A Study to Learn About the C1-Inhibitor Function as Diagnosis for Hereditary Angioedema

Official title

A Prospective, Open- Label, Single-country (Algeria), Interventional Study to Assess Measurements of Functional C1-inhibitor Alone for Hereditary Angioedema Diagnosis: The AHAE Study

Overview

Hereditary angioedema (HAE) is a rare condition. It causes sudden swelling under the skin and inside the body, like in the belly, throat, or genitals. This swelling happens because of a temporary leak in blood vessels but does not cause itching or hives. HAE is classified based on the amount of a protein in the blood called C1-inhibitor (C1INH): HAE with normal C1INH levels and function (HAE-nC1INH) and HAE with deficiency in C1INH levels (HAE-C1INH-Type1) or dysfunction (HAE-C1INH-Type2). This study will focus on the practical use and accuracy of measuring the C1INH function alone to diagnose HAE-C1INH-Type1 and HAE-C1INH-Type2 compared to the tests used in normal clinical practice in Algeria. The main goal of the study is to see how well a test focusing on the C1INH function alone works to diagnose HAE-C1INH as compared to the tests used in normal clinical practice (standard of care or SoC) in Algeria. Another aim is to determine a reference value (helps in determining the accuracy) of the C1INH function test. This study will also help to find out how many people who are thought to have HAE or who have family members with HAE actually get diagnosed and to gather participants' health background information, such as their age when they were diagnosed, what signs and symptoms they had, how long it took to get diagnosed, and how they were sent to the doctors or specialists who treated them. During the study all participants will undergo two different methods of HAE testing: the test focusing on the C1INH function alone and the SoC tests. Test results will be confirmed via a second test run for newly index cases or for discordant results, but participants with a test result of "no HAE" and positive cases recruited through family screening will not undergo a second confirmatory test. In case of discordant test results in the second round, participants will undergo a third confirmatory test round. Participants can visit the clinic up to three times during the study. No further follow up is planned for participants, even for those who are diagnosed with HAE.

Interventions

• Diagnostic test Technochrom C1-INH Kit
  HAE biological diagnostic test that uses functional C1-INH technique by colorimetric method versus the reference test defined as the SoC (C4 and C1-INH antigenic level measurement and functional C1-INH assay).

Primary outcome measures

• Sensitivity and Specificity of Technochrom Compared to Standard of Care (SoC) for HAE Diagnosis [Time frame: Up to 12 months]

Secondary outcome measures (8)

• Laboratory-specific Cut-off Values for Functional C1-INH Measurement Using Technochrom [Time frame: Up to 12 months]
• Sensitivity and Specificity of Technochrom Compared to Isolated Complement Component Test (C4 assay) for HAE Detection [Time frame: Up to 12 months]
• Likelihood Ratios of Technochrom Compared to Isolated C4 Assay for HAE Detection [Time frame: Up to 12 months]
• Sensitivity and Specificity of Technochrom Compared to C4 Assay and C1-INH Antigenic Testing [Time frame: Up to 12 months]
• Likelihood Ratios of Technochrom Compared to C4 Assay and C1-INH Antigenic Testing [Time frame: Up to 12 months]
• Diagnostic Performance of Technochrom in Detecting Functional C1-INH Deficiency and its Impact on Accuracy and Reliability in Clinical Practice [Time frame: Up to 12 months]
• Number of Participants Categorized by Their Epidemiological, Clinical and Biological Characteristics [Time frame: Up to 12 months]
• Diagnostic Rate of Functional C1-INH Deficiency Using Technochrom in Highly Suspected Participants and Family Screening [Time frame: Up to 12 months]

Eligibility criteria

Inclusion criteria

• Adult and pediatric participants of both sexes (children over the age of 12 years).
• Participants providing a signed informed consent form (ICF), or parental consent for minors.
• Participants should also meet one of the 2 inclusion criteria below:

• Participants with a high suspicion of bradykinin-mediated HAE, referred to the center. This includes recurrent episodes of nonpitting angioedema without urticaria or itching, lasting between 1 and 5 days, and non-responsive to antihistamine and corticosteroid treatments.
• Family members (from 1st to 4th degree relatives) of known HAE participants.

Exclusion criteria

• Confirmed diagnosis of HAE-C1INH-Type1 or HAE-C1INH-Type2.
• Angioedema with urticaria or itching (suggesting histaminergic etiology).
• Angioedema episodes lasting less than (<)1 day or greater than (>)5 days (not consistent with bradykinin-mediated HAE).
• Any condition deemed unsuitable by the investigator that may interfere with study procedures or data integrity.

Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.

Healthy volunteers: No

Study design

Allocation

N/A

Model

Single group

Masking

Open label

Primary purpose

Diagnostic

Study locations

Algeria · 1 center

• EPH de Rouiba (Etablissement Public Hospitalier) — Algiers

Identifiers

NCT: NCT07293364 · TAK-743-4028

Primary sources (government registries)

• ClinicalTrials.gov (US NIH)

View this study on ClinicalTrials.gov ↗