Use of AbobotulinumtoxinA in Adults with Cervical Dystonia: A Systematic Literature Review

[Impact of botulinum therapy on long-term control of cervical dystonia symptoms and patient satisfaction with treatment: results of the international prospective observational study INTEREST IN CD2 in Russian subgroup of patients]

OBJECTIVE

To evaluate effect of long-term BTA treatment on cervical dystonia (CD) symptoms control and patient satisfaction with botulinum therapy in real life setting.

MATERIAL AND METHODS

A total of 1050 patients took part in the international observational study INTEREST IN CD2, the analysis included data from 995 patients (overall population), of which 56 patients were enrolled In Russia. CD clinical assessment was performed at baseline and on the days of BTA injections using the TWSTRS scale and tremor component of the Tsui scale. Patient satisfaction with CD symptoms control was evaluated using 5-point Likert scale on the day of the visit (today satisfaction) and the highest level of satisfaction at any time since the last BTA injection (highest satisfaction). This article presents the results of the analysis of the Russian subgroup of patients in comparison with the overall study population.

RESULTS

In 5 Russian investigational sites, 44 (78.6%) women and 12 (21.4%) men were enrolled in the study; the patients' mean age was 51.1±9.6 years, the mean duration of the disease was 7.3±5.6 years. The baseline characteristics of the Russian patients were comparable to the overall population, but severity of CD symptoms was numerically higher in the Russian subgroup: the mean TWSTRS severity scores were 17.4±5.0 and 15.9±5.7, respectively; segmental dystonia was observed more frequently (14.3% and 7.4% of patients), as well as shoulder elevation (73.2% and 50.5%) and jerk (21.4% and 9.6%). The vast majority of Russian patients (82.1%) received treatment with abobotulinumtoxin (Dysport). In the Russian subgroup, higher doses of Dysport (median doses 800.0 U and 500.0 U), larger number of targeted muscles (4.3±1.5 and 3.5±1.5) and injection points (11.7±5.5 and 8.1±5.0) were used compared to the overall population. In the Russian subgroup, the mean TWSTRS total score (assessed at the end of each injection cycle) decreased from 32.3±11.2 to 25.2±15.7 over the 3 years follow-up; there was also decrease in severity score from 17.4±5.0 to 12.6±7.5 and disability score from 9.8±4.0 to 7.4±4.8, comparable to the overall population. Patients' satisfaction with CD symptoms control at peak of the BTA injection effect increased from 92.5% to 98.1% and was higher than in the overall population. At the end of the treatment cycle, patients' satisfaction was consistently lower than at peak effect.

CONCLUSION

The results of the Russian subgroup analysis showed a high level of long-term effectiveness of botulinum therapy in controlling CD symptoms and patients' satisfaction with treatment in real clinical practice. Dysport is the most frequently used BTA preparation In Russia, the optimal level of effectiveness with repeated injections of Dysport remains stable and is maintained within the framework of real-life practice, which supports the clinical guidelines recommendations of its use as the drug of choice in the treatment of patients with CD.

Editorial on the Special Issue "Botulinum Toxin for the Treatment of Neurological Disorders: Where We Are and Where We Need to Go"

Over the past 30 years, botulinum toxin (BoNT) has seen an ever-expanding use in disorders afflicting the nervous system [...].

Factors Influencing the Surgical Decision in Dystonia Patients Referred for Deep Brain Stimulation

There is no available data on the journey of dystonia patients once referred to a tertiary center to undergo deep brain stimulation (DBS). We hypothesized that some patients might be incorrectly diagnosed while others might decline the procedure or experience significant benefit with switching to a different botulinum neurotoxin (BoNT). This is a single-center, retrospective study of dystonia patients who were referred to the DBS program between January 2014 and December 2018. We collected data on the surgical decision as well as factors influencing this decision. Sixty-seven patients were included (30 males, mean age: 48.3 ± 20.1 years, disease duration: 16.9 ± 15.3 years). Thirty-three (49%) patients underwent DBS. Four (6%) patients were awaiting the procedure while the remaining 30 patients (45%) did not undergo DBS. Reasons for DBS decline were patient refusal (17, 53%), functional dystonia (6, 20%), and successful use of AbobotulinumtoxinA (3, 10%) in patients who had failed other BoNTs. Our study highlights the importance of structured patient education to increase acceptance of DBS, as well as careful patient evaluation, particularly with respect to functional dystonia. Finally, changing BoNT formulation might be beneficial in some patients.

Long-term efficacy and safety of botulinum toxin treatment for cervical dystonia: a critical reappraisal

Introduction: Botulinum toxin (BoNT) injections represent the gold standard treatment for cervical dystonia (CD). Different types of BoNT have been used for the treatment of CD, but only two serotypes, BoNT type A (BoNT-A) and type B (BoNT-B), have been approved by regulatory agencies. Efficacy and safety of BoNT have been well documented by many short-term studies, but the longterm effects have been investigated only relatively recently.Areas covered: In the present review, we aimed to critically reappraise the existing evidence on the long-term efficacy and safety of BoNT treatment in CD. The examined studies mainly explored BoNT-A serotypes. Only a few studies examined the long-term effects of BoNT-B serotypes, and only one head-to-head comparison between BoNT-A and BoNT-B was found. BoNT was consistently reported to be an effective and safe treatment for CD patients, with good outcomes and a few adverse events in the long-term. However about a third of patients still drop out from the treatment during a long-term follow-up.Expert opinion: We conclude that BoNT is safe and effective in the long-term treatment of patients with CD. Additional studies are needed to further explore patients real-life experiences and perspectives to better understand the long-term outcomes and reasons for discontinuation of treatment.