Ostarine
Encyclopedia
Ostarine (also known as GTx-024 and MK-2866) is an investigational selective androgen receptor modulator
(SARM) from GTX, Inc for treatment of conditions such as muscle
wasting and osteoporosis
, formerly under development by Merck & Company.
. The chemical structure of Ostarine has not been publicly disclosed." While GTx has not formally disclosed the structure of Ostarine, the chemical composition of Ostarine is revealed in patent databases such the WIPO and discussed by Zhang et al., 2009 in the primary literature. Various SARM chemotypes exist (aryl propionamides, quinolines, quinolinones, bicyclic hydantoins), though aryl propionamides such as Ostarine, Andarine/S-4, and S-23 represent some of the most advanced putative therapeutics under investigation. In terms of atom connectivity, Ostarine differs from Andarine by cyano substitutions on the phenyl rings as it replaces both the nitro and acetamido moieties.
in 120 subjects (60 elderly men and 60 postmenopausal women). Ostarine treatment resulted in a dose-dependent increase in lean body mass
(LBM), with those taking the highest dose of 3mg/kg per day showing an average LBM increase of 1.4 kg (3.1 lbs) compared to those who received placebo
. The Ostarine treatment also resulted in improvement in muscle function (performance) in a 12 stair climb test measuring speed and power. Ostarine had a favorable safety profile, with no serious adverse events reported. Ostarine also exhibited tissue selectivity with beneficial effects on lean body mass and performance and with no apparent change in measurements of serum PSA, sebum production or serum LH
.
In October 2008, GTx announced topline results of the Phase II trial evaluating Ostarine in patients with cancer cachexia
. The clinical trial enrolled 159 cancer patients (average age of 66 years) with non-small cell lung cancer, colorectal cancer, non-Hodgkin lymphoma, chronic lymphocytic leukemia or breast cancer at 35 sites in the U.S. and Argentina. Participants were randomized to receive placebo, 1mg/kg or 3mg/kg oral capsule of Ostarine once daily for 16 weeks. Average reported weight loss prior to entry among all subjects was 8.8%. Subjects were allowed to have standard chemotherapy during the trial. The study met its primary endpoint of absolute change in total lean body mass (muscle) compared to placebo and the secondary endpoint of muscle function (performance). The incidence of serious adverse events, deaths and tumor progression were similar among placebo and the treatment arms. The most common side effects reported among all subjects in the trial were fatigue, anemia, nausea and diarrhea.
GTx and Merck had clinical development plans to evaluate Ostarine for the treatment of muscle loss in patients with COPD and for the treatment of chronic sarcopenia
. They had a goal of initiating an Ostarine Phase II COPD clinical trial in the first quarter of 2010 and an Ostarine Phase IIb chronic sarcopenia clinical trial in 2010.
http://upload.wikimedia.org/wikipedia/commons/5/51/2010-04-23_Ostarine_vs_Andarine.TIF
Selective androgen receptor modulator
Selective androgen receptor modulators or SARMs are a novel class of androgen receptor ligands. They are intended to have the same kind of effects as androgenic drugs like anabolic steroids but be much more selective in...
(SARM) from GTX, Inc for treatment of conditions such as muscle
Muscle
Muscle is a contractile tissue of animals and is derived from the mesodermal layer of embryonic germ cells. Muscle cells contain contractile filaments that move past each other and change the size of the cell. They are classified as skeletal, cardiac, or smooth muscles. Their function is to...
wasting and osteoporosis
Osteoporosis
Osteoporosis is a disease of bones that leads to an increased risk of fracture. In osteoporosis the bone mineral density is reduced, bone microarchitecture is deteriorating, and the amount and variety of proteins in bone is altered...
, formerly under development by Merck & Company.
Structure
According to a recent paper authored by GTx, "Readers are cautioned to note that the name Ostarine is often mistakenly linked to the chemical structure of [S-4], which is also known as andarineAndarine
Andarine is an investigational selective androgen receptor modulator developed by GTX, Inc for treatment of conditions such as muscle wasting, osteoporosis and benign prostatic hypertrophy, using the non-steroidal androgen antagonist bicalutamide as a lead compound.Andarine is an orally active...
