Rocket Pharmaceuticals, Inc.: Form 10-Q for the period ended Jun 30, 2025

You should read the following discussion and analysis of our financial condition and results of operations together with the consolidated financial statements and related notes that are included elsewhere in this Quarterly Report on Form 10-Q and our annual report on Form 10-K, filed on February 27, 2025, with the SEC.

Some of the statements contained in this discussion and analysis or set forth elsewhere in this quarterly report on Form 10-Q, including information with respect to our plans and strategy for our business, constitute forward looking statements within the meaning of Section 27A of the Securities Act of 1933, as amended (the "Securities Act"), and Section 21E of the Securities Exchange Act of 1934, as amended (the "Exchange Act"). We have based these forward-looking statements on our current expectations and projections about future events. The following information and any forward-looking statements should be considered in light of factors discussed elsewhere in this quarterly report on Form 10-Q particularly including those risks identified in Part II, Item 1A “Risk Factors” and our other filings with the Securities and Exchange Commission (the "SEC").

Our actual results and timing of certain events may differ materially from the results discussed, projected, anticipated, or indicated in any forward-looking statements. We caution you that forward-looking statements are not guarantees of future performance and that our actual results of operations, financial condition and liquidity, and the development of the industry in which we operate may differ materially from the forward-looking statements contained in this quarterly report on Form 10-Q. Statements made herein are made as of the date of the filing of this Form 10-Q with the SEC and should not be relied upon as of any subsequent date. Even if our results of operations, financial condition and liquidity, and the development of the industry in which we operate are consistent with the forward-looking statements contained in this quarterly report on Form 10-Q, they may not be predictive of results or developments in future periods. We disclaim any obligation, except as specifically required by law and the rules of the SEC, to publicly update or revise any such statements to reflect any change in our expectations or in events, conditions or circumstances on which any such statements may be based or that may affect the likelihood that actual results will differ from those set forth in the forward-looking statements.

We caution readers not to place undue reliance on any forward-looking statements made by us, which speak only as of the date they are made.

Overview

Rocket Pharmaceuticals is a fully integrated, late-stage biotechnology company focused on the development, manufacturing, and potential commercialization of genetic therapies for rare and often fatal diseases with high unmet medical need. Rocket’s innovative multi-platform approach allows for the creation of best-in-class gene therapies aimed at correcting the root cause of complex genetic disorders, spanning across cardiac and hematologic indications, offering the potential for transformative and durable clinical benefits. Rocket’s platform is supported by in-house R&D capabilities and current cGMP facilities that enable end-to-end control over clinical production and scale-up for commercialization.

Our Strategy

We seek to bring hope and relief to patients with devastating, undertreated and rare diseases through the development and commercialization of potentially curative first-in-class gene therapies. As a fully integrated, late-stage biotechnology company, we have the resources and opportunity to generate a portfolio of highly differentiated and potentially first-in-class or best-in-class genetic medicines.

In July 2025, we announced a strategic corporate reorganization and pipeline prioritization aimed at maximizing near-term value, extending operational runway and positioning the company for sustained long-term growth. The restructuring and reprioritization initiative focuses our resources on the AAV cardiovascular platform, as well as submitting the completed responses to the CRL for KRESLADITM and a strategic reprioritization of assets away from the FA and PKD programs. As part of the restructuring, the Company implemented a reduction in the workforce of approximately 30%, which, along with other planned cost-saving initiatives, is expected to reduce Rocket’s 12-month operating expenses by nearly 25%.

Our strategy is built on several foundational pillars:

• First-and-Best-in-Class Approach: With our program selection, we apply a rigorous, disease-based selection approach to identify and prioritize programs: targeting complex genetic disorders with differentiated therapies that offer the potential to be first-, best-, or only-in-class, focusing on monogenic disease with on-target mechanisms of action to directly address the root cause of the disease to offer superior clinical profiles, and choosing indications with sizable market opportunities to enable broad patient impact and sustainable value creation.
• Strategic Focus on Rare Cardiovascular Indications: Our near-term research and platform investments are focused on leveraging our AAV capabilities in rare cardiovascular diseases. Collectively, our clinical cardiovascular gene therapy programs target the major genetically defined causes of hypertrophic, arrhythmogenic, and dilated cardiomyopathies which represent a significant portion of inherited heart disease and impact more than 100,000 patients in the U.S. and EU.
• Late-Stage Science & Innovation with Robust Capabilities: We are advancing promising clinical programs designed to support regulatory approvals in the U.S. and Europe, with potential expansion into Asia and beyond. To support our clinical and future commercial endeavors, we are currently operating a ~100,000 sq. ft. U.S.-based in-house AAV cGMP manufacturing facility in Cranbury, New Jersey.
• Expertise & Collaboration: Our leadership team brings a proven track record of over 20 successful U.S. and international drug approvals and launches with expertise in cell and gene therapies and rare diseases. We collaborate closely with scientific experts, healthcare providers, payors, and patient communities to ensure our therapies address real-world needs.

In the near- and medium-term, we are focused on:

• Advancing our first-in-class product candidates targeting monogenic diseases with substantial unmet need.
• Building proprietary in-house analytics and manufacturing capabilities.
• Conducting registration trials for our lead programs.

In the medium- and long-term, pending favorable data, we plan to:

• Submit BLAs for our suite of clinical programs.
• Expand our gene therapy platform to additional indications compatible with our technologies.
• Pursue potential eligibility for FDA priority review vouchers, pending program renewal by Congress.

Gene Therapy Overview

Gene therapy is a therapeutic approach in which an isolated gene sequence or segment of DNA is administered to a patient, most commonly for the purpose of treating a genetic disease that is caused by genetic mutations. Currently available therapies for many genetic diseases focus on administration of large proteins or enzymes and typically address only the symptoms of the disease. Gene therapy aims to address the disease-causing effects of absent or dysfunctional genes by delivering functional copies of the gene sequence directly into the patient’s cells, offering the potential for curing the genetic disease, rather than simply addressing symptoms.

We are developing gene therapies utilizing modified, non-pathogenic viruses as delivery vehicles. Viruses are inherently effective for gene delivery due to their natural ability to enter cells and deliver genetic material. In engineering our viral vectors, the native viral genes are removed and replaced with a functional copy of the missing or mutated gene responsible for a patient’s genetic disorder. This functional copy, known as the therapeutic gene or “transgene,” is introduced through a process known as transduction. Once modified, the virus is termed a “viral vector,” capable of delivering the transgene to targeted tissues or organs.

We are advancing two categories of viral vectors: AAV vectors and LV vectors. We believe that our AAV- and LV-based programs have the potential to confer significant and durable therapeutic benefits. Our gene therapies are administered either (1) ex vivo, whereby a patient’s cells are collected, transduced with the viral vector in a controlled laboratory environment, and subsequently reinfused into the patient, or (2) in vivo, whereby the viral vector is delivered directly into the patient, either intravenously or through targeted tissue injection, to enable in situ transduction of the desired cell populations.

We believe that scientific advances, clinical progress, and the greater regulatory acceptance of gene therapy have created a promising environment to advance gene therapy products as these products are being designed to restore cell function and improve clinical outcomes, which in many cases include prevention of death at an early age. The FDA approval of several gene therapies in recent years indicates that there is a regulatory pathway forward for gene therapy products.

