Strongbridge Biopharma plc announced that post hoc analyses from a one year open-label study evaluating daily use of KEVEYIS® (dichlorphenamide) for the treatment of Primary Periodic Paralysis (PPP) following a nine-week randomized, controlled study were published in the peer-reviewed journal, Muscle & Nerve. The results confirmed that long-term treatment with KEVEYIS is safe and effective for chronic use. The open label extension results of HYPHOP add to previously reported results from the short-term randomized, double-blind, placebo-controlled phase of the study, with hyperkalemic and hypokalemic PPP sub-studies, which demonstrated the effectiveness of KEVEYIS to prevent attacks of muscle weakness. Adverse event analyses indicated no new safety signals during the final 52 weeks of the study versus the first nine weeks, with the common adverse events of paresthesia and cognition impairment, reported at lower frequencies during the extension as compared with the first 9 weeks. Clinicians can advise patients starting KEVEYIS that most patients who had one of these events initially reported it within the first month of treatment. Temporary dose reduction appeared to be a reasonable approach to manage bothersome paresthesia or cognition-related AEs, as patients with these AEs who were managed with dosage reduction often had subsequent symptom resolution.