Zosano’s lead clinical program is ready for Phase 3. ZP-PTH rapid delivery patch for the treatment of severe osteoporosis is being developed as an alternative to daily injections. The product delivers PTH 1-34, teriparatide (PTH), a compound that stimulates formation of new bone and reduces the risk of fractures. The ZP PTH product has also demonstrated greater than 2 year shelf-life without the need for refrigeration.
The majority of products currently available for the treatment of osteoporosis are bisphosphonates, or anti-resorptive compounds which have been shown only to prevent future bone loss. Anabolic compounds like PTH have been shown to stimulate formation of new bone and present a significant opportunity for improved patient care. Currently, PTH is available to patients via daily injections.
Zosano is pursuing a 505(b)(2) regulatory strategy that leverages existing PTH safety and efficacy data of the marketed product Forteo®. Unlike Forteo® the ZP-PTH patch is needle-free patch that requires no refrigeration and demonstrated excellent safety and efficacy through Phase II.
Clinical Pharmacokinetic StudiesIn Clinical studies, the ZP-PTH patch demonstrates rapid drug absorption with a short patch wear time.
Phase 2 Study Demonstrated Increases in Lumbar Spine Bone Mineral Density
A Phase 2 study was performed in 15 centers in three countries and enrolled 165 postmenopausal women aged 50-81 who had been diagnosed with osteoporosis.
Phase 2 clinical results for ZP-PTH demonstrated that daily administration for 24 weeks of the ZP-PTH 40 mcg patch, which delivers an effective dose of PTH, and was comparable to the Forteo® 20 mcg injection, in mean percent change from baseline in lumbar spine BMD (4.97% versus 3.55%). The same study also demonstrated that ZP-PTH 40 mcg showed a significant increase in total hip mean percent change from baseline in BMD (+1.33%) compared to placebo (-0.634%) and Forteo® (0.094%), both at p<0.05 (Figure 2). This observation was an unexpected and positive result which is consistent with our unique rapid on-off pharmacokinetic (PK) profile. All ZP-PTH doses were well tolerated with no systemic adverse events different from Forteo® and there were no clinically significant sustained occurrences of hypercalcemia in any treatment group.
Osteoporosis is a disease characterized by low bone mass and the deterioration of bone tissue, leading to bone fragility and an increased susceptibility to fractures. While any bone can be affected, fractures of the hip, spine and wrist are especially common. According to the National Osteoporosis Foundation, osteoporosis is a major public health issue, affecting 55% of people 50 years or older in the U.S. Approximately 80% of those affected are women. By 2025, experts predict that osteoporosis-related fractures will be responsible for an estimated $25.3 billion in medical costs, an economic burden comparable to other major chronic diseases.