Core Viewpoint - Sanofi's SAR446268 has received fast track designation from the FDA for treating non-congenital myotonic dystrophy type 1, highlighting the urgency and potential of this gene therapy in addressing an unmet medical need [1][7]. Group 1: Product Development - SAR446268 utilizes a vectorized RNA interference approach to silence DMPK expression, aiming to reduce toxic RNA foci and restore normal muscle function [2]. - The therapy is currently in a first-in-human phase 1-2 study to assess safety, tolerability, and efficacy, with patient enrollment expected to begin in late 2025 [3]. - Sanofi has received orphan designations for SAR446268 in both the US and EU, indicating its potential significance in treating rare diseases [3]. Group 2: Disease Overview - Myotonic dystrophy type 1 (DM1) is a rare genetic disorder affecting approximately 1 in 2,300 people globally, characterized by progressive muscle weakness and various systemic effects [4]. - The condition is caused by mutations in the DMPK gene and has no currently approved treatments, emphasizing the importance of SAR446268 [4][7]. Group 3: Company Profile - Sanofi is an R&D driven biopharma company focused on improving lives through innovative medicines and vaccines, with a commitment to addressing urgent healthcare challenges [5].

Summary of Passage Bio (PASG) FY Conference Call - September 05, 2025 Company Overview - Passage Bio is a clinical stage genetic medicines company focused on neurodegenerative diseases, particularly frontotemporal dementia (FTD) [2][3] Core Program: PBFT02 - PBFT02 is the lead clinical program targeting frontotemporal dementia with the GRN mutation, addressing a significant unmet need as there are no approved disease-modifying therapies for this condition [2][4] - The target population includes approximately 18,000 patients with GRN mutation FTD and 21,000 with C9orf72 mutation FTD across the U.S. and Europe [3] Clinical Development and Milestones - The ongoing phase 1/2 study of PBFT02 is a multicenter international open-label dose exploration study, currently active in the U.S., Canada, Portugal, and Brazil [7] - Key upcoming milestones include seeking regulatory feedback on manufacturing comparability in Q4 2025 and reporting dose two data in the first half of 2026 [3][21] Mechanism of Action - PBFT02 utilizes AAV gene therapy to increase levels of progranulin, a protein crucial for CNS cell homeostasis, which is deficient in patients with GRN mutation FTD [4][5] - The administration route is intracisterna magna, allowing for broad CNS biodistribution and lower doses compared to systemic delivery [9][10] Clinical Data and Safety Profile - Initial cohorts have shown promising results, with dose one achieving an average of over 25 nanograms per ml of progranulin levels at 12 months, indicating robust and durable responses [15][18] - The safety profile includes three serious adverse events (SAEs) among eight treated patients, with a decision to implement prophylactic anticoagulation for future patients due to observed venous thromboembolic events [12][20] Biomarker Analysis - Plasma neurofilament levels, a marker of neurodegeneration, showed a significant reduction in treated patients compared to the expected annual increase of 29% in untreated patients, suggesting a potential slowing of disease progression [17][20] - The study is also tracking CSF progranulin levels and clinical dementia rating scales to assess treatment efficacy [9][11] Competitive Landscape - PBFT02 is positioned as a potentially best-in-class therapy, with higher and more durable progranulin levels compared to other therapies in development for FTD [18][19] - Market research indicates a preference for a one-time therapy over monthly treatments, particularly for patients with behavioral dementia [19] Future Directions - Plans to expand the clinical study to include FTD C9 patients, as raising progranulin may also benefit TDP-43 pathology seen in multiple neurodegenerative diseases [20][21] - The company has a cash balance of $58 million, providing a runway into Q1 2027 to continue patient treatment and data collection [22] Conclusion - Passage Bio is advancing its clinical program for PBFT02 with promising early data and a clear regulatory pathway, aiming to address significant unmet needs in neurodegenerative diseases [22]

Core Insights - REGENXBIO Inc. announced preclinical results showing that a microdystrophin gene therapy construct with the C-terminal (CT) domain provides improved functional benefits for patients with Duchenne Muscular Dystrophy compared to a construct without the CT domain [1][4][5] - RGX-202 is the only investigational microdystrophin gene therapy candidate that includes the CT domain, making it closest to naturally occurring dystrophin [2][8] Group 1: Research Findings - The preclinical study published in Molecular Therapy Methods and Clinical Development demonstrated that the microdystrophin with the CT domain was maintained at higher levels in transduced muscles and effectively recruited the dystrophin-associated protein complex to the muscle membrane [4][5] - The incorporation of the CT domain enhances the microdystrophin design, allowing for higher accumulation levels in muscle and potentially improving functional benefits [5][7] Group 2: Clinical Trial Insights - Interim results from the Phase I/II AFFINITY DUCHENNE trial indicated that RGX-202 showed consistent evidence of positively changing the disease trajectory in patients with Duchenne and had a favorable safety profile [5][6] - REGENXBIO is currently enrolling participants in the pivotal portion of the Phase I/II/III AFFINITY DUCHENNE trial and plans to submit a Biologics License Application (BLA) via the accelerated approval pathway in mid-2026 [6][9] Group 3: Company Overview - REGENXBIO is a biotechnology company focused on gene therapy, with a late-stage pipeline that includes RGX-202 for Duchenne, among other treatments for rare diseases [11] - The company has pioneered AAV gene therapy since its founding in 2009 and has treated thousands of patients with its AAV platform [11]

