ZELOS ANNOUNCES RESULTS OF OSTEOPOROSIS TRIAL

Zelos Therapeutics has announced top-line results from a Phase II study of its novel parathyroid hormone (PTH) analogue, Ostabolin-C, in postmenopausal women with osteoporosis. Ostabolin-C contians cyclic PTH, a proprietary PTH analogue that has demonstrated strong bone-building activity in preclinical studies and is in late-stage clinical development for the treatment of osteoporosis.

The Phase II double-blind, placebo-controlled, dose-ranging study enrolled 261 postmenopausal women with moderate osteoporosis into five dose groups. Treatment was continued for four months. The primary endpoint of the study was the percentage change in lumbar spine bone mineral density. All study subjects were offered the opportunity to continue treatment in an eight-month blinded extension to allow the evaluation of 12 months of continuous treatment with Ostabolin-C.

The treatment met the primary objective by demonstrating a highly statistically significant, dose-responsive increase in mean lumbar spine bone mineral density, reaching 5.2 percent at the highest dose tested. Also, the drug was generally well tolerated. The most common adverse events in the study were similar to those seen with other PTH analogs, namely nausea and headache. Mild hypercalcemia was observed at the highest dose tested, but at other doses that also demonstrated strong bone-building activity, the incidence of hypercalcemia was similar to the placebo group.

Preclinical and Phase I studies have shown that Ostabolin-C stimulates significant bone formation with little to no stimulation of bone resorption. Due to the minimized bone resorption, Ostabolin-C has the potential for enhanced efficacy but with reduced potential to cause hypercalcemia, a common side effect of current PTH therapies. With this profile, Ostabolin-C may become a best-in-class compound in the growing PTH market and a leading therapy for the treatment of osteoporosis, according to Zelos.