Exhibit 10.34

Confidential Materials omitted and filed separately with the
Securities and Exchange Commission. Double asterisks denote omissions.

Amendment No.1 to Master Research Services Agreement
By and Between
The Children’s Hospital of Philadelphia and Spark Therapeutics, Inc.

This amendment is made and entered into March 10, 2016 (the “Effective Date”) by
and between The Children’s Hospital of Philadelphia, a Pennsylvania nonprofit
corporation with its principal place of business at 34th Street and Civic Center
Boulevard, Philadelphia, PA 19104 (“CHOP”) and Spark Therapeutics, Inc.,
(formerly known as AAVenue Therapeutics, LLC) a Delaware corporation with its
principal place of business at 3737 Market Street, Suite 1300, Philadelphia, PA
19104 (“Spark Therapeutics”) (the “Amendment”).

Background
WHEREAS, Spark Therapeutics and CHOP entered into a Master Research Services
Agreement dated October 14, 2013 (the “Agreement”);
WHEREAS, the Term of the Agreement for products other than RPE65 expired upon
the completion of Services under the last work order executed by the parties
prior to July 1, 2015;
WHEREAS, the parties desire to extend the Term of the Agreement for the Other
Products.
NOW THEREFORE, in consideration of the premises and the mutual covenants
contained herein, and intending to be legally bound hereby, the parties hereto
agree as follows:
1.
Manufacturing Price. Section 1.15 of the Agreement is hereby deleted in its
entirety and replaced with the following:

“Manufacturing Price” shall mean, with respect to a Product, the agreed upon
price for the Product set forth on the agreed upon Work Order for such Product,
which shall consist of labor, materials and the other specified overhead costs
as set forth on Exhibit B. Any additional Work Orders for such Product shall not
exceed the original rate set forth on the original Work Order, increased by an
amount equal to the change in the Consumer Price Index, published by the United
States Bureau of Labor Statistics as of the date of the new Work Order, unless
such increase is a direct result of an increase in cost of services or materials
incurred by CHOP outside of CHOP’s control. CHOP shall provide information to
justify such increase in costs, if requested by Spark.”

2.
Capacity and Priority. Section 2.2 is hereby amended by deleting from the last
sentence of the section the following: “, and in the case of all Products, shall
use reasonable efforts to accommodate requests by AAVT for manufacturing in
excess of such capacity requirements.”

3.
Product. The definition of Product is hereby deleted in its entirety and
replaced with the following:

““Product” shall mean each viral vector product manufactured by CHOP and
purchased by AAVT from CHOP as set forth in a Work Order, including Custom
Product, unless otherwise specified.”

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4.
Custom Products. A new Section 2.6 is hereby added to the Agreement immediately
following Section 2.5 which shall read in its entirety as set forth below:

“Custom Products. For Products manufactured using a method not previously
qualified by CHOP (hereafter referred to as “Custom Products”), Spark
Therapeutics (formerly AAVT) will provide the manufacturing method to CHOP using
a formal technology transfer. For Custom Products, and after a protocol change
in a qualified process that may affect manufacturing or release, CHOP will
perform a process qualification run at cost to Spark Therapeutics and perform
limited testing (for information only) to verify protocol performance. CHOP will
provide samples from a qualification run (if requested by Spark) to allow Spark
Therapeutics to verify performance. Spark Therapeutics will be required to
formally accept completion of the technology transfer and agree that the
transferred method (as used by CHOP) is acceptable for manufacture of the
Product. Once a manufacturing method is transferred and qualified, any future
batches shall be identified as a Product rather than a Custom Product.”

5.
Facility and Records. Section 3.1 is hereby amended by deleting in subsection
(b) of the third sentence the word “expiration” and replacing it with the word
“certification”.

6.
Term. Section 4.1(b) of the Agreement is hereby deleted in its entirety and
replaced with the following:

“(b) with respect to all other Services under this Agreement, on the later of
(i) June 30, 2018 (ii) the completion of all Services under the last Work Order
executed by the Parties prior to June 30, 2018 (the “Other Products Term”). The
Agreement may be renewed by mutual agreement of the Parties.”
7.
Fees. The second sentence of Section 5.1 of the Agreement is hereby deleted.

8.
Invoices. (a) The second sentence of Section 5.2 of the Agreement shall be
deleted and replaced with the following: “Invoices shall contain a detailed
breakdown of charges per batch, per week, and per lot (except when billing is
based on milestones, in which case such detail shall be provided with the
initial invoice) as set forth in the agreed upon Work Order.”