PBFT02 Development and Preclinical Results - PBFT02 is an AAV gene therapy designed to deliver functional PGRN to the brain for the treatment of FTD-GRN [13] - In Grn-/- mice, AAV.hGRN vector ICV administration improved lysosomal function, reduced lipofuscin fluorescence in the thalamus, and reduced brain hexosaminidase activity [21, 23] - AAV1 was selected as the vector serotype due to superior hPGRN levels in CSF compared to AAV5 and AAVhu68 in NHPs [28, 29] - In Grn-/- mice, PBFT02 reduced lipofuscin deposition and neuroinflammation in the brain after intra-CSF delivery [34, 37] - ICM administration of PBFT02 enables PGRN delivery throughout the CNS [40] - In NHPs, PBFT02 dose-dependently increased PGRN in CSF up to day 14 [46, 48] - In NHPs, PBFT02 at Dose 1 resulted in approximately 10e4 GC/ug DNA throughout the brain [43] Clinical Trial (upliFT-D) and Safety - The upliFT-D trial is a global Phase 1/2 multi-center, open-label, dose-escalation study with PBFT02 [52, 55] - FTD-GRN Cohort 1 (n = 5) dosing is complete [56] - All four Cohort 1 participants who received a revised immunosuppression regimen had no SAEs or significant immune responses [57] - Cohort 1 interim data shows PBFT02 administration leads to robust and sustained increases in CSF PGRN [58]

Financial Data and Key Metrics Changes - REGENXBIO ended the quarter on March 31, 2025, with cash, cash equivalents, and marketable securities of $272 million, an increase from $245 million as of December 31, 2024, primarily driven by a $110 million upfront payment from the Nippon Shinyaku collaboration [24] - R&D expenses were $53 million for the quarter ended March 31, 2025, compared to $54.8 million for the same quarter in 2024, reflecting a decrease due to clinical trial expenses for RGX-314 and RGX-202 [25] Business Line Data and Key Metrics Changes - RGX-121, a potential first gene therapy for MPS II, is on track for potential FDA approval in the second half of 2025, with a BLA submitted under the accelerated approval pathway [8][9] - RGX-202, a next-generation candidate for Duchenne muscular dystrophy (DMD), has surpassed 50% enrollment in its pivotal study and is expected to submit a BLA in mid-2026 [10][11] - The retinal program, RGX-314, is advancing in two pivotal studies for wet AMD and is on track to be the first gene therapy on the market for this condition [12][19] Market Data and Key Metrics Changes - The DMD market is projected to have over half of the prevalent population untreated by 2027, highlighting a significant opportunity for RGX-202 [11] - The wet AMD and diabetic retinopathy markets represent large multibillion-dollar commercial opportunities, with RGX-314 positioned to serve as a meaningful alternative to current treatments [12][19] Company Strategy and Development Direction - The company is focused on transitioning to a commercial stage with in-house manufacturing capabilities and plans to secure non-dilutive funding [6][8] - A strategic partnership with Nippon Shinyaku aims to commercialize the neurodegenerative franchise, including RGX-121 and RGX-111 [9] - The company is preparing for commercial supply manufacturing of RGX-202 in anticipation of a 2027 launch [11][27] Management's Comments on Operating Environment and Future Outlook - Management expressed confidence in the imminent acceptance of the BLA for RGX-121 and the positive trajectory of clinical programs [34][51] - The company is optimistic about the evolving regulatory landscape and the potential for accelerated approval pathways, particularly in light of recent developments in the industry [36][44] Other Important Information - The company has a robust cash runway expected to fund operations into the second half of 2026, with potential extensions through non-dilutive financing options [25][26] - The manufacturing innovation center in Rockville, Maryland, is capable of producing up to 2,500 doses of RGX-202 annually, ensuring readiness for market needs [11][12] Q&A Session Summary Question: Timing for the Hunter BLA - Management indicated that the BLA acceptance is imminent and they feel confident about the review process [34] Question: Competitor Insights and Regulatory Expectations - Management discussed the evolving expectations for accelerated approval in DMD, emphasizing the strength of their safety and functional data [36][44] Question: Changes in FDA Requirements - Management noted that there are no anticipated changes in the accelerated approval pathway and enrollment is on track [43][44] Question: Planning for Diabetic Retinopathy Phase III Trial - Management confirmed ongoing interactions with the FDA and that they are on track for first patient dosing this year [55] Question: Updates on DMD Functional Data - Management plans to release additional functional data in the first half of the year, focusing on dose level two patients [62][88] Question: Impact of Recent Pricing Announcements - Management stated it is too early to assess the impact of recent pricing discussions on their gene therapies [104]