INVESTOR DECK INVESTOR DECK INVESTOR DECK 41st Annual J.P. Morgan Healthcare Conference Company Presentation Gaurav Shah, MD Chief Executive Officer

INVESTOR DECK INVESTOR DECK INVESTOR DECK 41st Annual J.P. Morgan Healthcare

Conference Company Presentation Gaurav Shah, MD Chief Executive Officer January 9, 2023

DISCLAIMER Various statements in this presentation concerning Rocket's future

expectations, plans and prospects, including without limitation, Rocket's expectations regarding its guidance for 2023 in light of COVID-19, 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), Danon Disease (DD), and other diseases, and the safety, effectiveness and timing of related pre-clinical studies and clinical trials and related data

readouts, 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 monitor the impact of COVID-19 on its business operations and take steps to ensure

the safety of patients, families and employees, the interest from patients and families for participation in each of Rocket's ongoing trials, our expectations regarding when clinical trial sites will resume normal business operations, our

expectations regarding the delays and impact of COVID-19 on clinical sites, patient enrollment, trial timelines and data readouts, our expectations regarding our drug supply for our ongoing and anticipated trials, 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 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 Annual Report on Form 10-K for the year ended December 31, 2021, filed

February 28, 2022 with the SEC and subsequent filings with the SEC including our Quarterly Reports on Form 10-Q. 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.

v To develop first-in-class and best-in-class curative gene therapies for

patients with devastating diseases Generosity Trust Elevate Values Mission Curiosity ABOUT ROCKET PHARMACEUTICALS Vision: Seeking Gene Therapy Cures

Multi-platform, first-and-best in-class approach to treating complex and

life-threatening childhood disorders ???? Late-stage science and innovation Strong capabilities and financials Collaboration and expertise Promising top-line clinical data designed to facilitate US and European registration and launch

with potential for expansion into Asian markets and beyond Therapeutic area focus: Heart and bone marrow Only company with safety and efficacy data for gene therapy targeting the heart US-based in-house facility dedicated to AAV cGMP

manufacturing ~100,000 sq ft Well capitalized to develop full pipeline of assets with $401M1 in cash and cash equivalents; sufficient to fund operations through 2024 Leadership team with proven track record of drug approvals and

launches 20+ World-class scientific experts and partners learning from and collaborating with patient communities Generating Value-based Gene Therapies ABOUT ROCKET PHARMACEUTICALS 1Preliminary, unaudited cash balance as of December 31,

On-target MOA; clear endpoints Sizeable market to maximize patient

impact First-, best- and/or only-in-class Criteria used to select programs 6+ programs with 2 programs fast approaching regulatory filing and launch AAV, adeno-associated virus; ATMP, advanced therapy medicinal product; BLA, Biologics

License Application; LV, lentiviral vector; MAA, Marketing Authorisation Application; MOA, mechanism of action; PRIME, PRIority MEdicines; RMAT, regenerative medicine advanced therapy. PKP2: plakophilin 2; ACM: Arrhythmogenic Cardiomyopathy;

BAG3: BLC2-associated athanogene 3 DCM: Dilated Cardiomyopathy Data on file. Rocket Pharmaceuticals. 2023. Wave 2 programs Fast Track, Orphan Drug (US/EU) DISCOVERY PRECLINICAL PHASE 1 PHASE 2 (Pivotal) Submission and

Approval DESIGNATIONS AAV RP-A501 Danon Disease LV RP-L102 Fanconi Anemia LV RP-L201 Leukocyte Adhesion Deficiency-I LV RP-L301 Pyruvate Kinase Deficiency Multiple Undisclosed Candidates AAV BAG3-DCM THERAPEUTIC AREA AAV RP-A601

PKP2-ACM CARDIOVASCULAR HEMATOLOGY RMAT, ATMP, Fast Track, Rare Pediatric, Orphan Drug (US/EU), PRIME Fast Track, Orphan Drug (US), Rare Pediatric Designation RMAT, ATMP, Fast Track, Rare Pediatric, Orphan Drug (US/EU), PRIME Strong

Science, Carefully-selected Assets and Smart Execution: 6 Disclosed programs with compelling clinical and/or pre-clinical proof of concept ABOUT ROCKET PHARMACEUTICALS

IN VIVO platform EX VIVO platform RP-A501: Danon

Disease RP-A601: PKP2-ACM AAV BAG3-DCM RP-L102: Fanconi Anemia RP-L201: Leukocyte Adhesion Deficiency-I RP-L301: Pyruvate Kinase Deficiency AAV, adeno-associated virus; HSC, hematopoietic stem cell; LV, lentiviral vector. Data on

file. Rocket Pharmaceuticals. 2023 Laboratory- produced AAV Direct intravenous injection Therapeutic AAV Remove cells and isolate patient HSCs Infusion of modified HSCs Therapeutic LV Laboratory-produced LV Gene-modified HSCs All

