Form 8-K - Current report

0001787297false00017872972024-08-082024-08-08

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UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d)

of the Securities Exchange Act of 1934

Date of Report (Date of earliest event reported): August 8, 2024

PASSAGE BIO, INC.

(Exact name of registrant as specified in its charter)

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Delaware	001-39231	82-2729751
(State or other jurisdiction of incorporation)	(Commission File Number)	(IRS Employer Identification No.)

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One Commerce Square 2005 Market Street, 39th Floor Philadelphia, PA	19103
(Address of principal executive offices)	(Zip Code)

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[phone]

(Registrant’s telephone number, including area code)

N/A

(Former name or former address, if changed since last report)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

☐	Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

☐	Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

☐	Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

☐	Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act:

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Title of each class	Trading symbol(s)	Name of each exchange on which registered
Common Stock, $0.0001 Par Value Per Share	PASG	The Nasdaq Stock Market LLC (Nasdaq Global Select Market)

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Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

Emerging growth company ☒

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

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Item 2.02 Results of Operations and Financial Condition.

On August 8, 2024, Passage Bio, Inc. (the “Company”) issued a press release announcing its financial results for the quarter ended June 30, 2024. A copy of the press release is attached as Exhibit 99.1 to this report.

The information in this Item 2.02, including Exhibit 99.1 to this report, shall not be deemed to be “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or otherwise subject to the liabilities of that section or Sections 11 and 12(a)(2) of the Securities Act of 1933, as amended (the “Securities Act”). The information contained in this Item 2.02 and in the accompanying Exhibit 99.1 shall not be incorporated by reference into any other filing under the Exchange Act or under the Securities Act, except as shall be expressly set forth by specific reference in such filing.

Item 7.01 Regulation FD Disclosure.

On August 8, 2024, the Company updated its corporate presentation. A copy of the corporate presentation is attached as Exhibit 99.2 to this Current Report on Form 8-K.

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The information in this Item 7.01, including Exhibit 99.2 to this Current Report on Form 8-K, shall not be deemed to be “filed” for purposes of Section 18 of the Exchange Act, or otherwise subject to the liabilities of that section or Sections 11 and 12(a)(2) of the Securities Act. The information contained in this Item 7.01 and in the accompanying Exhibit 99.2 shall not be incorporated by reference into any other filing under the Exchange Act or under the Securities Act, except as shall be expressly set forth by specific reference in such filing.

Item 9.01 Financial Statements and Exhibits.

(d)Exhibits

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Exhibit No.	​	Description
99.1	​	Press release issued by Passage Bio, Inc. regarding its financial results for the quarter ended June 30, 2024, dated August 8, 2024.
99.2	​	Corporate Presentation.
104	​	Cover Page Interactive Data File (formatted as Inline XBRL).
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SIGNATURE

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

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​	PASSAGE BIO, INC.
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Date: August 8, 2024	By:	/s/ Kathleen Borthwick
​	​	Kathleen Borthwick
​	​	Chief Financial Officer

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‌Ex 99.1

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PASSAGE BIO REPORTS SECOND QUARTER 2024 FINANCIAL RESULTS AND PROVIDES RECENT BUSINESS HIGHLIGHTS

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Enrolled first FTD-GRN patient in Cohort 2 in upliFT-D trial

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Plan to present updated safety and biomarker data from Cohort 1 FTD-GRN patients treated with PBFT02 at 14th International Conference on Frontotemporal Dementias (ISFTD2024) in September 2024

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Achieved alignment with Food and Drug Administration (FDA) on the company's proposed clinical development plans to expand the upliFT-D trial to assess PBFT02 in FTD patients with C9orf72 gene mutations

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Completed out-licensing of pediatric lysosomal storage disease programs to GEMMA Biotherapeutics

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Strong balance sheet to support continued execution, with cash runway to fund operations extended to the end of Q2 2026

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PHILADELPHIA – August 8, 2024 – Passage Bio, Inc. (Nasdaq: PASG), a clinical stage genetic medicines company focused on improving the lives of patients with neurodegenerative diseases, today reported financial results for the second quarter ended June 30, 2024 and provided recent business highlights.

“This has been a pivotal quarter for our company, marked by significant momentum in our upliFT-D trial, increased clarity around our strategy to expand PBFT02 into additional adult neurodegenerative indications, and out-licensing of our pediatric lysosomal storage disorder programs,” said Will Chou, M.D., president and chief executive officer of Passage Bio. “The positive recommendation of the IDMC to proceed to Cohort 2 dosing in our upliFT-D trial for FTD-GRN reinforces the well-tolerated safety profile of PBFT02 when combined with our revised immunosuppression regimen, and we are excited to present updated safety and biomarker data from Cohort 1 at the ISFTD2024 conference in Amsterdam this September. We are also pleased the FDA is aligned with our proposed expansion of our upliFT-D trial to include FTD-C9orf72 patients and expect to initiate dosing of these patients in the first half of 2025. The company remains on track to gain regulatory feedback on the pathway to treating ALS patients with PBFT02 in the second half of 2024.”

