Passage Bio (PASG) Stock Price, News & Analysis

Passage Bio, Inc. (NASDAQ: PASG) is a clinical stage genetic medicines company focused on improving the lives of patients with neurodegenerative diseases. According to the company’s public disclosures, its primary focus is the development and advancement of one-time therapies designed to target the underlying pathology of these conditions. Passage Bio’s lead product candidate, PBFT02, is being developed to treat neurodegenerative conditions, including frontotemporal dementia, by elevating progranulin levels to restore lysosomal function and slow disease progression.

Core business focus

Passage Bio describes itself as a clinical stage genetic medicines company with a mission to improve outcomes for patients and families affected by neurodegenerative diseases. The company is advancing genetic medicines that are intended to address disease mechanisms rather than only symptoms. Its lead program, PBFT02, is central to this strategy and is being evaluated in frontotemporal dementia with granulin mutations (FTD-GRN) and frontotemporal dementia with C9orf72 mutations (FTD-C9orf72) in an ongoing clinical trial.

Lead program: PBFT02 and upliFT-D trial

PBFT02 is described as a gene replacement therapy that utilizes an AAV1 viral vector to deliver, through intra cisterna magna (ICM) administration, a functional GRN gene that encodes progranulin (PGRN). The goal of this construct and delivery approach is to elevate PGRN levels in the central nervous system to alter the course of neurodegenerative diseases. Interim clinical data from the Phase 1/2 upliFT-D study in FTD-GRN participants have shown robust elevations in PGRN levels in cerebrospinal fluid (CSF).

The upliFT-D trial (NCT04747431) is described as a Phase 1/2 global, multi-center, open-label clinical trial of PBFT02 administered by single injection into the cisterna magna in patients aged 35 to 75 years with FTD-GRN or FTD-C9orf72. The trial is designed to sequentially enroll three FTD-GRN cohorts and two FTD-C9orf72 cohorts. Enrollment is ongoing. The primary endpoint is to evaluate the safety and tolerability of PBFT02, and secondary endpoints include disease biomarkers and clinical outcome measures. The study is planned as a two-year clinical trial with a three-year safety extension.

Biomarker and safety observations reported

Passage Bio has reported interim biomarker data from FTD-GRN patients treated with PBFT02. Dose 1 PBFT02 treatment resulted in a robust and durable increase in CSF PGRN expression through 18 months post-treatment, with increases observed in all treated patients. For the first patient treated with Dose 2 PBFT02, which is 50% lower than Dose 1, CSF PGRN levels increased substantially at one month and approached the upper limit of a healthy adult reference range.

The company has also reported that patients who received Dose 1 PBFT02 experienced a reduced annual rate of change in plasma neurofilament light chain (NfL), a disease progression biomarker, compared to rates observed in natural history studies of untreated symptomatic FTD-GRN patients. Safety data disclosed include treatment-emergent adverse events, most of which were mild to moderate in severity, and several serious adverse events that were described in detail, including venous sinus thrombosis, hepatotoxicity, and pulmonary embolism in the context of a systemic infection.

Manufacturing approach

Passage Bio has described the development of a high-productivity, suspension-based manufacturing process for PBFT02 at 200-liter scale. According to the company, this suspension-based, GMP-ready process substantially improved productivity, capsid purity, and the percentage of full capsids compared to its adherent-based manufacturing process. The company has reported that a single batch of the suspension-based process is estimated to yield more than 1,000 doses of PBFT02 at a specified dose level, with high capsid purity and a high percentage of full capsids.

The company has engaged with the U.S. Food and Drug Administration (FDA) through a Type D Chemistry, Manufacturing, and Controls (CMC) meeting and has stated that it aligned with the FDA on key elements of an analytical plan to establish process comparability for the suspension-based PBFT02 manufacturing process. This comparability work is intended to support potential future use of the suspension-based process in later-stage studies.

Clinical development strategy

Passage Bio’s disclosures emphasize continued execution of the upliFT-D trial in both FTD-GRN and FTD-C9orf72 populations. The company has described multiple cohorts, including Dose 1 and Dose 2 in FTD-GRN, and plans to enroll additional cohorts in both genetic subtypes. Protocol amendments have been implemented or submitted to introduce a short course of low-dose prophylactic anticoagulation and to revise inclusion criteria to allow enrollment of patients who are prodromal or have mild cognitive impairment while excluding patients who are more severely progressed.

The company has publicly stated its intention to seek regulatory feedback on a potential registrational trial design for PBFT02 in FTD-GRN, including discussion of possible trial design elements. It has also indicated plans to obtain regulatory feedback on comparability of the suspension-based manufacturing process.

Support for trial enrollment

To support recruitment and enrollment in the upliFT-D trial, Passage Bio has described a collaborative partnership with InformedDNA. Through this collaboration, the company reports that no-cost genetic counseling and testing are provided for adults who have been diagnosed by their physicians with frontotemporal dementia. This initiative is intended to identify eligible patients and support participation in the clinical program.

Financial reporting and listing status

Passage Bio files periodic financial results and other updates with the U.S. Securities and Exchange Commission (SEC). The company has reported research and development expenses, general and administrative expenses, and net loss figures for recent quarters and years, as well as its cash, cash equivalents, and marketable securities balances. The company has also discussed its expected cash runway into a specified future period.

Passage Bio’s common stock trades on the Nasdaq Capital Market under the symbol PASG. In 2025, the company implemented a 1-for-20 reverse stock split of its common stock following stockholder approval and board action. The reverse stock split was intended to address Nasdaq’s minimum bid price requirement. Subsequent SEC filings report that Nasdaq staff confirmed the company had regained compliance with the minimum bid price rule, and that the listing matter was closed.

Corporate governance updates

In an 8-K filing, Passage Bio reported changes to its Board of Directors, including the resignation of a director and the appointment of another director to the Audit Committee. The company disclosed that the resignation was not the result of any disagreement with the company on matters relating to its operations, policies, or practices, and that the size of the Board was reduced in connection with this change.

Industry classification

Based on the provided classification, Passage Bio is associated with the Biological Product (except Diagnostic) Manufacturing industry within the broader Manufacturing sector. Its activities, as described in public materials, are centered on genetic medicines and gene therapy approaches for neurodegenerative diseases.