Pemetrexed Disodium API is a synthetic antifolate pharmaceutical substance used in oncology drug development and manufacturing. It belongs to the class of folate analogue metabolic inhibitors and interferes with multiple folate-dependent enzymes required for the synthesis of DNA and RNA.
Pemetrexed is supplied as a disodium salt and can exist in different hydrate forms. This makes accurate identification of the salt and hydration state particularly important for API procurement, analytical testing, formulation development and regulatory documentation.
The commonly referenced CAS number for pemetrexed disodium is 150399-23-8. The molecular weight depends on the specific solid form: the anhydrous disodium salt is approximately 471.40 g/mol, the hemipentahydrate is approximately 516.41 g/mol, and the heptahydrate is approximately 597.49 g/mol.
Pemetrexed is an established oncology drug substance used in pharmaceutical formulations for specific types of cancer. It is associated particularly with the treatment of malignant pleural mesothelioma and selected forms of non-small-cell lung cancer (NSCLC).
Pemetrexed inhibits several enzymes involved in folate metabolism and nucleotide biosynthesis. Its principal biochemical targets include:
Through inhibition of these enzymes, pemetrexed reduces the availability of nucleotide precursors required for DNA and RNA synthesis, thereby interfering with cancer-cell proliferation.
A professional Pemetrexed Disodium API manufacturer in India should maintain stringent controls over chemical purity, assay, related substances, residual solvents, elemental impurities and solid-state characteristics.
Because pemetrexed disodium can be supplied in different hydrate forms, the manufacturer's specification should clearly identify the intended form. Water content and molecular weight should correspond to the declared hydrate state.
For pharmaceutical buyers, a reliable supplier should provide appropriate batch-specific documentation, including a Certificate of Analysis, specification sheet and relevant analytical information.
Pemetrexed disodium is a synthetic pharmaceutical substance manufactured through controlled chemical synthesis followed by purification and isolation of the required salt/solid form.
Manufacturing controls typically focus on:
The final API should be characterized using validated analytical procedures suitable for the actual pemetrexed disodium form being manufactured.
Molecular Formula: C20H19N5Na2O6
Molecular Weight: 471.40 g/mol
This represents the anhydrous disodium salt and should not be confused with the hydrated API forms.
Molecular Formula: C20H19N5Na2O6·2.5H2O
Molecular Weight: 516.41 g/mol
The hemipentahydrate contains 2.5 molecules of water per pemetrexed disodium molecule.
Molecular Formula: C20H19N5Na2O6·7H2O
Molecular Weight: 597.49 g/mol
The heptahydrate contains seven molecules of water per pemetrexed disodium molecule.
For an API product page, the hydrate form should always match the actual material supplied.
Quality control is an important part of Pemetrexed Disodium API manufacturing. Appropriate testing can include chromatographic identification, assay, related substances, residual solvents, water determination and elemental impurity assessment.
Because the API may exist as a defined hydrate, water content is a critical form-related characteristic. A water specification should therefore be established according to the actual hydrate form and validated manufacturing process rather than using an arbitrary generic value.
Analytical testing for pemetrexed disodium should use validated procedures capable of distinguishing the active substance from process-related and degradation-related impurities.
HPLC is commonly suitable for assay and related-substance analysis. Additional analytical techniques may be used for identity and solid-state characterization.
For hydrate-specific products, techniques such as Karl Fischer water determination, thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), XRPD and other solid-state techniques may be useful for confirming hydration and physical form.
This is particularly important because the molecular weight and theoretical water content differ between the anhydrous, hemipentahydrate and heptahydrate forms.
Pemetrexed is soluble in water, and an experimental solubility value of approximately 89.4 g/L has been reported in PubChem.
For a commercial API specification, however, the value should not automatically be treated as an official universal saturation-solubility specification. Solubility can depend on temperature, pH, ionic conditions and the specific solid form.
Solubility: Soluble in water; reported experimental solubility approximately 89.4 g/L.
Storage conditions for the API should follow the supplier's validated stability data and approved product specification. The material should be protected from inappropriate environmental exposure and stored in a properly closed container under controlled conditions.
For a pharmaceutical API website, it is preferable to state:
Storage: Store in a well-closed container under recommended controlled storage conditions according to the manufacturer's validated stability specification.
Avoid assigning an arbitrary temperature range unless it is supported by the actual API manufacturer's stability data.
Pemetrexed disodium should be packaged using suitable pharmaceutical-grade packaging that protects the material from moisture, contamination and environmental exposure.
Typical pharmaceutical API documentation may specify:
Actual packaging configuration should correspond to the manufacturer's validated packaging system.
When selecting a Pemetrexed Disodium API supplier, pharmaceutical manufacturers should evaluate product quality, consistency, documentation and regulatory support.
Important supplier evaluation criteria include:
The supplier should clearly identify whether the material is anhydrous pemetrexed disodium, hemipentahydrate or heptahydrate.
Each batch should meet the applicable approved specification for assay, impurities and physical characteristics.
A batch-specific Certificate of Analysis should provide the relevant test results and specification limits.
Where applicable, pharmaceutical buyers may request regulatory and quality documentation supporting the intended use of the API.
The supplier should have appropriate stability data supporting the recommended storage and retest conditions.
Pemetrexed disodium offers several characteristics important to pharmaceutical manufacturers:
For pharmaceutical manufacturing, the identity and quality of pemetrexed disodium must be established using validated analytical methods. The API should meet the applicable specification for its declared form and intended pharmaceutical application.
Particular attention should be paid to hydrate state, water content and molecular weight, because these parameters are directly related to the composition of the solid substance.
A professional API supplier should maintain appropriate controls throughout synthesis, purification, drying and packaging to ensure consistent product quality.
Pemetrexed disodium API is the disodium salt of pemetrexed, a synthetic antifolate used as an active pharmaceutical ingredient in oncology formulations.
The commonly referenced CAS number is 150399-23-8.
It depends on the solid form:
Pemetrexed is used in oncology for specific indications involving malignant pleural mesothelioma and non-small-cell lung cancer.
Yes. Pemetrexed is reported to be soluble in water. An experimental solubility of approximately 89.4 g/L has been reported.
The hydrate form changes the molecular weight and water content of the API. Therefore, the exact hydrate state should be specified on the API specification and Certificate of Analysis.
No. Pemetrexed disodium is a synthetic small-molecule pharmaceutical API, unlike PEGylated proteins such as peginterferon or pegfilgrastim.
Pemetrexed belongs to the antineoplastic/antimetabolite class and is specifically classified as a folate analogue metabolic inhibitor.
| 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 0.5% |
| Heavy Metals | NMT 10 ppm |
| pH (1% Solution) | 2.0 – 4.0 |
| Individual Impurity | NMT 0.5% |
| Total Impurities | ≤ 1.5% |