Pipeline Overview

The chart below shows the current phases of development of our programs and product candidates:

The Company has global commercialization and development rights to all of these product candidates under royalty-bearing license agreements.

Cardiovascular Programs

Danon disease

Danon disease, otherwise known as DD, is a rare X-linked inherited, multi-organ lysosomal-associated disorder with a devastating clinical course. The causative mutation has been identified in the gene encoding for lysosome-associated membrane protein, otherwise known as LAMP2, an important mediator of autophagy and primarily expressed in heart, skeletal muscle and brain tissue. This mutation results in the accumulation of autophagic vacuoles, predominantly in cardiac and skeletal muscles. Male patients often require heart transplantation and typically die during adolescence or early adulthood from progressive heart failure. Along with severe cardiomyopathy, other DD-related manifestations can include skeletal muscle weakness and intellectual impairment. There are no specific therapies available for the treatment of DD and medications typically utilized for the treatment of HF are not believed to modify progression to end-stage HF. Patients with end-stage HF may undergo heart transplant, which currently is available to a minority of patients, is associated with significant short- and long-term complications and is not curative of the disorder in the long-term. It is estimated to have a prevalence of 15,000 to 30,000 patients in the U.S. and Europe.

RP-A501 is our investigational gene therapy for the treatment of DD and consists of a recombinant adeno-associated serotype 9 (AAV9) capsid containing a full-length, wild-type version of the human LAMP2B transgene which is administered as a single intravenous (IV) infusion. RP-A501 holds FDA RMAT, Fast Track, Rare Pediatric, and Orphan Drug designations in the U.S. along with ATMP and PRIME designations in the EU.

We treated seven patients in the single-arm, open-label, multi-center Phase 1 clinical trial assessing the safety and preliminary efficacy of RP-A501, which enrolled adult/older adolescent and pediatric male DD patients. This includes a first cohort evaluating a low-dose (6.7e13 genome copies/kilogram ([gc/kg]; n=3) in adult/older adolescent patients aged 15 or greater, a second cohort evaluating a higher dose (1.1e14 gc/kg; n=2) in adult/older adolescent patients aged 15 or greater, and a pediatric cohort at a low dose level (6.7e13 gc/kg; n=2).

We conducted a variety of efficacy assessments in the Phase 1 clinical study to measure the prospect of benefit for patients. These assessments included the following:

• LAMP2 gene expression in endomyocardial biopsy samples is measured via both immunohistochemistry and Western blot and confirms the presence of LAMP2 protein in DD cardiac tissue following RP-A501 treatment.
• ECG measurements of heart thickness, most notably, left ventricular mass and maximal left ventricular wall

thickness, indicate the degree of hypertrophy present in the heart

• High sensitivity troponin I or hs-TnI and BNP are blood-based evaluations and a key marker of HF and cardiac injury. Both are frequently elevated in DD patients and has been shown to be markedly elevated in patients with advanced stage disease.
• KCCQ is a validated, patient-reported quality-of-life assessment that measures a patient’s perception of their HF symptoms, impact of disease on physical and social function, and the impact of their HF on overall health status and quality of life. Assessment scores range from 0 (very poor health status) to 100 (excellent health status). Changes in KCCQ score of +/- 5 points are considered meaningful and have been shown to correlate with heart failure outcomes.
• NYHA Functional Classification is the most commonly used HF classification system. NYHA Class I reflects the absence of clinical signs of HF, while NYHA Class II is where a patient exhibits a slight limitation of physical activity, is comfortable at rest, and ordinary physical activity results in fatigue, palpitation and/or dyspnea. NYHA Class III and IV are considered more severe or advanced HF.
• Histologic examination of endomyocardial biopsies via hematoxylin and eosin histology and electron microscopy is used to detect evidence of DD-associated tissue derangements, including the presence of autophagic vacuoles and disruption of myofibrillar architecture, each of which are characteristic of DD-related myocardial damage.
• LAMP2 gene expression in endomyocardial biopsy samples is measured via both immunohistochemistry and Western blot and confirms the presence of LAMP2 protein in DD cardiac tissue following RP-A501 treatment.

As previously disclosed, a patient receiving therapy on the high dose cohort (1.1e14 gc/kg dose) had progressive HF and underwent a heart transplant at month five following therapy. This patient had more advanced disease than the four other adult/older adolescent patients who received treatment in the low and high dose cohorts, as evidenced by diminished baseline left ventricle ejection fraction (35%) on echocardiogram and markedly elevated left ventricle filling pressure prior to treatment. The patient’s clinical course was characteristic of DD progression. The patient is doing well post-transplanting.

Based on the initial efficacy observed in the low dose cohort and to mitigate complement-mediated safety concerns observed in the high dose cohort (related to thrombotic microangiopathy or TMA) and in agreement with the FDA, we have moved forward with the low dose (6.7e13 gc/kg). Additional safety measures were implemented and are reflected in the updated trial protocol for Phase 1 and the protocol for our ongoing pivotal Phase 2 study. These measures include exclusion of patients with end-stage HF, and a refined immunomodulatory regimen involving transient B- and T-cell mediated inhibition, with emphasis on preventing complement activation, while also enabling lower steroid doses and earlier steroid taper, with all immunosuppressive therapy discontinued 2-3 months following administration of RP-A501.

In November 2024, we announced positive results and presented long-term safety and efficacy results of the Phase 1 study at the American Heart Association’s 2024 Late-Breaking Science sessions and simultaneously published these data in the New England Journal of Medicine. The long-term safety and efficacy results from the Phase 1 RP-A501 study showed that RP-A501 was generally well tolerated and all evaluable DD patients demonstrated LAMP2 protein expression at 12 months (sustained up to 60 months) and reduction of left ventricular mass index by ≥10% at 12 months (sustained up to 54 months) after treatment. Results from the Phase 1 DD trial represent one of the first and most comprehensive investigational gene therapy datasets for any cardiac condition.

Data from the Phase 1 study (cut-off April 19, 2024) showed that RP-A501 in conjunction with a transient immunomodulatory regimen was generally well tolerated. Evidence of sustained clinically meaningful improvement was observed in pediatric patients followed up to 24 months and adult/adolescent patients followed up to 60 months.

In summary, all evaluable patients in the Phase 1 trial demonstrated:

• Cardiac LAMP2 protein expression at 12 months and thereafter;
• Reduction or stabilization of left ventricular mass index (LVMI) – the median reduction from baseline to most recent visit of 24% (for the ongoing pivotal Phase 2 trial, a 10% reduction in LVMI and positive protein expression of Grade 1 or more are co-primary endpoints);
• Preservation of normal left ventricle ejection fraction (LVEF);
• Reduction or stabilization of cardiac biomarkers (median cardiac troponin I [cTnI] and BNP reductions of 84% and 57%, respectively);
• Improvement in NYHA class from Class II at baseline to Class I at most recent follow-up visit;
• Improvements in KCCQ scores (median improvement of 27 points) that persisted up to 54 months of follow-up; and
• Preliminary long-term follow-up assessments for Patient 1001 were positive for immunohistochemical staining and appear to show Grade 3 expression in the heart at the five-year timepoint. These are preliminary results with a formal update anticipated to be presented at an upcoming medical conference.

