Exhibit 10.5


 


Constellation Alpha Capital Corp.


3 Allied Drive, Suite 303


Dedham, MA 02026


 


August 31, 2015


 


Centripetal, LLC


3 Allied Drive, Suite 303


Dedham, MA 02026


 


		RE:	        Securities
                                         Purchase Agreement



 


Ladies and Gentlemen:


 


We are pleased to accept
the offer you (the “Subscriber”) have made to purchase an aggregate of 1,437,500 ordinary shares (the “Shares”)
of no par value per share (the “Ordinary Shares”), up to 187,500 of which Shares are subject to complete
or partial forfeiture (the “forfeiture”) by you if the underwriters of the initial public offering (“IPO”)
of Constellation Alpha Capital Corp., a British Virgin Islands company (the “Company”) do not fully exercise
their over-allotment option (the “Over-allotment Option”). The terms on which the Company is willing to sell
the Shares to the Subscriber, and the Company and the Subscriber’s agreements regarding such Shares, are as follows:


 


1.            Purchase
of Shares. For the aggregate sum of $25,000 (the “Purchase Price”), which the Company acknowledges receiving
in cash, the Company hereby sells and issues to the Subscriber, and the Subscriber hereby purchases from the Company the Shares,
for a purchase price of approximately $0.017 per Share, subject to forfeiture by the Subscriber, on the terms and subject to the
conditions set forth in this Agreement. Concurrently with the Subscriber’s execution of this Agreement, the Company is delivering
to the Subscriber certificate(s) registered in the Subscriber’s name representing the Shares, receipt of which the Subscriber
hereby acknowledges.


 


2.            Representations,
Warranties and Agreements.


 


2.1       Subscriber’s
Representations, Warranties and Agreements. To induce the Company to issue the Shares to the Subscriber, the Subscriber hereby
represents and warrants to the Company and agrees with the Company as follows:


 


2.1.1.   No Government
Recommendation or Approval. The Subscriber understands that no United States federal or state agency or similar agency of any other
country has passed upon or made any recommendation or endorsement of the offering of the Shares.


 


2.1.2.   No Conflicts.
The execution, delivery and performance of this Agreement and the consummation by the Subscriber of the transactions contemplated
hereby do not violate, conflict with or constitute a default under (i) the formation and governing documents of the Subscriber,
(ii) any agreement, indenture or instrument to which the Subscriber is a party, (iii) any law, statute, rule or regulation to which
the Subscriber is subject, or (iv) any agreement, order, judgment or decree to which the Subscriber is subject.


 




     


     


    

 


2.1.3.   Organization and
Authority. The Subscriber is a Delaware limited liability company, validly existing and in good standing under the laws of Delaware
and possesses all requisite power and authority necessary to carry out the transactions contemplated by this Agreement. Upon execution
and delivery by you, this Agreement is a legal, valid and binding agreement of Subscriber, enforceable against Subscriber in accordance
with its terms, except as such enforceability may be limited by applicable bankruptcy, insolvency, fraudulent conveyance or similar
laws affecting the enforcement of creditors’ rights generally and subject to general principles of equity (regardless of
whether enforcement is sought in a proceeding at law or in equity).


 


2.1.4.   Experience, Financial
Capability and Suitability. Subscriber is: (i) sophisticated in financial matters and is able to evaluate the risks and benefits
of the investment in the Shares and (ii) able to bear the economic risk of its investment in the Shares for an indefinite period
of time because the Shares have not been registered under the Securities Act (as defined below) and therefore cannot be resold
unless subsequently registered under the Securities Act or an exemption from such registration is available. Subscriber must bear
the economic risk of this investment until the Shares are sold pursuant to: (x) an effective registration statement under the Securities
Act or (y) an exemption from registration available with respect to such sale. Subscriber is able to bear the economic risks of
an investment in the Shares and to afford a complete loss of Subscriber’s investment in the Shares.


