Folinic Acid, commonly known in pharmaceutical use as Calcium Folinate or Leucovorin Calcium, is a reduced folate derivative of folic acid. It is also known as 5-formyl-5,6,7,8-tetrahydrofolic acid and is used in pharmaceutical formulations as a folate rescue agent and in combination with certain anticancer therapies.
Calcium Folinate is the calcium salt of folinic acid. The USP monograph defines Leucovorin Calcium as containing NLT 95.0% and NMT 105.0% of leucovorin calcium, calculated on the anhydrous basis.
Folinic acid is a biologically active reduced folate and does not require the same reduction step as folic acid before participating in folate-dependent metabolic pathways. Pharmaceutical preparations of calcium folinate are used for methotrexate rescue, to reduce toxicity associated with folic-acid antagonists, and in combination with 5-fluorouracil (5-FU) in selected cancer treatment protocols.
| 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 | NMT 1.0% |
| Water Content | NMT 1.0% |