Inventor of drug in Sharapova case says it's 'not doping'

RIGA, Latvia - Meldonium doesn't enhance the performance of athletes, the Latvian scientist who invented the drug at the center of Maria Sharapova's doping case told The Associated Press.

Ivars Kalvins said that the drug ''is not doping,'' but added it does protect athletes against heart damage during extreme physical exercise.

If the heart is working very hard, the drug ''protects the heart cells ... against ischemia,'' a blood circulation condition, Kalvins said. ''This is not the same as increase of performance.''

Meldonium, a heart medicine that improves blood flow, was banned by the World Anti-Doping Agency on Jan. 1. WADA says it was prohibited ''because of evidence of its use by athletes with the intention of enhancing performance.''

Sharapova, a five-time Grand Slam champion, admitted she failed a doping test at the Australian Open in January for meldonium, which she said she had been using for 10 years for various medical issues.

The drug, which is not approved by the U.S. Food and Drug Administration, was once common in the Soviet military, Kalvins said.

He said he believes many militaries around the world are still giving the drug to soldiers ''because if the ischemia is caused by, let's say, the lack of oxygen in the air in mountains or whatever, in planes or in submarines, etc., it will protect the soldiers against damages.''

Also known as mildronate, the drug was banned because it aids oxygen uptake and endurance, and several athletes in various international sports have already been caught using it since it was prohibited.

It is normally prescribed for four to six weeks.

Grindeks, the Latvian company that manufactures mildronate, says it was one of the most important drug research centers in in the Soviet Union during the Cold War. It changed its name to Grindeks when Latvia regained independence in 1991. The company was privatized in 1997 and listed on the Latvian stock exchange a year later.

Mildronate is Grindeks' top-selling drug and a promotional video on the company website calls it a ''great pride for Grindeks and Latvia as a whole.''

The company doesn't disclose sales figures for individual drugs but its total sales of drugs and pharmaceutical ingredients in 2015 exceeded 82 million euros ($90 million).