Dysport and Botox at a ratio of 2.5:1 units in cervical dystonia: A double‐blind, randomized study

Abstract

We aimed to compare Dysport (abobotulinumtoxinA, Ipsen Biopharm, Slough, UK) and Botox (onabotulinumtoxinA, Allergan, Irvine, CA, USA) at a 2.5:1 ratio in the treatment of cervical dystonia (CD). A Dysport/Botox ratio of lower than 3:1 was suggested as a more appropriate conversion ratio, considering its higher efficacy and more frequent incidence of adverse effects not only in the treatment of CD but also in other focal movement disorders. A randomized, double-blind, multicenter, non-inferiority, two-period crossover study was done in CD, with a duration of at least 18 months. Patients were randomly assigned to treatment for the first period with Dysport or Botox, and they were followed up for 16 weeks after the injection. After a 4-week washout period, they were switched to the other formulation and then followed up for 16 weeks. The primary outcome was the changes in the Tsui scale between the baseline value and that at 1 month after each injection. A total of 103 patients were enrolled, and 94 completed the study. Mean changes in the Tsui scale between baseline and 4 weeks after each injection tended to favor Botox; however, this was not statistically significant (4.0 ± 3.9 points for the Dysport treatment vs. 4.8 ± 4.1 points for Botox; 95% confidence interval, −0.1-1.7; P = 0.091). The mean change of the Toronto western spasmodic torticollis rating scale score, the proportion of improvement in clinical global impression and patient global impression, and the incidences of adverse events were not significantly different between the two treatments. With regard to safety and efficacy, Dysport was not inferior to Botox in patients with CD at a conversion factor of 2.5:1. [http//clinicaltrial.gov: NCT00950664] © The Authors. Movement Disorders published by Wiley Periodicals, Inc. on behalf of International Parkinson and Movement Disorder Society.

Practice guideline update summary: Botulinum neurotoxin for the treatment of blepharospasm, cervical dystonia, adult spasticity, and headache

“…In a Class II 9-month randomized, double-blind, multicenter, noninferiority, 2-period crossover study with a 2.5:1 (aboBoNT-A:onaBoNT-A) protocol involving 103 patients with CD, 94 of whom completed the study, there were no statistically significant differences between aboBoNT-A and onaBoNT-A in mean changes in the Tsui scale (0.8 points favoring onaBoNT-A, 95% CI 20.1 to 1.7), TWSTRS, global impression, or frequency of AEs from baseline to 4 weeks after each injection. 24 In another comparison study (Class II), 46 patients with CD were enrolled in a double-blind, randomized, crossover trial of onaBoNT-A vs aboBoNT-A in 1:3 dose conversion ratios. There was no significant difference between the 2 products at week 4, but at week 12 there was a significantly shorter duration and lower efficacy of onaBoNT-A assessed by reduction in TWSTRS total score, suggesting that the optimal conversion ratio between onaBoNT-A and aboBoNT-A is lower than 1:3.…”

Pharmacological differences and clinical implications of various botulinum toxin preparations: a critical appraisal

“…A more recent study that used DAbS to compare the ED 50 of different BoNTAs showed that a DAbS of 2 could be obtained with 6 U of onabotulinumtoxinA and 10 U of incobotulinumtoxinA (Brown et al, 2013). Overall, onabotulinumtoxinA showed greater efficacy and longer effect duration than incobotulinumtoxinA at both high and low dosages in the DAbS model (Brown et al, 2013 (Marion et al, 1995) 1: 3 NA (Nussgens and Roggenkamper, 1997;Roggenkamper et al, 2006) 1: 4 AbobA>OnabA (Sampaio et al, 1997) 1: 4 AbobA>OnabA (Bihari, 2005) 1: 4 -1: 5 NA (Bentivoglio et al, 2012) 1: 1 -1: 13.3 NA (Dodel et al, 1997) 1:4 -1:6 AbobA>OnabA Cervical dystonia (Naumann et al, 2003) 1: 5 -1: 6 AbobA=OnabA (Odergren et al, 1998) 1: 3 AbobA=OnabA (Ranoux et al, 2002) 1: 3 -1: 4 AbobA>OnabA (Bihari, 2005) 1: 4 -1: 5 NA (Misra et al, 2012) 3.1: 1 AbobA>OnabA (Rystedt et al 2015) 1.7: 1 NA (Yun et al 2015) 2.5: 1 AbobA=OnabA (Dodel et al, 1997) 1:4 -1:6 AbobA>OnabA (Van den Bergh and Lison, 1998) 1: 2.5 AbobA=OnabA Hemifacial spasm (Marion et al, 1995) 1: 3 NA (Bihari, 2005) 1: 4 -1: 5 NA (Dodel et al, 1997) 1:4 -1:6 AbobA>OnabA (Van den Bergh and Lison, 1998) 1: 2.5 AbobA=OnabA Spasticity (Rasmussen, 2000) 1: 4 NA (Bhakta et al, 1996) 1: 4 -1: 5 NA (Hesse et al, 2012) 1: 5 NA ( Keren-Capelovitch, et al 2010) 1: 2.5 NA Abbreviations: OnabA =OnabotulinumtoxinA; AbobA=AbobotulinumtoxinA; NA=not available/not applicable © C I C E d i z i o n i I n t e r n a z i o n a l i at least 12 months, were administered increasing doses of onabotulinumtoxinA until a similar response to that obtained with abobotulinumtoxinA was observed. The dose ratio between onabotulinumtoxinA and abobotulinumtoxinA was 1:3 (Marion et al, 1995).…”

Practical Tips on Botulinum Toxin Injections

“…However, in real practice, patients who have been treated with diferent "oNT products could visit your clinic any time. In this regard, a simple conversion ratio between "otox ® and Dysport ® was made [11]. "ased on the average recommended dose of Dysport ® 500 Units and "otox ® 200 Units for patients with cervical dystonia, a conversion ratio of 2.5:1 was assumed and it was found that Dysport ® showed no inferiority to "otox ® at this ratio.…”

“…However, the biological activity varies between "oNTs. "lthough there is no consensus for the conversion ratio, we use the ratio of 2.5:1 for Dysport ® and "otox ® because the non-inferiority of Dysport ® has already been proven [11]. On the assumption that the ratio of 2.5:1 is bioequivalent, the practitioner can make two kinds of solutions Table . To make a solution with a high concentration, 1 ml of 0.9% normal saline is needed for 1 ample 100 Units of "otox ® and 2 ml of 0.9% normal saline for 1 ample 500 Units of Dysport ® .…”