In September 2023, we announced that alignment was reached with the FDA on the global Phase 2 pivotal trial of RP-A501 for DD to support accelerated approval. The global, single-arm, multi-center Phase 2 pivotal trial is evaluating the efficacy and safety of RP-A501 in 12 patients with DD, including a pediatric safety run-in (n=2), with a natural history comparator and a dose level of 6.7 x 1013 GC/kg. A global natural history study is also running concurrently to the Phase 2 pivotal trial and will serve as an external comparator.

To support accelerated approval, the study will assess the efficacy of RP-A501 as measured by the biomarker-based co-primary endpoint consisting of improvements in LAMP2 protein expression (≥ Grade 1, as measured by immunohistochemistry), and reductions in left ventricular mass.

Key secondary endpoint is change in troponin. Additional secondary endpoints will include natriuretic peptide, KCCQ, NYHA class, event free survival to 24 months and treatment emergent safety events. These endpoints could support full approval with longer-term follow-up.

Drug product for the Phase 2 study is being produced in-house in our GMP manufacturing facility in Cranbury, NJ. We have successfully produced multiple commercial-grade Danon AAV cGMP batches since 2022. These batches have superior specifications to Phase 1 material in both titer and full versus empty particles. We believe the improved quality of our in-house manufactured product will allow for full dosing with lower total viral particles. Furthermore, we have reached agreement with the FDA on the continued utilization of HEK-293 cell-based process through commercialization, our comparability approach and our potency assay.

In January 2024, we received CTIS approval to include clinical trial sites in certain EU Member States.

In September 2024, we announced completion of enrollment of 12 patients in the Phase 2 study across sites in the U.S. and EU. As previously disclosed, two patients participating in the Phase 2 pivotal study of RP-A501 each experienced an unexpected Serious Adverse Event (SAE). The SAEs involved clinical complications related to a capillary leak syndrome and were followed by a systemic infection and multi-organ damage, ultimately leading to one of the patient’s death. Rocket voluntarily paused further Phase 2 study dosing in the U.S. and EU, and the FDA subsequently placed the trial on clinical hold on May 23, 2025 to allow for further evaluation. Rocket is conducting a comprehensive root cause analysis and remains in active dialogue with the FDA and other key stakeholders, with the current focus being on the recent introduction of a novel immune suppression agent, a C3 inhibitor, to the pre-treatment regimen that had been implemented to mitigate complement activation observed in some Phase 2 patients.

Rocket is working with the FDA, the Independent Data Safety Monitoring Committee, clinical investigators, and scientific experts, and is committed to ensuring the safety of all study patients while resuming the trial as expeditiously as possible. Rocket is committed to transparency and will provide updates as our analysis progresses. However, while the clinical hold remains in place, the company is unable to provide guidance on the anticipated timing for completion of the Phase 2 trial.

Plakophilin-2 Arrhythmogenic Cardiomyopathy

Plakophilin-2 related Arrhythmogenic cardiomyopathy, otherwise known as PKP2-ACM is an inheritable cardiac disorder caused by pathogenic variants in the PKP2 gene that is characterized by a high propensity for arrhythmias and sudden cardiac death. Most commonly, the cardiomyopathy initially manifests in the right ventricular free wall, so the disease was originally termed arrhythmogenic right ventricular dysplasia/cardiomyopathy or ARVD/C. However, since left dominant and biventricular forms have also been observed, this has led more recently to the use of the term ACM. Mutations in the PKP2 gene comprise the most frequent genetically identified etiology of familial ACM. Patients with mutations in PKP2 are typically heterozygous and demonstrate reduced expression of the PKP2 protein in the myocardium. PKP2 encodes for the protein Plakophilin-2, which is a component of the desmosome, an intercellular complex involved in cell-cell adhesion. The PKP2 protein is also involved in transcriptional regulation of calcium signaling between cardiomyocytes. PKP2-ACM is most commonly in young adults with the mean age presentation at 35 years old, and patients have a very high lifetime risk of ventricular arrhythmias, structural ventricular abnormalities, and SCD.

There are no specific available medical therapies available that have been shown to be highly effective for ACM, and current treatment protocols follow standard ventricular arrhythmia and cardiomyopathy guidelines, which involve lifestyle modifications (i.e. exercise limitation) and include drug treatments such as beta blockers, anti-arrhythmics and diuretics. The use of these therapies is driven by the arrhythmia burden and severity of cardiomyopathy. These therapies do not modify the course of the disease and generally provide only symptomatic and/or palliative support. Upon diagnosis, a substantial percentage of patients receive an ICD for primary or secondary prevention of ventricular arrhythmias and SCD. Of note, ICDs are not curative, and breakthrough life-threatening arrythmias may persist with ongoing risk of death. Furthermore, ICDs do not prevent the progression to end-stage HF. ICD firings, although lifesaving, are physically and emotionally traumatic events. Patients whose condition progresses to end-stage HF are considered for cardiac transplantation which, while curative of underlying disease, is itself associated with significant morbidity and mortality. Hence there exists a high unmet medical need in this population. PKP2-ACM is estimated to have a prevalence of 50,000 patients in the U.S. and EU.

RP-A601 is our investigational gene therapy for the treatment of PKP2-ACM and consists of a recombinant adeno-associated serotype rh74 capsid containing a functional version of the human PKP2 transgene (AAVrh74.PKP2) which is administered as a single IV infusion. RP-A601 holds FDA RMAT and Fast Track and designations in the US and Orphan drug designations in both the US and EU.

In May 2023, we presented preclinical efficacy data for RP-A601 at the ASGCT 26th Annual meeting. Nonclinical studies of RP-A601 demonstrated efficacy in altering the natural history of PKP2-driven ACM. 100% of PKP2 conditional knockout (cKO) animals treated with the study drug exhibited extended survival to the longest timepoint measured (5 months), reduced cardiac dilation and fibrofatty replacement/fibrosis of the myocardium, preserved left ventricular function, and mitigation of the arrhythmic phenotype. Untreated PKP2 cKO mice had a median survival of approximately one month. These results were published in January 2024 in the journal Circulation: Genomic and Precision Medicine.

The ongoing single-arm, open-label, multi-center Phase 1 study is evaluating the safety and preliminary efficacy of RP-A601 in adult PKP2-ACM patients with ICDs and overall high risk for arrhythmias. The study is assessing the impact of RP-A601 on PKP2 myocardial protein expression, cardiac biomarkers, and clinical predictors of life-threatening ventricular arrhythmias and SCD. Patients in the Phase 1 study will receive a single dose of RP-A601 starting at 8 x 1013 GC/kg. Enrollment in the U.S. Phase 1 study has completed.

In May 2025, we presented preliminary data from the Phase 1 study of RP-A601 for adult patients with PKP2-ACM at the ASGCT 28th Annual meeting in the Late-Breaking Scientific Sessions. Initial data from the Phase 1 study (safety cut-off May 6, 2025; efficacy cut-off April 2025) showed that RP-A601 was generally well-tolerated with no dose-limiting toxicities observed in all patients (n=3) followed for up to 12 months. Most treatment emergent adverse events were mild/moderate in severity and self-limited with only one patient experiencing SAEs which resolved without clinical sequelae within two months post-treatment, believed to be associated with the immunomodulatory regimen.

