Ombitasvir is a direct-acting antiviral pharmaceutical compound developed as an inhibitor of the hepatitis C virus (HCV) NS5A protein. It is also known by the development code ABT-267 and is identified by CAS Number 1258226-87-7. Ombitasvir has the molecular formula C50H67N7O8 and an anhydrous molecular weight of approximately 894.11 g/mol. Regulatory documentation describes the drug substance as a hydrate, with the molecular formula C50H67N7O8·4.5H2O and molecular weight 975.20 g/mol for the hydrate form.
Ombitasvir belongs to the class of HCV NS5A inhibitors. NS5A is an essential HCV protein involved in viral replication, making it an important target for direct-acting antiviral research and pharmaceutical development. EMA documentation describes ombitasvir as one of the active substances in the former Viekirax combination, together with paritaprevir and ritonavir.
Ombitasvir is a structurally complex, stereochemically defined small molecule containing multiple amide and carbamate functionalities. The compound has six chiral centres, and regulatory assessment documentation states that its structure was confirmed using techniques including mass spectrometry, infrared spectroscopy, proton and carbon-13 NMR, X-ray crystallography, UV analysis and solid-form characterization.
The anhydrous compound has a molecular weight of 894.11 g/mol, while the pharmaceutical drug substance described by EMA is a 4.5-hydrate, giving a molecular weight of 975.20 g/mol. This distinction is particularly important when preparing API documentation, certificates of analysis, specifications, purchasing documentation and regulatory records.
Ombitasvir is a non-structural protein 5A (NS5A) inhibitor. NS5A is an essential protein required for HCV replication. By inhibiting NS5A, ombitasvir interferes with processes necessary for viral replication and propagation. EMA documentation identifies ombitasvir as the NS5A component of the ombitasvir/paritaprevir/ritonavir combination.
Research sources report very high in-vitro potency, with EC50 values in the picomolar range against several HCV genotypes. MedChemExpress reports EC50 values of 0.82–19.3 pM for HCV genotypes 1–5 and 366 pM for genotype 6a. These values describe antiviral research activity and should not be confused with an API quality specification.
Ombitasvir is primarily associated with antiviral pharmaceutical development and HCV treatment combinations. Historically, it was used as part of fixed-dose or combination antiviral regimens. EMA documentation identifies Viekirax as a combination containing 12.5 mg ombitasvir, 75 mg paritaprevir and 50 mg ritonavir per tablet.
The compound has therefore been relevant to:
Ombitasvir API should be clearly differentiated from combination drug products containing ombitasvir. The API page concerns the active substance itself rather than the finished tablet formulation.
Quality evaluation of Ombitasvir can involve a combination of chromatographic, spectroscopic and physicochemical techniques. HPLC is commonly used to evaluate purity and related substances, while LC-MS, MS, NMR and IR can support identity confirmation.
Commercial analytical references report high-purity Ombitasvir material. MedChemExpress lists batches with reported purity values around 98% and above, including a displayed batch assay/purity of 99.98%. Selleck reports a batch purity of 99.77%. These are supplier-specific batch results rather than universal pharmacopoeial API limits.
For a commercial API specification, parameters such as assay, related substances, residual solvents, water content, residue on ignition, elemental impurities and stereochemical purity should be controlled according to the applicable validated specification and regulatory requirements.
Regulatory information describes Ombitasvir drug substance as a white to light yellow to light pink powder and reports that it is practically insoluble in aqueous buffers but soluble in ethanol. The EMA assessment also reports a pKa of approximately 2.5 and a high distribution coefficient under the stated test conditions.
Research-grade product information also describes Ombitasvir as a solid ranging from white to light yellow in appearance. Storage recommendations for research material commonly include −20°C for long-term powder storage, although actual commercial API storage conditions should always follow the validated manufacturer's stability data and approved packaging/storage instructions.
Ombitasvir Bulk API documentation should specify the exact material form, particularly whether the material is being represented on an anhydrous basis or as the hydrate drug substance. The distinction between 894.11 g/mol anhydrous Ombitasvir and 975.20 g/mol Ombitasvir 4.5-hydrate is important for technical documentation and quantitative calculations.
For pharmaceutical procurement, technical teams should review the applicable certificate of analysis, analytical method, impurity profile, residual-solvent profile, water/hydrate status and stability information before approving an API batch.
The principal CAS Number for Ombitasvir is 1258226-87-7. FDA's Global Substance Registration System identifies Ombitasvir with this CAS number and UNII 2302768XJ8.
A separate hydrate form is identified in the FDA/NCATS substance database as Ombitasvir Heminonahydrate, CAS 1456607-70-7. This is relevant when the material documentation specifically identifies the hydrate form.
Ombitasvir API is a specialized antiviral pharmaceutical ingredient requiring stringent control of identity, stereochemistry, purity, related substances and solid-state characteristics. An API manufacturer in India working with Ombitasvir should maintain appropriate analytical controls and documentation for pharmaceutical development and quality evaluation.
For an Ombitasvir API Manufacturer India product page, the most important searchable identifiers include Ombitasvir API, Ombitasvir API Manufacturer, Ombitasvir API Manufacturer India, Ombitasvir Pharmaceutical API, Ombitasvir Bulk API, Ombitasvir CAS Number, ABT-267 API and CAS 1258226-87-7.
| Parameter | Specification |
|---|---|
| Appearance | white to off-white crystalline powder |
| Identification | IR & HPLC compliant |
| Assay (HPLC) | 98.0% – 102.0% |
| Loss on Drying | NMT 0.5% |
| Residue on Ignition | NMT 0.20% |
| Individual Impurity | NMT 0.20% |
| Total Impurities | NMT 0.50% |