Ipsen announces late-breaking data from first head-to-head study comparing Dysport® and Botox® in adults with upper limb spasticity

Ipsen announced results from the DIRECTION trial, a Phase IV, randomized, double-blind study comparing Dysport® (abobotulinumtoxinA) and Botox® (onabotulinumtoxinA) in adults with upper limb spasticity (ULS). The trial met its primary and secondary endpoints, showing Dysport’s safety profile was non-inferior to Botox, with a treatment-emergent adverse event rate of 20.3% versus 23.0%. Patients treated with Dysport also experienced a longer duration of effect (14.2 weeks) compared to Botox (13.8 weeks), with statistical significance favoring Dysport in pre-specified analyses. The DIRECTION trial involved 464 participants across 72 sites in the USA, France, and Canada, with an average age of 57 and two-thirds male. Most patients had spasticity due to stroke. The study used a crossover design, with each participant receiving one treatment cycle of each toxin via standardized, instrument-guided techniques. These results address a decades-long evidence gap by providing the first direct comparison between Dysport and Botox in ULS. Ipsen highlighted the importance of treatment durability, as over 80% of patients experience breakthrough symptoms between injection cycles. The data will be presented as a late-breaking session at the International Society of Physical and Rehabilitation Medicine (ISPRM) congress in Vancouver on May 19, 2026. Principal investigator Dr. Alberto Esquenazi stated the findings offer meaningful data for clinicians, distinguishing the performance of the two widely used botulinum toxin treatments. Ipsen’s Chief Medical Officer, Sandra Silvestri, emphasized the trial’s role in supporting real-world practice, noting that longer-lasting symptom control improves patients’ function, mobility, and quality of life. The trial’s secondary efficacy endpoint confirmed Dysport’s longer duration of effect across most demographic and clinical subgroups. This aligns with published research indicating that over 70% of patients with ULS require longer-lasting treatments. The results reinforce Dysport’s established safety profile while demonstrating its potential advantages in managing spasticity symptoms.