Ligandrol (VK5211, LGD-4033)is a novel nonsteroidal oral selective androgen receptor modulator (SARM) for treatment of conditions such as muscle wasting and osteoporosis,discovered by Ligand Pharmaceuticals and currently under development by Viking Therapeutics.

LGD-4033 has been found in World Anti-Doping Agency (WADA) samples and in racehorses too. Like anabolic steroids, it can stimulate muscle growth. "SARMs have shown superior side effect profiles compared with anabolic steroids, which arguably makes them attractive for use by individuals seeking an unfair advantage over their competitors".

Misbranded as dietary supplement

On 23 October 2017, a nutritional supplement company in Missouri called Infantry Labs was warned by the FDA that the distribution of two of its products violated the Federal Food, Drug, and Cosmetic Act. One of the substances was LGD-4033. The company advertised as benefits of the ligandrol: "increases in lean body mass and decrease in body fat" and "increases in strength, well being, as well as healing possibilities". The company mislabeled as "dietary supplements" what should have been "new drugs" or "prescription drugs" and were instructed to document the steps they would take in order to cease the violation.

Also on 23 October 2017, the FDA sent a warning letter to a New Jersey company called Panther Sports Nutrition. The behaviour of the company was similar to the Infantry Labs case. The product was advertised as a "mass builder" and "physique enhancing agent".

Clinical Research

According to a clinical trial conducted at the Boston Medical Center's Section of Endocrinology, Ligandrol can help improve lean body mass and muscle strength.

Another study conducted in January 2013 found that LGD-4033 can help increase lean muscle mass, and was generally well tolerated by test subjects.

Side effects

The FDA claims that "liver toxicity, adverse effects on blood lipid levels, and a potential to increase the risk of heart attack and stroke" are among the adverse health effects of SARMs.