[Bisphosphonate therapy of Paget's disease of bone with pamidronate]

Paget's disease of bone is a disease with massive focal increase of bone turnover. Bisphosphonates like etidronate inhibit of osteoclastic bone resorption and are therefore established in the treatment of Paget's disease. The aminobisphosphonate pamidronate is 100 times more potent than etidronate. To assess the therapeutic potential for Paget's disease, we have investigated the long-term efficacy of two different dosages of pamidronate.

40 consecutive patients with Paget's disease received a total dose of either 180 mg (n = 21) or 100 mg (n = 19) of pamidronate i.v. over 9 or 5 days respectively in two independent phases of a prospective trial. Efficacy and side effects were monitored for a follow up period of up to two years.

For both dosages a significant reduction of urinary 24-h-hydroxyprolin excretion and serum alkaline phosphatase (AP) levels as parameters of disease activity was recorded. AP levels fell to a minimum of 31 +/- 3% (180 mg) and 41 +/- 5% (100 mg) of pretreatment values, respectively. Two years after treatment, a significant reduction of disease activity could still be detected. Side effects, including transient fever, head ache or bone pain occurred in one third of the patients.

Pamidronate treatment for Paget's disease of bone leads to a sustained inhibition of elevated bone turnover.