Cimetidine for Protoporphyria

Recruiting at 2 trial locations

Overseen By Paul Y Jiang

Age: Any Age

Sex: Any

Trial Phase: Phase 2

Sponsor: Amy K. Dickey, M.D.

Must not be taking: Experimental therapies, Cimetidine

Disqualifiers: Liver dysfunction, Renal insufficiency, others

Prior Safety Data This treatment has passed at least one previous human trial

Approved in 4 Jurisdictions This treatment is already approved in other countries

Compensation: Varies

Number of Visits: Unknown

26 Participants Needed

Trial Summary

What is the purpose of this trial?

This trial tests if cimetidine, a common stomach medicine, can help people with EPP and XLP who suffer from painful light sensitivity. The drug might work by stopping the body from making too much of a substance that causes this sensitivity. Cimetidine is often prescribed for hospitalized patients requiring intravenous nutritional support and has been used to prevent excessive fluid and electrolyte loss in patients with short-bowel syndrome.

Research Team

Amy K Dickey, MD

Principal Investigator

Massachusetts General Hospital

Karl E Anderson, MD

Principal Investigator

University of Texas

Eligibility Criteria

This trial is for individuals at least 15 years old with a confirmed diagnosis of Erythropoietic Protoporphyria (EPP) or X-linked Protoporphyria (XLP), who have a history of skin sensitivity to light but are not using other experimental therapies. Participants must be willing to use their smartphone for the study and expose themselves to light weekly.

Inclusion Criteria

I am 15 years old or older.

I am diagnosed with EPP or XLP and enrolled in the PC Study 7201.

I am willing and able to follow the study's procedures and give informed consent.

Exclusion Criteria

I have high porphyrin levels due to liver or bone marrow disease.

You have a known or suspected allergy or intolerance to cimetidine.

I am pregnant, breastfeeding, or planning to become pregnant soon.

Timeline

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Treatment Period 1

Participants receive either placebo or cimetidine for 3 months

3 months

Visits before and after treatment period

Wash-out

A 3-month wash-out period to eliminate carry-over effects

3 months

Treatment Period 2

Participants receive the alternate treatment (cimetidine or placebo) for 3 months

3 months

Visits before and after treatment period

Follow-up

Participants are monitored for safety and effectiveness after treatment

4 weeks

Treatment Details

Interventions

• Cimetidine
• Placebo

Trial Overview The trial is testing if oral Cimetidine can treat protoporphyrias by reducing protoporphyrin levels, improving tolerance to light, and enhancing quality of life. It's compared against a placebo, with outcomes measured through questionnaires and blood tests.

Participant Groups

Group I: Cimetidine Active Control 1 Intervention

Cimetidine 800mg orally twice daily

Group II: Placebo Placebo Group 1 Intervention

Placebo capsule orally twice daily

Cimetidine is already approved in European Union, United States, Canada, Japan for the following indications:

Approved in European Union as Tagamet for:

• Gastroesophageal reflux disease (GERD)
• Peptic ulcer disease
• Zollinger-Ellison syndrome

Approved in United States as Tagamet for:

• Gastroesophageal reflux disease (GERD)
• Peptic ulcer disease
• Zollinger-Ellison syndrome
• Pathological hypersecretory conditions

Approved in Canada as Tagamet for:

• Gastroesophageal reflux disease (GERD)
• Peptic ulcer disease
• Zollinger-Ellison syndrome

Approved in Japan as Tagamet for:

• Gastroesophageal reflux disease (GERD)
• Peptic ulcer disease
• Zollinger-Ellison syndrome

Who Is Running the Clinical Trial?

Amy K. Dickey, M.D.

Lead Sponsor

Trials

1

Recruited

20+

The University of Texas Medical Branch, Galveston

Collaborator

Trials

263

Recruited

55,400+

University of Texas

Collaborator

Trials

193

Recruited

143,000+

Wake Forest University Health Sciences

Collaborator

Trials

1,432

Recruited

2,506,000+