Background Each botulinum toxin type A product is a unique biological. Due to differences in physicochemical characteristics, measurement of unit doses and dosing regimens they cannot be considered as biosimilars.

Purpose To assess the relative doses used in clinical practise of two different brands of botulinum toxin type A, Dysport and Botox, in focal dystonias (FD), hemifacial spasm (HS) and juvenile cerebral palsy (JCP).

Materials and Methods A systematic review of studies conducted in a variety of countries. The comparison of Dysport with Botox was carried out in accordance with guidelines from the Cochrane collaboration and AHTAPol (Agency for Health Technology Assessment in Poland). Search terms included botulinum toxin type A, dystonic disorders, blepharospasm, hemifacial spasm and cerebral palsy. Concurrently an electronic survey was conducted of eleven Polish doctors, which captured data from 101 of their patients.

Results The systematic review of studies of treating FD and HS with botulinum toxin type A found that where 1.00 unit of Botox is used to treat a patient, between 2.56 and 5.00 units of Dysport are used to treat a patient diagnosed with the same condition. No clinical trials comparing Dysport to Botox were found for JCP. Mean age and percentage of female patients included in the survey was 58.3, 54.7 and 8.9 years; 59.5%, 45% and 40.7% for FD, HS and JCP respectively. Based on information from patient data collected and surveyed doctors’ estimates, the doses for Dysport reflected a broad range within and across indications and were on average 4.18–4.78 times those for Botox in FD and HS and 2.41–3.18 times those for Botox in JCP (overall range 2.41–4.78).

Conclusions Botox and Dysport are not interchangeable. The doses used in Poland are consistent with the results of the REAL DOSE study [1]. Treatment is individualised according to patient needs, experience and doctors’ preferences.

Reference

1. Marchetti A et al, Retrospective evaluation of the dose of Dysport and Botox in the clinical management of cervical dystonia or blepharospasm (The REAL DOSE Study), Movement Disorders Vol. 20, No. 8, 2005, pp. 937–944

No conflict of interest.