Dr. Chou continued, "Furthermore, we completed the out-licensing of our pediatric lysosomal storage disease programs to GEMMA Biotherapeutics. Dr. Wilson and the entire GEMMABio team are committed to developing these promising therapies for pediatric patients with life-threatening conditions. We look forward to our continued research and collaboration efforts with their team, driving advancements and hope for those affected by neurodegenerative diseases.”

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‌Ex 99.1

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Recent Highlights

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Enrolled first patient in Cohort 2 in upliFT-D trial for FTD-GRN: Following IDMC review of all available Cohort 1 safety data, the first patient in Cohort 2 has been enrolled in the trial; Cohort 2 will consist of three to five FTD-GRN patients to be treated with Dose 1. Dose 1 of PBFT02 continues to be well-tolerated in Cohort 1 patients who received the revised immunosuppression protocol (n=4). Recruitment efforts for subsequent Cohort 2 patients are well underway across seven clinical trial sites in Brazil, Canada, the United States and Europe.

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Plan to present updated safety and biomarker data from Cohort 1 patients in upliFT-D trial at ISFTD2024: Juan Chavez, M.D., vice president of clinical development at Passage Bio, will deliver updated data from Cohort 1 during an oral presentation, Interim Safety and Biomarker Data From upliFT-D Trial of PBFT02 in FTD with GRN Mutations, on Friday, September 20, 2024 at the 14th International Conference on Frontotemporal Dementias (ISFTD2024).

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Received FDA agreement on the company’s proposed expansion of the ongoing upliFT-D trial to treat FTD-C9orf72 patients with PBFT02: Substantial preclinical evidence, coupled with available safety and robust progranulin (PGRN) expression data from the first cohort of FTD-GRN patients treated with PBFT02, supported FDA alignment on the proposed trial expansion. The company intends to amend the protocol for the ongoing upliFT-D study to introduce a new population of FTD-C9orf72 patients and expects to initiate dosing of FTD-C9orf72 patients in 1H 2025.

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Completed out-licensing of pediatric lysosomal storage disease programs to GEMMA Biotherapeutics: Under the terms of the transaction, the company will receive initial payments of $10 million for the purchase of clinical product supply and up to an additional $10 million contingent on completion of certain GEMMABio business milestones. The company is also eligible to receive up to an additional $114 million in development and commercial milestones, as well as future royalties. GEMMA Biotherapeutics, a newly formed company co-founded by James M. Wilson, M.D., Ph.D., received an exclusive, worldwide license to PBGM01 for the treatment of GM1 gangliosidosis, PBKR03 for the treatment of Krabbe disease, and PBML04 for the treatment of metachromatic leukodystrophy. GEMMA Biotherapeutics is responsible for all future development of, and any remaining financial obligations owed to the University of Pennsylvania for the licensed programs.

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Entered into research, collaboration, and license agreement with GEMMA Biotherapeutics: Following a restructuring of the company’s original agreement with the University of Pennsylvania’s Gene Therapy Program, a research, collaboration, and license agreement with GEMMA Biotherapeutics was finalized. The partnership will focus on continued execution of preclinical studies in Huntington's disease, and the company will retain rights to future options in the CNS field, ensuring continued strategic growth and innovation in these critical areas.

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‌Ex 99.1

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Anticipated Upcoming Milestones:

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FTD-GRN

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Report updated safety and biomarker data from Cohort 1 patients at ISFTD2024 in September 2024

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Report 12-month Cohort 1 and interim Cohort 2 data in 1H 2025

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Seek regulatory feedback on pivotal trial design in 2H 2025

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FTD-C9orf72 and ALS

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Obtain regulatory feedback on the pathway to treating amyotrophic lateral sclerosis (ALS) patients with PBFT02 in 2H 2024

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Initiate dosing of FTD-C9orf72 patients in 1H 2025

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Second Quarter 2024 Financial Results

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Cash Position: Cash, cash equivalents and marketable securities were $91.8 million as of June 30, 2024, as compared to $151.5 million as of June 30, 2023. The company expects current cash, cash equivalents and marketable securities, together with the initial payments from our out-licensing agreements with Gemma Biotherapeutics, to fund operations to the end of Q2 2026.

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Research and Development (R&D) Expenses: R&D expenses were $10.4 million for the quarter ended June 30, 2024, as compared to $17.3 million for the quarter ended June 30, 2023.

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General and Administrative (G&A) Expenses: G&A expenses were $6.5 million for the quarter ended June 30, 2024, as compared to $8.1 million for the quarter ended June 30, 2023.

