Oral Option Could Be Game-Changer, But Not Yet
The gold standard of treatment for OSA is a CPAP machine, but the effectiveness is limited by patient tolerance, Q. Afifa Shamim-Uzzaman, MD, an associate professor and a sleep medicine specialist at the University of Michigan, Ann Arbor, said in an interview.
“Presently, there are no effective pharmacological treatments for OSA — having a pill that treats OSA would be a total game changer and huge advance for the treatment of OSA and the field of sleep medicine,” said Dr. Shamim-Uzzaman, who was not involved in the study. “More patients may be able to obtain treatment for OSA and thereby reduce the potential complications of untreated OSA.
“Carbonic anhydrase inhibitors such as acetazolamide and sulthiame have been studied with limited success for the treatment of other forms of sleep disordered breathing such as central sleep apnea [CSA] but have shown less efficacy for OSA and are presently not recommended in the treatment of OSA by the American Academy of Sleep Medicine,” Dr. Shamim-Uzzaman said.
Recently, emerging evidence about different phenotypes of OSA suggests that nonanatomic features (such as high loop gain) may play a role in patients with OSA, not only in those with CSA, she said. Whether carbonic anhydrase inhibitors could play a greater role in treating sleep apnea in patients with predominantly nonanatomic pathophysiologic traits remains to be seen.
The sulthiame data are promising, but more research is needed, Dr. Shamim-Uzzaman said. Although patients in the highest dose group showed a reduction in AHI of nearly 40%, they still would have moderate OSA, and the OSA did not appear to decrease to a normal range in any of the treatment groups.
“More research is needed to identify which types of patients would be responders to this form of therapy, to understand if these effects are maintained long term (beyond 15 weeks), to evaluate patient-centered outcomes, especially in different sleep apnea subgroups (such as phenotypes with high loop gain vs those without), and to assess interactions with other therapies,” she said.
The study was supported by manufacturer Desitin. Dr. Hedner disclosed serving as a consultant to AstraZeneca, Bayer, CereusScience, Jazz Pharmaceuticals, MSD, Weinmann, Desitin, SomnoMed, and Itamar Medical; serving on the speakers’ bureau for Almirall, AstraZeneca, Jazz Pharmaceuticals, ResMed, Philips Respironics, and Weinmann; and receiving grants or research support from Bayer, ResMed, Philips Respironics, and SomnoMed. He also disclosed shared ownership of intellectual property related to sleep apnea therapy. Dr. Shamim-Uzzaman had no financial conflicts to disclose.
A version of this article appeared on Medscape.com.