Rocket Pharmaceuticals, Inc. announces positive top-line safety and efficacy data from its Phase 2 pivotal trial for severe Leukocyte Adhesion Deficiency-I (LAD-I) at the 25th Annual Meeting of the American Society of Gene and Cell Therapy (ASGCT). Interim Results From an Ongoing Phase 1/2 Study of Lentiviral-Mediated Ex-Vivo Gene Therapy for Pediatric Patients with Severe Leukocyte Adhesion Deficiency-I (LAD-I) The oral presentation includes efficacy and safety data (cut-off March 9, 2022) at three to 24 months of follow-up after RP-L201 infusion for all patients and overall survival data for seven patients at 12 months or longer after infusion. RP-L201 is Rocket's ex-vivo lentiviral gene therapy candidate for severe LAD-I. All patients, aged five months to nine years, demonstrated sustained CD18 restoration and expression on more than 10% of neutrophils (range: 20%-87%, median: 56%).

At one year, the overall survival without allogeneic hematopoietic stem cell transplantation across the cohort is 100% based on the Kaplan-Meier estimate. All patients demonstrated a statistically significant reductionin the rate of all-cause hospitalizations and severe infections, relative to pre-treatment. Evidence of resolution of LAD-I-related skin rashand restoration of wound repaircapabilities has been shown along with sustained phenotypic correction.

The safety profile of RP-L201 has been highly favorable in all patients with no RP-L201-related serious adverse events to date. Adverse events related to other study procedures, including busulfan conditioning, have been previously disclosed and consistent with the safety profiles of those agents and procedures. RP-L201 is an investigational gene therapy product being developed for severe Leukocyte Adhesion Deficiency-I (LAD-I).

The therapy consists of hematopoietic stem cells from the patient that have been genetically modified with a lentiviral vector to contain a functional copy of the ITGB2 gene. RP-L201 is currently being evaluated in a Phase 1/2 clinical trial. The interim analysis of the trial at three to 24 months of follow-up showed RP-L201 had a favorable safety profile and evidence of efficacy with durable CD18 expression.

Severe Leukocyte Adhesion Deficiency-I (LAD-I) is a rare, autosomal recessive pediatric disease caused by mutations in the ITGB2 gene encoding for the beta-2 integrin component CD18. CD18 is a key protein that facilitates leukocyte adhesion and extravasation from blood vessels to combat infections. As a result, children with severe LAD-I are often affected immediately after birth.

During infancy, they suffer from recurrent life-threatening bacterial and fungal infections that respond poorly to antibiotics and require frequent hospitalizations. Children who survive infancy experience recurrent severe infections including pneumonia, gingival ulcers, necrotic skin ulcers, and septicemia. Without a successful bone marrow transplant, mortality in patients with severe LAD-I is 60-75% prior to the age of 2 and survival beyond the age of 5 is uncommon.

There is a high unmet medical need for patients with severe LAD-I.