Severe Combined Immunodeficiency (SCID) Clinical Trials

Severe combined immunodeficiency (SCID) represents a group of rare genetic disorders affecting development and function of T lymphocytes and B lymphocytes, essential for adaptive immune responses. Multiple genetic causes exist, including IL2RG (X-linked SCID), ADA deficiency, RAG1/RAG2 deficiencies, and others. Without functional T and B cells, infants are profoundly immunocompromised and susceptible to overwhelming infections from bacteria, viruses, fungi, and parasites.

The most common symptoms of Severe Combined Immunodeficiency include Recurrent, severe infections (bacterial, viral, fungal, parasitic), Severe diarrhea and malabsorption, Failure to thrive, Delayed growth and development, Recurrent infections unresponsive to antibiotics, among others. Severe Combined Immunodeficiency affects approximately 1 in 50,000 to 100,000 births. Symptoms can range from mild to severe and may vary between individuals.

Trial Friend lists all active clinical trials for Severe Combined Immunodeficiency from ClinicalTrials.gov, with eligibility criteria translated into plain English. Patients can filter by trial phase and recruitment status, search by location, and use the Match Me tool to score trials against their profile. SCID research has produced remarkable gene therapy successes for ADA-SCID and IL2RG-SCID, with FDA-approved treatments now available. Research continues expanding gene therapy access to other SCID types and improving outcome predictability.

As of September 2026, Trial Friend's curated drug index does not include an FDA-approved treatment specific to Severe Combined Immunodeficiency. The Treatments section of this page checks FDA drug labels live and lists any approved drug whose label names the condition, and the trials listed below cover the investigational options.

Severe Combined Immunodeficiency is caused by variants in any of many genes, most often IL2RG, ADA, JAK3, RAG1, RAG2 and DCLRE1C. X-linked IL2RG is the single most common form; newborn TREC screening detects most cases before a gene is identified.

It follows X-linked recessive or autosomal recessive depending on gene inheritance. The condition affects approximately 1 in 50,000 to 100,000 births. A multigene panel identifies the cause in most families.

Yes. Severe Combined Immunodeficiency can be caused by variants in many different genes (IL2RG, ADA, JAK3, RAG1, RAG2 and DCLRE1C are among the most common), so testing is usually a multigene panel or exome sequencing rather than one gene at a time. X-linked IL2RG is the single most common form; newborn TREC screening detects most cases before a gene is identified.

It follows X-linked recessive or autosomal recessive depending on gene inheritance.

Knowing the exact gene matters: it decides which trials a patient qualifies for and which relatives should be tested. The labs currently offering the test are listed in the Genetic Testing section of this page, pulled live from the NIH Genetic Testing Registry. A genetic counselor can help interpret the result and decide which relatives should be tested.

Eligibility for Severe Combined Immunodeficiency clinical trials depends on factors like age, diagnosis, treatment history, and overall health. Each trial sets its own inclusion and exclusion criteria. Trial Friend translates these requirements from medical language into plain English so patients can review them more easily. The Match Me tool can score your profile against active trials to help identify studies that may be a fit.

Participating in a Severe Combined Immunodeficiency clinical trial typically involves scheduled visits, medical tests, and close monitoring by a research team. Depending on the study phase, you may receive an investigational treatment, a placebo, or the current standard of care. Trials may last from a few weeks to several years. Study participation is voluntary, and you can withdraw at any time.