. The chemical structure of Ostarine has not been publicly disclosed." While GTx has not formally disclosed the structure of Ostarine, the chemical composition of Ostarine is revealed in patent databases such the WIPO and discussed by Zhang et al., 2009 in the primary literature. Various SARM chemotypes exist (aryl propionamides, quinolines, quinolinones, bicyclic hydantoins), though aryl propionamides such as Ostarine, Andarine/S-4, and S-23 represent some of the most advanced putative therapeutics under investigation. In terms of atom connectivity, Ostarine differs from Andarine by cyano substitutions on the phenyl rings as it replaces both the nitro and acetamido moieties.
Clinical trials
In December 2006, GTx completed a 3 month Phase II double-blind, randomized, placebo-controlled clinical trialClinical trial
Clinical trials are a set of procedures in medical research and drug development that are conducted to allow safety and efficacy data to be collected for health interventions...
in 120 subjects (60 elderly men and 60 postmenopausal women). Ostarine treatment resulted in a dose-dependent increase in lean body mass
Body composition
In physical fitness, body composition is used to describe the percentages of fat, bone and muscle in human bodies. Because muscular tissue takes up less space in our body than fat tissue, our body composition, as well as our weight, determines leanness...
(LBM), with those taking the highest dose of 3mg/kg per day showing an average LBM increase of 1.4 kg (3.1 lbs) compared to those who received placebo
Placebo
A placebo is a simulated or otherwise medically ineffectual treatment for a disease or other medical condition intended to deceive the recipient...
. The Ostarine treatment also resulted in improvement in muscle function (performance) in a 12 stair climb test measuring speed and power. Ostarine had a favorable safety profile, with no serious adverse events reported. Ostarine also exhibited tissue selectivity with beneficial effects on lean body mass and performance and with no apparent change in measurements of serum PSA, sebum production or serum LH
Luteinizing hormone
Luteinizing hormone is a hormone produced by the anterior pituitary gland. In females, an acute rise of LH called the LH surge triggers ovulation and development of the corpus luteum. In males, where LH had also been called interstitial cell-stimulating hormone , it stimulates Leydig cell...
.
In October 2008, GTx announced topline results of the Phase II trial evaluating Ostarine in patients with cancer cachexia
Cachexia
Cachexia or wasting syndrome is loss of weight, muscle atrophy, fatigue, weakness, and significant loss of appetite in someone who is not actively trying to lose weight...
. The clinical trial enrolled 159 cancer patients (average age of 66 years) with non-small cell lung cancer, colorectal cancer, non-Hodgkin lymphoma, chronic lymphocytic leukemia or breast cancer at 35 sites in the U.S. and Argentina. Participants were randomized to receive placebo, 1mg/kg or 3mg/kg oral capsule of Ostarine once daily for 16 weeks. Average reported weight loss prior to entry among all subjects was 8.8%. Subjects were allowed to have standard chemotherapy during the trial. The study met its primary endpoint of absolute change in total lean body mass (muscle) compared to placebo and the secondary endpoint of muscle function (performance). The incidence of serious adverse events, deaths and tumor progression were similar among placebo and the treatment arms. The most common side effects reported among all subjects in the trial were fatigue, anemia, nausea and diarrhea.
GTx and Merck had clinical development plans to evaluate Ostarine for the treatment of muscle loss in patients with COPD and for the treatment of chronic sarcopenia
Sarcopenia
Sarcopenia is the degenerative loss of skeletal muscle mass and strength associated with aging...
. They had a goal of initiating an Ostarine Phase II COPD clinical trial in the first quarter of 2010 and an Ostarine Phase IIb chronic sarcopenia clinical trial in 2010.
http://upload.wikimedia.org/wikipedia/commons/5/51/2010-04-23_Ostarine_vs_Andarine.TIF