Rocket therapies transfer full (non-truncated) coding sequence to target tissue ABOUT ROCKET PHARMACEUTICALS Rocket Offers Multi-platform Gene Therapy Expertise

Looking Forward to a Catalyst-Rich 2023 Q1 Completed 2 In-house cGMP Danon

Batches 2023 2024 cGMP, current Good Manufacturing Processes; FA, Fanconi anemia; H1, first half of the year; 2H, second half of the year; LAD-I, leukocyte adhesion deficiency-I; PKD, pyruvate kinase deficiency; Q1, first quarter of the

yearQ2, second quarter of the year; Q3, third quarter of the year; Q4, fourth quarter of the year. Data on file. Rocket Pharmaceuticals. 2023. BAG3 IND Filing FA (C & G) IND Submission Non-Genotoxic Conditioning for LV Additional Wave

2 Assets Disclosed Q2 Q3 Q4 Planned Danon Phase 2 Study Initiation LAD-I Product Filing PKP2-ACM IND Filing Danon EU IMPD Filing FA Product Filing PKD Phase 2 Pivotal Study Initiation Danon Female Study Initiation LAD-I Moderate

Study Initiation ABOUT ROCKET PHARMACEUTICALS Transition from Clinical to Commercial Stage

Standard of care: Heart transplant (HTx) Limitations: Considerable morbidity

and mortality Only ~20% of patients receive HTx Not curative of extracardiac disease Therapeutic Challenges X-linked, dominant, monogenic disease Loss-of-function mutations in LAMP2 Disease

Etiology Impaired autophagy Prominent autophagic vacuoles Myocardial disarray Clinical Manifestations Addressable Market - US and EU Prevalence of 15,000 to 30,000 individuals Annual incidence of 800 to 1,200 individuals Severe

cardiomyopathy Mortality secondary to heart failure or arrhythmia Males: Aggressive disease course, median overall survival: 19 years Females: Delayed median presentation (~20 years later) due to additional X chromosome, highly morbid and

fatal disorder Other clinical manifestations Skeletal myopathy CNS manifestations Ophthalmologic manifestations Danon Disease (DD): Serious Condition with Unmet Medical Need RP-A501: Danon Disease CNS, central nervous system; LAMP-2B,

lysosome-associated membrane protein 2B. Boucek D, Jirikowic J, Taylor M. Natural history of Danon disease. Genet Med. 2011;13(6):563-568. Brambatti M, Caspi O, Maolo A, et al. Danon disease: Gender differences in presentation and outcomes.

Int J Cardiol. 2019;286:92-98.

Non-randomized open label study in male DD patients PRIMARY OUTCOMES 6 to 36

months Enrollment Complete Data Reporting Details Pre-dose (baseline) value defined as the mean values from all visits prior to infusion Core lab data presented for echocardiographic parameters, cardiac serologies and cardiac

histology Phase 1 Study: Treatment Completed RP-A501: Danon Disease Pediatric 8 to 14 years n=2 at CHOP Adults (and Adolescents) >15 years n=5 at UCSD Single intravenous dose of RP-A501 (AAV9.LAMP2B) delivering full coding sequence

of the LAMP-2B gene CHOP, Children's Hospital of Philadelphia; DD, Danon disease; LAMP-2B, lysosome-associated membrane protein 2B; UCSD, University of California San Diego. *No further enrollment at this dose. Due to advanced heart failure

at the time of dosing (LVEF <40%), patient 1007 received a heart transplant 5 months following infusion of RP-A501. Patient is currently stable Cohort Patient ID Age at infusion Time of follow-up (months) Low dose (6.7x1013

GC/kg) Pediatric 1008 12.3 12 1009 11.7 6 Low dose (6.7x1013 GC/kg) Adult and older adolescent 1001 17.4 36 1002 20.3 36 1005 18.3 30 High dose* (1.1x1014 GC/kg) Adult and

older adolescent 1006 21.1 24 1007 20.7 N/A Early and long-term safety Target tissue transduction and LAMP2B protein expression Improved myocardial histology Clinical improvement or stabilization

RP-A501: Danon Disease ADULT COHORT PEDIATRIC COHORT (Low dose) Revised

Immunomodulatory Protocol: More rigorous daily monitoring of labs in initial days following infusion with independent clinical review team Reduced steroid dose with earlier taper Administration of sirolimus and rituximab Low Dose No SAEs

related to drug product: 2 steroid related SAEs (myopathy) High Dose One instance of reversible TMA; led to enhanced RMP One instance of steroid myopathy Platelets remained within normal range No reported skeletal myopathy or late

transaminitis with initial steroid dose reduction and more rapid taper, and introduction of sirolimus Minimal complement activation No complement-related clinical or laboratory AEs All AEs were transient and reversible No treatment-related

