{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,23]],"date-time":"2026-04-23T04:29:24Z","timestamp":1776918564075,"version":"3.51.2"},"reference-count":4,"publisher":"Wiley","issue":"3","license":[{"start":{"date-parts":[[2021,7,9]],"date-time":"2021-07-09T00:00:00Z","timestamp":1625788800000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by-nc-nd\/4.0\/"}],"content-domain":{"domain":["onlinelibrary.wiley.com"],"crossmark-restriction":true},"short-container-title":["Muscle and Nerve"],"published-print":{"date-parts":[[2021,9]]},"abstract":"<jats:title>Abstract<\/jats:title><jats:sec><jats:title>Introduction\/Aim<\/jats:title><jats:p>Long\u2010term efficacy and safety of dichlorphenamide (DCP) were characterized in patients with primary periodic paralysis (PPP).<\/jats:p><\/jats:sec><jats:sec><jats:title>Methods<\/jats:title><jats:p>Patients with PPP in a double\u2010blind, placebo\u2010controlled study were randomly assigned to receive DCP 50\u2009mg twice daily or placebo for 9\u2009weeks, followed by a 52\u2010week open\u2010label DCP treatment phase (DCP\/DCP and placebo\/DCP populations). Efficacy (attack rate, severity\u2010weighted attack rate) and safety were assessed in patients completing the study (61\u2009weeks). In this post hoc analysis, efficacy and safety data were pooled from hyperkalemic and hypokalemic substudies.<\/jats:p><\/jats:sec><jats:sec><jats:title>Results<\/jats:title><jats:p>Sixty\u2010three adults (age, 19\u201076\u2009years) completed the double\u2010blind phase; 47 (74.6%) of these patients completed 61\u2009weeks. There were median decreases in weekly attack and severity\u2010weighted attack rates from baseline to week 61 (DCP\/DCP [n\u00a0=\u00a025], \u22121.00 [<jats:italic>P<\/jats:italic>\u2009&lt;\u2009.0001]; placebo\/DCP [n\u00a0=\u00a020], \u22120.63 [<jats:italic>P<\/jats:italic>\u00a0=\u00a0.01] and DCP\/DCP, \u22122.25 [<jats:italic>P<\/jats:italic>\u2009&lt;\u2009.0001]; placebo\/DCP, \u22121.69 [<jats:italic>P<\/jats:italic>\u00a0=\u00a0.01]). Relatively smaller median decreases in weekly attack and severity\u2010weighted attack rates occurred from weeks 9 to 61 among patients receiving DCP continuously (n\u00a0=\u00a026; \u22120.14 [<jats:italic>P<\/jats:italic>\u00a0=\u00a0.1] and \u22120.24 [<jats:italic>P<\/jats:italic>\u00a0=\u00a0.09]) than among those switching from placebo to DCP after 9\u2009weeks (n\u00a0=\u00a016; \u22121.04 [<jats:italic>P<\/jats:italic>\u00a0=\u00a0.049] and \u22122.72 [<jats:italic>P<\/jats:italic>\u00a0=\u00a0.08]). Common adverse events (AEs) were paresthesia and cognition\u2010related events, which typically first occurred within 1\u00a0month of blinded treatment initiation and in rare cases led to treatment discontinuation. Dose reductions were frequently associated with common AE resolution.<\/jats:p><\/jats:sec><jats:sec><jats:title>Discussion<\/jats:title><jats:p>One\u2010year open\u2010label DCP treatment after a 9\u2010week randomized, controlled study confirmed long\u2010term DCP remains safe and effective for chronic use. Tolerability issues (paresthesia, cognition\u2010related AEs) were manageable in most patients.