Passage Bio's Shares Surge 25.74% Amid Positive Phase 1/2 upliFT-D Data

Introduction

Passage Bio Inc. (NASDAQ: PASG) is a Philadelphia-based clinical-stage genetic medicines company focused on developing one-time gene therapies for rare central nervous system (CNS) diseases. Its pipeline includes both pediatric and adult indications, specifically GM1 gangliosidosis and frontotemporal dementia (FTD) associated with GRN mutations.

Corporate Structure and Workforce

Founded in 2017, Passage Bio employs between 51 and 200 professionals across research and development, clinical operations, manufacturing, and corporate support functions. The organization is structured to progress its gene therapy candidates from preclinical research through regulatory milestones and commercialization planning.

Gene therapy by Sangharsh Lohakare

Recent Developments and News

On July 14, 2025, Passage Bio filed a Form 8-K reporting amendments to its articles of incorporation (Item 5.03), a material modification to security-holder rights (Item 3.03), other corporate events (Item 8.01), and related exhibits (Item 9.01). Specific details of these amendments have not been disclosed.

During the Alzheimer’s Association International Conference (AAIC) in July 2025, the company presented interim data from its Phase 1/2 upliFT-D trial (PBFT02) in frontotemporal dementia with GRN mutations. The presentation provided updates on the program, discussed planned protocol amendments, and outlined anticipated milestones through late 2025.

On July 18, 2025, Passage Bio acknowledged the passing of its General Counsel, Chip Cale, through a LinkedIn post, recognizing his contributions to corporate governance and legal strategy.

Institutional interest is noted by recent Schedule 13D/A filings from OrbiMed Advisors LLC and OrbiMed Capital GP VII LLC. In Amendment No. 8 (July 21, 2025), they reported beneficial ownership of 243,878 shares (7.82%). A subsequent Amendment No. 9 (July 24, 2025) adjusted that figure to 132,473 shares (4.25%).

Financial and Strategic Analysis

As of July 25, 2025, PASG closed at $7.205 per share, marking a 25.74% increase on a trading volume of 171,932 shares. This increase followed the AAIC data release and corporate filings. OrbiMed’s reported stake indicates institutional interest in Passage Bio’s gene therapy platform. The company aims to utilize orphan drug designations and expedited regulatory pathways, while forthcoming clinical readouts are expected to be significant value drivers.

Market Position and Industry Context

Passage Bio competes with gene therapy firms such as Axovant, Prevail Therapeutics, and Lysogene in the CNS sector. Its focus on both pediatric and adult neurodegenerative indications aligns with broader industry efforts to address unmet needs in rare CNS disorders. The company’s success will rely on clinical outcomes, scalable manufacturing, and effective reimbursement strategies under orphan-drug exclusivity frameworks.

tl;dr

On July 25, 2025, PASG shares increased 25.74% to $7.205 following interim Phase 1/2 upliFT-D data presented at AAIC. A July 14 8-K detailed corporate charter amendments, while July 21 and July 24 Schedule 13D/A filings by OrbiMed indicated ownership between 4.25% and 7.82%. Key upcoming events include full Phase 1/2 readouts and potential regulatory submissions in late 2025.