NCT05883748Phase 2, phase 3Enrolling by invitation

HELIOS: Open-Label, Long-Term Extension Study to Investigate the Safety, Tolerability, and Efficacy of DISC-1459 (Bitopertin) in Participants With EPP or XLP

Study sponsor: Disc Medicine, Inc · IRON

Compare the available registry edits below. Primary completion is the date data collection ends for the main study measures; it does not tell you when results will be published.

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Primary completion2028-06Estimated

Enrollment · participants230Estimated

Source updated2026-09-10Last update listed in the registry record

Version history

Changes to this trial

Last 12 months

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Posted 2025-12-18 · 1 field changed

Enrollment · participant count

Recorded edit

− Previous value

count: 200; type: ESTIMATED

+ Updated value

count: 230; type: ESTIMATED

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Study details

Conditions studied

Erythropoietic Protoporphyria

Treatments or interventions studied

DISC-1459DrugAlso known as Bitopertin, RO4917838
DISC-1459DrugAlso known as Bitopertin, RO4917838

Primary outcomes · main study measures

Read the study measures

measure: Incidence of treatment-emergent adverse events; timeFrame: up to 5 Years; measure: Incidence of clinically abnormal vital signs; timeFrame: up to 5 Years; measure: Incidence of clinically abnormal physical exam; timeFrame: up to 5 Years; measure: Incidence of abnormal laboratory test results; timeFrame: up to 5 Years; measure: Assessment of Patient Health Questionnaire (PHQ-8); description: The Patient Health Questionnaire (PHQ-8), an 8-item participant-report measure for screening for depression and for establishing depression severity. The total score ranges from 0-24, with a higher score indicating greater depression symptom severity.; timeFrame: up to 5 Years; measure: Assessment of C-SSRS; description: The C-SSRS is a clinician-rated scale that assesses suicidality from ideation to behaviors and monitors the potential emergence of suicidality in clinical studies.; timeFrame: up to 5 Years

History coverage

Research sample: selected versions from May 2023 onward plus a preceding baseline where available. Only selected fields were retained; endpoint measures were truncated to 300 characters. This is not complete trial or sponsor history. Daily snapshots begin when collection starts.

How to read this history