Monthly bisphosphonate holds its own at 2 years.(Gynecology)

VIENNA -- Oral ibandronate at 150 mg once monthly showed continued impressive therapeutic efficacy in women with postmenopausal osteoporosis at the 2-year mark in the Monthly Oral Ibandronate in Ladies (MOBILE) trial, Pierre D. Delmas, M.D., said at the annual European congress of rheumatology.

Ibandronate (Boniva) was approved by the Food and Drug Administration this spring as the first once-monthly oral bisphosphonate, in part because of the persuasive 1-year results of MOBILE.

The new 2-year data provide reassurance that over the longer term this therapy continues to be a highly effective and well-tolerated alternative to daily or weekly bisphosphonates, said Dr. Delmas, professor of medicine and rheumatology at Claude Bernard University, Lyon, France.

MOBILE is a randomized, double-blind, phase III, Roche- and GlaxoSmithKline-sponsored clinical trial involving 1,609 women with postmenopausal osteoporosis who were placed on oral ibandronate at 2.5 mg/day, 100 mg once per month, 150 mg once per month, or 50 mg on each of two consecutive days per month.

The daily-therapy arm served as the comparator group in this trial because 2.5 mg/day was the first FDA-approved ibandronate regimen, and it was previously shown to reduce vertebral fracture risk by 62% compared with placebo in a 3-year trial. Dr. Delmas focused on the once-monthly 150-mg group because this dosage showed the greatest efficacy and is already approved in the United States.

MOBILE wasn't designed or powered to evaluate fracture risk. Instead, it was a bridging trial that relied upon the surrogate end points of change in bone mineral density (BMD) and bone resorption markers in an effort to establish that monthly therapy was noninferior to the 2.5 ...