Risdiplam Meets End Point, Fenfluramine Effective in Treating Dravet Syndrome, Rimegepant Sees Early Results in Migraine

May 2, 2020

Neurology News Network for the week ending May 2.

This week's Neurology News Network was dedicated towards the presentations that were slated for this year's American Academy of Neurology Annual Meeting. We discuss new results on Risdiplam, the responses of those with Dravet Syndrome to fenfluramine, and the data on 3 phase 3 trials of rimegepant.

Marco Meglio: Welcome to this special edition of Neurology News Network. I’m Marco Meglio. Please excuse our appearance this week as a majority of the US workforce, including the NeurologyLive team, moves to working remotely as we come together to help reduce the spread of the novel coronavirus. In this episode, we will take a look at a few of the presentations that were slated for this year’s American Academy of Neurology Annual Meeting.

Genentech announced its investigational, orally administered SMN2 splicing modifier, risdiplam, met the primary end point in the FIREFISH part 2 clinical study by demonstrating a significant increase in achieved motor milestones in infants with Type 1 spinal muscular atrophy aged 1 to 7 months after 12 months of treatment. Using the Gross Motor Scale of the Bayley Scales of Infant and Toddler Development Third Edition, 29% of infants sat without support for 5 seconds by the end of month 12, a milestone typically not reached in the natural history of Type 1 SMA. Additionally, 43.9% of infants were able to hold their head upright, 13 (31.7%) were able to roll to the side, and 4.9% of infants were able to stand with support. The FDA pushed back the regulatory decision of risdiplam but is expected to have an answer in late August.

Real-world data that were accepted for presentation at AAN2020 suggest that those with Dravet syndrome who are treated with fenfluramine have clinically meaningful responses to the therapy, similar to that observed in clinical trials. Scott Perry, lead investigator, and colleagues noted that similar improvements were reported in cognition, behavior, and motor abilities by 56%, 43%, and 48% of the cohort, respectively. At the end of February, the FDA extended the review period for fenfluramine, citing the need for additional time to assess additional data it requested from Zogenix, according to a recent announcement from the company. Its PDUFA action date has been moved to June 25, 2020, a 3-month extension from its original date of March 25.

Results from 3 phase 3 clinical trials of rimegepant demonstrated that the acute migraine treatment was more effective than placebo on efficacy end points measured from 2 hours through 48 hours postdose. Overall, sustained pain relief in that 48-hour window postdose was observed in 37.8% of patients who received rimegepant without rescue medication, compared with 24% of patients on placebo. Researchers noted that the agent numerically separated from placebo on pain relief as early as 15 minutes postdose and was significantly superior to placebo at 60 minutes for pain relief and return to normal function. The therapy was approved by the FDA in February 2020 for the acute treatment of migraine in adults, and became available in pharmacies in early April.

Although AAN has been canceled, the coverage for slated presentations continues. Head to NeurologyLive.com for more direct access to expert insight, as well as the top news from what would have been presented at AAN. This has been Neurology News Network. Thanks for watching.