Meldonium

# Overview
Meldonium (also known as Mildronate, THP, MET-88, Mildronats or Quaterine) is a clinically used anti-ischemic drug that is currently manufactured and marketed by Grindeks, a pharmaceutical company based in Latvia.  It is used in Lithuania and the Russian Federation, but is not approved by the Food and Drug Administration for use in the United States.

# Medical use
Meldonium is clinically used to treat angina and myocardial infarction. The first clinical trial testing the efficacy of using a combination of meldonium and lisinopril, an angiotensin-converting enzyme inhibitor, to treat chronic heart failure was reported in 2005. The report demonstrated that the combined treatment of meldonium and lisinopril may improve the quality of life, exercise capacity and mechanisms of peripheral circulation of patients with chronic heart failure. A later report in 2008 further demonstrated the efficacy of combined meldonium-lisinopril treatment by showing improved carotid baroreceptor reflex in patients with chronic heart failure. In February 2010, the clinical trial testing the efficacy and safety of meldonium treatment in combination with standard exercise tolerance therapy on angina patients was successfully completed. The studies revealed that meldonium treatment significantly improves the exercise tolerance of stable angina patients. A phase II clinical trial on the efficacy and safety of meldonium for acute ischemic stroke was completed in August 2013 and the studies showed that meldonium is as effective and safe as cinepazide injection.
Besides clinical trials, a number of scientific research projects have also been conducted to improve the efficacy of meldonium and its applicability to other diseases. For example, a report published by Vilskersts et al. suggested that the effect of mildronate treatment may be enhanced with co-treatment of other compounds such as orotic acid.
Using animal models, the applications of meldonium, sometimes in tandem with other drugs such as metformin, have shown beneficial effects on neurological disorder and diabetes.
Meldonium may also be beneficial for the treatment of seizures and alcohol intoxication.
Recent reports also suggest that meldonium may improve the ability of learning and memory, as the drug changes the expression of hippocampal proteins related to synaptic plasticity using rat model.
Meldonium was reported to elevate the concentrations of -butyrobetaine hydroxylase in testes tissues; in addition, long term (90 days) administration of meldonium was reported to improve sexual performance, sperm motility and concentration of testosterone in boars, although further studies are needed to confirm the potential of using meldonium as a sperm motility and sperm quality-enhancing agent.
To date, meldonium is one of Latvia's most exported products, and can be readily obtained in countries including Russia, Ukraine, Moldova, Belarus, Azerbaijan and Armenia.

# Mechanism of action
The chemical name of meldonium is 3-(2,2,2-trimethylhydraziniumyl)propionate, a structural analogue of -butyrobetaine, with a NH group replacing the CH2 at the C-4 position of -butyrobetaine. -Butyrobetaine is a precursor in the biosynthesis of carnitine.
The mechanism of action of meldonium is to act as a fatty acid oxidation inhibitor, presumably by inhibiting enzymes in the carnitine biosynthesis pathway such as -butyrobetaine hydroxylase. -Butyrobetaine hydroxylase is an enzyme that belongs to the 2-oxoglutarate (2OG) oxygenase superfamily and catalyses the formation of L-carnitine from -butyrobetaine. X-ray crystallographic and in vitro biochemical studies suggest meldonium binds to the substrate pocket of -butyrobetaine hydroxylase and acts as a competitive substrate/inhibitor to form malonic acid semialdehyde, dimethylamine, formaldehyde, 3-amino-4-(methyamino)butanoic acid and (1-methylimidazolidin-4-yl)acetic acid, likely via a Steven's type rearrangement mechanism. Mildronate is a potent -butyrobetaine hydroxylase inhibitor, with a half maximal inhibitory concentration (IC50) value of 62 M. Meldonium is an example of a non-peptidyl substrate mimic inhibitor for human 2OG oxygenase.
Meldonium has also been shown by NMR to bind to carnitine acetyltransferase. Carnitine acetyltransferase belongs to a family of ubiquitous enzymes that play pivotal roles in cellular energy metabolism. Meldonium therefore may act as a regulator of energy metabolism. Meldonium is a relatively weak inhibitor to carnitine acetyltransferase (when compared to -butyrobetaine hydroxylase), with an inhibition constant (KI) of 1.6 mM.

# Forms
- 250 mg capsules N60
- 500 mg capsules N60
- Injection 10% 5 ml N10