Exhibit 10.1

LEASE TERMINATION AGREEMENT

This Lease Termination Agreement (this “Agreement”) is made and entered into as
of May 31, 2017 by and between ASTRAZENECA PHARMACEUTICALS LP, a Delaware
limited partnership (“Landlord”) and CERULEAN PHARMA INC., a Delaware
corporation (“Tenant”).

RECITALS:

A. Landlord and Tenant entered into that certain Lease dated as of July 9, 2015
as amended by First Amendment of Lease dated March 29, 2017 (collectively, the
“Lease”) for certain premises consisting of 12,147 square feet of rentable
office space located on Level 2 of Building D (the “D2 Space”) and 9,092 square
feet of rentable laboratory space located on Level 3 of Building C (the “C3
Space”, and collectively with the D2 Space, the “Premises”) at 35 Gatehouse
Drive, Waltham, Massachusetts; and

B. Tenant desires to terminate the Lease prior to the date set forth in the
Lease, and Landlord is willing to terminate the Lease upon the terms and
conditions set forth in this Agreement; and

C. All capitalized terms used herein but not defined shall have the meanings
assigned to them in the Lease.

AGREEMENTS:

For valuable consideration, the receipt and sufficiency of which are hereby
acknowledged, Landlord and Tenant hereby agree as follows:

1. Termination of Lease; Surrender.

(a) Subject to the condition precedent that Tenant shall have met all
Termination Conditions (defined below) on or prior to May 31, 2017, the Lease
shall be deemed terminated (the “Termination”) effective as of 5:00 p.m. on
May 31, 2017 (the “Termination Date”), as if the Termination Date was the date
originally set forth in the Lease for expiration of the term of the Lease.
Effective as of the Termination Date, Tenant shall have no further rights to use
or occupy the Premises or, except as otherwise expressly set forth in this
Agreement, rights or obligations with respect to the Premises or the Lease.
Landlord acknowledges that Tenant has simultaneously herewith vacated and
surrendered the Premises in the condition required under the Lease including
requirements as to decommissioning of the Premises and Landlord has accepted the
condition of the Premises.

(b) On or prior to May 31, 2017, (i) Tenant shall pay to Landlord a
non-refundable early termination fee of $427,240.68 (the “Termination Fee”) in
immediately available funds and (ii) Tenant shall pay to Landlord all amounts
accrued under the Lease through and including the Termination Date (including
without limitation all Additional Rent) as if the Termination Date set forth
herein was the date originally designated as the Termination Date of the Lease
((i) and (ii) being referred to herein as the “Termination Conditions”).

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(c) In the event Tenant fails to satisfy the Termination Conditions on or before
the Termination Date, the Lease shall, at Landlord’s sole option, remain in full
force and effect, and the Termination Fee shall be applied first to all past-due
Rent existing on June 1, 2017 and second as a credit to Rent next due and owing
until fully expended.

(d) Tenant shall indemnify and hold Landlord harmless from any and all damages,
losses or claims incurred by or asserted against Landlord arising from the
failure of Tenant to (i) timely vacate the Premises on the Termination Date
and/or (ii) surrender the Premises on the Termination Date in the condition
required under the Lease. The foregoing indemnity is in addition to, and not in
lieu of, such other indemnities of Tenant set forth in the Lease.

(e) Landlord shall, within five (5) business days following Tenant’s
satisfaction of the Termination Conditions, return to Tenant the Letter of
Credit held as the Security Deposit.

(f) Except for the surviving obligations detailed in Section 2 of this
Agreement, upon satisfaction of the Termination Conditions, as of the
Termination Date: (i) Tenant releases, acquits and forever discharges Landlord,
and Landlord’s members, officers, directors, agents, employees, shareholders,
successors, assigns and affiliates, of and from any and all claims, liabilities,
demands, causes of action, costs, expenses, attorney’s fees, damages,
indemnities and obligations of every kind and nature, in law, equity, or
otherwise, known and unknown, suspected and unsuspected, disclosed and
undisclosed, arising out of or in any way related to the Lease and (ii) Landlord
releases, acquits and forever discharges Tenant, and Tenant’s members, officers,
directors, agents, employees, shareholders, successors, assigns and affiliates,
of and from any and all claims, liabilities, demands, causes of action, costs,
expenses, attorney’s fees, damages, indemnities and obligations of every kind
and nature, in law, equity, or otherwise, known and unknown, suspected and
unsuspected, disclosed and undisclosed, arising out of or in any way related to
the Lease.

2. Surviving Obligations.

(a) Notwithstanding any provisions herein or in the Lease to the contrary, those
obligations of Tenant which are expressly specified in the Lease to survive the
expiration or earlier termination of the Lease shall survive the Termination of
the Lease.

