Study Suggests that Response to Bisphosphonates Correlates with Vitamin D Levels
Research presented at the American Society for Bone and Mineral Research (ASBMR) 2011 Annual Meeting suggests that osteoporosis patients with high Vitamin D levels are significantly more likely to respond to bisphosphonate therapy. This is important news for users because of bisphosphonates’ alleged tendency to cause atypical bone breaks as described in this Fosamax infographic.
What Does the Study Show?
The results were based on a study that evaluated 210 postmenopausal women in New York City with an average age of 65 and low bone mineral density. All of the women had taken bisphosphonates, a category of bone-strengthening drugs that includes Fosamax, for roughly five years, and had their vitamin D intake followed for at least 18 months. Those with vitamin D blood serum levels beyond 33 ng/mL were up to 4.5 times more likely to respond favorably to bisphosphonates.
According to the authors, “The current study is the first to identify a threshold level of 25(OH)D that defines improved outcome to bisphosphonate therapy such that patients with a mean 25(OH)D ≥ 33 ng/mL had a substantially greater likelihood of responding to bisphosphonates.”
Furthermore, the findings may offer an explanation of why bisphosphonate clinical trials show the drugs to be more effective than they are in the real world.
Dr. Richard S. Bockman, a Cornell University medical professor and co-author of the study said that, “‘Real world’ patients have not been observed to respond to bisphosphonates at rates comparable to those seen in clinical trials.” Dr. Bockman believes this may be because “there is a high prevalence of low 25(OH)D levels among ‘real world’ patients taking bisphosphonates.”
It is typical in bisphosphonate drug trials for participants to take vitamin D supplements.
Long-Term Bisphosphonate Effectiveness Recently Scrutinized by FDA
The study presented at the ASBMR annual meeting shows that of the 210 women, 99 (47 percent) had responded well to prolonged bisphosphonate therapy.
This seems to correspond to the belief of some medical professionals that prolonged bisphosphonate use is not only non-beneficial, but could in fact increase a user’s chance of suffering a bone injury.
When asked during a September 9 meeting whether bisphosphonate labels should “further clarify the duration of use,” two advisory committees to the Food and Drug Administration (FDA) agreed by a margin of 17-6 that they should. The meeting was scheduled by the FDA amidst an increasing number of Fosamax lawsuits against manufacturer Merck & Co. over the drug’s alleged ability to cause bone injuries such as osteonecrosis of the jaw (ONJ) and atypical femur fractures.
Contact RLG to Discuss a Potential Fosamax Lawsuit
If you believe that Fosamax caused your thigh bone break, you may have cause to take legal action against Merck & Co. A free consultation with a member of the Rottenstein Law Group will determine the viability of your claim, including whether you may qualify for compensation through a Fosamax settlement. To speak with a lawyer, fill out this contact form or call 1-877-332-2347.
