Fortetropin® Supplementation Prevented a Rise in Myostatin During a Period of Muscle Disuse

MYOS CORP, a research-based, advanced nutrition company, announced the completion of a randomized, double blind, placebo-controlled human clinical trial conducted at McMaster University, Canada, that examined the impact of Fortetropin® on young men during periods of muscle disuse. The trial showed that Fortetropin supplementation prevented a rise in myostatin during a period of muscle disuse. Myostatin is a protein that arrests the growth and development of new muscle tissue. This finding is a significant addition to MYOS CORP’s robust portfolio of clinical research proving the muscle health efficacy of Fortetropin.

“The impact of Fortetropin® on serum myostatin concentrations in human subjects that participated in this clinical trial is intriguing,” stated Stuart Phillips, Ph.D., Professor of Kinesiology and Canada Research Chair, the Principal Investigator of this human clinical trial. “Fortetropin has now shown efficacy in reducing Myostatin in 3 clinical studies. Very few nutritional supplements have been studied as rigorously as Fortetropin® has been studied in human and preclinical studies. A safe, product that can prevent increases in serum myostatin has exciting potential, particularly in aging person’s rehab and recovery from injury.”

In order to assess the impact of Fortetropin on muscle disuse atrophy on human subjects, a model known as the unilateral leg immobilization model was utilized, which involved each subject wearing a knee brace for two weeks in order to simulate acute muscle inactivity. Subjects were required to consume their assigned supplement (Fortetropin® or macronutrient-matched placebo) for two weeks prior to the activity restriction phase of the study and continued to consume their assigned supplement for an additional two weeks during the recovery phase of the study.

One of the remarkable findings from this study was that while the subjects supplemented with the placebo did experience a statistically significant increase in plasma concentrations of myostatin during activity restriction, the subjects supplemented with Fortetropin® did not show any statistically significant changes in plasma myostatin concentrations.

“The results of this study are very exciting for MYOS CORP, and for the larger sports nutrition and age management fields,” said Joseph Mannello, MYOS CORP CEO. “Since the myostatin gene was discovered in 1997, many pharmaceutical companies have been actively engaged in developing myostatin inhibitors. Unfortunately, myostatin inhibitors sometimes fall into the wrong hands and are abused. These drugs can have very harmful side effects and should never be used without supervision from a physician. Fortetropin is a safe, natural product that is derived from fertilized, chicken egg yolk. It has tremendous potential to help humans stay active and healthy at every stage of life.”

The results observed in this human clinical trial with respect to myostatin mirror results that were published in 2020 by veterinary researchers at Kansas State University College of Veterinary Medicine. In this earlier study, 100 dogs were forced to undergo an 8-week period of activity restriction while recovering from a common veterinary surgical procedure known as tibial plateau leveling osteotomy (TPLO) which is performed to repair tears of the canine cruciate ligament (CCL). 50 dogs were supplemented with Fortetropin and 50 dogs were supplemented with a macronutrient matched placebo. Dogs that were supplemented with a macronutrient matched placebo experienced an average increase in myostatin concentration of ~10% after eight weeks had elapsed following surgery, while no statistically significant changes had been observed in dogs that were supplemented with Fortetropin®.

Research published in 2021 by researchers at the University of California, Berkeley revealed that older men and women (60-75 years old) that were supplemented with Fortetropin® experienced an increase in the rate of muscle protein synthesis (MPS) of ~18%. Maintaining muscle mass is crucial to enjoying a healthy and active lifestyle as adults age. Further, multiple peer-reviewed studies have reported that age-related muscle loss is associated with an increased risk of fall-related injuries. Falls can be devastating, particularly if they result in a bone fracture or a head injury.

“Fortetropin is now backed by seven peer-reviewed publications in reputable scientific journals,” said Mr. Mannello. “The completion of this most recent study at McMaster University represents the completion of MYOS’ third randomized, double blind, placebo-controlled human clinical study on Fortetropin. MYOS remains committed to pursuing rigorous scientific research as we build our Human Nutrition and Animal Health businesses.”

First discovered by researchers in 1997 at Johns Hopkins University, myostatin is a protein that arrests the growth and development of new muscle tissue]. A knockout strain of mice that were lacking myostatin were found to have approximately twice as much muscle mass as regular mice and were later referred as “mighty mice.” Blocking the activity of myostatin or that of its receptor, ActRIIB, using monoclonal antibodies has been a strategy that has been employed by multiple pharmaceutical and biotechnology companies over the last two decades to target musculoskeletal disorders such as sarcopenia and cachexia. Some studies have reported that plasma concentrations of myostatin increase with age.”

MYOS CORP, “The Muscle Company®”, is a Cedar Knolls, NJ-based advanced nutrition company that develops and markets products that improve muscle health and performance. MYOS is the owner of Fortetropin®, a fertilized egg yolk-based product manufactured via a proprietary process to retain and optimize its biological activity. Fortetropin has been clinically shown to increase muscle size, lean body mass and reduce muscle atrophy. MYOS believes Fortetropin has the potential to redefine existing standards of physical health and wellness and produces muscle health support products featuring Fortetropin under the names of Yolked®, MYOS Canine Muscle Formula®, (Regular & Vet Strength) and MYOS Feline Formula. For more information, please visit