Improvement in symptoms of Rett syndrome with trofinetide beyond clinical trial efficacy assessments: case reports

Trofinetide is the first approved treatment for Rett syndrome (RTT) in adults and pediatric patients aged ≥2 years. In LAVENDER and DAFFODIL, clinical studies of trofinetide in female participants with RTT, the efficacy of trofinetide was evaluated with the caregiver- and clinician-assessed questionnaires that measure RTT symptom improvement. These scales do not measure improvements in all symptoms of RTT. Here, we present three female patients with RTT treated with trofinetide that aim to describe improvements in symptoms of RTT not properly covered by clinical study efficacy end points. The first case is focused on improvements in verbal communication skills, the second case is focused on reduction in the incidence of seizures with improvement in sleep, and the third case focuses on improvements in motor skills. These anecdotal, real-world cases suggest that trofinetide could improve symptoms of RTT not covered in clinical trial outcomes.