Acadia Pharmaceuticals has received marketing authorisation from Health Canada for DAYBUE (trofinetide) to treat Rett syndrome in adult and paediatric patients aged two years and above.

Rett syndrome is a rare neurodevelopmental disorder that predominantly affects females. It is characterised by a significant regression in development after an initial two years of normal growth. The majority of individuals with Rett syndrome will require lifelong, 24-hour care.

The authorisation, under the priority review process, marks DAYBUE as the first and only drug approved in the country for this purpose.

Acadia CEO Catherine Owen Adams stated: “Health Canada’s authorisation of DAYBUE is a significant milestone for the Rett syndrome community in Canada and another step forward in Acadia’s commitment to increase access to this therapy for patients and their families. We look forward to bringing DAYBUE to Canadian patients with Rett syndrome as soon as possible.”

The approval of DAYBUE in Canada is for use in patients who weigh a minimum of nine kilograms.

It was based on the positive outcomes from the Phase III LAVENDER trial.

The pivotal study assessed the safety and efficacy of trofinetide against a placebo. 187 girls and young women aged between five and 20 participated in the study.

The study’s co-primary endpoints included the change in the total score from baseline in the Rett Syndrome behaviour questionnaire (RSBQ), as reported by caregivers, and the score of clinical global impression-improvement (CGI-I) scale, as evaluated by clinicians, at week 12.

The RSBQ is a 45-item scale filled out by caregivers that evaluates symptoms of Rett syndrome, such as hand movements, repetitive behaviours, night-time behaviours and vocalisations.

In March 2023, the therapy received approval from the US Food and Drug Administration for treating Rett Syndrome.