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Net Loss: Net loss was $16.0 million, or $0.26 per basic and diluted share, for the quarter ended June 30, 2024, as compared to a net loss of $23.9 million, or $0.44 per basic and diluted share, for the quarter ended June 30, 2023.

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‌Ex 99.1

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About Passage Bio

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Passage Bio (Nasdaq: PASG) is a clinical stage genetic medicines company on a mission to improve the lives of patients with neurodegenerative diseases. Our primary focus is the development and advancement of cutting-edge, one-time therapies designed to target the underlying pathology of these conditions. Passage Bio’s lead product candidate, PBFT02, seeks to treat neurodegenerative conditions, including frontotemporal dementia, by elevating progranulin levels to restore lysosomal function and slow disease progression. 

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To learn more about Passage Bio and our steadfast commitment to protecting patients and families against loss in neurodegenerative conditions, please visit: www.passagebio.com.

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Forward-Looking Statements
This press release contains “forward-looking statements” within the meaning of, and made pursuant to the safe harbor provisions of, the Private Securities Litigation Reform Act of 1995, including, but not limited to: our expectations about timing and execution of anticipated milestones, including the initiation of dosing of FTD-C9orf72 patients, feedback from regulatory authorities, the progress of clinical studies and the availability of clinical data from such trials; our expectations about our collaborators’ and partners’ ability to execute key initiatives; our ability to receive milestone payments from our partners; our expectations about cash runway; and the ability of our product candidates to treat their respective target CNS disorders. These forward-looking statements may be accompanied by such words as “aim,” “anticipate,” “believe,” “could,” “estimate,” “expect,” “forecast,” “goal,” “intend,” “may,” “might,” “plan,” “potential,” “possible,” “will,” “would,” and other words and terms of similar meaning. These statements involve risks and uncertainties that could cause actual results to differ materially from those reflected in such statements, including: our ability to develop and obtain regulatory approval for our product candidates; the timing and results of preclinical studies and clinical trials; risks associated with clinical trials, including our ability to adequately manage clinical activities, unexpected concerns that may arise from additional data or analysis obtained during clinical trials, regulatory authorities may require additional information or further studies, or may fail to approve or may delay approval of our drug candidates; the occurrence of adverse safety events; the risk that positive results in a preclinical study or clinical trial may not be replicated in subsequent trials or success in early stage clinical trials may not be predictive of results in later stage clinical trials; failure to protect and enforce our intellectual property, and other proprietary rights; our dependence on collaborators and other third parties for the development and manufacture of product candidates and other aspects of our business, which are outside of our full control; risks associated with current and potential delays, work stoppages, or supply chain disruptions; and the other risks and uncertainties that are described in the Risk Factors section in documents the company files from time to time with the Securities and Exchange Commission (SEC), and other reports as filed with the SEC. Passage Bio undertakes no obligation to publicly update any forward-looking statement, whether written or oral, that may be made from time to time, whether as a result of new information, future developments or otherwise.

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‌Ex 99.1

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Passage Bio, Inc.

Balance Sheets

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​	​	(Unaudited)		​	​	​
(in thousands, except share and per share data)		June 30, 2024			December 31, 2023
Assets		​			​
Current assets:		​			​
Cash and cash equivalents	​	$	24,770	​	$	21,709
Marketable securities	​	​	67,003	​	​	92,585
Prepaid expenses and other current assets	​		1,397	​		923
Prepaid research and development	​		1,830	​		2,742
Total current assets	​		95,000	​		117,959
Property and equipment, net	​		13,054	​		15,295
Right of use assets - operating leases	​	​	16,822	​		16,858
Other assets	​		516	​		433
Total assets	​	$	125,392	​	$	150,545
Liabilities and stockholders’ equity	​		​	​
Current liabilities:	​		​	​
Accounts payable	​	$	621	​	$	1,298
Accrued expenses and other current liabilities	​		8,063	​		11,670
Operating lease liabilities	​	​	3,701	​		3,373
Total current liabilities	​		12,385	​		16,341
Operating lease liabilities - noncurrent	​		22,450	​		22,921
Total liabilities	​		34,835	​		39,262
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Stockholders’ equity:	​		​	​
Preferred stock, $0.0001 par value: 10,000,000 shares authorized; no shares issued and outstanding at both June 30, 2024 and December 31, 2023	​	​	—	​	​	—
Common stock, $0.0001 par value: 300,000,000 shares authorized; 61,754,786 shares issued and outstanding at June 30, 2024 and 54,944,130 shares issued and outstanding at December 31, 2023	​		6	​		5
Additional paid‑in capital	​		717,788	​		705,789
Accumulated other comprehensive income (loss)	​	​	(67)	​	​	(43)
Accumulated deficit	​		(627,170)	​		(594,468)
Total stockholders’ equity	​		90,557	​		111,283
Total liabilities and stockholders’ equity	​	$	125,392	​	$	150,545

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‌Ex 99.1

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Passage Bio, Inc.

Statements of Operations and Comprehensive Loss

(Unaudited)

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Three Months Ended June 30,

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Six Months Ended June 30,

(in thousands, except share and per share data)

2024

2023

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2024

2023

Operating expenses:

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Research and development

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$

10,430

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$

17,324

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$

21,965

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$

34,160

General and administrative

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6,510

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8,064

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13,025

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27,111

Impairment of long-lived assets

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438

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—

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438

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—

Loss from operations

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(17,378)

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(25,388)

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(35,428)

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(61,271)

Other income (expense), net

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1,387

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1,532

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2,726

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3,077

Net loss

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$

(15,991)

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$

(23,856)

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$

(32,702)

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$

(58,194)

Per share information:

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Net loss per share of common stock, basic and diluted

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$

(0.26)

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$

(0.44)

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$

(0.55)

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$

(1.06)

Weighted average common shares outstanding, basic and diluted

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61,682,475

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54,683,817

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58,989,007

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54,651,488

Comprehensive loss:

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​

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Net loss

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$

(15,991)

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$

(23,856)

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$

(32,702)

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$

(58,194)

Unrealized gain (loss) on marketable securities

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2

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87

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(24)

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626

Comprehensive loss

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$

(15,989)

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$

(23,769)

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$

(32,726)

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$

(57,568)

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For further information, please contact:

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Investors:

Stuart Henderson

Passage Bio

267.866.0114

[e-mail]

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Media:

Mike Beyer
Sam Brown Inc. Healthcare Communications
312.961.2502
[e-mail] 

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Exhibit 99.2

Nasdaq: PASG © 2024 Passage Bio. All rights reserved. Corporate Presentation August 2024

2 Forward-Looking Statement This presentation includes “forward-looking statements” within the meaning of, and made pursuant to the safe harbor provisions of, the Private Securities Litigation Reform Act of 1995, including, but not limited to: our expectations about timing and execution of anticipated milestones, including the initiation of dosing of FTD-C9orf72 patients, feedback from regulatory of authorities, the progress of clinical studies and the availability of clinical data from such trials; our expectations about our collaborators’ and partners’ ability to execute key initiatives; our ability to receive milestone payments from our partners; our expectations about cash runway; and the ability of our product candidates to treat their respective target CNS disorders. These forward-looking statements may be accompanied by such words as “aim,” “anticipate,” “believe,” “could,” “estimate,” “expect,” “forecast,” “goal,” “intend,” “may,” “might,” “plan,” “potential,” “possible,” “will,” “would,” and other words and terms of similar meaning. These statements involve risks and uncertainties that could cause actual results to differ materially from those reflected in such statements, including: our ability to develop and obtain regulatory approval for our product candidates; the timing and results of preclinical studies and clinical trials; risks associated with clinical trials, including our ability to adequately manage clinical activities, unexpected concerns that may arise from additional data or analysis obtained during clinical trials, regulatory authorities may require additional information or further studies, or may fail to approve or may delay approval of our drug candidates; the occurrence of adverse safety events; the risk that positive results in a preclinical study or clinical trial may not be replicated in subsequent trials or success in early stage clinical trials may not be predictive of results in later stage clinical trials; failure to protect and enforce our intellectual property, and other proprietary rights; our dependence on collaborators and other third parties for the development and manufacture of product candidates and other aspects of our business, which are outside of our full control; risks associated with current and potential delays, work stoppages, or supply chain disruptions; and the other risks and uncertainties that are described in the Risk Factors section in documents the company files from time to time with the Securities and Exchange Commission (SEC), and other reports as filed with the SEC. Passage Bio undertakes no obligation to publicly update any forward-looking statement, whether written or oral, that may be made from time to time, whether as a result of new information, future developments or otherwise.

3 REDEFINING THE COURSE OF NEURODEGENERATIVE CONDITIONS Advancing potential best-in-class, one-time progranulin raising FTD-GRN gene therapy In-house manufacturing process development to support program execution Strong cash position with runway expected to the end of 2Q 2026* Exploring benefits of elevated progranulin in multiple adult neurodegenerative diseases * Based on cash, cash equivalents and marketable securities as of June 30, 2024 and initial proceeds from out-licensing of pediatric programs.

4 Validating the Therapeutic Potential of PBFT02 Promising data from initial clinical study of PBFT02 in FTD-GRN Genetic form of FTD caused by GRN mutations, which lead to progranulin (PGRN) deficiency No approved disease-modifying therapies One-time therapy Proprietary AAV1 construct Nonsurgical injection directly to cerebrospinal fluid (CSF) Durable, elevated CSF PGRN levels* Urgent Patient Need in FTD-GRN Differentiated, Potential Best-in-Class Profile Fast Track and Orphan Drug Designation * Based on interim data.

5 Significant Market Opportunity for PBFT02 Across Multiple Neurodegenerative Diseases ~18,000 ~21,000 ~72,600 ~3.9M FTD-GRN1–3 FTD-C9orf722–4 AMYOTROPHIC LATERAL SCLEROSIS (ALS) 5–6 ALZHEIMER’S DISEASE (GRN SNP)*7–8 * rs5848 single nucleotide polymorphism (SNP) 1. Greaves CV, et al. J Neurol 2019; 266:2075-2086. 2. Galvin JE, et al. Neurology 2017; 89:2049-2056. 3. Onyike CU, et al. Int Rev Psychiatry 2013; 25:130-137. 4. Moore KM, et al. Lancet Neurol 2020; 19: 145–156. 5. Brown et al. Neuroepi 2021; 55:342-353. 6. CDC ALS Registry Dashboard. 7. Sheng J, et al. Gene 2014; 141-145. 8. Alz Assoc. 2023 Alzheimer’s Disease Facts and Figures. Alzheimers Dement 2023;19. Estimated Prevalence (US and EU)

6 Anticipated Upcoming Milestones and Data Readouts 2H 2024 1H 2025 2H 2025 Obtain regulatory feedback on the pathway to treating ALS patients Present updated safety and biomarker data from Cohort 1 patients at ISFTD2024 (Sep) Report 12-month Cohort 1 and interim Cohort 2 data FTD-GRN Milestones FTD-C9orf72 and ALS Milestones Initiate dosing of FTD-C9orf72 patients Seek regulatory feedback on pivotal trial design

PBFT02 Frontotemporal Dementia-GRN

8 FTD: A Devastating Adult Disease OVERVIEW • Fatal adult-onset neurodegenerative disease affecting the frontal and temporal lobes of the brain, characterized by a decline in behavior, language and executive function • One of the most common causes of early-onset dementia worldwide, disproportionately affecting individuals aged 40-65 years CLINICAL SYMPTOMS Disease progression is rapid and degenerative, including loss of speech, loss of expression, behavioral changes and immobility On average, people with FTD live 8 years after the onset of symptoms

9 Progranulin Deficiency is the Defining Characteristic of FTD-GRN and Leads to Neurodegeneration Progranulin is critical to maintaining CNS cell homeostasis Rhinn H et al. Trends Pharm Sci. 2022, 43:641-652.

10 Elevated PGRN Increases Potential for Improved Cellular Function • Progranulin is a secreted protein that binds to cell membrane receptors to affect multiple intracellular pathways –Major role is regulating intracellular lysosomal activity –Extracellular PGRN is endocytosed via multiple receptors • Driving elevated PGRN levels in the extracellular space increases the amount of PGRN available to enter target CNS cells • Able to leverage cross-correction mechanism: secreted PGRN can be taken up by non-transduced cells Paushter et al., Acta Neuropathol. 2018;136(1):1-17., Rhinn et al., Trends in Pharmacological Sciences 2022; 43.8:641-652.

11 Preclinical: AAV1 Achieved the Highest Levels of CSF PGRN in NHPs AAV1 increased CSF PGRN levels ~5x more than AAV5 and AAVhu68 (proprietary AAV9 variant) vectors, without further elevating peripheral levels Production of Human PGRN in Plasma AAV1 transgene delivery led to highest hPGRN levels in CSF CSF PGRN (ng/mL) 0 10 20 30 40 CSF 0.1 1 10 100 LLOQ Normal Day RA2981 RA2982 RA3027 RA3153 RA3151 RA3170 RA3155 RA3160 AAVhu68 AAVhu68 (v2) AAV1 AAV5 RA2981 RA2982 RA3027 RA3153 RA3151 RA3170 RA3155 RA3160 AAVhu68 AAVhu68 (v2) AAV1 AAV5 RA2981 RA2982 RA3027 RA3153 RA3151 RA3170 RA3155 RA3160 AAVhu68 AAVhu68 (v2) AAV1 AAVhu68 AAV5 AAVhu68 (v2) AAV5 AAV1 Normal LLOQ Plasma Plasma PGRN (ng/mL) 0 10 20 30 40 0.1 1 10 100 Normal Day 1,000 Left, right: Two adult rhesus macaques per treatment received ICM AAV.hPGRN High dose, 3.0 x 1013 GC / 3.3 x 1011 GC/g brain) on study day 01 .. Shading: Reference range for healthy adult controls’ PGRN levels in CSF (n = 61) and plasma (n = 56) (Passage Bio data).

12 Preclinical: Higher CSF PGRN May Confer Reduction in Inflammatory Response • Microgliosis: inflammatory response to pathogenic insults in the CNS • CD68: marker of activated microglia Thalamus data shown above. Thalamic atrophy is a key feature commonly found in FTD PBFT02 reduced lipofuscin at all doses, suggesting correction of underlying mechanism of disease • Lipofuscin: increased levels associated with lysosomal dysfunction • Correlated with underlying mechanism of FTD-GRN Microgliosis reduction strongest at highest PBFT02 dose / PGRN level Murine FTD Model Murine FTD Model *p < 0.05, **p < 0.01, ***p < 0.001, ****p < 0.0001, one-way ANOVA followed by Tukey’s multiple comparisons test

13 upliFT-D: Global Phase 1/2 Trial with PBFT02 DURATION 2 years; with additional 3 years of follow-up for safety and durability of effect PRIMARY ENDPOINTS Safety and tolerability SECONDARY ENDPOINTS Biomarkers • Progranulin (CSF, plasma) • GFAP (CSF, plasma) • vMRI • Retinal nerve fiber layer and retinal lipofuscin deposits via OCT • NfL (CSF, plasma) Clinical • CDR + NACC FTLD sum of boxes EXPLORATORY BIOMARKERS • Cathepsin D (CSF) • LAMP 1 (CSF) • Lys-GL1 (CSF) COHORT 1 Dose 1 (3.3e10 GC/g)* COHORT 2 Dose 2 (1.1e11 GC/g)* OPTIONAL COHORT 3 Optional dose 3 Recruiting IDMC review Phase 1/2 Multicenter Open-label Dose escalation study Up to 15 patients across 3 cohorts 1/2 TRIAL DESIGN COHORT 1 (n=5) Dose 1 COHORT 2 (n=3-5) Dose 1 OPTIONAL COHORT 3 IDMC review Phase Multicenter Open-label Dose escalation study Up to 15 patients across 3 cohorts 1/2 Complete Dose 1: 3.3e10 GC/g estimated brain weight.

14 Intra-Cisterna Magna (ICM) Administration • Directly deliver vector into the CSF via a single injection to reach both CNS and peripheral tissues1 –Allows for broad CNS biodistribution –Lower doses compared to IV systemic delivery –Reduced impact of neutralizing antibodies • Brief (<60 min), non-surgical, CT-guided procedure to allow for precise delivery to the cisterna magna –Infusion catheter does not enter brain tissues Cisterna magna 1. Hinderer et. al, Human Gene Therapy. 2018 Jan; 29(1):15-24​.

15 upliFT-D: Interim Data from Cohort 1 Patients • PBFT02 was well-tolerated among the four patients (P2-5) who received revised immunosuppression regimen –Among these patients, there were no SAEs; only mild-to-moderate treatment emergent AEs were reported • No evidence of DRG toxicity, as measured by nerve conduction studies • No complications related to ICM administration observed Safety* Efficacy / Target Engagement • Interim data demonstrates PBFT02 potential for best-in-class efficacy at Dose 1 • Dose 1 showed continued elevation of CSF PGRN levels at up to six months post-treatment: 21.7 – 27.3 ng/mL (n=2) SAE: serious adverse event; AE: adverse event; DRG: dorsal root ganglion; ICM: intracisterna magna *Patient safety follow-up ranged from 2 to 12 months post-dosing as of data cutoff of June 17, 2024

16 • Potential best-in-class PGRN profile at Dose 1 • Continued elevation of CSF PGRN at 6-months (n=2) • Consistent response across first three treated patients Initial Patients Treated with PBFT02 Have Seen a Substantial Increase in CSF PGRN At Dosing D30 D60 D180 Patient 1 1.9 12.7 N/A N/A Patient 2 2.8 17.3 N/A 27.3 Patient 3 2.9 10.7 13.7 21.7 CSF Progranulin (ng/mL) Shading: Reference range for healthy adult controls’ PGRN levels in CSF (range: 3.28 – 8.15 ng/mL, mean: 4.76 ng/mL, n = 61) (Passage Bio data) CSF=Cerebrospinal fluid 0 3 6 9 12 15 18 21 24 27 30 0 30 60 90 120 150 180 CSF PGRN, ng/mL Time (days) Dose 1 Progranulin, CSF Patient 1 Patient 2 Patient 3

17 • Plasma PGRN levels remained below normal levels at up to 6 months post-dose • PGRN increased only in the CSF where it has potential to correct deficit associated with neurodegeneration Plasma PGRN Levels Remained Below Normal Levels Post-Dose Shading: Lower limit of normal reference range for healthy adult controls’ PGRN levels in plasma (91.6 – 372.4 ng/mL, n = 56) (Passage Bio data) 0 10 20 30 40 50 60 70 80 90 100 0 7 14 30 60 90 120 150 180 Plasma PGRN, ng/mL Time (days) Dose 1 Progranulin, Plasma Patient 1 Patient 2 Patient 3

18 Summary SAFETY1 PBFT02 Dose 1 generally well-tolerated to date among the four Cohort 1 patients who received revised steroid regimen following protocol amendment • No serious AEs • All AEs mild to moderate in intensity • No evidence of clinically significant immune response, hepatotoxicity or venous sinus thrombosis • No evidence of DRG toxicity • No complications observed related to ICM injection BIOMARKERS • Potential best-in-class PGRN profile at Dose 1 • Continued elevation of CSF PGRN at 6-months (n=2) • Consistent response across first three treated patients •No increase in plasma PGRN levels up to Day 180 (n=3) ANTICIPATED NEXT STEPS • Present updated safety and biomarker data from Cohort 1 at ISFTD in Sep 2024 • Report 12-month Cohort 1 and interim Cohort 2 data in 1H 2025 • Seek regulatory feedback on pivotal trial design in 2H 2025 AEs=adverse events; ICM=intra-cisterna magna; DRG=dorsal root ganglia 1. Patient safety follow-up ranged from 2 to 12 months post-dosing as of data cutoff of June 17, 2024

Looking Ahead

20 PBFT02 has Potential to Correct Underlying Pathology in FTD-GRN, FTD-C9orf72 and ALS TDP-43 pathology is a hallmark of multiple neurodegenerative diseases1 • TDP-43 mislocalizes from nucleus to cytoplasm • Forms inclusion bodies associated with neurodegeneration 1. Rhinn H et al. Trends Pharm Sci. 2022, 43:641-652

21 TDP-43 pathology due to lysosomal dysfunction (GRN/ TMEM106 double knockout, DKO) reduced by AAV.hPGRN1 Elevated PGRN Ameliorates TDP-43 Pathology in Preclinical Models AAV delivered hPGRN to DKO mouse brain TDP-43 pathology in DKO mice reduced by AAV.hPGRN Elevated PGRN reduced insoluble TDP-43 in mouse spinal cord Elevated PGRN extended survival of TDP-43 mutant mice Elevated PGRN ameliorated TDP-43 pathology and disease course in a preclinical model2 • Elevated PGRN also prevented degeneration of large axon fibers in TDP-43 mice • PGRN neuroprotection from pleiotropic effect, not single pathway 1. Reich et al. (2023) bioRxiv preprint 07.14.549089; 2. Beel et al (2018) Mol Neurodegen; Laird et al. (2010) Plos One. DKO=double gene knockout; GRN=granulin gene; PGRN=progranulin; TDP-43=transactive response DNA binding protein 43 kDa. † PGRN increased to >2x endogenous levels

22 GRN rs5848 SNP associated with accelerated disease in FTD-C9orf72 patients Decreased PGRN Associated with Greater Disease Severity in Multiple CNS Conditions GRN rs5848 SNP associated with accelerated disease in FTD-C9orf72 patients 1. van Blitterswijk et al (2014) Mol Neurodegen. AD=Alzheimer’s disease; ALS=amyotrophic lateral sclerosis; GRN=granulin gene; PGRN=progranulin; SNP=single nucleotide polymorphism. PGRN SNPs are genetic risk factors for CNS diseases • GRN rs5848 SNP results in ~15% reduction in PGRN levels • PGRN SNPs increase risk for, and worsen severity of, FTD/ALS-C9orf72 and AD1

23 • GRN SNP rs5848 carriers have reduced PGRN levels and increased risk for AD • AD patients with GRN SNP rs5848 show reduced PGRN levels and increased CSF tau • GRN SNP rs5848 is estimated to occur in 30% of the general population, with a similar prevalence rate among AD patients2 • PGRN ablation exacerbates AD pathology in mice • PGRN overexpression reduces pathology burden in AD models Genetic Risk1 Prevalence Supporting Preclinical Evidence3 PBFT02 has Potential to Modulate Alzheimer’s Disease SNP=single nucleotide polymorphism. Third-party preclinical data. Sources: 1. Chen Y et al. J Neurol. 2015, 262:814-22; Takahashi H et al. Acta Neuropathol. 2017, 133:785-807. 2. Fenoglio C et al. J Alzheimers Dis. 2009, 18:603-612 (allele frequency used to estimate prevalence among AD patients). 3. Hosokawa M et al. J Neuropath Exp Neurol. 2015, 74:158-65; Minami SS et al. Nat Med. 2014, 20:1157-64; Van Kampen JM & Kay DG. PLoS ONE 2017, 12:e0182896.

24 Leading In-House CMC Capabilities to Support PBFT02 Development Proven analytical development capabilities In-House CMC Analytical Capabilities to Support Program Advancement and Future Commercialization of PBFT02 Integrated process development GMP QC capabilities Strong regulatory CMC scientific expertise Scale-up capability

25 Upcoming Milestones and Corporate Updates PIPELINE • Advancing Huntington’s disease preclinical program • Licensed pediatric clinical-stage programs (GM1, Krabbe and MLD) to GEMMA Biotherapeutics BALANCE SHEET • Cash balance of $92 million as of 6/30/24* • Cash runway to the end of 2Q 2026* * Based on cash, cash equivalents and marketable securities and initial proceeds from out-licensing of pediatric programs. TIMING MILESTONE FTD-GRN 2H 2024 Present updated safety and biomarker data from Cohort 1 at ISFTD conference in September 1H 2025 Report 12-month Cohort 1 and interim Cohort 2 data 2H 2025 Seek regulatory feedback on pivotal trial design PBFT02 Additional Indications 2H 2024 Obtain regulatory feedback on clinical pathway for treating ALS patients 1H 2025 Initiate dosing of FTD-C9orf72 patients

26 REDEFINING THE COURSE OF NEURODEGENERATIVE CONDITIONS Advancing potential best-in-class, one-time progranulin raising FTD-GRN gene therapy In-house manufacturing process development to support program execution Strong cash position with runway expected to the end of 2Q 2026* Exploring benefits of elevated progranulin in multiple adult neurodegenerative diseases * Based on cash, cash equivalents and marketable securities as of June 30, 2024 and initial proceeds from out-licensing of pediatric programs.

Thank You passagebio.com | NASDAQ: PASG

28 Focused Pipeline Addressing Rare and Prevalent Neurodegenerative Indications Program Indication US/EU prevalence Discovery Preclinical Phase 1/2 Pivotal PBFT02 Frontotemporal dementia - GRN 18,0001-3 Frontotemporal dementia - C9orf72 21,0002-4 Amyotrophic lateral sclerosis 72,6005-6 Alzheimer’s disease with rs5848 SNP 3.9M7-8 Unnamed Huntington’s disease 60,0009 PBGM01 GM1 gangliosidosis PBKR03 Krabbe disease PBML04 Metachromatic leukodystrophy Licensed to GEMMA Biotherapeutics 1. Greaves CV, et al. J Neurol 2019; 266:2075-2086. 2. Galvin JE, et al. Neurology 2017; 89:2049-2056. 3. Onyike CU, et al. Int Rev Psychiatry 2013; 25:130-137. 4. Moore KM, et al. Lancet Neurol 2020; 19: 145–156. 5. Brown et al. Neuroepi 2021; 55:342-353. 6. CDC ALS Registry Dashboard. 7. Sheng J, et al. Gene 2014; 141-145. 8. Alz Assoc. 2023 Alzheimer’s Disease Facts and Figures. Alzheimers Dement 2023;19. 9. Crowell et al. Neuroepi. 2021; 55:361-368

29 Demonstrated Leadership LEADERSHIP TEAM Deep experience in rare disease, CNS disorders and genetic medicines Eden Fucci SVP Technical Operations BOARD OF DIRECTORS Maxine Gowen, Ph.D. Chairwoman Athena Countouriotis, M.D. Avenzo Therapeutics Derrell Porter, M.D. cTRL Therapeutics Dolan Sondhi, Ph.D. Weill Cornell Medicine Sandip Kapadia Harmony Biosciences Saqib Islam, J.D. SpringWorks William Chou, M.D. President & Chief Executive Officer Stuart Henderson Chief Business Officer William Chou, M.D. President & Chief Executive Officer Chip Cale General Counsel & Corporate Secretary Kathleen Borthwick Chief Financial Officer Karl Whitney SVP Global Regulatory Affairs Sue Browne, Ph.D. Chief Scientific Officer

Document and Entity Information	Aug. 08, 2024
Document and Entity Information [Abstract]
Document Type	8-K
Document Period End Date	Aug. 08, 2024
Entity File Number	001-39231
Entity Registrant Name	PASSAGE BIO, INC.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	82-2729751
Entity Address, Address Line One	One Commerce Square
Entity Address, Adress Line Two	2005 Market Street, 39th Floor
Entity Address, City or Town	Philadelphia
Entity Address, State or Province	PA
Entity Address, Postal Zip Code	19103
City Area Code	267
Local Phone Number	866-0311
Written Communications	false
Soliciting Material	false
Pre-commencement Tender Offer	false
Pre-commencement Issuer Tender Offer	false
Title of 12(b) Security	Common Stock, $0.0001 Par Value Per Share
Trading Symbol	PASG
Security Exchange Name	NASDAQ
Entity Emerging Growth Company	true
Entity Ex Transition Period	false
Entity Central Index Key	0001787297
Amendment Flag	false

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