Qualitative Assessment of the Idiopathic Hypersomnia Severity Scale: Suitability for Use As a Clinical Trial Endpoint as Demonstrated in NCT05156047
Author(s)
Elizabeth Merikle, PhD1, Salvatore Insana, PhD2, Kelly Johnston, MPH1, Michelle Manuel, BS2, Katie Wilmsen, BS2, George Nomikos, MD, PhD2;
1Fortrea Inc., Durham, NC, USA, 2Harmony Biosciences Management Inc., Plymouth Meeting, PA, USA
1Fortrea Inc., Durham, NC, USA, 2Harmony Biosciences Management Inc., Plymouth Meeting, PA, USA
Presentation Documents
OBJECTIVES: Patients with idiopathic hypersomnia (IH) can exhibit normative, or even prolonged, objectively measured sleep parameters. These objective sleep measures may not appropriately represent key IH symptoms, e.g., excessive daytime sleepiness (EDS), sleep inertia, and cognitive difficulties. Thus, the value of objective sleep measures in evaluating treatment effectiveness is uncertain. The idiopathic hypersomnia severity scale (IHSS) is a PRO that measures three key IH symptom domains and their functional consequences. This qualitative study examined how the content of the IHSS maps to the patient experience of living with IH.
METHODS: Concept elicitation interviews were conducted in a subset of patients (n=61) diagnosed with IH who participated in a clinical trial (Harmony Biosciences: NCT05156047 [N=214]). Trained qualitative researchers used a semi-structured interview guide with open-ended questions to elicit participants’ experience living with IH prior to enrollment in the study. Participants were also asked to rate the relevancy of IHSS item content to their IH condition. Transcripts were analyzed using applied thematic coding techniques to identify salient symptoms of IH.
RESULTS: Baseline characteristics of interviewed and non-interviewed participants were similar (female [80%], White/Caucasian [90%], severe EDS [mean ESS score = 16.2]). Almost all participants described difficulty staying awake or falling asleep during the day (98.3%) that disrupted their daily life (96.7%). Other prevalent symptoms were poor quality of wakefulness (81.6%), morning awakening problems (73.3%), sleep inertia (70.0%), and daytime tiredness (66.7%). Generally, IHSS item content aligned with the experience of living with IH and was “relevant” or “very relevant” to their experience.
CONCLUSIONS: This qualitative study demonstrates that IHSS items map to participant descriptions of their experience of living with IH. Moreover, participants rated the content of IHSS items as relevant to their IH condition. This evidence supports the utility of the IHSS as an endpoint measure for treatment efficacy in IH.
METHODS: Concept elicitation interviews were conducted in a subset of patients (n=61) diagnosed with IH who participated in a clinical trial (Harmony Biosciences: NCT05156047 [N=214]). Trained qualitative researchers used a semi-structured interview guide with open-ended questions to elicit participants’ experience living with IH prior to enrollment in the study. Participants were also asked to rate the relevancy of IHSS item content to their IH condition. Transcripts were analyzed using applied thematic coding techniques to identify salient symptoms of IH.
RESULTS: Baseline characteristics of interviewed and non-interviewed participants were similar (female [80%], White/Caucasian [90%], severe EDS [mean ESS score = 16.2]). Almost all participants described difficulty staying awake or falling asleep during the day (98.3%) that disrupted their daily life (96.7%). Other prevalent symptoms were poor quality of wakefulness (81.6%), morning awakening problems (73.3%), sleep inertia (70.0%), and daytime tiredness (66.7%). Generally, IHSS item content aligned with the experience of living with IH and was “relevant” or “very relevant” to their experience.
CONCLUSIONS: This qualitative study demonstrates that IHSS items map to participant descriptions of their experience of living with IH. Moreover, participants rated the content of IHSS items as relevant to their IH condition. This evidence supports the utility of the IHSS as an endpoint measure for treatment efficacy in IH.
Conference/Value in Health Info
2025-05, ISPOR 2025, Montréal, Quebec, CA
Value in Health, Volume 28, Issue S1
Code
PCR115
Topic
Patient-Centered Research
Topic Subcategory
Instrument Development, Validation, & Translation
Disease
SDC: Neurological Disorders, SDC: Rare & Orphan Diseases