Datamonitor attended this year’s International Osteoporosis Foundation World Congress on Osteoporosis and 10th European Congress on Clinical and Economical Aspects of Osteoporosis and Osteoarthritis, the most important meeting on the osteoporosis calendar. A number of major pharmaceutical firms had a presence at the meeting, indicating the significance of this market.
Pfizer: remains a small presence in the osteoporosis marketThe presence of Pfizer at the congress suggests that the company intends to launch Conbriza (bazedoxifene) in the European market after it was approved in 2009. It is Datamonitor’s understanding that the company is negotiating price and reimbursement issues prior to launching the drug, possibly by the end of the year. On the other hand, Pfizer’s other drug Fablyn (lasofoxifene) was not mentioned at the congress, reinforcing Datamonitor’s opinion that Pfizer itself will never launch the drug.Conbriza - also known as Viviant in the US - is a novel once-daily oral selective estrogen receptor modulator (SERM) developed by Pfizer for the treatment of postmenopausal osteoporosis. Conbriza was approved by the European Medicines Agency (EMA) in April 2009, but has not yet launched and is currently being reviewed by the FDA for the same indication. Conbriza was also filed in Japan in 2007.There have been several safety and efficacy issued with the use of SERMs for osteoporosis which have resulted in the recent decrease in sales of the only drug in this class on the market, Eli Lilly’s Evista (raloxifene). Pfizer made an effort to improve the clinical attractiveness of its drug at the congress by presenting several posters analyzing gynecological, cardiovascular and breast safety after five years of treatment. However, it remains unclear if this will be sufficient to convince the FDA regarding Conbriza’s safety. Pfizer also presented a two-year extension to the three-year pivotal trial for bazedoxifene. Importantly, the study showed efficacy of bazedoxifene in preventing non-vertebral fractures in women with severe osteoporosis. However, In Datamonitor’s opinion these data were not very solid and Conbriza’s efficacy in preventing non-vertebral fracture among all women in the trial was statistically insignificant. As new therapies reach the market, Datamonitor believes that physicians remain skeptical of the use of these drugs for the treatment of osteoporosis.Sanofi-Aventis/Warner Chilcott: alliance for better bone health presents GLOW resultsSanofi-Aventis has been marketing the leading brand Actonel (risedronate) in the US since its launch a decade ago. At the congress, alongside its new partner Warner Chilcott, the French pharmaceutical giant provided data from the GLOW study (Global Longitudinal Study of Osteoporosis in Women). GLOW is a prospective study involving over 60,000 women in the US, Canada, Europe and Australia. Group analysis showed that in Northern Europe only 13% of women involved were using anti-osteoporosis medications, while in the US and Canada up to 32% of women were treated. The percentage of diagnosed and treated women was also the lowest in Europe (45-52%) compared to the other regions (62-65%). The study also showed that women in the US were three times more likely to be treated than women in Southern Europe.Out of the 5,321 women in GLOW who were taking osteoporosis drugs at baseline, 19% had stopped after the first year. The most common reason was due to doctor’s advice (37%) or side effects or long-term risk concerns (37%). No particular differences were seen in the discontinuation patterns and reasons among women who were taking bisphosphonates or non-bisphosphonate drugs. Datamonitor believes that this is a very interesting study which will allow researchers to better understand the behavior of women in taking the osteoporosis medications.GlaxoSmithKline: displays continued interest in the osteoporosis marketGlaxoSmithKline’s presence at the conference demonstrated its continued commitment to osteoporosis. Together with its partners Amgen and Roche, it hosted key lunch symposia on denosumab and Bonviva. The company also presented data regarding its calcilytic compound ronacaleret, which recently failed Phase II trails.Investigation of ronacaleret was terminated after Phase II trials failed to show efficacy of the compound in increasing bone mineral density (BMD). The calcium-sensing receptor in parathyroid cells regulates the secretion of parathyroid hormone (PTH). By antagonizing the receptor it was thought that there would be an increase in PTH secretion and therefore an increase in BMD.The Phase II data presented were from a dose finding study (100mg, 200mg, 300mg or 400mg) and included an active comparator (alendronate 70mg) and an open label teriparatide arm. It was seen that patients taking ronacaleret had experienced an increase in lumbar spine BMD but this was lower than what was seen in patients taking alendronate and teriparatide. The authors suggest that ronacaleret caused a mild sustained primary hyperparathyroidism and did not produce the anabolic effect that had been anticipated from preclinical trials.Datamonitor notes that there are several other similar compounds in development for the treatment of osteoporosis. The negative data presented at the conference could suggest that there is a class issue with these novel compounds and therefore they may never reach the market. Nevertheless, experts at the congress are still very intrigued by the compounds and believe that others may be more efficacious in increasing BMD. As such, Datamonitor believes that calcilytic compounds remain attractive therapeutic targets for the time being.Related research• Pipeline And Commercial Insight: Osteoporosis - Novel Agents To Battle For Payer Acceptance