SAEs AE, adverse event; SAE, serious AE; TMA, thrombotic microangiopathy. Data cut-off September 27, 2022, with source data verification through July 11, 2022. RP-A501 Demonstrates Favorable Safety Profile With Enhanced Immunomodulation

Protocol All SAEs observed within initial 2-4 months following dosing; reversible with supportive care Both high and low-doses continue to be well tolerated at 2-3 years post treatment No additional SAEs observed following initial 2-4

months No RP-A501-related SAEsAll AEs were transient and reversible, with 8 and 13 months of follow up in 1008 and 1009, respectively

Patient ID Predose Month 6 Month 12 Month

36 1001 0 0.384 0.197 0.120 1002 0 ND 0.575 0.590 1005 0 0.583 ND 1.228 1006 0 2.693 1.131 - 1008 0 0.492 - - 1009 0 Data pending - - LAMP2, lysosome associated membrane protein 2; M, month. IHC =

immunohistochemistry; qPCR = quantitative polymerase chain reaction; ND = not done. The 2nd Cohort 2 pt (1007) underwent heart transplant due to DD progression five months post RP-A501 infusion; data post not included. Pt is currently

clinically stable. 1Derks W, Bergmann O. Polyploidy in Cardiomyocytes: Roadblock to Heart Regeneration?. Circ Res. 2020;126(4):552-565. Note: Cardiomyocytes frequently multinucleated and/or have polyploid nuclei (several genome copies per

cell); however, VCN is calculated assuming one diploid nucleus per cell. As a result, presented VCNs likely underestimated by factor of 2-41; ND. not done, -, visit pending. Corticosteroid compliance uncertain. Month 30 visit. Pediatric

LAMP2 Protein and DNA Suggests Durable Expression As Demonstrated in Adult Cohort RP-A501: Danon Disease LAMP2 Protein Expression (VENDOR) Cardiac LAMP2 DNA by qPCR (vector copies per diploid nucleus) *LAMP2 protein expression assessed

(relative to normal human controls) by core lab in a blinded fashion of entire tissue sample; Percentages reflect estimated extent of LAMP2 staining: Grade 0=negative staining; Grade 1 25%; Grade 2 =26%-50%; Grade 3 =51%-75%; Grade 4

>75%. 1001 1002 1005 1006 1008 1009 4 3 2 1 0 Pre M3 M6 M12 M24 Pre M3 M6 M12 M24 Pre M3 M6 M12 M24 Pre M3 M6 M12 M24 Pre M3 M6 M12 M24 Pre M3 M6 M12 M24 M36 Grade 0 Grade 0 Grade 0 Grade 0 No

Data Grade 0 No Data Grade 0 Grade 0 Oct 2023 Grade 0 March 2023 March 2024 LAMP2 Grade* by IHC LAMP2 Protein Expression M36

Cohort Patient ID Most recent visit (months) hsTnI BNP LV mass LV

max wall thickness NYHA class KCCQ score Low dose pediatric 1008 12 86% 83% 29% 1 15% 1 II -> I +32.3 1009 6 90% 62% 21% 3% II -> I +26 Low dose adult/

adolescent 1001 36 98% 8% 32% 9% II -> II +5.3 1002 36 96% 94% 48% 40% II -> I2 +17.8 1005 30 46% 6% 14% 27% II -> I +8.33 High dose adult/

adolescent 1006 24 63% 69% 27% 15% II -> I +3.1 BNP, brain natriuretic peptide; DD, Danon disease; hsTnI, high-sensitivity troponin I; KCCQ, Kansas City Cardiomyopathy Questionnaire; LAMP2,

lysosome-associated membrane protein 2; LV, left ventricle; NYHA, New York Heart Association. Does not include pt 1007 in Ph1 trial who had advanced HF with EF<40% at enrollment and received HTx 5M following tx due to pre-existing advanced

HF. Patient is currently stable. 11008 echocardiographic parameters are M9 visit (M12 pending). 21002 NYHA class depicted for M30 visit (M36 pending). 31005 KCCQ score depicted for M24 visit (M30 pending). Darker Green = improved; Lighter

Green = minimal change (stabilization) Improvement or Stabilization Observed Across Key Biomarker, Echo Findings and Functional Measures in Phase 1 RP-A501 Study RP-A501: Danon Disease

Note: Graphs do not depict serologic values during initial months after therapy;

BL, baseline; M, month. Does not include pt 1007 in Ph1 trial who had advanced HF with EF<40% at enrollment and received HTx 5M following tx due to pre-existing advanced HF. Patient is currently stable. Indicates normal range

