Rocket Pharmaceuticals Announces First Patient Treated in Global Registrational Phase 2 Study of RP-L102 “Process B” for Fanconi Anemia

—Preliminary Phase 2 Data Anticipated in 2020—

NEW YORK–(BUSINESS WIRE)–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 that the first patient in the global Phase 2 registration-enabling study of RP-L102 “Process B” received investigational therapy. RP-L102 is the Company’s lentiviral vector (LVV)-based gene therapy for the treatment of Fanconi Anemia (FA).

“The initiation of Rocket’s first Phase 2 trial is an important milestone for the company as well as patients throughout the world battling FA,” said Kinnari Patel, Pharm.D., MBA, Chief Operating Officer and Head of Development of Rocket. “With the recent feedback received from the FDA and EMA of MMC-resistance as the primary endpoint, we are optimistic about the prospect of benefiting patients and, if the data are positive, working towards BLA and MAA submissions.”

The registrational package will include twelve patients from the U.S. and EU, two from the U.S. Phase 1 study and 10 additional patients from the global Phase 2 study (NCT04069533). Patients will receive a single intravenous infusion of RP-L102 that utilizes fresh cells and “Process B” which incorporates a modified stem cell enrichment process, transduction enhancers, as well as commercial-grade vector and final drug product. Improved mitomycin-C (MMC) resistance in bone marrow colony forming (progenitor) cells is the primary endpoint, and may also serve as a surrogate endpoint for accelerated approval. Additional outcome measures include stability or increase in blood counts with no significant worsening in anemia, neutropenia or thrombocytopenia and peripheral blood and bone marrow genetic correction, as demonstrated by progressive increases in vector copy number (VCN) over the months subsequent to infusion.

Lucile Packard Children’s Hospital Stanford and Hospital Infantil Universitario Niño Jesús are serving as the lead clinical sites and University of Minnesota is conducting centralized evaluation of bone marrow MMC-resistance and engaging in advisory activities for the global trial of RP-L102. RP-L102 was in-licensed from the Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas (CIEMAT), Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Instituto de Investigación Sanitaria Fundación Jiménez Díaz (IIS-FJD) and Fundacion para la Investigacion Biomedica Hospital Infantil Universitario Niño Jesus (FIB-HIUNJ).

About Fanconi Anemia

Fanconi Anemia (FA) is a rare pediatric disease characterized by bone marrow failure, malformations and cancer predisposition. The primary cause of death among patients with FA is bone marrow failure, which typically occurs during the first decade of life. Allogeneic hematopoietic stem cell transplantation (HSCT), when available, corrects the hematologic component of FA, but requires myeloablative conditioning, which is highly toxic for the patient. HSCT is frequently complicated by graft versus host disease and also increases the risk of solid tumors, particularly upper aerodigestive tract squamous cell carcinomas. Approximately 60-70% of patients with FA have a FANCA gene mutation, which encodes for a protein essential for DNA repair. Mutations in the FANCA gene leads to chromosomal breakage and increased sensitivity to oxidative and environmental stress. Chromosome fragility induced by DNA-alkylating agents such as mitomycin-C (MMC) or diepoxybutane (DEB) is the ‘gold standard’ test for FA diagnosis. These assays can further differentiate FA patients from mosaic patients. Somatic mosaicism occurs when there is a spontaneous reversion mutation that can lead to a mixed chimerism of corrected and uncorrected bone marrow cells leading to stabilization or correction of an FA patient’s blood counts in the absence of any administered therapy. Somatic mosaicism provides strong rationale for the development of FA gene therapy and demonstrates the selective advantage of gene-corrected hematopoietic cells in FA¹.

¹Soulier, J.,et al. (2005) Detection of somatic mosaicism and classification of Fanconi anemia patients by analysis of the FA/BRCA pathway. Blood 105: 1329-1336

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 contending 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, and Pyruvate Kinase Deficiency (PKD) a rare, monogenic red blood cell disorder resulting in increased red cell destruction and mild to life-threatening anemia. Rocket’s first clinical program using adeno-associated virus (AAV)-based gene therapy is for Danon disease, a devastating, pediatric heart failure condition. Rocket’s pre-clinical pipeline program is for Infantile Malignant Osteopetrosis (IMO), a bone marrow-derived disorder. For more information about Rocket, please visit www.rocketpharma.com.

Rocket Cautionary Statement Regarding Forward-Looking Statements

Various statements in this release concerning Rocket’s future expectations, plans and prospects, including without limitation, Rocket’s expectations regarding the safety, effectiveness and timing of product candidates that Rocket may develop, to treat Fanconi Anemia (FA), Leukocyte Adhesion Deficiency-I (LAD-I), Pyruvate Kinase Deficiency (PKD), Infantile Malignant Osteopetrosis (IMO) and Danon disease, and the safety, effectiveness and timing of related pre-clinical studies and clinical trials, may constitute forward-looking statements for the purposes of the safe harbor provisions under the Private Securities Litigation Reform Act of 1995 and other federal securities laws and are subject to substantial risks, uncertainties and assumptions. You should not place reliance on these forward-looking statements, which often include words such as “believe,” “expect,” “anticipate,” “intend,” “plan,” “will give,” “estimate,” “seek,” “will,” “may,” “suggest” or similar terms, variations of such terms or the negative of those terms. Although Rocket believes that the expectations reflected in the forward-looking statements are reasonable, Rocket cannot guarantee such outcomes. Actual results may differ materially from those indicated by these forward-looking statements as a result of various important factors, including, without limitation, Rocket’s ability to successfully demonstrate the efficacy and safety of such products and pre-clinical studies and clinical trials, its gene therapy programs, the pre-clinical and clinical results for its product candidates, which may not support further development and marketing approval, the potential advantages of Rocket’s product candidates, actions of regulatory agencies, which may affect the initiation, timing and progress of pre-clinical studies and clinical trials of its product candidates, Rocket’s and its licensors’ ability to obtain, maintain and protect its and their respective intellectual property, the timing, cost or other aspects of a potential commercial launch of Rocket’s product candidates, Rocket’s ability to manage operating expenses, Rocket’s ability to obtain additional funding to support its business activities and establish and maintain strategic business alliances and new business initiatives, Rocket’s dependence on third parties for development, manufacture, marketing, sales and distribution of product candidates, the outcome of litigation, and unexpected expenditures, as well as those risks more fully discussed in the section entitled “Risk Factors” in Rocket’s Quarterly Report on Form 10-Q for the quarter ended September 30, 2019, filed November 8, 2019. Accordingly, you should not place undue reliance on these forward-looking statements. All such statements speak only as of the date made, and Rocket undertakes no obligation to update or revise publicly any forward-looking statements, whether as a result of new information, future events or otherwise.

Contacts

Claudine Prowse, Ph.D.

SVP, Strategy & Corporate Development

[email protected]