An intravenous (I.V.) injection of the new bisphosphonate Bonviva (ibandronate sodium), given either once every two or three months, has been shown to be effective at treating post-menopausal osteoporosis. Given this dosing flexibility, Bonviva has the potential to be the first bisphosphonate to offer effective treatment from both once-monthly oral and I.V. intermittent dosage regimens, according to a study reported at the annual meeting of the American College of Rheumatology in San Antonio, US.

The study showed that an I.V. injection of Bonviva given once every two or three months was at least as effective as the previously approved once-daily oral formulation in increasing spine bone mineral density (BMD) in women with post-menopausal osteoporosis. Both IV regimens produced superior increases in lumbar spine BMD compared to the once daily oral formulation.

Dosing by intravenous injection is predicted to provide advantages to patients who currently do not tolerate or cannot comply with oral therapy. The marketing application for this I.V. formulation will be submitted to the regulatory authorities in the near future.

"These findings are important because they show that Bonviva has potential for an I.V. dosing regimen, that may be a more convenient treatment option for many patients", said lead investigator Robert Recker, chief of Endocrinology and Director of the Osteoporosis Research Centre at the
Creighton University School of Medicine in Omaha, Neb. "I.V. administration provides a treatment option for osteoporosis not previously available with oral bisphosphonates," Dr. Recker added.

A once-daily oral formulation of ibandronate was approved in the US in May 2003 and in Europe in February 2004. Roche and GlaxoSmithKline are not marketing the daily dose but have been exploring less frequent dosing regimens before launching the product. A supplemental new drug application (sNDA) for a once-monthly oral regimen of the product for the treatment and prevention of postmenopausal osteoporosis was submitted to the FDA in May 2004. An MAA for the once-monthly regimen for the treatment of postmenopausal osteoporosis was submitted to the European authorities in September 2004.

Bonviva, a potent bisphosphonate, has been studied to date in clinical trials involving over 9,000 patients. Once daily Bonviva is indicated for the treatment and prevention of osteoporosis in postmenopausal women by reducing elevated bone turnover, increasing bone mineral density and reducing the incidence of vertebral fractures.

In December 2001, Roche and GSK announced that they would co-develop and co-promote Bonviva for the treatment and prevention of postmenopausal osteoporosis in all countries, except Japan. The Roche/GSK collaboration provides expertise and commitment to bring new osteoporosis therapies to market as quickly as possible.