—Preliminary Data from First Patient Demonstrates Initial Safety and Tolerability of RP-L301, Near Doubling of Hemoglobin to Normal Range and Additional Normalization of Hemolysis Markers—

—Rocket’s Largest Lentiviral Pipeline Program Aims to Address Unmet Need for up to 8,000 PKD Patients in the U.S. and Europe—

NEW YORK, NY, USA I December 6, 2020 I Rocket Pharmaceuticals, Inc. (NASDAQ: RCKT) (“Rocket”), a clinical-stage company advancing an integrated and sustainable pipeline of genetic therapies for rare childhood disorders, today announces preliminary clinical data from its Phase 1 clinical trial of RP-L301 for the treatment of Pyruvate Kinase Deficiency (PKD), showing significant improvement in hemoglobin levels and transfusion independence over the initial 3-months following therapy. These results were presented virtually at the 62nd American Society of Hematology (ASH) Annual Meeting in a poster presentation.

“The positive preliminary clinical results for RP-L301 point to a potential path to transform the management of PKD using an approach that addresses the root cause of the disease for the first time at the genetic level,” said Gaurav Shah, M.D., Chief Executive Officer and President of Rocket. “RP-L301 has the potential to normalize hemoglobin levels, as demonstrated by an increase from an average of 7.4 g/dL (at baseline) to 14.3 g/dL (at 3-months post-treatment) with no transfusion requirements after hematopoietic reconstitution in the first patient treated. This patient exhibited a peripheral blood VCN of 2.21 at 1-month post-treatment, suggesting robust and rapid engraftment. Circulating bilirubin and other markers of hemolysis also normalized. We look forward to progressing the study and presenting longer-term data in the second half of 2021. We remain focused on our mission of relieving suffering for PKD patients who are frequently transfusion-dependent and debilitated from the disease and its treatments.”

Key findings from the poster presentation are highlighted below. To access the presentation please visit: https://www.rocketpharma.com/ash-presentations/

Lentiviral Mediated Gene Therapy for Pyruvate Kinase Deficiency: A Global Phase 1 Study for Adult and Pediatric Patients

The data presented in the poster presentation are from two adult patients with significant anemia and transfusion requirement. Patient L301-006-1001 was treated with RP-L301, Rocket’s ex vivo lentiviral gene therapy candidate for PKD. Patient L301-006-1001 was 31-years old at the time of enrollment and had been followed for 3-months post treatment at the time of data cutoff. Patient L301-001-1002 was 47-years old at the time of enrollment and was recently treated. Key highlights from the presentation include:

  • RP-L301 was well tolerated, with no serious safety issues or infusion-related complications observed 3-months post treatment
  • Patient L301-006-1001 received a cell dose of 3.9×106 cells/kilogram (kg) with a drug product mean vector copy number (VCN) of 2.73
    • Hematopoietic reconstitution in less than 2 weeks
    • Peripheral blood VCN of 2.21 at 1-month, normalized hemoglobin (Hb) and hemolysis markers (baseline Hb ~7.4 grams (g)/deciliter (dL); Hb 14.3 g/dL at 3-months post treatment with RP-L301)
    • No red blood cell transfusion requirements following engraftment
      • In the two years prior to enrollment, the patient underwent approximately 14 transfusion episodes
    • Normalization of bilirubin, lactate dehydrogenase (LDH) and erythropoietin levels at 3-months post treatment, each of which had been substantially elevated prior to study enrollment
  • Patient L301-006-1002 was recently treated with RP-L301
    • The patient received a cell dose of 2.4×106 cells/kg with a mean drug product VCN of 2.08

Aspects of the RP-L301 pre-clinical data package, including phenotypic reversal in the murine PKD knockout model, were also reviewed.

Conference Call Details Rocket management will host a conference call and webcast on December 7, at 6:00 p.m. EST. To access the call and webcast, please click here. The webcast replay will be available on the Rocket website following the completion of the call.

Investors may listen to the call by dialing (866) 866-1333 from locations in the United States or +1 (404) 260-1421 from outside the United States. Please refer to conference ID number 50038102.

About Pyruvate Kinase Deficiency

Pyruvate kinase deficiency (PKD) is a rare, monogenic red blood cell disorder resulting from a mutation in the PKLR gene encoding for the pyruvate kinase enzyme, a key component of the red blood cell glycolytic pathway. Mutations in the PKLR gene result in increased red blood cell destruction and the disorder ranges from mild to life-threatening anemia. PKD has an estimated prevalence of 3,000 to 8,000 patients in the United States and the European Union. Children are the most commonly and severely affected subgroup of patients. Currently available treatments include splenectomy and red blood cell transfusions, which are associated with immune defects and chronic iron overload.

RP-L301 was in-licensed from the Centro de Investigaciones Energeticas, Medioambientales y Tecnologicas (CIEMAT), Centro de Investigacion Biomedica en Red de Enfermedades Raras (CIBERER) and Instituto de Investigacion Sanitaria Fundacion Jimenez Diaz (IIS-FJD).

About Rocket Pharmaceuticals, Inc.

Rocket Pharmaceuticals, Inc. (NASDAQ: RCKT) (“Rocket”) is advancing an integrated and sustainable pipeline of genetic therapies that correct the root cause of complex and rare childhood disorders. The company’s platform-agnostic approach enables it to design the best therapy for each indication, creating potentially transformative options for patients afflicted with rare genetic diseases. Rocket’s clinical programs using lentiviral vector (LVV)-based gene therapy are for the treatment of Fanconi Anemia (FA), a difficult to treat genetic disease that leads to bone marrow failure and potentially cancer, Leukocyte Adhesion Deficiency-I (LAD-I), a severe pediatric genetic disorder that causes recurrent and life-threatening infections which are frequently fatal, Pyruvate Kinase Deficiency (PKD) a rare, monogenic red blood cell disorder resulting in increased red cell destruction and mild to life-threatening anemia and Infantile Malignant Osteopetrosis (IMO), a bone marrow-derived disorder. Rocket’s first clinical program using adeno-associated virus (AAV)-based gene therapy is for Danon disease, a devastating, pediatric heart failure condition. For more information about Rocket, please visit www.rocketpharma.com.

SOURCE: Rocket Pharmaceuticals