News from NAMS 2017: “Bisphosphonate drug holiday” not mandatory

A presentation at the North American Menopause Society (NAMS) Annual Meeting in Philadelphia October 11-14, will  present new evidence regarding long term safety and effectiveness of Bisphosphonates and denosumab in treating postmenopausal osteoporosis.

According to International Osteoporosis Foundation, Osteoporosis is estimated to affect 200 million women worldwide - approximately one-tenth of women aged 60, one-fifth of women aged 70, two-fifths of women aged 80 and two-thirds of women aged 90.

Bisphosphonates and denosumab are the most commonly prescribed treatments for osteoporosis. There is no cure for osteoporosis and the effects of these drugs wear-off as treatment ceases, hence prevention is the best bet.

As Bisphosphonates therapy is started, protection from osteoporosis is gained in first few months and persists as long as treatment is continued.

If Bisphosphonate treatment is continued beyond 3 years, increasing risk of unusual or “atypical” fractures of the femur (thigh bone) is observed. The risk increases gradually as patient continue to take the drug beyond 3 years: the risk is 20/100,000 patients at 5 years and 1/1,000 patients at 8-10 years.

If the drug is stopped, protection from fractures is lost gradually in 3-5 years.

This combination of increased risk of atypical fractures on continued treatment and decline in protection from fractures as treatment is stopped led to the confusing concept of a “bisphosphonate holiday.”

The American Society for Bone and Mineral Research (ASBMR) has recently provided clear recommendations about “bisphosphonate holidays.”

ASBMR recommends that, after 3-5 years of treatment with bisphosphonates, a patient risk of fracture should be evaluated. If the patient remains at ‘high risk’ for fracture because of low BMD, previous history of hip, spine, or multiple other fractures, the treatment should not be stopped.

Patient can continue the same treatment or change to some other drugs like denosumab.

Those patients who are at ‘low risk’ for fracture, the treatment can be stopped for 3-4 years, but it is not mandatory.

The concept of ‘drug holiday’ only holds good for Bisphosphonates only, and not for other drugs like raloxifene, teriparatide, and denosumab because beneficial effects of these drugs are lost as soon as they are stopped.

Dr. Michael McClung of the Oregon Osteoporosis Center in Portland, Oregon, who will be presenting his recommendations on long-term osteoporosis therapy at the NAMS Annual Meeting said, “Because protection from fractures disappears quickly if denosumab treatment is stopped, and since there are no currently known safety issues that limit the duration of denosumab therapy, there is no justification for a drug holiday with this treatment.”

“Just as we do not recommend stopping treatment for high blood pressure or diabetes, it is necessary to have a long-term treatment plan for postmenopausal women with osteoporosis if the benefits of our therapies are to be realized,” he further added.

Dr. JoAnn Pinkerton, NAMS executive director said, “Prevention of osteoporosis should be a goal for those treating menopausal women, as up to 20% of bone loss occurs within the first five years of menopause. Once diagnosed with osteoporosis, the goal becomes lowering the risk of fractures as fractures can be life changing or life limiting. This presentation will offer valuable insights about the need for long-term treatment and will change the way health care providers approach long-term osteoporosis management.”