Cardiac biopsies showed RP-A601 increased PKP2 protein expression in all three patients. In the patients with low baseline PKP2 expression (N=2), improvements in PKP2 protein expression relative to total cell protein were approximately 110% and 398%, respectively, from baseline to six months follow-up. In all three patients, RP-A601 promoted desmosome localization of PKP2 and associated transmembrane interpolated disc proteins between 3 and 12 months after treatment. In addition, preliminary indications of improvement or stabilization in arrhythmia burden, heart function and quality of life were observed. At this time, we believe that we have reached both the safe and efficacious dose and based on the overall risk benefit seen so far, we are no longer dose escalating in this trial and will move 8 x 1013 GC/kg into the next phase of development.

BAG3 Dilated Cardiomyopathy

DCM is the most common form of cardiomyopathy and is characterized by progressive thinning of the walls of the heart resulting in enlarged heart chambers that are unable to pump blood. A familial association of DCM can be identified in 20-50% of DCM patients, with up to 40% of familial patients having an identifiable genetic cause. Mutations in the BAG3 gene are among the more common pathogenic genetic variants observed in familial DCM and these variants are highly penetrant, with approximately 80% of individuals with disease-causing genetic variants in the BAG3 gene developing DCM at > 40 years of age. Pathogenic variants in BAG3 are estimated to cause from 2.3% to 6.7% of DCM cases in the U.S., Europe, and Japan. BAG3 protein is associated with a variety of cellular functions including cardiac contractility, protein quality control (as a co-chaperone), cardiomyocyte structural support and anti-apoptosis. BAG3-DCM leads to early onset, rapidly progressing heart failure and significant mortality and morbidity. The age of diagnosis in BAG3-DCM varies from adolescence to adulthood, with the mean age at clinical diagnosis in the mid-30s. The prevalence of BAG3-associated DCM in the U.S. is estimated to be as many as 30,000 individuals.

DCM represents a considerable unmet medical need and is the most common underlying diagnosis in patients undergoing heart transplantation. No currently approved therapies are specifically indicated to address BAG3-DCM. Medical management of patients with DCM follows the clinical guidelines for heart failure with reduced ejection fraction (HFrEF), including the use of beta-adrenergic receptor antagonists (beta-blockers), angiotensin converting enzyme (ACE) inhibitors, angiotensin receptor antagonists/neprilysin inhibitors, mineralocorticoid antagonists, and inhibitors of the sodium-glucose cotransporter-2 (SGLT2), along with antiarrhythmic medications, implanted defibrillator, and/or ablation procedures as indicated. Heart transplantation is the only potentially definitive therapy; however, it is not considered curative and is associated with considerable morbidity and mortality. An effective and safe gene therapy to restore normal BAG3 cardiac protein levels may represent a viable therapeutic option which could substantially reduce morbidity/mortality in BAG3-DCM patients. The understanding of the genetic mechanism of disease affords the opportunity to develop precision-based therapies potentially corrective of the underlying molecular defect.

In December 2022, we completed our acquisition of Renovacor which provided the Company with Renovacor’s recombinant AAV9-based gene therapy program designed to deliver a fully functional BAG3 gene to augment BAG3 protein levels in cardiomyocytes and slow or halt progression of BAG3-DCM. Initial proof of concept for AAV9-BAG3 has been demonstrated in studies of BAG3-knockout mouse models, which show treated mice have improved ejection fraction versus untreated knockout mice and comparable ejection fraction to walk test controls at timepoints 4- and 6-weeks post injection. In June 2025, the company received FDA clearance of an IND application for RP-A701, an AAV.rh74-based gene therapy candidate for the treatment of BAG3-DCM. Following, the FDA granted Fast Track designation to RP-A701 for the treatment of BAG3-DCM in July 2025.

Hematology Programs

Leukocyte Adhesion Deficiency-I

LAD-I is a rare autosomal recessive disorder of white blood cell adhesion and migration, resulting from mutations in the ITGB2 gene encoding for the Beta-2 Integrin component, CD18. Deficiencies in CD18 result in an impaired ability for neutrophils (a subset of infection-fighting white blood cells) to leave blood vessels and enter tissues where these cells are needed to combat infections. As is the case with many rare diseases, accurate estimates of incidence are difficult to confirm; however, several hundred cases across the spectrum of severity have been reported to date. Most LAD-I patients are believed to have the severe form of the disease. Severe LAD-I is notable for recurrent, life-threatening infections and substantial infant mortality in patients who do not receive an allogeneic HSCT. Mortality for severe LAD-I has been reported as 60 to 75% by age two in the absence of allogeneic HCST.

KRESLADI™, formally known as RP-L201 or marnetegragene autotemcel, is our investigational gene therapy that contains autologous (patient-derived) hematopoietic stem cells that have been genetically modified with a lentiviral vector to deliver a functional copy of the ITGB2 gene. Rocket holds FDA RMAT, Rare Pediatric, and Fast Track designations in the U.S., PRIME and ATMP designations in the EU, and Orphan Drug designations in both regions for the program. KRESLADI™ was in-licensed from the Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas (CIEMAT), Centro de Investigación Biomédica en Red de Enfermedades Raras and Instituto de Investigación Sanitaria Fundación Jiménez Díaz. The lentiviral vector was developed in a collaboration between University College London and CIEMAT.

The open-label, single-arm, global Phase 1/2 registration-enabling clinical trial of RP-L201 for severe LAD-I treated nine patients. In May 2024, we presented updated follow-up data at the ASGCT 27th Annual Meeting, including 18- to 45-month follow-up data (data cut-off July 24, 2023). Compared to pre-treatment history, patients demonstrated substantial reductions in significant infections requiring hospitalization or intravenous antimicrobials, along with evidence of resolution of LAD-I-related skin and periodontal lesions and restoration of wound healing capabilities. RP-L201 remained well tolerated, with no new safety events related to the treatment. We continued to observe 100% survival without the need for allogeneic transplant, with all patients enrolled at less than 12 months of age surpassing 24 months without transplant. The clinical outcomes data from the nine severe LAD-I patients treated with KRESLADI™ was published in the New England Journal of Medicine (NEJM) in May 2025.

In September 2023, A BLA filing for RP-L201 was accepted by the FDA with priority review with an initial PDUFA date of March 31, 2024. In February 2024, the review time was extended by three months, to June 30, 2024, to allow additional time to review clarifying CMC information submitted by us in response to FDA information requests. In June 2024, we announced that the FDA issued a CRL in response to the BLA wherein the FDA requested limited additional CMC information to complete its review. Submission of a complete BLA to resolve CRL is anticipated in 2025.

