Exhibit 10.38

Addendum #5 To The Lease Dated on or about July 1, 2011

By and Between Condiotti Enterprises, Inc. (“Lessor”) And

Ultragenyx Pharmaceutical Inc. (“Lessee”)

Lessor and Lessee are parties to that certain Lakepoint Business Park Standard
Lease dated on or about July 1, 2011 and amended by that certain Addendum One
dated on or about July 1, 2011, that certain Addendum Two dated on or about
March 7, 2012, and that certain Addendum #3 effective February 12, 2014,
pursuant to which Lessee leases from Lessor the entire space on the first and
second floors of the building located at 60 Leveroni Court, Novato, California
and Addendum #4 effective March 13, 2015 which adds the entire space at 52
Leveroni Court and which together constitute the Lease.

Now, therefore, the parties do wish to amend the Lease further as follows:

94. Subject to the Terms of the Lease, there shall be added to the existing
Premises occupied by Lessee (43,517sf±comprising the entire Building located at
60 Leveroni Court, and 20,343±sf comprising the entire Building located at 52
Leveroni Court, both in Novato, California) (the “Existing Space”) approximately
10,408sf±, comprising the first floor of the Building located at 68 Leveroni
Court. The Existing Space, the 52 Expansion Space and this additional space at
68 Leveroni Court (the “68 Expansion Space”) are collectively referred to herein
as the “Entire Premises”.

95. The Term for the 68 Expansion Space shall commence on May 1, 2015 and expire
on April 30, 2019, unless extended in accordance with the Terms of the Lease.

96. The Anniversary Date for the Entire Premises shall be May 1st for the
purposes of the annual Base Monthly Rent increase, subject to the Terms of the
Lease.

97. Effective May 1, 2015 Initial Base Monthly Rent for the 52 Expansion Space
shall be $14,571.20.

98. Thereafter, Base Monthly Rent for the Entire Premises shall be increased
annually, effective May 1 of each year, in accordance with the Terms of the
Lease.

99. Lessee shall take the 68 Expansion Space in “As-Is” condition.

100. Lessee shall not incur Base Monthly Rent for the period of early access,
which shall commence upon full execution of this Addendum #5 and extend through
April 30, 2015, but Lessee shall remain responsible for the prompt and timely
payment of all utilities and other expenses incurred in connection with the
early access to the 68 Expansion Space including Operating Expenses as detailed
in Section 9 of the Lease.

101. Lessor shall deliver the 68 Expansion Space with all Building Systems in
good working condition.

102. Lessee shall have exclusive use of up to 38 unreserved and unassigned
parking spaces on the property.

103. This 68 Expansion Space shall be eligible for the Options to Extend as
included in Section 51 of the Lease and subject to those same Terms.

104. Each party to this Addendum #5 represents  and agrees that no commissions
or fees of any kind have been incurred in relation to or as a result of this
Addendum  #5 and, further, any such commission  or fee so related shall be borne
by the party incurring it.

105. Except as expressly modified by this Addendum #5 the Lease shall remain in
full force and effect.

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Agreed to this 7th day of April, 2015.

 

Lessee

 

Lessor

 

 

 

/s/ Emil Kakkis

 

/s/ Jan Warz

 

 

 

Emil Kakkis, President and CEO

 

Jan Warz, Vice President and COO

 

 

 

Ultragenyx Pharmaceutical Inc.

 

Condiotti Enterprises, Inc.

 

 

 

 

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