Levomefolic acid (

INN Inns are generally establishments or buildings where travelers can seek lodging, and usually, food and drink. Inns are typically located in the country or along a highway; before the advent of motorized transportation they also provided accommo ...

, also known as L-5-MTHF, L-methylfolate and L-5-methyltetrahydrofolate and (6''S'')-5-methyltetrahydrofolate, and (6''S'')-5-MTHF) is the primary biologically active form of

folate Folate, also known as vitamin B9 and folacin, is one of the B vitamins. Manufactured folic acid, which is converted into folate by the body, is used as a dietary supplement and in food fortification as it is more stable during processing an ...

used at the cellular level for DNA reproduction, the cysteine cycle and the regulation of

homocysteine Homocysteine is a non-proteinogenic α-amino acid. It is a homologue of the amino acid cysteine, differing by an additional methylene bridge (-CH2-). It is biosynthesized from methionine by the removal of its terminal Cε methyl group. In th ...

. It is also the form found in circulation and transported across membranes into tissues and across the blood–brain barrier. In the cell, L-methylfolate is used in the methylation of homocysteine to form methionine and

tetrahydrofolate Tetrahydrofolic acid (THFA), or tetrahydrofolate, is a folic acid derivative. Metabolism Human synthesis Tetrahydrofolic acid is produced from dihydrofolic acid by dihydrofolate reductase. This reaction is inhibited by methotrexate. It is co ...

(THF). THF is the immediate acceptor of one carbon unit for the synthesis of

thymidine Thymidine (symbol dT or dThd), also known as deoxythymidine, deoxyribosylthymine, or thymine deoxyriboside, is a pyrimidine deoxynucleoside. Deoxythymidine is the DNA nucleoside T, which pairs with deoxyadenosine (A) in double-stranded DNA. ...

-DNA, purines (RNA and DNA) and methionine. The un-methylated form, folic acid (vitamin B₉), is a synthetic form of folate, and must undergo enzymatic reduction by dihydrofolate reductase (DHFR) to become biologically active. It is synthesized in the absorptive cells of the small intestine from polyglutamylated dietary folate. It is a methylated derivative of tetrahydrofolate. Levomefolic acid is generated by methylenetetrahydrofolate reductase (MTHFR) from

5,10-methylenetetrahydrofolate 5,10-Methylenetetrahydrofolate (N5,N10-Methylenetetrahydrofolate; 5,10-CH2-THF) is cofactor in several biochemical reactions. It exists in nature as the diastereoisomer R5,10-methylene-THF. As an intermediate in one-carbon metabolism, 5,10-CH2 ...

(MTHF) and used to recycle homocysteine back to methionine by

methionine synthase Methionine synthase also known as MS, MeSe, MTR is responsible for the regeneration of methionine from homocysteine. In humans it is encoded by the ''MTR'' gene (5-methyltetrahydrofolate-homocysteine methyltransferase). Methionine synthase forms ...

(MS). L-Methylfolate is water-soluble and primarily excreted via the kidneys. In a study of 21 subjects with coronary artery disease, peak plasma levels were reached in one to three hours following oral or parenteral administration. Peak concentrations were found to be more than seven times higher than folic acid (129 ng/ml vs. 14.1 ng/ml).

Metabolism

Medical uses

Major depressive disorder

Research suggests that levomefolic acid (L-methylfolate) taken with a first-line antidepressant provides a modest adjunctive antidepressant effect for individuals who do not respond or have only a partial therapeutic response to

SSRI Selective serotonin reuptake inhibitors (SSRIs) are a class of drugs that are typically used as antidepressants in the treatment of major depressive disorder, anxiety disorders, and other psychological conditions. SSRIs increase the extracellul ...

or SNRI medication, and might be a more cost-effective adjunctive agent than second-generation antipsychotics.

Cardiovascular disease and cancer

Levomefolic acid (and folic acid in turn) has been proposed for treatment of cardiovascular disease and advanced cancers such as breast and colorectal cancers. It bypasses several metabolic steps in the body and better binds thymidylate synthase with FdUMP, a metabolite of the drug fluorouracil.

Patent issues

In March 2012, Merck & Cie of Switzerland, Pamlab LLC (maker of Metanx and Cerefolin, Neevo DHA, and Deplin), and South Alabama Medical Science Foundation (SAMSF) (the plaintiffs) filed a complaint in the

United States District Court for the Eastern District of Texas The United States District Court for the Eastern District of Texas (in case citations, E.D. Tex.) is a federal court in the Fifth Circuit (except for patent claims and claims against the U.S. government under the Tucker Act, which are appealed to ...

against four defendants: Macoven Pharmaceuticals (owned by Pernix Therapeutics), Gnosis SpA of Italy, Gnosis U.S.A and Gnosis Bioresearch Switzerland. The plaintiffs alleged that the defendants infringed on several of the plaintiffs' patents.The six patents named were , , , , and . The Macoven products named in the suit are: "Vitaciric-B", "ALZ-NAC", "PNV DHA", and l-methylfolate calcium (levomefolate calcium). In September 2012, the same three plaintiffs filed a complaint requesting that the International Trade Commission begin an investigation of the same four defendants. The complaint states that Gnosis' "Extrafolic-S" and products which are made from it, infringe upon three of their patents: , , and .

Formulations

Levomefolate calcium, a calcium

salt Salt is a mineral composed primarily of sodium chloride (NaCl), a chemical compound belonging to the larger class of salts; salt in the form of a natural crystalline mineral is known as rock salt or halite. Salt is present in vast quant ...

of levomefolic acid is sold under the brand name Metafolin and incorporated in Deplin. Levomefolate magnesium is a magnesium salt of levomefolic acid, manufactured as DeltaFolate, a primary ingredient in EnLyte.

References

External links

CALCIUM L-5-METHYLTETRAHYDROFOLATE (L-5-MTHF-Ca)
* * {{Vitamin Folates Coenzymes Medical food Patent case law