Fanconi Anemia

Fanconi Anemia (FA), a rare and life-threatening DNA-repair disorder, characterized by bone marrow failure, cancer predisposition, and congenital malformations. Patients with FA have a genetic defect that prevents the normal repair of genes and chromosomes within blood cells in the bone marrow. An estimated 60% to 70% of cases arise from mutations in the FANCA gene. FA frequently results in bone marrow failure, developmental abnormalities, acute myeloid leukemia, and other myelodysplastic syndrome types of blood cancers, often during the early years and decades of life. Bone marrow aplasia, which is bone marrow that no longer produces any or very few red and white blood cells and platelets leading to infections and bleeding, is the most frequent cause of early morbidity and mortality in FA, with a median onset before 10 years of age. Leukemia is the next most common cause of mortality, ultimately occurring in about 20% of patients later in life. Solid organ malignancies, such as head and neck cancers, can also occur, although at lower rates during the first two to three decades of life. The average lifespan of an FA patient is estimated to be 30 to 40 years. The prevalence of FA in the U.S. and EU is estimated to be approximately 5,500 to 7,000 patients.

Although improvements in allogeneic (donor-mediated) HSCT, currently the most frequently utilized therapy for FA, have resulted in frequent hematologic correction of the disorder, HSCT is associated with both acute and long-term risks, including transplant-related mortality, graft failure, and graft versus host disease, a sometimes fatal side effect of allogeneic transplant characterized by painful ulcers in the GI tract, liver toxicity and skin rashes, as well as increased risk of subsequent cancers. Our gene therapy program in FA is designed to enable a minimally toxic hematologic correction using a patient’s own stem cells early in the disease course and administered without conditioning. We believe that the development of a broadly applicable autologous gene therapy can be transformative for these patients. In light of the efficacy seen in non-conditioned patients, the addressable annual market opportunity is now believed to be 400 to 500 patients collectively in the U.S. and EU.

RP-L102 is our investigational LV vector-based gene therapy for the treatment of FA. RP-L102’s lentiviral vector carries the FANCA gene as part of the PGK-FANCA-WPRE expression cassette which includes a phosphoglycerate kinase (PKG) promoter and an optimized woodchuck hepatitis virus post transcriptional regulatory element (WPRE). The Phase 2 study of RP-L102 for the treatment of FA type A without the use of myeloablative conditioning treated a total of 14 patients from the U.S. and EU. Patients received a single intravenous infusion of RP-L102 that utilizes fresh cells and an improved process which incorporates a modified stem cell enrichment process, transduction enhancers, as well as commercial-grade vector and final drug product. Rocket holds FDA RMAT, Rare Pediatric, and Fast Track designations in the U.S., PRIME and ATMP designations in the EU, and Orphan Drug designations in both regions for the program.

Resistance to mitomycin-C, a DNA damaging agent, in bone marrow stem cells at a minimum time point of one year post treatment is the primary endpoint for the Phase 2 study. Per agreement with the FDA and EMA, engraftment leading to bone marrow restoration exceeding a 10% mitomycin-C resistance threshold could support a marketing application for approval.

In May 2023, we presented updated clinical data for RP-L102 at the ASGCT 26th Annual Meeting. As of the data cut-off (April 17, 2023), RP-L102 conferred sustained genetic correction in 8 of 12 evaluable patients and comprehensive phenotypic correction in 7 of 12 evaluable patients with ≥12 months of follow-up as demonstrated by increased resistance to mitomycin-C in bone marrow-derived colony forming cells and hematologic stabilization. The safety profile of RP-L102 has been highly favorable, and the treatment, administered without any cytotoxic conditioning, has been well tolerated. No signs of bone marrow dysplasia, clonal dominance or insertional mutagenesis related to RP-L102 have been observed. Polyclonal integration patterns have been observed in each of the seven patients with phenotypic, genetic, and hematologic evidence of engraftment.

In May 2024, we provided an incremental clinical update at the ASGCT 27th Annual Meeting (data cut-off September 11, 2023). RP-L102 continued to demonstrate sustained genetic correction, phenotypic correction, and hematologic stability in 8 of 12 patients with greater than 12 months of follow-up. RP-L102 continued to be well tolerated with no significant safety signals.

On April 2, 2024, we announced that the EMA accepted our MAA for RP-L102. Submission of a BLA on a rolling review basis was initiated on September 26, 2024. As of July 2025, the Company is no longer allocating additional internal resources towards regulatory filings and commercial activities for RP-L102, including the MAA application, and we are actively exploring external partnership options to provide a path forward for RP-L102 and the FA community. This decision was based solely on business and strategic considerations and does not reflect any concerns regarding the safety, efficacy, or quality of the therapy.

Pyruvate Kinase Deficiency

Pyruvate Kinase Deficiency (PKD) is a rare, autosomal recessive, 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 potentially life-threatening anemia with a significant impact on quality of life. PKD has an estimated prevalence of 4,000 to 8,000 patients in the U.S. and Europe. Children are the most commonly and severely affected subgroup of patients. Patients with PKD have a high unmet medical need, as currently available treatments include splenectomy and red blood cell transfusions, which are associated with immune defects and chronic iron overload. Mitapivat, an oral enzyme activator, is approved for use in adult patients, however its efficacy is limited in more severely-afflicted patients, most notably in those who are splenectomized, transfusion-dependent, or whose disease results from deleterious mutations.

RP-L301 is our investigational gene therapy that contains autologous hematopoietic stem cells that have been genetically modified with a lentiviral vector to contain a functional copy of the PKLR gene for the treatment of PKD. Rocket holds FDA RMAT and Fast Track designations in the U.S., EMA PRIME designation in the EU, and Orphan Drug designation in both regions for the program. RP-L301 was in-licensed from the CIEMAT, Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER) and Instituto de Investigación Sanitaria de la Fundación Jiménez Díaz (IIS-FJD).

A global Phase 1 open-label, single-arm, clinical study with 2 adult patients and 2 pediatric patients (age 8-17) in the U.S. and Europe assessed the safety, tolerability, and preliminary activity of RP-L301. Stanford served as the lead site in the U.S. for adult and pediatric patients, HNJ served as the lead site in Europe for pediatrics, and Hospital Universitario Fundación Jiménez Díaz served as the lead site in Europe for adult patients.

In May 2023, we presented positive updated clinical data at the ASGCT 26th Annual Meeting (data cut-off May 3, 2023), which included up to 30 months of follow-up from the two treated adult patients and early clinical data from the first pediatric patient treated with RP-L301. Robust and sustained efficacy was observed in both adult patients at up to 30 months post-infusion evidenced by normalized hemoglobin (from baseline pre-treatment levels in the 7.0-7.5 g/dL range), improved hemolysis parameters, and red blood cell transfusion independence. Furthermore, both adult patients reported improved quality of life with documented improvements via formal quality of life assessments. The safety profile continues to appear highly favorable, with no RP-L301-related serious adverse events in either of the adult patients. Insertion site analyses in peripheral blood and bone marrow in both adult patients through 24 months post-RP-L301 demonstrated highly polyclonal patterns and there has been no evidence of insertional mutagenesis. The first pediatric patient infusion of RP-L301 was well tolerated, with engraftment achieved at day +15, hospital discharge less than one month following infusion, no RP-L301 related serious adverse events and early signs of efficacy. There were no red blood cell transfusion requirements following engraftment.

