Switchover study of onabotulinumtoxinA to incobotulinumtoxinA for facial dystonia

Patient-reported outcomes following a break in ophthalmic botulinum toxin therapy during the COVID-19 pandemic

OBJECTIVE

To evaluate the effect of a break in botulinum toxin treatment, necessitated by the COVID-19 pandemic, on patients' quality of life.

METHODS

Prospective cohort study of all patients undergoing incobotulinumtoxinA treatment in our department-for benign essential blepharospasm (BEB), hemifacial spasm (HFS), aberrant facial regeneration (AFR), or crocodile tears-who were affected by the break in service (March 18, 2020-June 17, 2020). All patients who received treatment both before and after the break in service were included. Data gathered included subjective patient-reported measure of "time until treatment failure" and disease rating scale scores: Blepharospasm-Dystonia Functional Disability Assessment Scale (BDFDAS; for BEB, HFS, and AFR); Jankovic Rating Scale (JRS; for BEB and HFS); and TEARS Epiphora Grading Scale (for crocodile tears).

RESULTS

Across 72 patients, there was a mean treatment delay of 3.9 months (range, 0-9.8 months). After a period of effect, treatment failed in all patients, with a mean time until treatment failure of 3.9 months (range, 0.5-12.0 months). All patient-reported outcome measurements increased, with greatest effect seen in AFR (178% increase in BDFDAS) and BEB (41% increase in JRS). At least 2 patients sought and underwent retreatment elsewhere in the private sector because of their symptom severity.

CONCLUSIONS

Patients with AFR and BEB are likely to tolerate a break in service least, whereas patients with crocodile tears appear to be less affected. This real-world snapshot allows quantification of the harm caused by a break in botulinum toxin service or a treatment delay. This study provides valuable information should further breaks in service or treatment delay be considered in the future due to a further wave of COVID-19 or other reasons.

Botulinum Toxin for the Treatment of Hemifacial Spasm: An Update on Clinical Studies

Hemifacial spasm (HFS) is a movement disorder characterized by involuntary contractions of the facial muscles innervated by the seventh cranial nerve. Generally, it is associated with a poor quality of life due to social embarrassment and can lead to functional blindness. Moreover, it is a chronic condition, and spontaneous recovery is rare. Intramuscular injections of Botulinum Toxin (BoNT) are routinely used as HFS treatment.

METHODS

We reviewed published articles between 1991 and 2021 regarding the effectiveness and safety of BoNT in HFS as well as any reported differences among BoNT formulations.

RESULTS

The efficacy of BoNT for HFS treatment ranged from 73% to 98.4%. The mean duration of the effect was around 12 weeks. Effectiveness did not decrease over time. Adverse effects were usually mild and transient. The efficacy and tolerability of the different preparations appeared to be similar. Among the studies, dosage, injected muscles, intervals of treatment, and rating scales were variable, thus leading to challenges in comparing the results.

CONCLUSIONS

BoNT was the treatment of choice for HFS due to its efficacy and safety profile. Further studies are needed to investigate the factors that influence the outcome, including the optimal timing of treatment, injection techniques, dosage, and the best selection criteria for formulations.