 


2.1.5.   Access to Information;
Independent Investigation. Prior to the execution of this Agreement, the Subscriber has had the opportunity to ask questions of
and receive answers from representatives of the Company concerning an investment in the Company, as well as the finances, operations,
business and prospects of the Company, and the opportunity to obtain additional information to verify the accuracy of all information
so obtained. In determining whether to make this investment, Subscriber has relied solely on Subscriber’s own knowledge and
understanding of the Company and its business based upon Subscriber’s own due diligence investigation and the information
furnished pursuant to this paragraph. Subscriber understands that no person has been authorized to give any information or to make
any representations which were not furnished pursuant to this Section 2 and Subscriber has not relied on any other representations
or information in making its investment decision, whether written or oral, relating to the Company, its operations or its prospects.


 


2.1.6.   Regulation D Offering.
Subscriber represents that it is an “accredited investor” as such term is defined in Rule 501(a) of Regulation D under
the Securities Act of 1933, as amended (the “Securities Act”) and acknowledges the sale contemplated hereby is being
made in reliance on a private placement exemption to “accredited investors” or similar exemptions under federal and
state law.


 


2.1.7.   Investment Purposes.
The Subscriber is purchasing the Shares solely for investment purposes, for the Subscriber’s own account and not for the
account or benefit of any other person, and not with a view towards the distribution or dissemination thereof. The Subscriber did
not enter into this Agreement as a result of any general solicitation or general advertising within the meaning of Rule 502 of
Regulation D under the Securities Act.


 




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2.1.8.   Restrictions on
Transfer; Shell Company. Subscriber understands the Shares are being offered in a transaction not involving a public offering within
the meaning of the Securities Act. Subscriber understands the Shares will be “restricted securities” as defined in
Rule 144(a)(3) under the Securities Act and Subscriber understands that the certificate representing the Shares will contain a
legend in respect of such restrictions. If in the future the Subscriber decides to offer, resell, pledge or otherwise transfer
the Shares, such Shares may be offered, resold, pledged or otherwise transferred only pursuant to: (i) an effective registration
statement under the Securities Act, or (ii) an available exemption from registration. Subscriber agrees that if any transfer of
its Shares or any interest therein is proposed to be made, as a condition precedent to any such transfer, Subscriber may be required
to deliver to the Company an opinion of counsel satisfactory to the Company. Absent registration or an exemption, the Subscriber
agrees not to resell the Shares. Subscriber further acknowledges that because the Company is a shell company, Rule 144 may not
be available to the Subscriber for the resale of the Shares until one year following consummation of the initial business combination
of the Company, despite technical compliance with the certain requirements of Rule 144 and the release or waiver of any contractual
transfer restrictions.


 


2.1.9.  No Governmental
Consents. No governmental, administrative or other third party consents or approvals are required, necessary or appropriate on
the part of Subscriber in connection with the transactions contemplated by this Agreement.


 


2.2       Company’s
Representations, Warranties and Agreements. To induce the Subscriber to purchase the Shares, the Company hereby represents
and warrants to the Subscriber and agrees with the Subscriber as follows:


 


2.2.1 Organization
and Corporate Power. The Company is a corporation duly incorporated, validly existing and in good standing under the laws of
the British Virgin Islands and is qualified to do business in every jurisdiction in which the failure to so qualify would reasonably
be expected to have a material adverse effect on the financial condition, operating results or assets of the Company. The Company
possesses all requisite corporate power and authority necessary to carry out the transactions contemplated by this Agreement.


 


2.2.2. No
Conflicts. The execution, delivery and performance of this Agreement and the consummation by the Company of the transactions
contemplated hereby do not violate, conflict with or constitute a default under (i) the memorandum and articles of association
of the Company, (ii) any agreement, indenture or instrument to which the Company is a party or (iii) any law, statute, rule
or regulation to which the Company is subject, or any agreement, order, judgment or decree to which the Company is subject.


 


2.2.3. Title
to Securities. Upon issuance in accordance with, and payment pursuant to, the terms hereof, the Shares will be duly and validly
issued, fully paid and nonassessable. Upon issuance in accordance with, and payment pursuant to, the terms hereof the Subscriber
will have or receive good title to the Shares, free and clear of all liens, claims and encumbrances of any kind, other than (a)
transfer restrictions hereunder and under the other agreements contemplated hereby, (b) transfer restrictions under federal and
state securities laws, and (c) liens, claims or encumbrances imposed due to the actions of the Subscriber.