(b) Notwithstanding any provisions herein or in the Lease to the contrary, those
obligations of Landlord which are expressly specified in the Lease to survive
the expiration or earlier termination of the Lease shall survive the Termination
of the Lease.

(c) Notwithstanding the foregoing provisions 2(a) and 2(b), Landlord shall have
no rights of readjustment with respect to Operating Cost Escalation or Tax
Escalation under the Lease and Tenant shall have no rights of audit with respect
to such Operating Cost Escalation or Tax Escalation under the Lease. In
addition, the Termination Fee shall be deemed to be inclusive of all utility
reimbursements due from Tenant for the month of May, 2017. Meaning and intending
that all payments of utilities, Operating Cost Escalation and Tax Escalation
made through May 31, 2017 shall constitute the total payments for such expenses
required of Tenant, Landlord shall have no right to payment for any underpayment
of such amounts, and Tenant shall have no right to any credit with respect to
any overpayment of such amounts.

 

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(d) Without any obligation to do so and subject to the terms of this section
(d), Tenant may continue to use 35 Gatehouse Drive as its mailing address
through the earlier of its completion of a corporate combination with a third
party or July 28, 2017. During such time, Tenant may collect at the front
security desk on Fridays at 3:00 p.m. any mail addressed to Tenant and delivered
to 35 Gatehouse Drive. Landlord reserves the right to rescind this accommodation
and return any such mail to sender if at any time the volume of mail received is
more than approximately 50 pieces per week and/or if Tenant fails to timely
retrieve mail held. This accommodation by Landlord shall not constitute a right
to use the Premises, nor a lease, license or other occupancy right, and Tenant
hereby waives any claims against Landlord with respect thereto and shall
indemnify Landlord for any claims by third parties with respect thereto.

3. No Brokers. Landlord and Tenant each represents to the other that neither has
dealt with any broker in connection with the early termination of the Lease.
Tenant and Landlord each agree to indemnify and hold the other harmless from and
against any liability, loss, cost, damage or expense, including attorneys’ fees
and court costs resulting from a breach of the above warranty and
representation. The provisions of this paragraph shall survive the termination
of the Lease.

4. Entire Agreement. This Agreement contains all of the agreements of the
parties hereto with respect to the subject matter hereof and no prior agreement,
understanding, or representation pertaining to any such matter shall be
effective for any purpose. No provision of this Agreement may be amended except
by an express agreement in writing signed by the parties hereto or their
respective successors in interest. Except as is expressly modified or amended
herein, the provisions, conditions and terms of the Lease shall remain unchanged
and in full force and effect.

5. Authority. Landlord and Tenant each represents and warrants to the other that
(i) it has full right, power and authority to execute and deliver this
Agreement, (ii) it has obtained all consents, waivers and other authorizations
required under their respective organizational documents and (iii) no
third-party consent is required with respect to such party’s entering into this
Agreement.

6. Counterparts. This Agreement may be executed in multiple counterparts, each
of which shall constitute an original, but all of which shall constitute one
document.

7. Invalidity. If any covenant, condition, or provision herein contained is held
to be invalid by final judgment of any court of competent jurisdiction, the
invalidity of such covenant, condition, or provision shall not in any way affect
any other covenant, condition, or provision herein contained.

8. Bind and Inure; Governing Law. This Agreement shall be binding upon, and
shall inure to the benefit of, Landlord and Tenant, and their respective
successors and assigns. In the event of a conflict between the terms and
provisions of this Agreement and those contained in the Lease, the terms and
provisions of this Agreement shall control. Landlord and Tenant

 

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agree that any legal action commenced to interpret or enforce this Agreement, or
otherwise arising out of this Agreement, shall be maintained in the courts of
the Commonwealth of Massachusetts. This Agreement and the rights and duties of
the parties hereto shall be controlled by and interpreted in accordance with the
laws of the Commonwealth of Massachusetts.

9. Facsimile and PDF Signatures. A facsimile or portable document format (PDF)
signature on this Agreement shall be equivalent to, and have the same force and
effect as, an original signature.

[THE REMAINDER OF THIS DOCUMENT IS INTENTIONALLY LEFT BLANK.]

 

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IN WITNESS WHEREOF, Landlord and Tenant have duly executed this Lease
Termination Agreement as of the day and year first above written.

 

LANDLORD:

 

ASTRAZENECA PHARMACEUTICALS LP,

a Delaware limited partnership

  By:                                          
                                                                                
  Name:                                          
                                                                             
Title:                                          
                                                                             

TENANT:

 

CERULEAN PHARMA INC., a Delaware corporation

  By:                                     
                                         
                                               
Name:                                     
                                                                                
  Title:                                    
                                         
                                         

 

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