(a)A new sentence is hereby added to the end of section 5.2 of the Agreement to
read as follows:

“An invoice for 1/3 of the total cost will be due [**] days in advance of the
date set forth on the applicable Work Order under this Agreement. Spark
Therapeutics will be invoiced and pay an additional 1/3 of the total cost of
each Work Order upon completion of Product manufacturing, and the remaining 1/3
upon receipt and acceptance of the Product by Spark Therapeutics; provided that
Spark Therapeutics does not unreasonably delay receipt and acceptance of the
Product when made available by CHOP.”

9.
Financial Audit. The first sentence of Section 5.4 is hereby amended by
replacing the words “[**] years” by “[**] years”.

10.
Remedy. A new sentence is hereby added to the end of Section 9.3 of the
Agreement to read as follows: “The provisions in this section do not apply to
Custom Products. CHOP will guarantee that Custom Products conform to the
specifications set for sterility, endotoxin and mycoplasma, and will replace
products not conforming to these specifications as defined herein, unless other
specifications are specifically agreed to in the applicable Work Order.”

11.
Certificate of Analysis. A new Section 9.5 is hereby added to the Agreement
immediately following Section 9.4 which shall read in its entirety as set forth
below:

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“Certificate of Analysis. Release and stability specifications will be set as
per written CHOP policy entitled "AAV Investigational Drug products: Release and
Stability Specifications". Assays not performed by CHOP, will not be included in
the Certificate of Analysis issued by CHOP.”
12.
Exhibit B. Exhibit B to the Agreement is hereby deleted in its entirety and
replaced with Exhibit B attached hereto.

13.
Exhibit C. Exhibit C, Form of Work Order, is hereby deleted in its entirety and
replaced with Exhibit C attached hereto.

14.
Counterparts. This Amendment may be executed in counterparts, each of which
shall be deemed to be an original, and all of such counterparts shall together
constitute one and the same agreement.

15.
Entire Agreement. There are no other agreements or understandings, written or
oral, between the parties regarding the Amendment

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IN WITNESS WHEREOF, CHOP and Spark Therapeutics have caused this Amendment to be
executed as of the Effective Date.

Spark Therapeutics, Inc.                    The Children’s Hospital of
Philadelphia

By:_/s/ Joseph W. La Barge______________            By:_/s/ Mary Tomlinson_____
Name: Joseph W. La Barge                    Name: Mary Tomlinson
Title:_General Counsel                        Title:_ SVP Research
Administration
Date:_____3/9/2016______________________            Date:____3/9/16_________________

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Exhibit B

WORK ORDER

Lot Start Date:

Budget

[VECTOR]
 
 
 
 
Cost/batch
# Batches
Total Cost
Materials
 
 
 
QC testing
 
 
 
 
Cost/week
# Weeks
Total Cost
Labor
 
 
 
Maintenance
 
 
 
 
Cost/lot
# Lots
Total Cost
Materials
 
 
 
QC testing
 
 
 
Fill & Finish
 
 
 
Insurance
 
 
 
CMC Support
 
 
 
Shipping & Handling
 
 
 
Other
 
 
 
Stability1
 
 
 
Subtotal
 
 
 
Hospital Surcharge (Industry Rate)
 
 
 
Total
 
 
 

1.
Each Work Order shall specify which party shall be responsible for holding the
stability samples and owning the stability protocol of the corresponding lot.

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Exhibit C
FORM OF WORK ORDER

WORK ORDER # [___]

Pursuant to Section 2.1 of the Master Research Services Agreement dated October
14, 2013, as amended, by and between Spark Therapeutics, Inc. (f/k/a/ AAVenue
Therapeutics, LLC) and The Children’s Hospital of Philadelphia (“CHOP”) and in
consideration of the mutual promises contained therein and for other good and
valuable consideration the receipt and adequacy of which each of the parties
does hereby acknowledge, the parties hereby agree to this new Work Order
entitled “______________________________________”, which is designated Work
Order - #___.
This Work Order No. [__] includes Attachment 1 setting for the scope, budget and
other costs associated with certain work being performed by CHOP related to the
___________________________.

SPARK THERAPEUTICS, INC.
THE CHILDREN’S HOSPITAL OF PHILADELPHIA

By:__________________________            By:__________________________
Name: _______________________            Name: _______________________
Title: ________________________            Title: ________________________
Date: ________________________            Date: ________________________

PO Number:    _____________________