Trimetazidine: What is the competition-banned drug that Russian figure skater Kamila Valieva tested positive for?

A doping saga that has rumbled on since the 2022 Winter Olympic Games finally reached a conclusion on Monday.

Russian figure skater Kamila Valieva received a four-year ban from competition and saw her results since Christmas Day 2021 disqualified after Switzerland’s Court of Arbitration for Sport (CAS) said that the 17-year-old had been found guilty of an anti-doping violation after testing positive for the illegal drug trimetazidine in 2021.

The ban is backdated to December 25, 2021, which is when the sample was collected. Valieva was only 15 years old at the time.

The results of the test only came to light during the 2022 Winter Games in Beijing, where Valieva had helped lead the Russian Olympic Committee (ROC) – the neutral banner that Russian athletes were required to compete under after wider allegations of doping – to first place.

The ROC’s position has since been recalculated and ranked as third with the United States and Japan now being awarded the gold and silver medals.

But what exactly is the drug that triggered a high-profile doping scandal and eventually led to Valieva’s ban and disqualification?

According to the European Medicines Agency (EMA), trimetazidine “is a medicine used to prevent angina attacks, which are sudden pains to the chest, jaw and back brought on by physical effort, due to reduced blood flow to the heart.”

It has an effect on metabolism – where the body breaks down substances in order to convert them into energy. It increases the rate at which glucose is broken down, allowing it to be used to protect against myocardial ischaemia – reduced blood supply to the heart muscle – according to the EMA.

The EMA also states that it has been used to treat vertigo, tinnitus and reduced vision due to problems affecting the blood vessels.

It has been readily available in medicines in Europe since the 1970s and is marketed under the brand name Vastarel. Trimetazidine is not approved by the Food and Drug Administration for clinical use in the United States.

Trimetazidine is not well known as a doping drug in the US, but it is included on the World Anti-Doping Agency’s (WADA) 2024 list of prohibited substances and has been since the 2014 edition of the document.

It is listed as a “metabolic modulator” and its use by athletes is banned, both in and out of competition.

Though it would not increase heart rate, unlike other performance-enhancing drugs that are classed as stimulants, it is believed that trimetazidine can help with endurance in physical activity.

“What this drug does is actually make your heart work more efficiently,” Dr. Elizabeth Murray, pediatric emergency medicine physician at the University of Rochester Medical Center, told CNN’s Early Start program in 2022. “It doesn’t change your blood pressure very much or change your heart rate.

“An athlete wouldn’t get jittery or necessarily feel all that different, but they would theoretically be able to perform at a higher level for longer. It would increase their endurance, potentially.”

Previously, the best-known case involving the drug was when Chinese swimmer Sun Yang was handed a three-month suspension in 2014 after testing positive for trimetazidine.

Illegal metabolic modulators have been used by athletes in a variety of sports, including cycling, boxing and weightlifting and from dozens of countries including Russia, Poland, Colombia, Belgium and Germany. Former tennis world No. 1 Maria Sharapova was notably suspended in 2016 after testing positive for meldonium.

According to Murray, trimetazidine would not normally be given to children like Valieva “unless there’s a very good reason.”

The common side effects of trimetazidine, which can affect up to 1 in 10 people, are non-dangerous and include “gastrointestinal distress, tremors and weakness,” according to the National Capital Poison Center.

Serious side effects could include “Parkinsonian symptoms, involuntary muscle movements, and difficulty walking,” according to the poison center.

In 2012, the EMA completed a review into the safety and effectiveness of trimetazidine, after the French medicines regulatory agency reported that patients who had taken the drug experienced symptoms of Parkinson’s disease, such as tremor (shaking), muscle rigidity and walking disorders and restless legs syndrome.

“These symptoms were seen in some patients with no previous history of Parkinson syndrome, and in many cases their symptoms resolved when they stopped taking trimetazidine,” according to the the EMA Committee for Medicinal Products for Human Use.

The EMA’s Committee for Medicinal Products for Human Use eventually concluded that “benefits continue to outweigh the risks” in patients with issues relating to angina.

However, for use in treating tinnitus, vertigo and vision problems, “the benefits no longer outweigh the risks and the CHMP recommended that these uses should no longer be authorized.”