LGD-3303 is a selective androgen receptor full agonist in skeletal muscle, a target tissue for androgen action. By comparison, in the prostate and sebaceous glands, the compound is a weak partial agonist. The sparing of these non-target tissues by effective, pharmacologic doses of LGD-3303 provides a novel and potentially safer treatment for osteoporosis.
Martin Meglasson, vice president of discovery research, described the following key findings in this study: Repeated oral doses of LGD-3303 were more effective than alendronate (Fosamax) for increasing bone mineral density in the femur. The mechanism for the increased bone mineral density was shown to be the deposition of new bone. In the lumbar spine, LGD-3303 was as effective as aldendronate in increasing bone mineral density. The combination of LGD-3303 and alendronate was more effective than either treatment alone at increasing lumbar bone mineral density. LGD-3303 increased the bone strength of both the femur and spine.
Findings suggest the potential for LGD-3303 to be useful either as a single agent or in combination with conventional bisphosphonate therapy. The data suggest that LGD-3303 may provide a safe and effective new drug for the treatment of osteoporosis, including in patients that have had an inadequate response to bisphosphonate treatment.