Dysport Therapeutic has been approved by Health Canada for the treatment of spasticity affecting the lower limbs in adults, which could be of enormous benefit for patients with conditions such as cerebral palsy.
Spasticity is a condition in which certain muscles are permanently contracted as a result of damage to nerve pathways from the brain or spinal cord. It is seen in many different conditions such as cerebral palsy, traumatic brain injury, spinal cord injury, stroke and multiple sclerosis.
Dysport Therapeutic (AbobotulinumtoxinA) is an injectable form of a chemical (botulinum toxin type A, or BoNT-A) that is isolated from a bacterium known as Chlostridium. It is injected directly into affected muscles and works by blocking nerve signals that cause abnormal muscle contraction and tightness.
The approval comes after a Phase 3 clinical trial (NCT01249404), which tested the effectiveness of Dysport Therapeutic compared to placebo in improving muscle tone. The study included 385 patients with lower limb spasticity and concluded that Dysport injection resulted in a statistically significant improvement in muscle tone and spasticity at the ankle joint after four weeks of treatment.
The duration of response for the majority of patients within the study was between 12-16 weeks, with some patients experiencing a longer response period. This was succeeded by a follow-on Phase 3 study (NCT01251367), which involved 352 patients and demonstrated that Dysport Therapeutic was effective and well-tolerated for the treatment of patients with lower limb spasticity. Adverse reactions observed in patients who received the drug included falls, as well as muscular weakness and pain.
Theodore Wein, MD, assistant professor of neurology and neurosurgery, Stroke Prevention Clinic, Montreal General Hospital, Montreal, Quebec, said that “in addition to rehabilitation, botulinum neurotoxin medication represents an important intervention in helping patients impacted by lower limb spasticity move towards improving their function and ultimately their quality-of-life.” He added, “Now that Dysport Therapeutic is approved for the treatment of patients with spasticity in the upper or lower limbs, it represents a valuable treatment option to help them improve their lives.”
Janice Bushfield, executive director, Cerebral Palsy Association in Alberta, Calgary, Alberta, also welcomed the approval and said “recognizing that lower limb spasticity can be very debilitating for individuals with cerebral palsy, treatment interventions like Dysport Therapeutic are very beneficial as they can help adult patients live with the least amount of restriction and improve mobility.”
Dysport already is approved in the U.S. as a therapy for lower limb spasticity in adults.