Posaconazole is a synthetic, broad-spectrum triazole antifungal active pharmaceutical ingredient used for the prevention and treatment of serious invasive fungal infections. It is identified by CAS No. 171228-49-2, molecular formula C₃₇H₄₂F₂N₈O₄, and molecular weight 700.78 g/mol. FDA identifies Posaconazole as the drug substance used in oral suspension, delayed-release tablets and intravenous formulations.
Posaconazole belongs to the triazole class of antifungal agents and acts by inhibiting fungal sterol biosynthesis, particularly the enzyme involved in conversion of lanosterol to ergosterol. It has activity against a broad range of pathogenic fungi, including Aspergillus and Candida species.
Posaconazole is a highly lipophilic, stereochemically defined small molecule. FDA documentation gives the molecular formula C₃₇H₄₂F₂N₈O₄ and molecular weight 700.8 g/mol.
Commercial analytical specifications from TCI identify Posaconazole as a solid with minimum 98.0 area% HPLC purity, melting point 167.0–171.0°C, and specific rotation −24.0 to −28.0° (c=1, CHCl₃).
| Parameter | Details |
|---|---|
| Product Name | Posaconazole |
| API Form | Posaconazole |
| CAS Number | 171228-49-2 |
| Molecular Formula | C₃₇H₄₂F₂N₈O₄ |
| Molecular Weight | 700.78 g/mol |
| Molecular Type | Small-Molecule API |
| Therapeutic Class | Triazole Antifungal |
| Physical State | Solid |
| Appearance | White to light-yellow powder to crystal |
| Melting Point | 167.0–171.0°C |
| Specific Rotation | −24.0 to −28.0° (c=1, CHCl₃) |
| Water | NMT 1.0% — commercial analytical specification |
| Storage | Frozen / below 0°C for TCI analytical material |
TCI reports the above physical specifications, while Sigma's analytical standard specifies water ≤1.0% and specific rotation −27.5 ± 2.5°.
Posaconazole is used for the prophylaxis of invasive Aspergillus and Candida infections in high-risk immunocompromised patients. Current U.S. labeling includes use in patients with hematologic malignancies with prolonged neutropenia and hematopoietic stem-cell transplant recipients with graft-versus-host disease.
Posaconazole is available in several pharmaceutical dosage forms, including delayed-release tablets, oral suspension/powder for delayed-release oral suspension and intravenous formulations. FDA documentation confirms that the same Posaconazole drug substance is used across different formulations.
Posaconazole API can be characterized using:
FDA's CMC documentation confirms that Posaconazole drug-substance specifications are used to assure identity, strength, quality and purity.
Published analytical studies also demonstrate validated HPLC methods for Posaconazole bulk drug substance and investigation of degradation products by LC-MS techniques.
Posaconazole API requires controlled synthesis, purification, stereochemical control and analytical characterization. Manufacturing controls can include assay, related substances, water, residual solvents, crystalline form and optical rotation.
The appropriate release specification should be based on the manufacturer's validated pharmaceutical specification and applicable pharmacopoeial/regulatory requirements.
Posaconazole should be protected from excessive heat, moisture and unsuitable environmental conditions.
For TCI analytical Posaconazole, the stated storage condition is frozen, below 0°C, and the material is identified as heat-sensitive.
The storage condition for a commercial pharmaceutical API should ultimately follow its validated stability data and approved specification rather than automatically copying a research-standard storage condition.
Typical documentation may include:
| Parameter | Specification |
|---|---|
| Identification | IR & HPLC compliant |
| Assay (HPLC) | NLT 98.0% |
| Loss on Drying | NMT 0.5% |
| Residue on Ignition | NMT 0.10% |
| Individual Impurity | NMT 0.10% |
| Total Impurities | NMT 0.50% |
| Water Content | NMT 1.0% |
| Specific Rotation | −24.0 to −28.0° (c=1, CHCl₃) |
| Melting Point | 167.0–171.0°C |