Pitolisant as a Treatment for Prader-Willi Syndrome
Las Vegas, NV – The 2018 Foundation for Prader-Willi Research (FPWR) annual research symposium included a presentation and a poster suggesting that pitolisant may be a safe and effective treatment for Prader-Willi Syndrome (PWS). Marta Pace, PhD, post-doctoral fellow at the Instituto Italiano di Tecnologia in Italy gave the talk, “Histamine-3 inverse Agonist Pitolisant: May it Constitute a New Therapeutic Approach for Prader-Willi Syndrome?” Her talk was followed in the evening with the poster by Lara C. Pullen, PhD, president of the Chion Foundation in Chicago, Illinois, and colleagues entitled, “Cognitive Improvements in Children with Prader-Willi Syndrome Following Pitolisant Treatment.” Their poster presented patient-reported experiences suggesting that pitolisant may represent a novel therapeutic option to relieve substantial PWS disease burden including cognitive disability, excessive daytime sleepiness, and poor-quality nighttime sleep. The data were systematically collected from families via an online system named TREND Community (https://trend.community/).
The poster by Pullen and colleagues presented dosing data from nine children in the United States with PWS who continue to be treated with pitolisant. Parents obtained a prescription for pitolisant from their personal physicians, purchased the medication from Germany, and imported it to the United States via personal importation allowed at the Federal Drug Administration’s discretion. The families agreed to systematically document their experiences online on the TREND Community platform (https://trend.community/) to benefit the larger PWS community.
The authors noted that while nine children continue on pitolisant, one discontinued due to anxiety and behavioral issues. The data suggest that children with PWS appear to benefit from dosing that is higher than the 18 mg currently being tested in children with narcolepsy. Specifically, the two children younger < 6 years of age were dosed as high as 31.5 mg/daily, the five children aged 6-12 years were dosed as high as 27 mg daily, and the two children > 12 years were dosed as high as 36 mg. In all cases, the dosing regimen was gradually increased until the effective dose for each child was reached. The investigators detailed data from three children with PWS who were treated with pitolisant and reported that these children experienced improved mental clarity and processing speed. The authors concluded that pitolisant may be able to improve cognition in children with PWS.
Pitolisant has been approved in Europe for the treatment of adults with narcolepsy and/or cataplexy. The researchers note that excessive daytime sleepiness affects more than half of individuals with PWS. They go on to suggest that many individuals with PWS would likely qualify for a diagnosis of narcolepsy. They also noted that the three children in their case series, while frequently sleepy during the day and presenting with global low tone, did not present with typical adult symptoms of narcolepsy. The investigators thus concluded that individuals with PWS (with and without a diagnosis of narcolepsy) may benefit from treatment with pitolisant.
