KEVEYIS for PPP: long-term data from the 1-year, open-label extension study1
Study design1:
From the 9-week, double-blind phase of Study 1, 41 of 44 patients in the hypokalemic substudy (KEVEYIS, n=22) and 17 of 21 patients in the hyperkalemic substudy (KEVEYIS, n=9) moved into a 1-year, open-label extension (OLE) phase in which all participants received KEVEYIS.
Average attack rate per week for patients on KEVEYIS at weeks 54-611*


AR=attack rate; IQR=interquartile range; Wk=week.
- *During the 1-year, uncontrolled extension phase, outcomes assessed included attack rate, severity-weighted attack rate, total attack duration per week (from weeks 54-61), and changes from week 9 to 61 in measures of strength and lean body mass. Adverse events and other safety outcomes were also considered.
- †Of the 17 patients who were enrolled in the long-term extension of the hyperkalemic PP trial, data were excluded for 1 patient in the 52-week, uncontrolled extension phase, who was included in the 9-week phase, as this participant was randomized to acetazolamide (the acetazolamide arm of the trial had to be abandoned owing to poor recruitment).
Characterization of common adverse events in the double-blind and OLE studies
An ad hoc analysis was performed to characterize the time course, intensity, and outcomes of paresthesia and cognition-related AEs during 61 weeks of KEVEYIS treatment for PPP
Cognition-related AEs included cognitive disorder, disturbance in attention, and mental impairment during 61 weeks of treatment in Study 1.2
Paresthesia and cognition-related AEs—the onset typically occurred during the first 4 weeks of treatment with KEVEYIS2
- 25 of 63 (39.7%) patients had ≥1 report of paresthesia, and 16 of 63 (25.4%) patients had ≥1 cognition-related event
- All reports of paresthesia were considered mild or moderate in intensity
- The majority (88%) of cognition-related events were mild to moderate in intensity
Reductions in dose were commonly associated with resolution of AEs2
- 6 of 25 (24.0%) patients with paresthesia had a reduction in the dose of KEVEYIS, and paresthesia resolved in 5 of the 6 cases
- 6 of 16 (37.5%) patients with cognition-related AEs had a reduction in the dose of KEVEYIS, and the cognition-related AE resolved in all 6 cases
AEs were not frequently associated with discontinuation from the study2
- Of the 63 patients, 1 patient discontinued due to paresthesia and 4 patients discontinued due to cognition-related AEs