Products: Carbon monoxide, carbon dioxide, nitrogen oxides, sulfur oxides, hydrogen bromide
Protective Equipment for Firefighters: Wear tightly sealed self-contained breathing apparatus, full protective gear
Specific Hazards: Thermal decomposition can release hazardous fumes, powder dispersion may cause dust explosion risk in confined areas
Personal Precautions: Evacuate unnecessary personnel, avoid contact with dust, wear appropriate personal protective equipment including masks and gloves
Environmental Precautions: Prevent further leakage or spillage if safe to do so, avoid discharge into drains, soil, or waterways
Clean Up Methods: Collect spilled material by gentle sweeping or vacuum with HEPA filter, place in suitable waste container, ventilate area
Decontamination: Wash surface with water and detergent, dispose of contaminated materials according to regulations
Handling: Avoid inhalation of dust and contact with skin or eyes, use only in well-ventilated areas, do not eat or drink while handling, practice good industrial hygiene
Storage: Store tightly closed in original container, keep container in a cool, dry, well-ventilated area, protect from light, incompatible with strong oxidizers and acids
Special Storage Requirements: Store locked up, keep out of reach of unauthorized persons
Incompatible Materials: Strong bases, acids, oxidizing agents
Engineering Controls: Use in closed systems or local exhaust ventilation to limit airborne dust
Exposure Limit Values: No specific occupational exposure limits established; minimize exposure as much as possible per ALARA principle
Personal Protective Equipment: Gloves (nitrile or latex), eye protection (safety goggles), laboratory coats
Respiratory Protection: If dust formation likely, use NIOSH/MSHA approved respiratory protection
Hygiene Measures: Remove contaminated clothing, wash hands and face thoroughly after handling, do not take work clothing home
Appearance: White or off-white crystalline powder
Odor: No significant odor
Odor Threshold: Not determined
pH: Not applicable (insoluble in water)
Melting Point/Range: 229–233°C
Boiling Point/Range: Decomposes before boiling
Flash Point: Not flammable under normal conditions
Solubility: Poorly soluble in water, soluble in DMSO, DMF, methanol
Vapor Pressure: Negligible
Density: Approximately 1.5 g/cm³
Partition Coefficient (log P): 3.37
Decomposition Temperature: 240°C (approximate, releases toxic fumes)
Chemical Stability: Stable under recommended storage conditions
Possible Hazardous Reactions: Reacts with strong oxidants and acids; dust may create explosion hazard under certain conditions
Conditions to Avoid: Excessive moisture, direct sunlight, heat sources, open flames
Materials to Avoid: Strong oxidizing agents, strong acids and bases
Hazardous Decomposition Products: Oxides of carbon, nitrogen, sulfur, hydrogen bromide gas formed during breakdown
Acute Toxicity: Oral LD50 in rodents estimated between 500 and 2000 mg/kg, based on animal studies
Chronic Toxicity: Adverse effects on liver and reproductive system at high or prolonged exposure levels
Carcinogenicity: No direct evidence in humans, not classified by IARC
Mutagenicity: Negative in standard bacterial reverse-mutation (Ames) test; more studies ongoing
Reproductive Toxicity: Embryo-fetal toxicity reported in animal studies, contraindicated in pregnancy
Other Effects: Mild to moderate eye, skin, and respiratory irritation
Aquatic Toxicity: Data suggest harmful effects to aquatic organisms at high concentrations
Persistence and Degradability: Not known to degrade rapidly in the environment, may persist in soil or water
Bioaccumulative Potential: Limited data, log P indicates some potential for bioaccumulation
Mobility in Soil: Not highly mobile, binds to organic matter
Other Adverse Effects: No known ozone depletion potential, prudent use recommended to prevent environmental accumulation
Waste Treatment Methods: Dispose of in accordance with local, regional, and national regulations for hazardous waste
Disposal of Product: Incinerate in a facility equipped for pharmaceutical waste or send to authorized chemical disposal
Disposal of Contaminated Packaging: Triple rinse containers, then manage as hazardous waste per regulatory guidance
Precautions for Disposal: Never discharge into sewers, surface water, or soil systems
UN Number: Not assigned
UN Proper Shipping Name: Not regulated for ground, air, or sea transport
Transport Hazard Class: None for finished product
Packing Group: Not classified
Special Precautions: Protect from physical damage, moisture, and sunlight during shipment
Safety, Health and Environmental Regulations: Subject to pharmaceutical controls and prescription medicine regulations
Specific Legislation: Monitored under Drug Enforcement Administration for misuse, listed by FDA and EMA for safe production and use
Inventory Listings: Not registered in chemical inventory lists (TSCA, EINECS/ELINCS) as it is a pharmaceutical substance
Other Relevant Regulations: Environmental release restricted, reporting and monitoring required for workplace exposure and environmental disposal
