Alendronate to Treat Polyostotic Fibrous Dysplasia and McCune-Albright Syndrome
Status:
Completed
Trial end date:
2011-05-02
Target enrollment:
Participant gender:
Summary
This study will evaluate the effectiveness of alendronate in treating the bone abnormality in
polyostotic fibrous dysplasia and McCune-Albright syndrome. In these diseases, areas of
normal bone are replaced with a fibrous growth similar to a scar. The weakened bone causes
pain and increases patients' risk of bone fractures and bone deformities. Alendronate belongs
to a class of drugs called "bisphosphonates," which are approved by the Food and Drug
Administration to treat bone weakening, deformity and pain in other medical conditions. It is
thought that bisphosphonates might work by slowing the activity of osteoclasts-cells that
break down bone.
Patients 12 years of age and older with polyostotic fibrous dysplasia or McCune-Albright
syndrome may be eligible for this 3-year study. Candidates must also be enrolled in NIDCR's
protocol 98-D-0145 (Screening and Natural History of Patients with Polyostotic Fibrous
Dysplasia and McCune-Albright Syndrome).
Participants will be randomly assigned to one of two treatment groups: they will take one
capsule a day of either alendronate or placebo (a look-alike capsule that has no active
ingredient). They will take the capsules for 6 months, stop for 6 months, then take them for
another 6 months and then go off them for 6 months. They will then remain off the drug or
placebo for an additional 12 months and complete the study with a final follow-up visit at 36
months. While taking alendronate or placebo, patients will also take calcium and vitamin D to
prevent secondary hyperparathyroidism-a side effect of alendronate in which the bone does not
release enough calcium.
Patients will come to NIH for a physical examination and blood and urine tests every 6 months
and for monitoring of their bone disease, vision, hearing, pain levels, functional
evaluation, and photographs every 12 months. Many of the monitoring procedures, including
imaging studies and biopsies, are performed for the screening protocol (98-D-0145) and will
not be duplicated for this study. During the study periods when patients are taking
alendronate or placebo, they will have blood samples drawn by their local physician once
every 3 months and sent to NIH to check for secondary hyperparathyroidism.
If at the end of the study alendronate is found to be effective, patients who were in the
placebo treatment group will be offered alendronate for a 24-month period.
Phase:
Phase 2
Details
Lead Sponsor:
National Institute of Dental and Craniofacial Research (NIDCR)