Osteologix, Inc, headquartered in San Francisco, California, announced that its phase I clinical trial of NBS-101, an improved formulation of strontium for the treatment of osteoporosis, has demonstrated that the novel compound is bioequivalent to strontium ranelate at a dose substantially lower than the recently approved European product. 

The trial, conducted at Hvidovre Hospital in Copenhagen, Denmark, was designed to establish both safety and the dose required to deliver the same blood levels of strontium as the 2 g dose of strontium ranelate (Protelos®, Servier), a dual-acting antiosteoporotic treatment recently launched in Europe.  According to Osteologix, the lower dose of NBS-101 should allow for the administration of the compound as a once-a-day oral tablet while delivering the same amount of strontium as Protelos. There were no treatment-related side effects in the study subjects who were given NBS-101. The phase I study also provided clinical evidence that NBS-101 had the dual effect of reducing bone degradation while having a positive effect on bone formation. 

There are currently no US FDA-approved osteoporosis therapies that both increase bone formation and decrease bone resorption. Yet by stimulating osteoblasts and decreasing osteoclasts, strontium ranelate rebalances bone turnover in favor of the formation of new and stronger bone and early and sustained antifracture efficacy. These actions are reflected clinically in the increased bone density and significantly reduced incidence of new vertebral and hip fractures in women with a history of osteoporotic fracture.   

—A. Techman