FDA Approves Trofinetide for Treatment of Rett Syndrome in Adult, Pediatric Patients

Officials with the FDA have approved trofinetide (Daybue; Acadia Pharmaceuticals Inc) for the treatment of Rett syndrome in adult and pediatric patients 2 years of age and older.

Rett syndrome is a complex, rare, neurodevelopmental disorder typically caused by a genetic mutation on the MECP2 gene. It is characterized by normal development until 6 to 18 months of age, followed by significant developmental regression with loss of acquired communication skills and purposeful hand use.

Symptoms can also include the development of hand stereotypies, such as hand wringing and clapping, as well as gait abnormalities. It is believed to affect 6000 to 9000 patients in the United States, with a diagnosed population of approximately 4500 patients.

“Rett syndrome is a profoundly debilitating and complex, rare, neurodevelopmental disorder that presents differently across patients and can lead to an array of unpredictable symptoms throughout the course of a patient’s life,” said Jeffrey L. Neul, MD, PhD, an investigator on the phase 3 LAVENDER study, in a press release. “Now, for the first time after decades of clinical research, health care providers finally have a treatment option to address a range of core behavioral, communication, and physical symptoms for their patients living with Rett syndrome.”

Trofinetide is a synthetic version of the tripeptide glycine-proline-glutamate (GPE) molecule. The mechanism by which it exerts therapeutic effect in patients with Rett syndrome is unknown, but in animal studies it has been shown to increase the branching of dendrites and synaptic plasticity signals.

The FDA approval is supported by findings from the pivotal phase 3 LAVENDER study evaluating the efficacy and safety of trofinetide versus placebo in 187 female patients with Rett syndrome between 5 and 20 years of age. In the study, treatment with trofinetide demonstrated a statistically significant improvement compared to placebo on both co-primary efficacy endpoints, as measured by the change from baseline in Rett Syndrome Behavior Questionnaire (RSBQ) total score and the Clinical Global Impression-Improvement (CGI-I) scale score at week 12.

The RSBQ is a caregiver assessment that evaluates a range of symptoms of Rett syndrome, including vocalizations, facial expressions, eye gaze, hand movements, repetitive behaviors, breathing, nighttime behaviors, and mood. The CGI-I is a global physician assessment of whether a patient has improved or worsened. The most common adverse effects in the study were diarrhea (82%) and vomiting (29%).

Trofinetide is expected to be available in the United States by the end of April 2023.

“This is a historic day for the Rett syndrome community and a meaningful moment for the patients and caregivers who have eagerly awaited the arrival of an approved treatment for this condition,” said Melissa Kennedy, CEO of the International Rett Syndrome Foundation, in the press release. “Rett syndrome is a complicated, devastating disease that affects not only the individual patient, but whole families. With today’s FDA decision, those impacted by Rett have a promising new treatment option that has demonstrated benefit across a variety of Rett symptoms, including those that impact the daily lives of those living with Rett and their loved ones.”

Acadia Pharmaceuticals is offering an Acadia Connect support program with personal assistance, financial resources, and prescription support for patients receiving trofinetide. Each support team includes a nurse care coordinator, a family access manager, and 24/7 clinical pharmacist support.

REFERENCE

Acadia Pharmaceuticals Announces US FDA Approval of Daybue (trofinetide) for the Treatment of Rett Syndrome in Adult and Pediatric Patients Two Years of Age and Older. News release. BusinessWire; March 10, 2023. Accessed March 13, 2023. https://www.businesswire.com/news/home/20230303005382/en