The severity of primary axillary hyperhidrosis (PAH) decreased in more than half of patients who received onabotulinumtoxinA injections, in a nonrandomized, open-label study.
The researchers gave 144 adolescents with PAH up to six treatments with the drug, with retreatment occurring no sooner than 8 weeks after a prior treatment and no later than 44 weeks after the initial treatment.
Patients were retreated if they had 50 mg or more of spontaneous resting axillary sweat production in each axilla, following injections to each axilla. Fifty-six patients received one treatment, 59 patients received two treatments, 20 received three treatments, 6 received four treatments, and 3 received five treatments. Patients’ scores on the 4-point Hyperhidrosis Disease Severity Scale (HDSS) were among the measures used to evaluate responses to the onabotulinumtoxinA injections.
Results showed that 72.3% of patients experienced at least a 2-point improvement in their HDSS score at 4 weeks after their first treatment, and 56.6% of patients experienced a 2-point or greater improvement at 8 weeks following their second round of injections.
Mean sweat production declined by an average of 83.9% 4 weeks after treatment, and by an average of 78.1% 8 weeks after treatment. More than 50% of patients experienced at least a 90% reduction in sweat production at the 4th week following one of their injections (either the first, second, or third treatment).
Ninety-two patients (63.9%) reported experiencing adverse events (AEs), with upper respiratory tract infections having occurred the most frequently. While most of such adverse events “were mild or moderate in severity,” three patients experienced serious AEs and an additional three experienced severe AEs. Eight patients (5.6%) had 10 treatment-related AEs, including hyperhidrosis (back and palms), injection-site pain, lymphadenopathy, nausea, injection-site irritation, self-reported compensatory sweating (palms), dizziness, and pruritus.
“This study demonstrated that the efficacy and safety of onabotulinumtoxinA in treating PAH reported in previous registration clinical trials in adults can be extended to adolescents,” wrote Dr. Dee Anna Glaser of Saint Louis University and her colleagues.
Dr. Glaser is a paid consultant and investigator for Allergan, Dermira, and Miramar Labs. She has received research grants and honoraria from these companies and is an investigator for Ulthera. Her coauthors disclosed ties to Allergan.
Read the study in Pediatric Dermatology (doi: 10.1111/pde.12620).