In 2013, the Morells welcomed two identical baby girls, Kaylie and Kenzie.
The joy they felt soon disappeared as the twins began to slip back from their normal infant and toddler milestones. Kassie Morell told BioSpace that when Kenzie was around 15 months old, she started to regress, with Kaylie following a year and a half later, losing her ability to walk and speak. Then in 2016, both of Kassie’s little girls were diagnosed with Rett syndrome, a rare neurodevelopmental disorder. The symptoms are severe loss of hand function, impaired gait, and loss of language.
Watching Their Twins Regress
Both of the girls’ regressions involved screaming, grinding their teeth and hand wringing, and inability to use their hands. The girls seemed to be in a fog and were not interested in events happening around them. Although Kenzie and Kaylie received the same diagnosis and have the same mutation, Rett syndrome has affected them differently. Kaylie was able to walk and speak but she eventually lost her ability to form words. While Kenzie developed more severe symptoms and was never able to crawl or walk and requires the full-time use of a wheelchair. Kenzie is also unable to use her hands, has seizures, and uses a feeding tube.
Hoping for a Cure
At first, the doctors were unable to give the parents any good news and explained that no treatments exist that are tailored to Rett. They told the Morells that the best they could do was manage the symptoms.
Then in March 2021, their hopes were lifted when the girls enrolled in a Phase III clinical trial investigating Daybue (Trofinetide) developed by Neuren Pharmaceuticals and Acadia Pharmaceuticals. Within twelve weeks, the girls were given their first dose of the drug. The trial is an open-label trial meaning that all participants know what drug they will receive.
Some Welcomed Improvements
The improvements since the girls started the drug have given their parents ‘lots of hope’. They point out that the twins are more responsive and focused with better control of facial expressions. According to their mother Kassie, they are happier and have more energy.
The girls have both regained some use of their hands and can turn pages of their books when reading together. Although neither girl is able to speak at this point, they have their methods of vocalization.
About Trofinetide
The drug Trofinetide is a synthetic form of a naturally occurring molecule called tripeptide glycine-proline glutamate. Although the researchers have not completely analyzed the drug’s mechanism, Trofinetide has demonstrated neuroprotective elements in laboratory animals and improved brain function.
Effects of Rett Syndrome
Kathie Bishop, head of rare diseases at Acadia, explains that in cases of Rett syndrome, the connection among brain cells is lost, and the neurons cannot communicate. Kathie told BioSpace that Daybue regenerates these connections.
Kassie said that it is such a relief, and they are so grateful that there is even one drug available to target Rett syndrome.
The twins enjoy walks, museums and, as they love to read, they enjoy visiting the library. Kassie says that they love to be with people, have someone read to them, and enjoy special TV shows.
A few weeks ago, the twins attended a gala dedicated to Rett syndrome patients. It was a thrill to be wearing jewelry and being ‘dressed up’. Their older brother, Jackson, came home from college for Thanksgiving and enjoyed being with his sisters.
Daybue is still in its early stages. No one knows how it will perform now or in the future. But Kassie is pleased with the twin’s progress and sees improvement every day.