In February 2024, we presented further clinical updates at the ASGCT 27th Annual Meeting (data cut-off February 5, 2024), which included 36 months of follow-up on the two adult patients and 12 months of follow-up on the two pediatric patients. Sustained and clinically meaningful hemoglobin improvement was observed in all patients including hemoglobin normalization in three of four patients. No patients have required red blood cell transfusion following neutrophil engraftment. Improvements in hemoglobin supported by improved markers of hemolysis and quality of life have been observed. RP-L301 remains well-tolerated, with no drug-related serious adverse events. Insertion site analyses in the peripheral blood and bone marrow for both adult patients through 36 months post-RP-L301 continued to demonstrate highly polyclonal patterns with no clonal dominance or insertional mutagenesis.

Based on positive safety and efficacy data from the Phase 1 study, we have aligned with the FDA on the pivotal study design to support accelerated approval with a 10-patient, single-arm Phase 2 pivotal trial with a primary endpoint of ≥1.5 point Hgb improvement at 12 months. However, the Company is no longer allocating internal resources towards RP-L301 and does not plan to initiate enrollment in the Phase 2 RP-L301 study at this time. Like our FA program, we are actively exploring external partnership options to provide a path forward for RP-L301 and the PKD community.

Future Opportunities

In addition to the programs specified in this Quarterly Report, we are also conducting exploratory preclinical research and development. Research focus areas include the development of new candidates following our strategy outlined in “Our Strategy” section..

cGMP Manufacturing

We have a 103,720 square foot manufacturing facility located in Cranbury, New Jersey. This facility supports clinical development of our pipeline of LV and AAV gene therapies from discovery through pivotal trials, with space for potential future expansion and commercialization.

Financial Overview

Since our inception, we have devoted substantially all of our resources to organizing and staffing the Company, business planning, raising capital, acquiring or discovering product candidates and securing related intellectual property rights, conducting discovery, R&D activities for our product candidates and planning for potential commercialization. We do not have any products approved for sale and have not generated any revenue from product sales. From inception through June 30, 2025, we raised net cash proceeds of approximately $1.2 billion from investors through both equity and convertible debt financing to fund operating activities.

Revenue

To date, we have not generated any revenue from any sources, including from product sales, and we do not expect to generate any revenue from the sale of products in the near future. If our development efforts for product candidates are successful and result in regulatory approval or license agreements with third parties, we may generate revenue in the future from product sales.

Research and Development Expenses

Our R&D program expenses consist of both internal and external costs incurred for the development of our product candidates. These expenses include:

• expenses incurred under agreements with research institutions and consultants that conduct R&D activities including process development, preclinical, and clinical activities on our behalf;
• costs related to process development, production of preclinical and clinical materials, including fees paid to contract manufacturers, and manufacturing input costs for use in internal manufacturing processes;
• consultants supporting process development and regulatory activities; and
• costs related to in-licensing of rights to develop and commercialize our product candidate portfolio.

We recognize external development costs based on contractual payment schedules aligned with program activities, invoices for work incurred, and milestones that correspond with costs incurred by the third parties. Nonrefundable advance payments for goods or services to be received in the future for use in R&D activities are recorded as prepaid expenses.

Our direct R&D expenses are tracked on a program-by-program basis for product candidates and consist primarily of external costs, such as research collaborations and third-party manufacturing agreements associated with our preclinical research, process development, manufacturing, and clinical development activities. Our direct R&D expenses by program also include fees incurred under license agreements. Our personnel, non-program and unallocated program expenses include costs associated with activities performed by our internal R&D organization and generally benefit multiple programs. These costs are not separately allocated by product candidate and consist primarily of:

• salaries and personnel-related costs, including benefits, travel, and stock-based compensation, for our scientific personnel performing R&D activities;
• facilities and other expenses, which include expenses for rent and maintenance of facilities, depreciation expense, and laboratory supplies and equipment used for internal R&D activities.

We allocate salary and benefit costs directly related to specific programs. We do not allocate personnel-related discretionary bonus or stock-based compensation costs, costs associated with our general discovery platform improvements, depreciation or other indirect costs that are deployed across multiple projects under development and, as such, the costs are separately classified as other R&D expenses.

The following table presents R&D expenses tracked on a program-by-program basis as well as by type and nature of expense for the three and six months ended June 30, 2025, and 2024:

We cannot determine with certainty the duration and costs to complete current or future clinical studies of product candidates or if, when, or to what extent we will generate revenues from the commercialization and sale of any of our product candidates that obtain regulatory approval. We may never succeed in achieving regulatory approval for any of our product candidates. The duration, costs, and timing of clinical studies and development of product candidates will depend on a variety of factors, including:

• the scope, rate of progress, and expense of ongoing clinical studies as well as any clinical studies and other R&D activities that we undertake in the future;
• future clinical study results;
• uncertainties in clinical study enrollment rates;
• changing standards for regulatory approval; and
• the timing and receipt of any regulatory approvals.

We expect R&D expenses to remain significant for the foreseeable future as we continue to invest in R&D activities related to developing product candidates, including investments in manufacturing, as our programs advance into later stages of development and as we conduct additional clinical trials. The process of conducting the necessary clinical research to obtain regulatory approval is costly and time-consuming, and the successful development of product candidates is highly uncertain. As a result, we are unable to determine the duration and completion costs of R&D projects or when and to what extent we will generate revenue from the commercialization and sale of any of our product candidates.

Our future R&D expenses will depend on the clinical success of our product candidates, as well as ongoing assessments of the commercial potential of such product candidates. In addition, we cannot forecast with any degree of certainty which product candidates may be subject to future collaborations, when such arrangements will be secured, if at all, and to what degree such arrangements would affect our development plans and capital requirements. We expect our R&D expenses to increase in the foreseeable future as we seek further development of our product candidates.

The successful development and commercialization of our product candidates is highly uncertain. This is due to the numerous risks and uncertainties associated with product development and commercialization, including the uncertainty of:

• the scope, progress, outcome and costs of our clinical trials and other R&D activities;
• the efficacy and potential advantages of our product candidates compared to alternative treatments, including any standard of care;
• the market acceptance of our product candidates;
• obtaining, maintaining, defending, and enforcing patent claims and other intellectual property rights;
• significant and changing government regulation; and
• the timing, receipt, and terms of any marketing approvals.

A change in the outcome of any of these variables with respect to the development of our product candidates that we may develop could mean a significant change in the costs and timing associated with the development of our product candidates. For example, if the FDA or another regulatory authority were to require us to conduct clinical trials or other testing beyond those that we currently contemplate for the completion of clinical development of any of our product candidates that we may develop or if we experience significant delays in enrollment in any of our clinical trials, we could be required to expend significant additional financial resources and time on the completion of clinical development of that product candidate.

General and Administrative Expenses

General and administrative expenses consist primarily of salaries and related benefit costs for personnel, including stock-based compensation and travel expenses for our employees in commercial, executive, operational, finance, legal, business development, and human resource functions. In addition, other significant general and administrative expenses include professional fees for legal, consulting, investor and public relations, auditing, and tax services as well as other expenses for rent and maintenance of facilities, insurance and other supplies used in general and administrative activities. We expect general and administrative expenses to remain significant for the foreseeable future due to the significant headcount to support the continued advancement of our product candidates and our progression to commercial operations. We also anticipate that as we continue to operate as a public company with increasing complexity, we will continue to incur significant accounting, audit, legal, regulatory, compliance and director and officer insurance costs as well as investor and public relations expenses.

