POSTMARKETING SURVEILLANCE OF THE SAFETY OF CYCLIC ETIDRONATE

To evaluate the safety of cyclic etidronate in routine clinical practi ce, we obtained information from 550 general practices in the United K ingdom that provide the medical records to the General Practice Resear ch Database. A group of 7977 patients taking cyclic etidronate and two age-, gender-, and practice-matched control groups, one with osteopor osis and one without, were analyzed. For the group taking cyclic etidr onate, the average age was 71.6 years and follow-up was 10,328 person- years. Conditions that do not induce osteoporosis generally occurred i n these patients at a rate comparable to that in the control groups. T he incidence of osteomalacia was low and comparable between patients t aking cyclic etidronate and controls with osteoporosis. No medically s ignificant increases in frequency were observed among patients taking cyclic etidronate for a broad group of diseases that may potentially b e induced by exposure to the drug. These data support the favorable ri sk:benefit ratio of cyclic etidronate.