 




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3.            Forfeiture
of Shares.


 


3.1.      Partial
or No Exercise of the Over-allotment Option. In the event the Over-allotment Option is not exercised in full, the Subscriber
shall forfeit any and all rights to up to 187,500 Shares (based upon the percentage of the Over-allotment Option not exercised)
such that immediately following such forfeiture, the Subscriber and all other initial shareholders prior to the IPO will own an
aggregate number of Ordinary Shares (not including Ordinary Shares issuable upon exercise of any warrants or any shares purchased
by Subscribers in the Company’s IPO or in the aftermarket) equal to 20% of the issued and outstanding Ordinary Shares of
the Company immediately following the IPO.


 


3.2.       Termination
of Rights as Shareholder. If any of the Shares are forfeited by the Subscriber in accordance with this Section 3, then after
such time, the Subscriber (or successor in interest), shall no longer have any rights as a holder of such Shares, and the Company
shall take such action as is appropriate to cancel such Shares which may include by way of the compulsory redemption and cancellation
of such Shares for nil consideration. In addition, the Subscriber hereby irrevocably grants the Company a limited power of attorney
for the purpose of effectuating the foregoing and agrees to take any and all action reasonably requested by the Company necessary
to effect any adjustment in this Section 3 (including any such redemption as is referred to herein above).


 


4.            Waiver
of Liquidation Distributions; Redemption Rights. In connection with the Shares purchased pursuant to this Agreement and any
other Company securities purchased on a private placement basis, the Subscriber hereby waives any and all right, title, interest
or claim of any kind in or to any distributions by the Company from the Trust Account (as such term is defined in the Investment
Management Trust Agreement to be entered by and between the Company and the trustee thereunder), in the event of a liquidation
of the Company upon the Company’s failure to timely complete a business combination. For purposes of clarity, in the event
any Subscriber purchases Ordinary Shares in the IPO or in the aftermarket, any additional shares so purchased shall be eligible
to receive their pro rata portion of any liquidating distributions by the Company. However, in no event will the Subscriber have
the right to redeem any Shares, or any Ordinary Shares purchased in the IPO or in the aftermarket, for funds held in the Trust
Account upon the successful completion of a business combination.


 


5.            Restrictions
on Transfer.


 


5.1.      Securities
Law Restrictions. In addition to any restrictions to be contained in the Letter Agreement (as defined in Section 5.5 below),
the Subscriber agrees not to sell, transfer, pledge, hypothecate or otherwise dispose of all or any part of the Shares unless,
prior thereto (a) a registration statement on the appropriate form under the Securities Act and applicable state securities laws
with respect to the Shares proposed to be transferred shall then be effective or (b) the Company shall have received an opinion
from counsel reasonably satisfactory to the Company, that such registration is not required because such transaction is exempt
from registration under the Securities Act and the rules promulgated by the Securities and Exchange Commission thereunder and with
all applicable state securities laws.


 


5.2       Restrictive
Legends. All certificates representing the Shares shall have endorsed thereon legends substantially as follows:


 




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“THESE SECURITIES (i) HAVE
NOT BEEN REGISTERED UNDER THE UNITED STATES SECURITIES ACT OF 1933, AS AMENDED (THE “SECURITIES ACT”), AND THESE SECURITIES
MAY NOT BE OFFERED, SOLD, PLEDGED OR OTHERWISE TRANSFERRED EXCEPT (A) PURSUANT TO AN EFFECTIVE REGISTRATION STATEMENT FILED UNDER
THE SECURITIES ACT, (B) PURSUANT TO AN EXEMPTION FROM REGISTRATION PROVIDED BY RULE 144 UNDER THE SECURITIES ACT (IF AVAILABLE)
OR (C) PURSUANT TO ANY OTHER EXEMPTION FROM THE REGISTRATION REQUIREMENTS OF THE SECURITIES ACT, IN EACH CASE IN ACCORDANCE WITH
ANY APPLICABLE SECURITIES LAWS OF ANY STATE OF THE UNITED STATES OR ANY OTHER JURISDICTION. HEDGING TRANSACTIONS INVOLVING THESE
SECURITIES MAY NOT BE CONDUCTED UNLESS IN COMPLIANCE WITH THE SECURITIES ACT.”


