NCT01561157 · The American Porphyrias Expert Collaborative
Longitudinal Study of the Porphyrias
What this study is about
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.
View original scientific description
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.
Who can participate
This study lists these criteria on ClinicalTrials.gov. A study coordinator reviews eligibility during screening — this page does not determine whether you qualify.
Inclusion criteria
- Individuals with a documented diagnosis of a porphyria.
- For each type of porphyria, the inclusion criteria are based on
- Biochemical findings, as documented by laboratory reports (or copies) of porphyria-specific testing performed after 1980 (Absolute values are preferred for diagnostic biochemical thresholds. Fold increases in comparison to an upper (or lower) limit of normal (ULN or LLN) are also acceptable, but are complicated by considerable variation between laboratories in normal limits. Equivocal biochemical measurements may require confirmation by a consortium reference laboratory;)
- molecular findings documenting the identification of a mutation in a porphyria-related gene.
- In addition, an individual or a parent or guardian must be willing to give written informed consent or assent, as appropriate.
- Provision is made for enrolling relatives who may not have symptoms but have biochemical or molecular documentation of a porphyria, or in the case of recessive disorders carry a disease-related mutation.
Exclusion criteria
- Cases with elevations of porphyrins in urine, plasma or erythrocytes due to other diseases (i.e. secondary porphyrinuria or porphyrinemia), such as liver and bone marrow diseases;
- Patients with a prior diagnosis of porphyria that cannot be documented by review of existing medical records or repeat biochemical or DNA testing.
Where
- Birmingham, Alabama
- Los Angeles, California
- San Francisco, California
- Miami, Florida
- Chicago, Illinois
- Boston, Massachusetts
- Minneapolis, Minnesota
- New York, New York
- Charlotte, North Carolina
- Winston-Salem, North Carolina
- Cleveland, Ohio
- Philadelphia, Pennsylvania
And 4 more locations — see the full list below.
Frequently asked questions
What is a clinical trial?
A clinical trial is a research study that tests new medical treatments, drugs, devices, or procedures to determine their safety and effectiveness. Trials are carefully designed and monitored to protect participants while advancing medical knowledge.
Is it safe to participate?
Clinical trials follow strict safety guidelines and ethical standards. Trials must be reviewed and approved, and participants are closely monitored by medical professionals throughout the study. You can withdraw at any time if you choose.
Will I be compensated?
Many clinical trials offer compensation for your time, travel expenses, and inconvenience. The specific compensation varies by study and will be discussed during the screening process. All study-related medical care is typically provided at no cost to participants.
Will I receive a placebo instead of treatment?
When effective treatment exists, participants typically receive either the standard treatment plus the study intervention, or the standard treatment plus placebo. You would not be denied effective care. Placebos are primarily used when no proven treatment is available, or in addition to standard care. Your trial consent form will clearly explain what treatments you may receive.
Can I leave a trial if I change my mind?
Absolutely. Participation in clinical trials is completely voluntary. You have the right to withdraw from the study at any time, for any reason, without penalty or loss of benefits to which you are otherwise entitled.
How long does a clinical trial last?
Trial duration varies widely depending on the study design and purpose. Some trials last just a few weeks, while others may continue for months or years. The study coordinator will provide specific timeline information during your screening call.
Data: ClinicalTrials.gov · synced May 15, 2026 · Source of record for eligibility and locations