Restructuring Expense

In June 2025, the Company’s Board of Directors approved a restructuring plan to reduce the Company’s workforce and incurred aggregate charges of approximately $3.5 million in restructuring expenses, consisting of employee severance payments and other termination benefits.

Interest Expense

Interest expense for the three and six months ended June 30, 2025, and 2024 was related to our financing lease obligation for our Cranbury, NJ facility.

Interest and Other Income

Interest and other income for the six months ended June 30, 2025, was related to interest earned from investments and cash equivalents. Interest and other income for the six months ended June 30, 2024, was related to interest earned from investments and cash equivalents and reduced fair value of warrant liability.

Critical Accounting Policies and Significant Judgments and Estimates

There have been no material changes in our critical accounting policies and estimates in the preparation of our consolidated financial statements during the six months ended June 30, 2025, compared to those disclosed in our 2024 Form 10-K.

Results of Operations

Comparison of the Three Months Ended June 30, 2025 and 2024

The following table summarizes our results of operations, in thousands, for each of the periods presented:

Research and Development Expenses

R&D expenses decreased $3.7 million to $42.7 million for the three months ended June 30, 2025, compared to the three months ended June 30, 2024. The decrease in R&D expenses was primarily driven by decreases in manufacturing and development and direct costs of $2.3 million, professional fees of $2.0 million, and building supplies and consumables of $0.8 million. Decreases were partially offset by increases in clinical trial expenses of $1.2 million.

General and Administrative Expenses

G&A expenses decreased $2.3 million to $25.0 million for the three months ended June 30, 2025, compared to the three months ended June 30, 2024. The decrease in G&A expenses was primarily driven by decreases in commercial preparation related expenses of $1.4 million and compensation and benefit expenses of $0.9 million.

Restructuring Expense

In June 2025, the Company’s Board of Directors approved a restructuring plan to reduce the Company’s workforce and incurred aggregate charges of approximately $3.5 million in restructuring expenses, consisting of employee severance payments and other termination benefits.

Other Income, Net

Other income decreased $1.8 million to $2.2 million for the three months ended June 30, 2025, compared to the three months ended June 30, 2024. The decrease in other income was primarily driven by a decrease in interest and other income, net, of $1.8 million due to a decrease in interest earned on investments due to lower interest rates year over year and a decrease in fair value of warrant liabilities in 2024.

Comparison of the Six Months Ended June 30, 2025 and 2024

The following table summarizes our results of operations, in thousands, for each of the periods presented:

Research and Development Expenses

R&D expenses decreased $13.0 million to $78.6 million for the six months ended June 30, 2025, compared to the six months ended June 30, 2024. The decrease in R&D expenses was primarily driven by decreases in manufacturing and development and direct costs of $4.8 million, professional fees of $3.6 million, lab supplies and office expense of $2.2 million, and compensation and benefits expense of $1.3 million due to decreased R&D headcount. Reflected in the decrease in R&D expenses was the receipt of $2.7 million of CIRM grant recorded as a reduction of R&D expenses.

General and Administrative Expenses

G&A expenses increased $4.0 million to $53.5 million for the six months ended June 30, 2025, compared to the six months ended June 30, 2024. The increase in G&A expenses was primarily driven by increases in legal expenses of $4.3 million.

Restructuring Expense

In June 2025, the Company’s Board of Directors approved a restructuring plan to reduce the Company’s workforce and incurred aggregate charges of $3.5 million in restructuring expenses, consisting of employee severance payments and other termination benefits.

Other Income, Net

Other income decreased $4.1 million to $5.3 million for the six months ended June 30, 2025, compared to the six months ended June 30, 2024. The decrease in other income was primarily driven by a decrease in interest and other income, net, of $3.5 million due to a decrease in interest earned on investments due to lower interest rates year over year and a decrease in fair value of warrant liabilities in 2024 and a decrease in accretion of discount on investments, net, of $0.6 million.

Liquidity and Capital Resources

We have not generated any revenue and have incurred losses since inception. Operations of the Company are subject to certain risks and uncertainties, including, among others, those related to drug candidate development, technology and data security, patents and proprietary rights, our lack of commercial manufacturing marketing or sales experience, dependency on key personnel, compliance with government regulations and the need to obtain additional financing. Drug candidates currently under development will require significant additional R&D efforts, including extensive preclinical and clinical testing and regulatory approval, prior to commercialization. These efforts require significant amounts of additional capital, adequate personnel infrastructure, and extensive compliance-reporting capabilities.

Our drug candidates are in the development and clinical stage. There can be no assurance that our R&D will be successfully completed, that adequate protection for our intellectual property will be obtained, that any products developed will obtain necessary government approval or that any approved products will be commercially viable. Even if our product development efforts are successful, it is uncertain when, if ever, we will generate significant revenue from product sales. We operate in an environment of rapid change in technology and substantial competition from pharmaceutical and biotechnology companies.

Our consolidated financial statements have been prepared on the basis of continuity of operations, realization of assets and the satisfaction of liabilities in the ordinary course of business. Rocket has incurred net losses and negative cash flows from its operations each year since inception. We incurred net losses of $130.3 million for the six months ended June 30, 2025, and $258.7 million for the year ended December 31, 2024. We have experienced negative cash flows from operations and as of June 30, 2025, and December 31, 2024, we had an accumulated deficit of $1.35 billion and $1.22 billion, respectively. As of June 30, 2025, we had $271.5 million of cash, cash equivalents and investments. We believe that in accordance with the current operating plan, which reflects a strategic corporate reorganization announced in July 2025, such resources will be sufficient to fund our operating expenses and capital expenditure requirements into the second quarter of 2027. We have financed our operations primarily through proceeds from the sale of equity securities and continue to manage our capital resources with discipline and a focus on long-term sustainability.

In the longer term, our future viability is dependent on our ability to generate cash from operating activities or to raise additional capital to finance our operations. If we raise additional funds by issuing equity securities, our stockholders will experience dilution. Any future debt financing into which we enter may impose upon us additional covenants that restrict our operations, including limitations on our ability to incur liens or additional debt, pay dividends, repurchase our common stock, make certain investments and engage in certain merger, consolidation, or asset sale transactions. Any debt financing or additional equity that we raise may contain terms that are not favorable to us or our stockholders. Our failure to raise capital as and when needed could have a negative impact on our financial condition and ability to pursue our business strategies.

Cash Flows

The following table summarizes our cash flows from operating, investing and financing activities, in thousands, for each of the periods presented:

Operating Activities

During the six months ended June 30, 2025, operating activities used $104.8 million of cash and cash equivalents, primarily resulting from our net loss of $130.3 million offset by net non-cash charges of $22.5 million, including non-cash stock-based compensation expense of $21.2 million, depreciation and amortization expense of $5.6 million, partially offset by accretion of discount on investments of $4.3 million. Changes in our operating assets and liabilities for the six months ended June 30, 2025, included a decrease in accounts payable and accrued expenses of $2.9 million and an increase in our prepaid expenses of $0.2 million.

