FT. LAUDERDALE, FLA. — Bisphosphonate treatment is often extended beyond the duration recommended by the label in patients with Paget's disease of bone, Mohamed Omar, Ph.D., and his associates reported in a poster at a meeting sponsored by the Paget Foundation for Paget's Disease of Bone and Related Disorders.
Paget's disease is the second most common bone disorder among elderly persons, after osteoporosis; about 70–90% of patients are asymptomatic and diagnoses are typically made from incidental findings of elevated lab values or radiographic abnormalities. Bisphosphonates are the standard treatment, said Dr. Omar, of Novartis Pharmaceuticals Corp., East Hanover, N.J., and his associates.
For patients diagnosed with the disease, risedronate therapy is recommended for 2 months and alendronate and etidronate for 6 months. After the recommended treatment course, patients should be evaluated to determine whether they need retreatment. Claims data from a large nationally representative health care database were reviewed for the years 1996–2004. At least one prescription for a bisphosphonate had been written for 433 Paget's disease patients (mean age 65 years, 64.3% female). None had osteoporosis, which would require ongoing bisphosphonate therapy. One-third (33.9%) had been prescribed by general practitioners/internists, followed by endocrinologists (12.5%) and rheumatologists (9.8%).
The most frequently prescribed bisphosphonates were alendronate (53%), followed by risedronate (35%) and etidronate (7%). Additional use, defined as receipt of medication after the recommended treatment regimen for each product's approved label, was most often seen with alendronate (45%), followed by risedronate (41%), and etidronate (18%).
Among the patients with additional use, those taking etidronate had the highest number of mean incremental days' supply (143), followed by risedronate (142), and alendronate (139). Incremental costs of those additional supplies were $995 for those on etidronate, $2,697 for risendronate, and $828 for alendronate, Dr. Omar noted. It's not clear whether increased use of drug therapy reflected a true need for retreatment or inappropriate prescribing, he said.
Novartis is the maker of zoledronic acid, a bisphosphonate under consideration by the Food and Drug Administration for the treatment of Paget's disease.