Fifth Amendment to Amended and Restated Research, License & Collaboration Agreement, dated August 3, 2021, by and between the Registrant and the Trustees of the University of Pennsylvania

The definition of CNS Field set forth in Section 2.7 of the Agreement is hereby revised as follows:

All references to “for a CNS Monogenic Rare Disorder” in Sections 2.6.1 and 2.6.2 in the Agreement are hereby revised to “for a disorder in the CNS Field” and all references to “Available Rare CNS Indication” in Sections 2.6.1 and 2.6.2 in the Agreement are revised to “Available CNS Indication”.

For clarity, [*].

The following definition of the Agreement are hereby amended and restated:

Section 2.7 is hereby deleted in its entirety and replaced by the following paragraphs:

CNS Monogenic Rare Disorders. Without limiting Section 2.11.1, during the period starting on the Effective Date and ending at the earlier of: (a) [*], or (b) [*], Penn shall not grant any right to any commercial Third Party to any Patent Rights [*] or the Research Program for a Gene Therapy Product for any Available Rare CNS Indications without first notifying Licensee in writing, in which case Licensee shall have [*] from receipt of such notice to exercise its option with respect to such New Indication in accordance with the New Indication Option procedure set forth in Section 2.6.1. “Available Rare CNS Indication” means an indication in the field of CNS Monogenic Rare Disorders to the extent such New Indication is not listed on Exhibit D as specifically excluded from the CNS Field. Licensee acknowledges that the foregoing option will not apply to those New Indications set forth on Exhibit D. In addition during the Discovery Term and prior to Licensee’s exercise of its eleven (11) New Indication Options, subject to the terms of this Agreement, [*]. For clarity, [*].

CNS Non-Rare Disorders. Without limiting Section 2.11.1, during the period starting on the Effective Date and ending on the earlier of: (a) three (3) years thereafter (or such longer period subject to mutual written agreement between the Parties), or (b) Licensee’s exercise of its eleven (11) New Indication Options (“Exploratory Option Period”), [*] without first notifying Licensee in writing, in which case Licensee shall have [*] from receipt of such notice to exercise its option with respect to such New Indication in accordance with the New Indication Option procedure set forth in Section 2 of this Fifth Amendment. Upon expiration of the Exploratory

Exhibit D of the Agreement is hereby amended and replaced in its entirety by the new Exhibit D, attached as Exhibit 4 to this Amendment.

Exhibit F of the Agreement is hereby amended and replaced in its entirety by the new Exhibit F, attached as Exhibit 5 to this Amendment.

During the period following the Fifth Amendment Effective Date until the fifth (5^th) anniversary thereof, the Parties will collaborate with respect to the Exploratory Research Program, [*] (each an “Exploratory Research Plan”) for one or more product candidates (each an “Exploratory Candidate”). [*].

Licensee shall fund each Exploratory Research Plan in the amount set forth therein (“Exploratory Research Support Amount”). The Exploratory Research Support Amount is intended to fund Penn’s activities under the applicable Exploratory Research Plan. Such Exploratory Research Support Amount shall be inclusive of Penn’s standard indirect charges and all funding shall be paid in advance of any Exploratory Research Program work being conducted. Licensee shall remit such funds to Penn in accordance with the payment schedule set forth in the applicable Exploratory Research Plan. Notwithstanding the foregoing, [*].

The Exploratory Research Program will be subject to Sections 2.2.3, 2.2.4, 2.2.5 (first sentence), and 2.2.6, mutatis mutandis. For clarity, [*].

Penn will [*] conduct the Exploratory Research Program in accordance with the applicable Exploratory Research Plan(s) and the other terms and conditions of the Agreement. Upon completion of the applicable Exploratory Research Plan, Penn shall promptly deliver to Licensee a data package for each applicable product candidate [*] (“Exploratory [*] Data Package”). The contents of the data package will be [*]. If Licensee has interest to include an Exploratory Candidate in the License granted under the Agreement, Licensee shall formally notify Penn in writing within [*] following delivery of the Exploratory [*] Data Package of its interest in further developing such Exploratory Candidate, Penn will develop and propose within [*] a work plan and budget for the preclinical development costs through IND-enabling studies to be conducted at Penn for a Designated Product subject to reasonable review and approval by Licensee to be deemed a New Program Budget. Within [*] of Licensee’s receipt of the work plan and budget, Licensee shall decide whether to exercise a New Indication Option. If Licensee exercises a New Indication Option by written notice to Penn, then (a) the Parties will amend the Research Program and Research Plan to include such new program for the Exploratory Candidate, (b) the Research Support Amount will be increased by the amount of the New Program Budget, (c) Licensee will pay the New Indication Option Fee and (d) the definition of “Indication” will be amended to

Any Patent Rights arising from the Exploratory Research Program shall be deemed [*].

