Pibrentasvir is a modern direct-acting antiviral pharmaceutical active ingredient developed for the treatment of chronic hepatitis C virus (HCV) infection. Pibrentasvir CAS Number 1353900-92-1 is the primary chemical identifier for this API, which is also known by the development code ABT-530. It belongs to the NS5A inhibitor class of HCV antivirals and is used in combination with glecaprevir, an HCV NS3/4A protease inhibitor, to provide a multi-target approach to suppressing viral replication. Pibrentasvir is therefore an important API for pharmaceutical development and manufacturing programs focused on modern HCV treatment. FDA identifies pibrentasvir as a white to off-white to light-yellow crystalline powder with a molecular formula of C57H65F5N10O8 and a molecular weight of 1113.18 g/mol.
The molecular structure of pibrentasvir is considerably more complex than that of many conventional small-molecule APIs. It contains fluorine atoms, multiple nitrogen and oxygen functionalities, and several defined stereocenters. These structural characteristics contribute to its pharmacological activity as well as its physicochemical behavior. Pibrentasvir has eight defined stereocenters, making control of chemical identity and stereochemical integrity important aspects of pharmaceutical API quality. The compound also has high lipophilicity and a relatively high molecular weight, which are relevant when considering analytical characterization, formulation development, and material handling.
Pibrentasvir acts directly against HCV by targeting the viral NS5A protein, an essential component of the hepatitis C replication process. NS5A participates in multiple stages of the viral life cycle, and inhibition of this protein contributes to suppression of viral replication. Pibrentasvir is particularly valuable because of its broad genotype coverage when used in the approved glecaprevir/pibrentasvir combination.
The combination of glecaprevir and pibrentasvir is marketed as Mavyret in the United States and Maviret in several other markets. FDA-approved labeling describes the combination as a direct-acting antiviral regimen for chronic HCV infection caused by genotypes 1 through 6 in appropriate patient populations. This makes pibrentasvir an important component of contemporary HCV pharmaceutical therapy.
From an API perspective, pibrentasvir is relevant to manufacturers developing or supplying active pharmaceutical ingredients for antiviral drug products. Its complex structure requires appropriate process development, impurity control, analytical method validation, and batch-to-batch consistency.
Pibrentasvir has the molecular formula C57H65F5N10O8 and molecular weight 1113.18 g/mol. Its high molecular weight and complex molecular architecture distinguish it from simpler antiviral APIs. The compound is described as a crystalline powder and has very limited aqueous solubility.
FDA data report that pibrentasvir has solubility of less than 0.1 mg/mL across pH 1–7 at 37°C. It is therefore considered a low-solubility drug substance. This property is important during pharmaceutical formulation because conventional aqueous systems may not provide adequate solubilization. Appropriate formulation strategies and controlled material characteristics are consequently important for achieving consistent pharmaceutical performance.
The API is also reported to be freely soluble in ethanol. Its physicochemical characteristics should be evaluated using validated analytical procedures appropriate for the drug substance rather than relying on generic small-molecule API assumptions.
High-quality pibrentasvir API requires comprehensive analytical characterization. Identification testing establishes the chemical identity of the active ingredient, while chromatographic procedures can be used to evaluate assay and related substances. Because of the complexity of the molecule, impurity profiling is an important part of the quality-control strategy.
Potential quality attributes may include process-related impurities, degradation products, residual solvents, elemental impurities, water content, solid-state characteristics, and stereochemical integrity. The precise numerical limits should be taken from the applicable approved API specification or regulatory dossier. A universal commercial specification should not be assumed where an authoritative public numerical value is unavailable.
The crystalline nature of pibrentasvir also makes appropriate solid-state characterization relevant. Techniques such as XRPD, DSC, or other validated methods may be incorporated into a pharmaceutical development and quality-control program when required by the applicable specification.
