10 Clinical Trials for Various Conditions
OBJECTIVES: I. Determine the phenotypic heterogeneity of patients with genetic disorders including their clinical spectrum and natural history. II. Develop and evaluate novel methods for the treatment of genetic disorders including metabolic manipulation, enzyme manipulation, enzyme replacement, enzyme transplantation, and gene transfer techniques in these patients. III. Develop and evaluate methods for the prenatal diagnosis of genetic disorders using improved cytogenetic, biochemical, and nucleic acid techniques and amniotic fluid cells or chorionic villi in these patients.
The purpose of this study is to identify the biochemical/genetic defects in erythropoietic protoporphyria (EPP). People with EPP have skin sensitivity to sunlight and occasionally develop liver disease. In this study, the investigators hope to learn the nature of the biochemical/genetic defects in EPP because this may help explain the severity of these clinical features.
In the medical literature there are conflicting reports on whether iron improves symptoms in patients with EPP and XLP. Giving iron to people who are iron deficient is thought to improve EPP symptoms. However, this has never been systematically tested. Therefore, the purpose of this study is to determine the effect of oral iron for EPP and XLP patients.
The initial objective of this protocol is to assemble a well-documented group of patients with confirmed diagnoses of the erythropoietic protoporphyrias, including autosomal recessive Erythropoietic Protoporphyria (EPP) and X-Linked Protoporphyria (XLP) for clinical, biochemical, and genetic studies. The long-term objectives are (1) to conduct a longitudinal investigation of the natural history, complications, and therapeutic outcomes in people with erythropoietic protoporphyria, (2) to systematically investigate the psychological effects of the erythropoietic protoporphyrias on children and adults, and (3) to investigate the correlation between the identified genotypes and the resulting clinical presentation, also determining the possible interaction of other genetic markers.
The objective of this protocol is to conduct a longitudinal multidisciplinary investigation of the human porphyrias including the natural history, morbidity, pregnancy outcomes, and mortality in people with these disorders.
In erythropoietic protoporphyria there is an accumulation of protoporphyrin IX (PPIX) in the plasma and liver. The reason it builds up is either the last step to make heme, insertion of iron into PPIX, is rate limiting or there is an increase in activity in the first step in the heme pathway. It may be possible to decrease the amount of PPIX made and see a decrease in symptoms. The first step to make heme is the key step in the pathway and it uses vitamin B6 as a cofactor. If the investigators can limit the amount of vitamin B6 the investigators can possibly reduce the activity of this rate limiting step. With decreased activity of the enzyme it may be possible for the body to utilize all the PPIX that is made so that none builds up.
The investigators demonstrated that cholestyramine is an effective binding agent in vitro for porphyrins. A few isolated case reports of treatment of individuals with a cutaneous porphyria suggest that cholestyramine and colestipol effectively remove porphyrins. Hypothesis: orally administered colestipol will effectively reduce sun sensitivity and lower erythrocyte porphyrin concentrations in subjects with erythropoietic protoporphyria (EPP).
The goal of this clinical trial is to learn if bitopertin works and is safe to treat EPP or XLP in participants 12 years or older. The main questions it aims to answer are: * Whether bitopertin increases pain-free sunlight exposure after 6 months of treatment in participants with EPP or XLP. * How PPIX concentration levels change from before bitopertin treatment to after 6 months of treatment. Researchers will compare bitopertin to a placebo look-alike substance that contains no drug. Participants will complete daily questionnaires and attend study visits for assessments.
This is an open-label, long-term extension study to investigate the safety, tolerability and efficacy of DISC-1459 in participants with EPP.
This is a Phase 2, multi-center, double-blind, placebo-controlled, parallel group study of bitopertin to evaluate the safety, tolerability, efficacy, and PPIX concentration change in participants with EPP. Participants may roll over to an open label extension portion after completing the double-blind treatment period.