(>100pg/mL BNP; >0.04ng/mL Troponin-I) Improvement or Stabilization Observed Across Key Cardiac Biomarkers RP-A501: Danon Disease

RP-A501 Phase 1 Patients: Marked Divergence from Natural History in Key

Biomarkers RP-A501: Danon Disease Note: aNT-proBNP tends to be higher than corresponding bBNP values given longer plasma half-life. External comparator data from prospective natural history (#s 3,4,6,7,8,9), natural history (DD53) and screen

failure from Phase I study (1010). Phase I graph only reflects BNP levels and does not depict serologic values prior to initial 6 months after therapy. Does not include pt 1007 in Ph1 trial who had advanced Hf with EF<40% at enrollment and

received HTx 5M following tx due to pre-existing advanced HF. Patient is currently stable. RP-A501 Phase 1Baseline & Timepoints 6 months ULN NT-proBNP (125pg/mL) ULN BNP

(100pg/mL) 17.5y 20.4y 18.3y 21.1y 12.3y 11.7y 1001 1002 1005 1006 1008 1009 Note: All values for RP-A501 Phase I patients are BNP levels Sample Pediatric and Adolescent External

Comparators Pt#4a 8.8y Pt#6a 10.6y Pt#8a 13.7y DD53b 12.1y 1010b 13.8y Pt#7a 17.8y Pt#9a 19.5y Pt#3a 9.8y #8: Received HTx 3M following this timepoint #6: Placed on HTx list 11M following this timepoint; M36 &

pre-transplant BNP pending (likely increased) DD53: Placed on HTx list ~3.5yrs following this timepoint #7: Entered Ph1 Trial (1005) #3: Entered Ph1 Trial 8M following this visit (1008) 1010: Received HTx ~2M following this timepoint #4:

Progressed NYHA Class II to III & Significant decrease in KCCQ (28pts) #9: Entered Ph1 Trial (1007*)

Improvement 1 NYHA Class No changein NYHA Class Deterioration 1 NYHA

Class Prospective Natural History Cohort1 RP-A501 Phase 1 Treated Patients (LVEF>40%) n=6 8-36m f/u n=6 6-24m f/u Age 11.7-21.1y2 Age 8.1-19.5y Indicates pts with LVEF 40% at enrollment inprospective Nat Hx study or RP-A501 Phase

1 Indicates pts with LVEF 40% at enrollment inRP-A501 Phase 1; unmonitored immunomodulation Prospective Natural History: No patients had improved NYHA Class RP-A501: All patients with baseline LVEF 40% and monitored immunomodulation had

improved NYHA Class (from Class II at baseline to Class I) Note: Does not include pt 1007 in Ph1 trial who had advanced HF with EF<40% at enrollment and received HTx 5M following tx due to pre-existing advanced HF. Patient is currently

stable. 1Prospective natural history cohort: Sequential NYHA information was available for 6 of 9 patients in cohort. For remaining 3 patients, 1 was lost to follow-up, one received heart transplant (presumably deteriorated), and one was

enrolled in the Phase 1 study. 2RP-A501: Pediatric patients age 11.7 and 12.3 years at rx; all other pts age 17.4-21.1 years at rx. NYHA Class in Danon Disease Male Patients: Natural History versus RP-A501 Phase 1 RP-A501: Danon Disease

Insights from Danon Disease Patients Treated on the Phase 1 Trial RP-A501: Danon

Disease He went to overnight summer camp on his own for the first time and is no longer out of breath walking up stairs. -Pt 1008 Prior to therapy, he was afraid of dying and wanted a chance at life......After gene therapy, we see him smile

more now, he bought his own place and working a couple of days a week, he has started to open up for meeting more friends in real life and has gotten a whole new peace of mind now ...he feels better, and he didn't think that would ever happen

-Pt 1006 He walked a 10K with his father following treatment. He is exercise training twice a week for an hour. -Pt 1009 He can walk upstairs without being short of breath or having to stop half-way. He doesn't have chest pain or fast heart

rates like he used to. Another amazing thing we have seen is about 4 months after his therapy trial he started working and stopped using his motorized scooter altogether. -Pt 1005

Based on End of Phase I Regulatory Discussion and ongoing dialogue with FDA.

Elements in Discussion Key Agreements Reached with FDA 6.7x1013 GC/kg dose Single-arm, open-label study (randomization not appropriate) Support for use of natural history as external comparator information Potential for accelerated

approval based on a composite biomarker-driven endpoint 6MWT, CPET are not appropriate endpoints in DD Specific components of composite endpoint including LAMP2 expression Trial duration and time to endpoint 2 patient run-in for pediatric