During the six months ended June 30, 2024, operating activities used $110.7 million of cash and cash equivalents, primarily resulting from our net loss of $131.7 million offset by net non-cash charges of $19.4 million, including non-cash stock-based compensation expense of $21.6 million, depreciation and amortization expense of $4.6 million, partially offset by accretion of discount on investments of $5.0 million and reduction in fair value of warrant liabilities of $1.8 million. Changes in our operating assets and liabilities for the six months ended June 30, 2024, included a decrease in accounts payable and accrued expenses of $2.1 million, and increase in our prepaid expenses of $0.7 million.

Investing Activities

During the six months ended June 30, 2025, net cash used by investing activities was $26.3 million, primarily resulting from proceeds of $166.8 million from the maturities of investments, offset by purchases of investments of $192.6 million, and purchases of property and equipment of $0.4 million.

During the six months ended June 30, 2024, net cash provided by investing activities was $90.7 million, primarily resulting from proceeds of $197.1 million from the maturities of investments, offset by purchases of investments of $102.5 million, and purchases of property and equipment of $4.0 million.

Financing Activities

During the six months ended June 30, 2025, financing activities provided $0.2 million of cash, consisting of return of short-swing profits.

During the six months ended June 30, 2024, financing activities provided $2.7 million of cash, consisting of proceeds from the exercise of stock options.

Contractual Obligations and Commitments

Information regarding contractual obligations and commitments may be found in Note 13 of our unaudited interim consolidated financial statements in this Quarterly Report on Form 10-Q. We do not have any off-balance sheet arrangements that are material or reasonably likely to become material to our financial condition or results of operations.

Recently Issued Accounting Pronouncements

There were no recent accounting pronouncements that impacted the Company, or which had a significant effect on the consolidated financial statements.

We are exposed to market risk related to changes in interest rates. As of June 30, 2025, and December 31, 2024, we had cash, cash equivalents and investments of $271.5 million and $372.3 million, respectively. The Company’s investments are primarily in U.S. Treasury Securities. Our primary exposure to market risk is interest rate sensitivity, which is affected by changes in U.S. interest rates and our investments that can decline in value if market interest rates increase. We do not utilize interest rate hedging agreements or other interest rate derivative instruments.

If market interest rates were to increase immediately and uniformly by 100 basis points, or one percentage point, from levels at June 30, 2025, the net effect on the net fair value of our investments would have resulted in a hypothetical decline of $0.7 million. While we believe our cash, cash equivalents, and marketable securities do not contain excessive risk, we cannot provide absolute assurance that, in the future, our investments will not be subject to adverse changes in market value.

Evaluation of Disclosure Controls and Procedures

Our management, with the participation of our principal executive and our principal financial officer, evaluated, as of the end of the period covered by this Quarterly Report on Form 10-Q, the effectiveness of our disclosure controls and procedures. Based on that evaluation of our disclosure controls and procedures as of June 30, 2025, our principal executive officer and principal financial officer concluded that our disclosure controls and procedures as of such date were effective at the reasonable assurance level. The term “disclosure controls and procedures,” as defined in Rules 13a-15(f) and 15d-15(f) under the Exchange Act, means controls and other procedures of a company that are designed to ensure that information required to be disclosed by a company in the reports that it files or submits under the Exchange Act are recorded, processed, summarized, and reported within the time periods specified in the SEC’s rules and forms.

Disclosure controls and procedures include, without limitation, controls and procedures designed to ensure that information required to be disclosed by us in the reports we file or submit under the Exchange Act is accumulated and communicated to our management, including our principal executive officer and principal financial officer, as appropriate to allow timely decisions regarding required disclosure. Management recognizes that any controls and procedures, no matter how well designed and operated, can provide only reasonable assurance of achieving their objectives and our management necessarily applies its judgment in evaluating the cost-benefit relationship of possible controls and procedures.

Inherent Limitations of Internal Controls

Because of its inherent limitations, internal control over financial reporting may not prevent or detect misstatements. Therefore, even those systems determined to be effective can provide only reasonable assurance with respect to financial statement preparation and presentation. Projections of any evaluation of effectiveness to future periods are subject to the risk that controls may become inadequate because of changes in conditions or that the degree of compliance with the policies or procedures may deteriorate.

Changes in Internal Control over Financial Reporting

There were no changes in our internal control over financial reporting during the period covered by this report that have materially affected, or are reasonably likely to materially affect, our internal control over financial reporting.

Our material risk factors are disclosed in Item 1A of our 2024 Form 10-K. Other than the below, there have been no material changes from the risk factors previously disclosed in such filing.

We are and may continue to be targets of securities-related class action and derivative lawsuits and defending against these claims could result in substantial costs and divert management time and resources and have a material adverse effect on our results of operations. These lawsuits, and any other lawsuits to which we are subject, may be costly to defend or pursue and are uncertain in their outcome

On June 11, 2025 and July 18, 2025, two stockholders filed putative securities class action lawsuits against us and certain of our executive officers in the United States District Court for the District of New Jersey, purportedly on behalf of classes of the Company’s investors who purchased or otherwise acquired the Company’s common stock between February 27, 2025 and May 26, 2025 and between September 17, 2024 and May 26, 2025, respectively. The complaints allege violations of Sections 10(b) and 20(a) of the Securities Exchange Act of 1934 and Rule 10b-5 promulgated thereunder in connection with various public statements made by the Company regarding its Phase 2 clinical trial for RP-A501 for Danon disease.

The outcome of litigation is necessarily uncertain, and we cannot predict the outcome of these pending legal proceedings. An unfavorable outcome in any such proceeding could have an adverse impact on our business, financial condition, results of operations and cash resources. In addition, we may be exposed to additional litigation even if no wrongdoing occurred and we ultimately prevail. Continuing or additional litigation, or responding to any related investigation or enforcement action, as well as a material final judgment or decree against us, would be expensive, divert management’s attention and resources, and could adversely affect our business, financial condition, results of operations and cash resources. Moreover, if our stock price is volatile, we could face additional securities class action lawsuits in the future.

Our strategic restructuring may not result in the savings we anticipate, could result in total costs and expenses that are greater than expected and could disrupt our operations

On July 23, the Company began implementation of a strategic corporate reorganization and pipeline prioritization aimed at maximizing near-term value, extending operational runway into the second quarter of 2027, and positioning the company for sustained long-term growth. As part of the restructuring, the Company implemented a reduction in workforce of approximately 30% (the “RIF”), which, along with other planned cost-saving initiatives, is expected to reduce the Company’s 12-month operating expenses by nearly 25%.

We may not realize, in full or in part, the anticipated benefits, savings and improvements from our restructuring and RIF due to unforeseen difficulties, delays or unexpected costs. If we are unable to realize the expected operational efficiencies and cost savings from our restructuring, our operating results and financial condition would be adversely affected. We also cannot guarantee that we will not have to undertake additional workforce reductions or restructuring activities in the future. In addition, the RIF could yield unanticipated consequences, such as attrition beyond planned staff reductions, or disruptions in our day-to-day operations. The RIF could also harm our ability to attract and retain qualified management, scientific, clinical, manufacturing and sales and marketing personnel who are critical to our business. Any failure to attract or retain qualified personnel could prevent us from successfully developing and commercializing, if approved, our product candidates,