Bitopertin treatment for Erythropoietic Protoporphyria and X-Linked Protoporphyria

APOLLO: A Randomized, Double-Blind, Placebo-Controlled Study of Bitopertin to Evaluate the Efficacy, Safety, and Tolerability in Participants With Erythropoietic Protoporphyria (EPP) or X-Linked Protoporphyria (XLP)

Phase 3 Interventional Disc Medicine, Inc · NCT06910358

This study is testing if a new medication called bitopertin can help people aged 12 and older with Erythropoietic Protoporphyria or X-Linked Protoporphyria spend more time in the sun without pain.

Quick facts

PhasePhase 3
Study typeInterventional
Enrollment150 (estimated)
Ages12 Years and up
SexAll
SponsorDisc Medicine, Inc Industry-sponsored
Locations4 sites (Huntington Beach, California and 3 other locations)
Trial IDNCT06910358 on ClinicalTrials.gov

What this trial studies

This clinical trial investigates the efficacy and safety of bitopertin in treating participants aged 12 years and older with Erythropoietic Protoporphyria (EPP) or X-Linked Protoporphyria (XLP). The primary objectives include assessing whether bitopertin can increase pain-free sunlight exposure after six months of treatment and evaluating changes in PPIX concentration levels. Participants will be randomly assigned to receive either bitopertin or a placebo, and they will complete daily questionnaires and attend study visits for assessments throughout the trial.

Who should consider this trial

Good fit: Ideal candidates for this study are individuals aged 12 years or older diagnosed with EPP or XLP.

Not a fit: Patients with other forms of porphyria or those who do not meet the eligibility criteria may not benefit from this study.

Why it matters

Potential benefit: If successful, this treatment could significantly improve the quality of life for patients with EPP or XLP by allowing them to have increased sunlight exposure without pain.

How similar studies have performed: Previous studies have shown promise in treating similar conditions, but the specific use of bitopertin in this context is novel.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

1. Aged 12 years or older at the time of study consent.
2. Diagnosis of EPP or XLP, based on medical history by ferrochelatase (FECH) or aminolevulinic acid synthase 2 (ALAS2) genotyping or by biochemical porphyrin analysis.
3. Minimum daily Sun Exposure Diary compliance ≥85% on Days -14 through Day -1, inclusive, during screening, and at least 1 successfully completed Sun Exposure Challenge (adults only, as this assessment is optional for adolescents) or historical recall of time to prodrome
4. Body weight ≥32 kg (ages 12 to \<18 years), body mass index ≥18.5 kg/m2 (ages ≥18 years) at screening.
5. Washout of at least 2 months prior to screening of afamelanotide and dersimelagon, if applicable.
6. Aspartate aminotransferase and alanine transaminase \<3× upper limit of normal (ULN)and total bilirubin \<2× ULN (unless documented Gilbert syndrome) at screening. Albumin \>lower limit of normal (LLN).
7. Willing to practice highly effective methods of birth control (both males who have partners of childbearing potential and females of childbearing potential during screening, while taking study drug, and for at least 30 days after the last dose of study drug).

Exclusion Criteria:

1. Major surgery within 8 weeks before screening or incomplete recovery from any previous surgery.
2. Other than EPP or XLP, an inherited intrinsic or extrinsic red cell disease associated with anemia.
3. Known hypersensitivity to any component of the study drug.
4. History of liver transplantation or anticipated need for liver transplantation.
5. History of alcohol dependence or excessive alcohol consumption, as assessed by the Investigator.
6. Active human immunodeficiency virus (HIV), active hepatitis B or C.
7. Other medical or psychiatric condition or laboratory finding not specifically noted above that, in the judgment of the Investigator or Sponsor, would put the participant at unacceptable risk or otherwise preclude the participant from participating in the study.
8. Condition or concomitant medication that would confound the ability to interpret clinical, clinical laboratory, or participant diary data, including a major psychiatric condition that has had an exacerbation or required hospitalization in the last 6 months.

   Treatment History:
9. Prior exposure to bitopertin.
10. Concurrent or planned treatment with afamelanotide or dersimelagon during the study period.
11. Treatment with opioids for any period \>7 days in the 2 months prior to screening or anticipated to require opioid use for \>7 days at any point during the study.
12. New treatment for anemia, including initiation of iron supplementation, within 1 month of screening.
13. Current or planned use of any drugs or herbal remedies known to be strong or moderate inhibitors or inducers of cytochrome P450 (CYP)3A4 enzymes for 28 days prior to the first dose and throughout the study.
14. Current or planned treatment with antipsychotic medication.

    Laboratory Exclusions:
15. Hemoglobin \<10 g/dL at screening.

    Miscellaneous:
16. Participation in other interventional clinical studies within 30 days prior to screening.
17. If female, pregnant or breastfeeding.

Where this trial is running

Huntington Beach, California and 3 other locations

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions Erythropoietic ProtoporphyriaX-Linked ProtoporphyriaEPPXLPDISC-1459RO4917838porphyria
Last reviewed 2026-06-13 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.