Pibrentasvir manufacturing involves a complex chemical synthesis and requires careful control of reaction conditions, starting materials, intermediates, purification steps, and final isolation. Because the molecule contains multiple functional groups and stereochemical elements, manufacturing controls must be designed to maintain the required structural and stereochemical profile throughout the process.
Purification is particularly important for controlling closely related substances and process impurities. Final API testing should confirm identity, assay, purity, residual solvents, elemental impurities, and other critical quality attributes established for the intended pharmaceutical application.
A pharmaceutical-grade pibrentasvir API manufacturing program should also maintain appropriate batch documentation and traceability. Depending on the intended market and customer requirements, documentation may include a Certificate of Analysis, analytical methods, specification sheets, stability information, and regulatory-quality documentation.
Pibrentasvir should be stored and handled according to the manufacturer's validated stability data and approved API specification. Appropriate packaging should protect the material from environmental conditions that could affect its quality. Temperature, moisture exposure, packaging integrity, and storage duration should be controlled according to established stability requirements.
Because pibrentasvir is a complex crystalline API with very low aqueous solubility, maintaining consistent physical characteristics can be important during storage and subsequent pharmaceutical processing. Any special handling requirements should be established through stability studies and the applicable quality system.
Pibrentasvir CAS Number 1353900-92-1 is a significant pharmaceutical API for HCV antiviral development. Its combination of potent NS5A activity, broad HCV genotype application in combination therapy, complex molecular structure, and low aqueous solubility makes it an API requiring sophisticated pharmaceutical development and analytical control.
For pharmaceutical manufacturers, consistent API quality depends on control of chemical identity, purity, stereochemistry, solid-state characteristics, residual solvents, elemental impurities, and other critical quality attributes. Using validated analytical methods and documented manufacturing controls helps support reproducible API quality and suitability for further pharmaceutical processing.
| Parameter | Information |
|---|---|
| Product Name | Pibrentasvir |
| CAS Number | 1353900-92-1 |
| Development Code | ABT-530 |
| Molecular Formula | C57H65F5N10O8 |
| Molecular Weight | 1113.18 g/mol |
| Exact Mass | 1112.4907 Da |
| API Class | Direct-Acting Antiviral |
| Target | HCV NS5A |
| Appearance | White to off-white to light-yellow crystalline powder |
| Water Solubility | <0.1 mg/mL at pH 1–7, 37°C |
| Ethanol Solubility | Freely soluble |
| Stereocenters | 8 defined stereocenters |
| Pharmacological Application | Chronic hepatitis C |
| Combination API | Glecaprevir |
Pharmaceutical-grade pibrentasvir requires more than a high assay result. Reliable API quality involves consistent chemical identity, controlled impurities, appropriate stereochemical integrity, reproducible physical characteristics, and compliance with applicable pharmaceutical quality requirements. Analytical testing should be performed using validated methods suitable for this complex antiviral molecule.
For pharmaceutical development and commercial manufacturing, pibrentasvir should be evaluated against the customer's approved specification and applicable regulatory requirements. This approach ensures that quality attributes are appropriately defined without incorrectly applying generic specifications that may not be suitable for this particular API.
Pibrentasvir CAS Number 1353900-92-1 therefore represents a specialized antiviral API with important applications in modern HCV therapy and pharmaceutical development. Its established NS5A mechanism, complex chemical structure, broad clinical relevance in combination therapy, and distinctive physicochemical properties make accurate characterization and controlled manufacturing essential for pharmaceutical-grade material.
| Parameter | Specification |
|---|---|
| Appearance | white to off-white crystalline powder |
| Identification | IR & HPLC compliant |
| Assay (HPLC) | 98.0% – 102.0% |
| Loss on Drying | NMT 1.0% |
| Residue on Ignition | NMT 0.1% |
| Individual Impurity | NMT 0.5% |
| Water Content | NMT 1.0% |
| Solubility | <0.1 mg/mL across pH 1–7 at 37°C |