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Pillar 4 presentation: the Observer-Reported Communication Ability Measure

This week we are going to continue highlighting research that falls under Pillar 4 - Accelerating and Preparing for Clinical Trials in our Roadmap to a Cure 2.0. We will feature Dr. Christina Zigler’s update from the 2022 FAST Science Summit on the Observer-Reported Communication Ability Measure (ORCA) and how it helps to capture communication abilities in individuals living with AS.

Communication is uniquely challenging to measure in individuals living with Angelman syndrome as most are profoundly impacted in their expressive communication abilities, while having stronger receptive and pragmatic communication abilities. This results in lower scores on the existing standard assessments that do not account for their dyspraxia and apraxia, making it very hard to test individuals living with AS in a clinical setting. Because of these challenges scores on standard neuropsychological assessments in communication often fall in the lower range of the spectrum, making it very difficult to measure change over time; those living with AS are often times not quite registering on these assessments. This is called a floor effect, which makes it difficult to distinguish between an individual’s real scores and to measure improvements that could be largely meaningful to the individual but not quite captured on the assessment. As clinical trials for Angelman syndrome are advancing there is a clear need for a meaningful and measurable communication tool, knowing that improvements in communication abilities is the leading symptom domain of desired change by most caregivers and loved ones that live with AS. After feedback from the FDA, FAST has been working with the research team at Duke University, led by Drs. Christina Zigler and Bryce Reeve, to develop a communication tool specific to Angelman syndrome. This tool is meant to be used in clinical trials. The tool is designed to carefully measure receptive, expressive, and pragmatic communication abilities in all individuals with Angelman syndrome, and is currently being utilized in all active clinical trials for Angelman syndrome. This tool is called the Observer-Reported Communication Ability Measure (ORCA).

The ORCA was developed with input from approximately 300 AS families and is inclusive of all modalities of communication including words, gestures, and assistive technology. The ORCA is a caregiver-reported assessment, is available in 16 different languages, and can be used for any individual living with AS, regardless of genotype. Importantly, in a sample of 249 AS individuals that were assessed with this tool, the mean score fit in the middle of a bell curve, meaning there was no floor effect for communication. This is exciting because this supports this measure may be able to capture improvements in a more sensitive way for those living with Angelman syndrome. This tool is now being developed for 15 other neurodevelopmental disorders through an FDA-sponsored grant.

For more information, watch the whole talk here: