[SCHEDULE 13D/A] Passage Bio, Inc. SEC Filing

Rhea-AI Filing Summary

Amendment No. 8 to Schedule 13D shows that OrbiMed Advisors LLC and OrbiMed Capital GP VII LLC have reduced their Passage Bio (PASG) holding.

• After the 1-for-20 reverse split effective 14 Jul 2025, OrbiMed controls 243,878 common shares, or 7.82 % of PASG’s 3.12 m shares outstanding.
• The position is owned through OrbiMed Private Investments VII, LP; both OrbiMed entities share voting & dispositive power.
• Decline in ownership (>1 pp) stems from a series of open-market sales between 24 Jun-17 Jul 2025: 86k+ shares sold at $0.33-$0.48 pre-split and $5.83-$6.77 post-split.
• No plans for corporate actions were announced; OrbiMed may buy or sell further based on market conditions.

Despite trimming the stake, OrbiMed remains a major shareholder with registration rights under the 2019 Investors’ Rights Agreement, maintaining potential influence over PASG’s strategic direction.

Positive

• OrbiMed retains a 7.82 % ownership position, continuing to align with existing shareholders.
• Registration and demand/piggyback rights under the 2019 Investors’ Rights Agreement remain available, supporting future capital-market flexibility.

Negative

• Stake reduced by more than 1 percentage point through open-market sales, implying tempered confidence.
• Sales executed at very low pre-split prices ($0.33-$0.48), indicating a willingness to exit at depressed valuations.

Insights

Biotech Buy-side Analyst

TL;DR: OrbiMed’s cut signals caution; still sizable 7.8 % stake maintains influence.

The disposal of roughly 26 % of OrbiMed’s pre-split position suggests diminished conviction in Passage Bio’s near-term prospects, especially given sales at sub-$0.50 levels before the reverse split. The remaining holding, however, keeps OrbiMed among the top shareholders, offering optionality if upcoming clinical milestones improve sentiment. Overall, the action is modestly negative for equity perception but not a full exit.

Corporate Governance Specialist

TL;DR: Filing is impactful; ownership drop triggers updated disclosure but no governance changes.

The amendment is required because the stake fell below the prior 9 % level. Importantly, OrbiMed reiterates no intent to force strategic moves, reducing takeover speculation. Registration rights remain intact, ensuring future liquidity. Shareholders should watch for further sales, which could pressure float in the short term.

SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

SCHEDULE 13D

Under the Securities Exchange Act of 1934

(Amendment No. 8)

Passage BIO, Inc.

(Name of Issuer)

COMMON STOCK

(Title of Class of Securities)

702712100

(CUSIP Number)

OrbiMed Advisors LLC
601 Lexington Avenue, 54th Floor
New York, NY, 10022
2127396400

(Name, Address and Telephone Number of Person Authorized to Receive Notices and Communications)

07/17/2025

(Date of Event Which Requires Filing of This Statement)

If the filing person has previously filed a statement on Schedule 13G to report the acquisition that is the subject of this Schedule 13D, and is filing this schedule because of §§ 240.13d-1(e), 240.13d-1(f) or 240.13d-1(g), check the following box.

The information required on the remainder of this cover page shall not be deemed to be "filed" for the purpose of Section 18 of the Securities Exchange Act of 1934 ("Act") or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes).

SCHEDULE 13D

CUSIP No. 702712100

1

Name of reporting person

ORBIMED ADVISORS LLC

2

Check the appropriate box if a member of a Group (See Instructions)

(a)
(b)

3

SEC use only

4

Source of funds (See Instructions)

AF

5

Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)

6

Citizenship or place of organization

DELAWARE

Number of Shares Beneficially Owned by Each Reporting Person With:

7	Sole Voting Power 0.00
8	Shared Voting Power 243,878.00
9	Sole Dispositive Power 0.00
10	Shared Dispositive Power 243,878.00

11

Aggregate amount beneficially owned by each reporting person

243,878.00

12

Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)

13

Percent of class represented by amount in Row (11)

7.82 %

14

Type of Reporting Person (See Instructions)

IA

SCHEDULE 13D

CUSIP No. 702712100

1

Name of reporting person

ORBIMED CAPITAL GP VII LLC

2

Check the appropriate box if a member of a Group (See Instructions)

(a)
(b)

3

SEC use only

4

Source of funds (See Instructions)

AF

5

Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)

6

Citizenship or place of organization

DELAWARE

Number of Shares Beneficially Owned by Each Reporting Person With:

7	Sole Voting Power 0.00
8	Shared Voting Power 243,878.00
9	Sole Dispositive Power 0.00
10	Shared Dispositive Power 243,878.00

11

Aggregate amount beneficially owned by each reporting person

243,878.00

12

Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)

13

Percent of class represented by amount in Row (11)

7.82 %

14

Type of Reporting Person (See Instructions)

OO

SCHEDULE 13D

Item 1.	Security and Issuer
(a)	Title of Class of Securities: COMMON STOCK
(b)	Name of Issuer: Passage BIO, Inc.
(c)	Address of Issuer's Principal Executive Offices: One Commerce Square, 2005 Market Street, 39th Floor, Philadelphia, PENNSYLVANIA , 19103.
Item 1 Comment: This Amendment No. 8 ("Amendment No. 8") to Schedule 13D supplements and amends the Statement on Schedule 13D of OrbiMed Advisors LLC ("OrbiMed Advisors") and OrbiMed Capital GP VII LLC ("OrbiMed GP") (collectively, the "Reporting Persons") originally filed with the Securities and Exchange Commission (the "SEC") on March 9, 2020 with OrbiMed Capital LLC as an additional reporting person, as amended by Amendment No. 1 filed with the SEC on January 28, 2021, Amendment No. 2 filed with the SEC on May 5, 2022, Amendment No. 3 filed with the SEC on June 29, 2023, Amendment No. 4 filed with the SEC on April 12, 2024, Amendment No. 5 filed with the SEC on December 26, 2024, Amendment No. 6 filed with the SEC on April 25, 2025, and Amendment No. 7 filed with the SEC on July 9, 2025. This Amendment No. 8 is being filed to report that the beneficial ownership of the outstanding Shares held by the Reporting Persons decreased by more than 1% as a result of the transactions described in Item 5(c) below. On June 26, 2025, the Issuer's Board of Directors approved a 1-for-20 reverse stock split (the "Reverse Stock Split"), which was effective on July 14, 2025. All Shares reported in this Amendment No. 8 are presented on an after-Reverse Stock Split basis.
Item 2.	Identity and Background
(a)	OrbiMed Advisors, a limited liability company organized under the laws of Delaware and a registered investment adviser under the Investment Advisers Act of 1940, as amended. OrbiMed GP, a limited liability company organized under the laws of Delaware. Carl L. Gordon, a United States citizen. Sven H. Borho, a German and Swedish citizen. W. Carter Neild, a United States citizen. Geoffrey C. Hsu, a United States citizen. C. Scotland Stevens, a United States citizen. David P. Bonita, a United States citizen. Peter A. Thompson, a United States citizen. Matthew S. Rizzo, a United States citizen. Trey Block, a United States citizen.
(b)	601 Lexington Avenue, 54th Floor, New York, New York 10022.
(c)	OrbiMed Advisors is the managing member or general partner of certain entities as more particularly described in Item 6 below. OrbiMed GP is the general partner of a limited partnership as more particularly described in Item 6 below. Carl L. Gordon is a member of OrbiMed Advisors. Sven H. Borho is a member of OrbiMed Advisors. W. Carter Neild is a member of OrbiMed Advisors. Geoffrey C. Hsu is a member of OrbiMed Advisors. C. Scotland Stevens is a member of OrbiMed Advisors. David P. Bonita is a member of OrbiMed Advisors. Peter A. Thompson is a member of OrbiMed Advisors. Matthew S. Rizzo is a member of OrbiMed Advisors. Trey Block is the Chief Financial Officer of OrbiMed Advisors.
(d)	Not applicable.
(e)	Not applicable.
(f)	Item 2(a) is incorporated herein by reference.
Item 3.	Source and Amount of Funds or Other Consideration
	Not applicable.
Item 4.	Purpose of Transaction
	The Reporting Persons from time to time intend to review their investment in the Issuer on the basis of various factors, including the Issuer's business, financial condition, results of operations and prospects, general economic and industry conditions, the securities markets in general and those for the Issuer's Shares in particular, as well as other developments and other investment opportunities. Based upon such review, the Reporting Persons will take such actions in the future as the Reporting Persons may deem appropriate in light of the circumstances existing from time to time. If the Reporting Persons believe that further investment in the Issuer is attractive, whether because of the market price of Shares or otherwise, they may acquire Shares or other securities of the Issuer either in the open market or in privately negotiated transactions. Similarly, depending on market and other factors, the Reporting Persons may determine to dispose of some or all of the Shares currently owned by the Reporting Persons or otherwise acquired by the Reporting Persons either in the open market or in privately negotiated transactions. Except as set forth in this Schedule 13D, the Reporting Persons have not formulated any plans or proposals which relate to or would result in: (a) the acquisition by any person of additional securities of the Issuer or the disposition of securities of the Issuer, (b) an extraordinary corporate transaction, such as a merger, reorganization or liquidation, involving the Issuer or any of its subsidiaries, (c) a sale or transfer of a material amount of the assets of the Issuer or any of its subsidiaries, (d) any change in the present Board of Directors or management of the Issuer, including any plans or proposals to change the number or term of directors or to fill any existing vacancies on the board, (e) any material change in the Issuer's capitalization or dividend policy of the Issuer, (f) any other material change in the Issuer's business or corporate structure, (g) any change in the Issuer's charter or bylaws or other instrument corresponding thereto or other action which may impede the acquisition of control of the Issuer by any person, (h) causing a class of the Issuer's securities to be deregistered or delisted from a national securities exchange or to cease to be authorized to be quoted in an inter-dealer quotation system of a registered national securities association, (i) a class of equity securities of the Issuer becoming eligible for termination of registration pursuant to Section 12(g)(4) of the Act or (j) any action similar to any of those enumerated above.
Item 5.	Interest in Securities of the Issuer
(a)	The following disclosure is based upon 3,120,295 outstanding Shares of the Issuer, as set forth in the Issuer's Current Report on Form 8-K filed with the SEC on July 14, 2025. As of the date of this filing, OrbiMed Private Investments VII, LP ("OPI VII"), a limited partnership organized under the laws of Delaware, holds 243,878 Shares constituting approximately 7.82% of the issued and outstanding Shares. OrbiMed GP is the general partner of OPI VII, pursuant to the terms of the limited partnership agreement of OPI VII, and OrbiMed Advisors is the managing member of OrbiMed GP, pursuant to the terms of the limited liability company agreement of OrbiMed GP. As a result, OrbiMed Advisors and OrbiMed GP share power to direct the vote and disposition of the Shares held by OPI VII and may be deemed directly or indirectly, including by reason of their mutual affiliation, to be the beneficial owners of the Shares held by OPI VII. OrbiMed Advisors exercises this investment and voting power through a management committee comprised of Carl L. Gordon, Sven H. Borho, and W. Carter Neild, each of whom disclaims beneficial ownership of the Shares held by OPI VII.
(b)	Item 5(a) is incorporated by reference herein.
(c)	On June 24, 2025, OPI VII sold 11,580 Shares at a price of $0.35 per Share. On June 25, 2025, OPI VII sold 6,940 Shares at a price of $0.33 per Share. On June 26, 2025, OPI VII sold 10,662.85 Shares at a price of $0.33 per Share. On June 27, 2025, OPI VII sold 552.15 Shares at a price of $0.34 per Share. On July 7, 2025, OPI VII sold 1,198 Shares at a price of $0.48 per Share. On July 8, 2025, OPI VII sold 2,535 Shares at a price of $0.43 per Share. On July 9, 2025, OPI VII sold 2,855.30 Shares at a price of $0.44 per Share. On July 10, 2025, OPI VII sold 6,361.70 Shares at a price of $0.40 per Share. On July 15, 2025, OPI VII sold 3,700 Shares at a price of $6.77 per Share. On July 16, 2025, OPI VII sold 20,048 Shares at a price of $5.86 per Share. On July 17, 2025, OPI VII sold 22,188 Shares at a price of $5.83 per Share. The Reporting Persons undertake, upon request by the staff of the SEC or the Issuer to provide full information regarding the number of Shares sold at each separate price.
(d)	Not applicable.
(e)	Not applicable.
Item 6.	Contracts, Arrangements, Understandings or Relationships With Respect to Securities of the Issuer
	In addition to the relationships between the Reporting Persons described in Items 2 and 5 above, OrbiMed GP is the general partner of OPI VII, pursuant to the terms of the limited partnership agreement of OPI VII. Pursuant to this agreement and relationship, OrbiMed GP has discretionary investment management authority with respect to the assets of OPI VII. Such authority includes the power to vote and otherwise dispose of securities held by OPI VII. The number of outstanding Shares attributable to OPI VII is 243,878 Shares. OrbiMed GP, pursuant to its authority under the limited partnership agreement of OPI VII, may be considered to hold indirectly 243,878 Shares. In addition to the relationships between the Reporting Persons described in Items 2 and 5 above, OrbiMed Advisors is the managing member of OrbiMed GP, pursuant to the terms of the limited liability company agreement of OrbiMed GP. Pursuant to these agreements and relationships, OrbiMed Advisors and OrbiMed GP have discretionary investment management authority with respect to the assets of OPI VII. Such authority includes the power of OrbiMed GP to vote and otherwise dispose of securities held by OPI VII. The number of outstanding Shares attributable to OPI VII is 243,878 Shares. OrbiMed Advisors, pursuant to its authority under the terms of the limited liability company agreement of OrbiMed GP, may also be considered to hold indirectly 243,878 Shares. Investors' Rights Agreement In addition, OPI VII, the Worldwide Healthcare Trust PLC, and certain other stockholders of the Issuer entered into an amended and restated investors' rights agreement with the Issuer (the "Investors' Rights Agreement"), dated as of August 21, 2019. Pursuant to the Investors' Rights Agreement and subject to the terms and conditions therein, the parties agreed that: Registration Rights Following the closing of the Issuer's initial public offering (the "IPO"), the holders of a certain number of Shares, or their transferees, will be entitled to the registration rights set forth below with respect to registration of the resale of such Shares under the Securities Act of 1933, as amended (the "Securities Act") pursuant to the Investors' Rights Agreement. Demand Registration Rights At any time beginning six months following the date of the underwriting agreement of the IPO, the holders of at least thirty percent (30%) of the registrable securities then outstanding of the Issuer may make a written request that the Issuer register at least thirty percent (30%) of the registrable securities then outstanding, subject to certain specified conditions and exceptions. The Issuer is required to use commercially reasonable efforts to effect the registration and will pay all registration expenses, other than underwriting discounts and commissions, related to any demand registration. The Issuer is not obligated to effect more than two of these registrations. Piggyback Registration Rights Whenever the Issuer proposes to file a registration statement under the Securities Act, including a registration statement on Form S-3 as discussed below, other than with respect to certain excluded registrations, the Reporting Persons will be entitled to notice of the registration and have the right, subject to limitations that the underwriters may impose on the number of Shares included in the registration, to include Shares held by the Reporting Persons in the registration. Form S-3 Registration Rights At any time after the Issuer is qualified to file a registration statement on Form S-3 under the Securities Act, and subject to limitations and conditions specified in the Investors' Rights Agreement, holders of at least twenty-five percent (25%) of the Registrable Securities (as defined in the Investors' Rights Agreement) then outstanding may make a written request that the Issuer prepare and file a registration statement on Form S-3 covering their Shares, so long as the aggregate price to the public equals or exceeds $3,000,000. The Issuer is not obligated to effect more than two of these Form S-3 registrations in any 12-month period. The foregoing description of the Investors' Rights Agreement does not purport to be complete and is qualified in its entirety by reference to the full texts of the Investors' Rights Agreement, which is filed as Exhibit 2 and incorporated herein by reference.
Item 7.	Material to be Filed as Exhibits.
	------------------------------------------------------------------------------------------------------------------------------------ Exhibit Description ------------------------------------------------------------------------------------------------------------------------------------ 1. Joint Filing Agreement among OrbiMed Advisors LLC and OrbiMed Capital GP VII LLC. ------------------------------------------------------------------------------------------------------------------------------------ 2. Amended and Restated Investors' Rights Agreement by and among the Issuer and certain of its stockholders, dated as of August 21, 2019 (incorporated by reference to Exhibit 4.2 to the Issuer's Registration Statement on Form S-1 (File No. 333-236214), filed with the SEC on February 3, 2020). ------------------------------------------------------------------------------------------------------------------------------------

SIGNATURE

After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

ORBIMED ADVISORS LLC

Signature:	/s/ Carl L. Gordon
Name/Title:	Carl L. Gordon/Member
Date:	07/21/2025

ORBIMED CAPITAL GP VII LLC

Signature:	/s/ Carl L. Gordon
Name/Title:	Carl L. Gordon/Member of OrbiMed Advisors LLC
Date:	07/21/2025

FAQ

How much Passage Bio (PASG) stock does OrbiMed now own?

Post reverse split, OrbiMed reports 243,878 shares, or 7.82 % of outstanding common stock.

Why did OrbiMed file Amendment No. 8 to its Schedule 13D?

Because its beneficial ownership fell by more than 1 % following share sales between 24 Jun-17 Jul 2025.

What prices did OrbiMed sell PASG shares for?

Pre-split: $0.33-$0.48; post-split: $5.83-$6.77 per share.

Does OrbiMed plan further corporate actions at Passage Bio?

The filing states no current plans for mergers, board changes or capital actions; OrbiMed may still buy or sell based on market conditions.

What is the significance of PASG’s 1-for-20 reverse split?

Effective 14 Jul 2025, the reverse split increased the stock price proportionally and reduced shares outstanding; all figures in the filing are post-split.