In consideration for the expansion of the CNS Field as set forth in Section 1.1 above and Penn’s commitment to perform the Exploratory Research Program as set forth in Section 2.4 above, Licensee will pay to Penn:

a one-time fee equal to Five Million US Dollars ($5,000,000) within ten (10) days following the Fifth Amendment Effective Date.

If, during the Term, a Transaction is consummated, Licensee shall pay to Penn (in cash and/or equity, in the same proportion as is paid to Licensee or the stockholders of Licensee pursuant to such Transaction), a one-time tiered fee equal to [*] percent ([*]) of the Net Proceeds from such Transaction up to and including $[*], [*] percent ([*]) of the Net Proceeds from such Transaction for all amounts greater than $[*] and less than $[*] and [*] percent ([*]) of the Net Proceeds from such Transaction for all amounts equal to or greater than $[*] (“Transaction Fee”). The Transaction Fee shall be paid to Penn within [*] after the consummation of such Transaction (or, to the extent Net Proceeds are received after such consummation, within [*] after their receipt). For clarity, Licensee’s obligations under this Section 3.1(b) will terminate upon [*]. “Net Proceeds” means the aggregate consideration [*]. For clarity, [*]. When determining the Transaction Fee, all amounts paid to Licensee and/or the stockholders of Licensee, as applicable, constituting Net Proceeds are cumulative. For example, [*]. “Transaction” shall mean the consummation of any of the following events: (i) [*]; (ii) [*]; or (iii) [*]. For clarity, all rights and other obligations of Licensee under the Agreement shall continue to be in effect in the event of a Transaction pursuant to the provisions of Section 11.6.

To the extent Licensee, any of its Affiliates or Sublicensees achieves any Development Milestone set forth in Section 4.2.1 of the Agreement with respect to any Licensed Product arising from the Exploratory Research Program for an Indication that is not a CNS Monogenic Rare Disorder, then the milestone amounts set forth in Section 4.2.1(a) of the Agreement shall be replaced with the amounts as set forth in Exhibit 1.

Any Licensed Product arising from the Exploratory Research Program shall be subject to the diligence requirements set forth in Article 5 of the Agreement.

Section 3.1.1(d) of the Agreement is hereby amended and restated as follows:

The last sentence of Section 2.10.2(b) of the Agreement is hereby deleted in its entirety and replaced with the following sentence: “Licensee may provide the foregoing notification with respect to a Licensed Product at or following Clinical Candidate Designation. “Clinical Candidate Designation” means the point in time when a Gene Therapy Product for a lead Indication with a specific capsid and vector genome has achieved the criteria set forth in [*] (attached as Exhibit J), as determined by the JSC in accordance with Section 2.14.1.” Additionally, all references to “Product Lock”, in Sections 2.10.3 and 2.11 of the Agreement shall be amended and replaced with references to “IND Clearance”, and the reference to “Product Lock” in Section 2.10.2(c) shall be amended and replaced with “Licensee’s delivery of a notification of a Specified Licensed Product under Section 2.10.2(b)”.

Exhibit 2 of this Amendment is hereby attached to the Agreement as a new Exhibit J.

Without limiting Section 5.1 above, Penn will [*].

The following new definition is hereby added as a new Section 1.82 to the Agreement:

To the extent the License with respect to a Licensed Product is expanded to additional indications as set forth in Section 5.1 above, the DRG License will automatically be expanded to the [*]. “DRG Excluded Indications” means [*].

To the extent a product is a [*], then the (a) royalty table set forth in Section 4.3.1 of the Agreement solely for such Licensed Product shall be replaced by a single royalty rate equal to [*] of Net Sales for such Licensed Product, and (b) the milestone amounts set forth in Section 4.2.1(a) of the Agreement solely for such Licensed Product shall be replaced with the amounts set forth on Exhibit 3; provided that Section 4.4 of the Agreement shall apply to such Licensed Product.

The first sentence of Section 2.11 of the Agreement is hereby revised as follows:

Section 2.12 of the Agreement is hereby revised as follows:

On a case-by-case basis, Passage may perform, at its sole expense, pre-IND activities contemplated under the Research Program (including IND-enabling studies) outside of the Wilson Laboratory upon [*].

Upon DTP for a Licensed Product, on a Licensed Product-by-Licensed Product basis, Penn will transfer to Licensee or its designee all copies of all written, graphic or electronic embodiments of the applicable Licensed Know-How and the Licensed Materials to Passage in accordance [*].

[*].

“Discovery Term” is hereby amended to mean the period commencing on January 1, 2016 and expiring five (5) years after the Fifth Amendment Effective Date, unless otherwise extended by the Parties. For clarity, the Discovery Funding Payment shall be paid each Calendar Quarter during the Discovery Term.

Section 5.8 is hereby amended with the addition of the following Section 5.8.2:

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