FDA Response on Midodrine Availability and Effectiveness
The U.S. Food and Drug Administration (FDA) responded to a Heart Rhythm Society letter regarding consumer access to the drug Midodrine Hydrochloride on October 4, 2010. The FDA's response included a clarification of its decision as well as an announcement that there will be a public hearing for the drug manufacturers to present clinical evidence. Read FDA Response » (PDF 86K)
Over the next several months, the FDA will collect additional data, while maintaining consumer access to the drug throughout the data-collecting process. The FDA also accepted the Society's offer to provide data and analysis of the clinical benefits of midodrine hydrochloride
An Excerpt from the FDA letter:
“....want to assure you that we are working with manufacturers of the medication to facilitate its continued availability. Toward that end, we look forward to discussions with organizations that may be able to identify, or have access to, prior studies that verify and describe midodrine's clinical benefit. We are also interested in discussions that could assist the development of new clinical data, for example, by identifying suitable volunteer test subjects. FDA will soon announce in the Federal Register the opening of a public docket that will serve as a forum to facilitate communication regarding the conduct of clinical trials needed to verify and describe the clinical benefit of midodrine when used to treat symptomatic orthstatic hypotension. Additionally, I will contact you directly to discuss whether the Heart Rhythm Society may have information to share or may be willing to assist anyone planning to conduct the needed clinical trials.”
Background
On August 16, 2010, the Food and Drug Administration proposed to withdraw approval of the drug midodrine hydrochloride because neither the original manufacturer nor any generic manufacturer had provided data on the drug's clinical benefit. Midodrine Hydrochoride was originally approved in 1996 under an accelerated approval process. Under this process, a drug company may obtain approval of a drug used to treat a serious or life-threatening disease or condition based upon a "surrogate" endpoint. A surrogate endpoint is a clinical marker, such as a positive effect on blood pressure, believed to predict actual clinical benefits such as improved survival or decreased severity of the disease. See FDA press release »
The Society argued that, while manufacturers failed to meet the requirement for post market studies, there were several reasons to avoid a hasty remove of the drug from the market. First, the FDA has not identified any safety or effectiveness problems with the midodrine hydrochloride. Second, there is no equivalent medication that can be substituted for Midodrine Hydrochloride; and third, in addition to the 100,000 patients who are currently receiving this drug for orthostatic hypotension, the drug has been used for treat syncope, dialysis induced hypotension, and blood pressure variation from astronauts returning from outer space. Read Society Letter » (PDF 113 K)
