Efficacy and tolerability of a botulinum toxin type A free of complexing proteins (NT 201) compared with commercially available botulinum toxin type A (BOTOX°) in healthy volunteers

Summary.

Purpose: This randomized controlled trial was performed to compare the novel botulinum toxin type A free of complexing proteins (NT 201) with the marketed preparation BOTOX° regarding efficacy and tolerability. Methods: Fourteen healthy volunteers received a single intramuscular injection into the extensor digitorum brevis (EDB) muscle of either 4 units NT 201, or 4 units of BOTOX° randomised by foot. Compound muscle action potential (CMAP) measurements were recorded for up to 90 days after injection. Results: Both drugs produced a maximum decline between Day 7 and Day 14. At Day 90, administration of both drugs resulted in approximately a 40% CMAP decline as compared to baseline. Duration of paralytic effect was comparable in both groups, at all response thresholds tested. Both drugs were well tolerated. Conclusion: The effects of small amounts of NT 201 and BOTOX° injected into the EDB muscle are comparable in terms of efficacy, time to onset of action, duration of action, and tolerability.