J.LeLorier, MD, PhD, Centre de Recherche, Montréal, Québec, Canadajacques.le.lorier@umontreal.ca
M. S. Duh, MPH, ScD, P. E. Paradis, MA, DESS, P. Lefebvre, MA, . Weiner, MPA, R. Manjunath, MSPH and O. Sheehy, MSc
Submitted October 02, 2008
We appreciate Dr. Boylan’s interest in our research and would like to respond to several points raised in her correspondence. [1]
We find Dr. Boylan’s statements about the “controversial” nature of AAN policies, as well as “promotionally driven doctors and patient preferences” speculative. Our research was an observational study that examined the real-world prescribing patterns and measured medical resource utilization in patients with epilepsy treated with AEDs. It would be beyond the scope of our study to investigate the impact of promotional activities on physicians’ prescribing behaviors.
Also, we do not believe that industry promotional activities would be systematically less vigorous or influential in any of the drugs in the three control groups reported in our research relative to anti-epileptics.
Our inclusion criterion was at least one claim for epilepsy, and not “a single claim” as described by Dr. Boylan. Ninety-one percent of our study population had at least two claims for epilepsy, and more than half of the patients received a diagnosis for epilepsy at least 10 times during the observation period. We think this demonstrates that for these subjects, lamotrigine was likely prescribed as an anti-epileptic agent and was not used as a psychiatric treatment.
Two main findings emerged from our study. First, AED users exhibited a higher propensity of switchback to branded drugs compared to patients treated with other chronic-disease drugs. Secondly, the use of generic lamotrigine was associated with increased physician visits and hospitalizations compared to brand use. We do not attribute these results strictly to seizure activity. As we stated, while these findings may signal reduced clinical effectiveness or increased side effects associated with generic lamotrigine use, this study lacked access to data on whether drugs dispensed were actually taken according to prescribed instructions, or on disease severity.
Dr. Boylan’s statement that “anxiety-induced dose escalations contributed to side effects and, in turn, switchbacks” in patients treated with generic lamotrigine could be one of the plausible explanations for the findings.
Disclosure: This study was sponsored by GlaxoSmithKline (GSK), Research Triangle Park, NC. GSK participated in the design, review, and approval of the manuscript. J. LeLorier has a consulting agreement with Analysis Group, Inc. and has received grants from GSK for other research projects in excess of $10,000. M.S. Duh, P.E. Paradis, P. Lefebvre, and J. Weiner are employees of Analysis Group, Inc., which has received research grants from GSK. R. Manjunath is an employee of GSK. O. Sheehy reports no conflict of interest.
We appreciate Dr. Boylan’s interest in our research and would like to respond to several points raised in her correspondence. [1]
We find Dr. Boylan’s statements about the “controversial” nature of AAN policies, as well as “promotionally driven doctors and patient preferences” speculative. Our research was an observational study that examined the real-world prescribing patterns and measured medical resource utilization in patients with epilepsy treated with AEDs. It would be beyond the scope of our study to investigate the impact of promotional activities on physicians’ prescribing behaviors.
Also, we do not believe that industry promotional activities would be systematically less vigorous or influential in any of the drugs in the three control groups reported in our research relative to anti-epileptics.
Our inclusion criterion was at least one claim for epilepsy, and not “a single claim” as described by Dr. Boylan. Ninety-one percent of our study population had at least two claims for epilepsy, and more than half of the patients received a diagnosis for epilepsy at least 10 times during the observation period. We think this demonstrates that for these subjects, lamotrigine was likely prescribed as an anti-epileptic agent and was not used as a psychiatric treatment.
Two main findings emerged from our study. First, AED users exhibited a higher propensity of switchback to branded drugs compared to patients treated with other chronic-disease drugs. Secondly, the use of generic lamotrigine was associated with increased physician visits and hospitalizations compared to brand use. We do not attribute these results strictly to seizure activity. As we stated, while these findings may signal reduced clinical effectiveness or increased side effects associated with generic lamotrigine use, this study lacked access to data on whether drugs dispensed were actually taken according to prescribed instructions, or on disease severity.
Dr. Boylan’s statement that “anxiety-induced dose escalations contributed to side effects and, in turn, switchbacks” in patients treated with generic lamotrigine could be one of the plausible explanations for the findings.
Disclosure: This study was sponsored by GlaxoSmithKline (GSK), Research Triangle Park, NC. GSK participated in the design, review, and approval of the manuscript. J. LeLorier has a consulting agreement with Analysis Group, Inc. and has received grants from GSK for other research projects in excess of $10,000. M.S. Duh, P.E. Paradis, P. Lefebvre, and J. Weiner are employees of Analysis Group, Inc., which has received research grants from GSK. R. Manjunath is an employee of GSK. O. Sheehy reports no conflict of interest.