 


“THE SECURITIES REPRESENTED
BY THIS CERTIFICATE ARE SUBJECT TO A LETTER AGREEMENT AND MAY NOT BE OFFERED, SOLD, TRANSFERRED, PLEDGED OR OTHERWISE DISPOSED
DURING THE TERM OF THE LETTER AGREEMENT, EXCEPT IN ACCORDANCE WITH THE TERMS THEREOF.”


 


5.3.       Additional
Shares or Substituted Securities. In the event of the declaration of a stock dividend, the declaration of an extraordinary
dividend payable in a form other than stock, a spin-off, a stock split, an adjustment in conversion ratio, a recapitalization or
a similar transaction affecting the Company’s outstanding capital stock without receipt of consideration, any new, substituted
or additional securities or other property which are by reason of such transaction distributed with respect to any Shares subject
to this Section 5 or into which such Shares thereby become convertible shall immediately be subject to this Section 5 and Section
3. Appropriate adjustments to reflect the distribution of such securities or property shall be made to the number and/or class
of Shares subject to this Section 5 and Section 3.


 


5.4        Lock-up.
The Subscriber acknowledges that the Shares will be subject to lock-up provisions (the “Lock-up”) contained
in a Letter Agreement, to be entered into prior to the date of the preliminary prospectus in connection with the IPO between the
Subscriber and the Company (the “Letter Agreement”). Pursuant to the Letter Agreement, the Subscriber shall
not sell, transfer, pledge, hypothecate or otherwise dispose of any or all of 50% of its Shares until the earlier of one year after
the date of the consummation of the Company’s initial business combination (the “Consummation Date”) and
the date on which the closing price of the Ordinary Shares exceeds $12.50 per share for any 20 trading days within a 30-trading
day period following the Consummation Date (as adjusted for stock splits, stock dividends, reorganizations and recapitalizations).
In addition, the Subscriber shall not sell, transfer, pledge, hypothecate or otherwise dispose of any or all of the remaining 50%
of the Shares until one year after the Consummation Date. Notwithstanding the foregoing, the aforesaid restrictions shall lapse
if, subsequent to the Consummation Date, the Company consummates a subsequent liquidation, merger, stock exchange or other similar
transaction which results in all of the Company’s shareholders having the right to exchange their Ordinary Shares for cash,
securities or other property.


 




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5.5       Registration
Rights. The Subscriber acknowledges that the Shares are being purchased pursuant to an exemption from the registration requirements
of the Securities Act and will become freely tradable only after they are registered pursuant to a Registration Rights Agreement
to be entered into with the Company prior to the closing of the IPO (“Registration Rights Agreement”). The Subscriber
is entitled to make such number of demands that the Company registers the Shares pursuant to the terms and restrictions as set
forth in the Registration Rights Agreement.


 


6.            Other
Agreements.


 


6.1.      Further
Assurances. The Subscriber agrees to execute such further instruments and to take such further action as may reasonably be
necessary to carry out the intent of this Agreement.


 


6.2       No
Obligation as to Employment. The Company is not by reason of this Agreement obligated to employ, or continue to employ,
the Subscriber in any capacity.


 


6.3.      Notices.
All notices, requests, consents and other communications hereunder shall be in writing, shall be addressed to the receiving party’s
address set forth on the first page of this Agreement or to such other address as a party may designate by notice hereunder, and
shall be either (a) delivered by hand, (b) sent by overnight courier, or (c) sent by certified mail, return receipt requested,
postage prepaid. All notices, requests, consents and other communications hereunder shall be deemed to have been given either (i)
if by hand, at the time of the delivery thereof to the receiving party at the address of such party set forth above, (ii) if sent
by overnight courier, on the next business day following the day such notice is delivered to the courier service, or (iii) if sent
by certified mail, on the (5th) business day following the day such mailing is made.


