"The study is continuing out to 12 months, and at 6 months the preliminary data so far are showing sustained positive improvements in all measures of quality of life, reduction of sweat, and impact on daily living," Dr. Lupin said in an interview. Many patients also reported reduction of axillary hair, and a few patients noted improvement in odor, he said.
Overall, patient satisfaction, as measured by the Dermatology Life Quality Index (DLQI), was 96% at 3 months.
When Dr. Lupin was asked whether miraDry had any disadvantages compared with botulinum toxin type A, he said that there are several short-term advantages to botulinum toxin type A: It is a quicker and easier procedure (about 5-10 minutes) with sweat reduction occurring in just a few days, versus 1 hour for the miraDry procedure, which requires anesthesia and can take a week or longer to produce results. Moreover, botulinum toxin type A is a single treatment and its benefit lasts about 6-8 months, whereas miraDry takes 1-3 sessions for a benefit of at least a year and possibly longer.
Indeed, Dr. Kilmer said in an interview, duration of benefit is an advantage of miraDry over just about every current hyperhidrosis treatment other than sympathectomy, a procedure that is rarely done. So far, the longest miraDry has been studied is 12 months, so "we can’t say for sure, but it didn’t drop off much during that time, so we expect it will last much longer," she said.
Dr. Mathew Avram, director of the Massachusetts General Hospital Dermatology Laser and Cosmetic Center, Boston, said, "This is innovative and interesting technology to address an issue that is very problematic for patients. We need to learn a little more about the duration of these benefits and what if any side effects may be created with repeated treatments over time."
The studies were sponsored by Miramar Labs. Dr. Lupin disclosed that he received a research grant for the study and travel expenses from Miramar, and also received honoraria and travel expenses from Allergan. Dr. Kilmer disclosed that she received research support from Miramar. Dr. Avram is a stockholder in Zeltiq.