Global Gene Therapy Clinical Trial for

 Severe Leukocyte Adhesion Deficiency-I (LAD-I)

What is Leukocyte Adhesion Deficiency-I (LAD-I)? 

LAD-I is a rare genetic disorder affecting the immune system caused by a defect in a single gene known as ITGB2. Patients with severe LAD-I can develop life threatening infections because their white blood cells are unable to leave the bloodstream to fight them. Without a successful bone marrow transplant, severe LAD-I is most frequently fatal during the first 2 years of life.

How does this investigational gene therapy work? 

Blood stem cells are first collected from a patient.  These stem cells are then genetically modified to introduce a correct copy of the ITGB2 gene using a virus that has been changed in the laboratory, so that the virus cannot grow, spread or cause an infection. The gene-modified stem cells are returned back into a patient after the patient receives a type of chemotherapy medication called busulfan to remove existing bone marrow cells to make room for the gene- modified stem cells to grow.

Who is eligible to participate in the LAD-I gene therapy clinical trial? 

Severe LAD-I patients, who are at least 3 months old, and who do not have an available HLA-matched sibling donor for bone marrow transplant.

Where will the LAD-I gene therapy clinical trial be taking place? 

Two clinical centers will be enrolling severe LAD-I patients following very similar protocols:

  1. University of California, Los Angeles (UCLA) in Los Angeles, California, USA  learn more about US Site
  2. Hospital del Niño Jesús in Madrid, Spain learn more about European Site

What does participation in the LAD-I gene therapy clinical trial involve? 

Before patients join the study, they will have to undergo several tests at the clinical center to determine whether they are eligible to join the trial. Following confirmation that a patient meets the eligibility criteria for the trial, participating in the study will involve:

  • Stem Cell Collection: A patient will receive medication to make stem cells enter the blood from the bone marrow. These stem cells have the potential to make different blood cells in the body for the remainder of a patient’s life. The stem cells will be collected from the body through a catheter temporarily placed in a vein. This procedure is called apheresis.
  • Infusion of Genetically Modified Stem Cells (the Investigational Gene Therapy): A patient’s stem cells will be genetically modified in a laboratory to introduce the correct copy of the ITGB2 gene. Prior to receiving the new cells, the patient will receive a chemotherapy medication called busulfan to remove the existing bone marrow cells to make room for the gene-modified cells. The patient will then receive an infusion of the gene-modified cells through the catheter.
  • Follow-up after Administration of the Investigational Gene Therapy: Patients will need to return for follow-up visits, including blood and bone marrow tests, over the next 2 years.  In addition, patients will have long-term follow-up with their home physician approximately 1-2 times per year for another 13 years.

How much will it cost to participate in the trial? 

Financial support, including travel arrangements and housing accommodations for patients and a family member, both for the treatment and follow-up visits, will be provided.  This will also include assistance with passports, medical visas and translation services for patients and families if these are needed.

Who can I contact with additional questions about the clinical trial?

Send any questions to