<\/jats:p><\/jats:sec>","DOI":"10.1002\/mus.27354","type":"journal-article","created":{"date-parts":[[2021,6,15]],"date-time":"2021-06-15T13:08:21Z","timestamp":1623762501000},"page":"342-346","update-policy":"https:\/\/doi.org\/10.1002\/crossmark_policy","source":"Crossref","is-referenced-by-count":9,"title":["Long\u2010term efficacy and safety of dichlorphenamide for treatment of primary periodic paralysis"],"prefix":"10.1002","volume":"64","author":[{"given":"Valeria A.","family":"Sansone","sequence":"first","affiliation":[{"name":"Neuromuscular Omnicentre, Neurorehabilitation Unit University of Milan, Niguarda Hospital  Milan Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3917-4257","authenticated-orcid":false,"given":"Nicholas E.","family":"Johnson","sequence":"additional","affiliation":[{"name":"Department of Neurology Virginia Commonwealth University  Richmond Virginia USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Michael G.","family":"Hanna","sequence":"additional","affiliation":[{"name":"MRC Centre for Neuromuscular Diseases, Department of Neuromuscular Diseases UCL Institute of Neurology  London UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Emma","family":"Ciafaloni","sequence":"additional","affiliation":[{"name":"Department of Neurology University of Rochester Medical Center  Rochester New York USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0790-5315","authenticated-orcid":false,"given":"Jeffrey M.","family":"Statland","sequence":"additional","affiliation":[{"name":"Department of Neurology University of Kansas Medical Center  Kansas City Kansas USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7145-7663","authenticated-orcid":false,"given":"Perry B.","family":"Shieh","sequence":"additional","affiliation":[{"name":"Department of Neurology Ronald Reagan UCLA Medical Center  Los Angeles California USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Fredric","family":"Cohen","sequence":"additional","affiliation":[{"name":"Strongbridge Biopharma  Trevose Pennsylvania USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Robert C.","family":"Griggs","sequence":"additional","affiliation":[{"name":"Department of Neurology University of Rochester Medical Center  Rochester New York USA"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"311","published-online":{"date-parts":[[2021,7,9]]},"reference":[{"key":"e_1_2_10_2_1","doi-asserted-by":"publisher","DOI":"10.1002\/mus.26009"},{"key":"e_1_2_10_3_1","unstructured":"Keveyis\u00ae(dichlorphenamide) tablets for oral use [package insert]. Trevose PA: Strongbridge US;2019."},{"key":"e_1_2_10_4_1","doi-asserted-by":"publisher","DOI":"10.1002\/1531-8249(200001)47:1<46::AID-ANA9>3.0.CO;2-H"},{"key":"e_1_2_10_5_1","doi-asserted-by":"publisher","DOI":"10.1212\/WNL.0000000000002416"}],"container-title":["Muscle &amp; Nerve"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/pdf\/10.1002\/mus.27354","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/full-xml\/10.1002\/mus.27354","content-type":"application\/xml","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/pdf\/10.1002\/mus.27354","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2023,8,25]],"date-time":"2023-08-25T17:08:04Z","timestamp":1692983284000},"score":1,"resource":{"primary":{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/10.1002\/mus.27354"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2021,7,9]]},"references-count":4,"journal-issue":{"issue":"3","published-print":{"date-parts":[[2021,9]]}},"alternative-id":["10.1002\/mus.27354"],"URL":"https:\/\/doi.org\/10.1002\/mus.27354","archive":["Portico"],"relation":{},"ISSN":["0148-639X","1097-4598"],"issn-type":[{"value":"0148-639X","type":"print"},{"value":"1097-4598","type":"electronic"}],"subject":[],"published":{"date-parts":[[2021,7,9]]},"assertion":[{"value":"2020-07-23","order":0,"name":"received","label":"Received","group":{"name":"publication_history","label":"Publication History"}},{"value":"2021-06-13","order":1,"name":"accepted","label":"Accepted","group":{"name":"publication_history","label":"Publication History"}},{"value":"2021-07-09","order":2,"name":"published","label":"Published","group":{"name":"publication_history","label":"Publication History"}}]}}