Treatment-Naïve Patients

The efficacy and safety of XEOMIN for the treatment of blepharospasm in treatment-naïve patients were evaluated in Study 1 (NCT01896895), a randomized, double-blind, placebo-controlled, multi-center trial in a total of 61 patients. Patients had a clinical diagnosis of blepharospasm, with a baseline Jankovic Rating Scale (JRS) severity subscore ≥2. Patients were defined as treatment-naïve if at least 12 months had passed since their last botulinum toxin treatment for blepharospasm. During the placebo-controlled phase, a fixed total dose of 25 Units XEOMIN (n=22), 50 Units XEOMIN (n=19), or placebo (n=20) was administered intramuscularly at 6 injection sites per eye (Figure 9). Of the 61 patients randomized, 55 patients completed the placebo-controlled phase. Patients only continued to the open-label extension (OLEX) period if they had a confirmed need for a re-injection by week 20 of the placebo-controlled phase. A total of 39 patients entered and completed the OLEX phase.

The primary efficacy variable was the change from baseline in JRS Severity subscore determined at Week 6 after the injection. The 50 Unit treatment group demonstrated statistically significant improvements compared to placebo, with a difference of -1.2 (p=0.0004). The change from baseline in the JRS Severity subscore for the 25 Unit treatment group 6 weeks after the injection was not statistically significant, with a difference of -0.5 (p=0.1452) compared to placebo (see Figure 9).

Figure 9: Frequency Distribution of Changes from Baseline JRS Severity Subscore at Week 6 for Treatment-Naïve Patients

Pre-Treated Patients

The efficacy and safety of XEOMIN for the treatment of blepharospasm patients pre-treated with onabotulinumtoxinA (Botox) were evaluated in Study 2 (NCT00406367), a randomized, double-blind, placebo-controlled, multi-center trial in a total of 109 patients. Patients had a clinical diagnosis of benign essential blepharospasm, with baseline JRS Severity subscore ≥2, and a stable satisfactory therapeutic response to previous administrations of onabotulinumtoxinA (Botox). At least 10 weeks had to have elapsed since the most recent onabotulinumtoxinA administration. Patients with any significant neuromuscular disease that might interfere with the study were excluded from enrollment. Patients were randomized (2:1) to receive a single administration of XEOMIN (n=75) or placebo (n=34). Each patient in the XEOMIN group received a XEOMIN treatment (dose, volume, dilution, and injection sites per muscle) that was similar to the most recent onabotulinumtoxinA injection sessions prior to study entry. The highest dose permitted in this study was 100 Units (50 Units per eye); the mean XEOMIN dose was 33 Units per eye.

In Table 24 the most frequently injected sites, the median dose per injection site, and the median number (and range) of injection sites per eye are presented.

Patients were assessed during clinic visits at Weeks 3 and 6, and then by telephone or at clinic visits every two weeks up to Week 20.

The mean age of the study patients was 62 years, 65% of the patients were women, and 83% were White. The study was completed by 94% of study patients. Approximately one third of patients had other dystonic phenomena; in all but 1% this was limited to facial, cervical, perioral and mandibular muscles. No patients discontinued the study prematurely due to adverse events.

The primary efficacy endpoint was the change in the JRS Severity subscore from baseline to Week 6 post-injection, in the intent-to-treat (ITT) population, with missing values replaced by the patient's most recent value (i.e., last observation carried forward). In the ITT population, the difference between the XEOMIN group and the placebo group in the change of the JRS Severity subscore from baseline to Week 6 was -1.0 (95% CI -1.4; -0.5) points. Comparison of the XEOMIN group to the placebo group was statistically significant at p<0.001.

Figure 10: Frequency Distribution of Changes from Baseline JRS Severity Subscore at Week 6

Examination of age and gender subgroups did not identify substantial differences in response to XEOMIN among these subgroups.