Bisphosphonate treatment in osteogenesis imperfecta: which drug, for whom, for how long?

Treatment with bisphosphonates has brought significant clinical improvements for children and adolescents suffering from moderate to severe forms of osteogenesis imperfecta (OI). Benefits include decreased pain, lower fracture incidence, and better mobility. Among the various bisphosphonates, intravenous pamidronate has been studied in most detail. It is unclear whether oral bisphosphonates are as effective as intravenous pamidronate. As the effect of bisphosphonates on the skeleton is largest during growth, it appears logical to start medical therapy of OI patients as early as possible. Nevertheless, the optimal treatment regimen and the long-term consequences of pamidronate treatment in children are currently unknown. Given these uncertainties, treatment with bisphosphonates should be reserved for patients who have significant clinical problems, such as vertebral compression fractures or long bone deformities. At present, bisphosphonate treatment has little justification in growing patients with mild forms of OI who have few or no clinical symptoms. Such patients should not be treated unless clear clinical benefit can be demonstrated in ongoing placebo-controlled trials.