 


6.4.      Entire
Agreement. This Agreement, together with the Letter Agreement, substantially in the form to be filed as an exhibit to the Company’s
registration statement on Form S-1, embodies the entire agreement and understanding between the Subscriber and the Company with
respect to the subject matter hereof and supersedes all prior oral or written agreements and understandings relating to the subject
matter hereof. No statement, representation, warranty, covenant or agreement of any kind not expressly set forth in this Agreement
shall affect, or be used to interpret, change or restrict, the express terms and provisions of this Agreement.


 


6.5.      Modifications
and Amendments. The terms and provisions of this Agreement may be modified or amended only by written agreement executed by
all parties hereto.


 


6.6.      Waivers
and Consents. The terms and provisions of this Agreement may be waived, or consent for the departure therefrom granted, only
by written document executed by the party entitled to the benefits of such terms or provisions. No such waiver or consent shall
be deemed to be or shall constitute a waiver or consent with respect to any other terms or provisions of this Agreement, whether
or not similar. Each such waiver or consent shall be effective only in the specific instance and for the purpose for which it was
given, and shall not constitute a continuing waiver or consent.


 




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6.7.      Assignment.
The rights and obligations under this Agreement may not be assigned by either party hereto without the prior written consent of
the other party.


 


6.8.      Benefit.
All statements, representations, warranties, covenants and agreements in this Agreement shall be binding on the parties hereto
and shall inure to the benefit of the respective successors and permitted assigns of each party hereto. Nothing in this Agreement
shall be construed to create any rights or obligations except among the parties hereto, and no person or entity shall be regarded
as a third-party beneficiary of this Agreement.


 


6.9.      Governing
Law. This Agreement and the rights and obligations of the parties hereunder shall be construed in accordance with and governed
by the laws of the British Virgin Islands for agreements made and to be wholly performed within such country.


 


6.10.    Severability.
In the event that any court of competent jurisdiction shall determine that any provision, or any portion thereof, contained in
this Agreement shall be unreasonable or unenforceable in any respect, then such provision shall be deemed limited to the extent
that such court deems it reasonable and enforceable, and as so limited shall remain in full force and effect. In the event that
such court shall deem any such provision, or portion thereof, wholly unenforceable, the remaining provisions of this Agreement
shall nevertheless remain in full force and effect.


 


6.11.    No
Waiver of Rights, Powers and Remedies. No failure or delay by a party hereto in exercising any right, power or remedy under
this Agreement, and no course of dealing between the parties hereto, shall operate as a waiver of any such right, power or remedy
of such party. No single or partial exercise of any right, power or remedy under this Agreement by a party hereto, nor any abandonment
or discontinuance of steps to enforce any such right, power or remedy, shall preclude such party from any other or further exercise
thereof or the exercise of any other right, power or remedy hereunder. The election of any remedy by a party hereto shall not constitute
a waiver of the right of such party to pursue other available remedies. No notice to or demand on a party not expressly required
under this Agreement shall entitle the party receiving such notice or demand to any other or further notice or demand in similar
or other circumstances or constitute a waiver of the rights of the party giving such notice or demand to any other or further action
in any circumstances without such notice or demand.


 


6.12.     Survival
of Representations and Warranties. All representations and warranties made by the parties hereto in this Agreement or in any
other agreement, certificate or instrument provided for or contemplated hereby, shall survive the execution and delivery hereof
and any investigations made by or on behalf of the parties.


 


6.13.     No
Broker or Finder. Each of the parties hereto represents and warrants to the other that no broker, finder or other financial
consultant has acted on its behalf in connection with this Agreement or the transactions contemplated hereby in such a way as to
create any liability on the other. Each of the parties hereto agrees to indemnify and save the other harmless from any claim or
demand for commission or other compensation by any broker, finder, financial consultant or similar agent claiming to have been
employed by or on behalf of such party and to bear the cost of legal expenses incurred in defending against any such claim.


 




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6.14.    Headings
and Captions. The headings and captions of the various subdivisions of this Agreement are for convenience of reference only
and shall in no way modify or affect the meaning or construction of any of the terms or provisions hereof.


 


6.15.    Counterparts.
This Agreement may be executed in one or more counterparts, all of which when taken together shall be considered one and the same
agreement and shall become effective when counterparts have been signed by each party and delivered to the other party, it being
understood that both parties need not sign the same counterpart.  In the event that any signature is delivered by facsimile
transmission or by e-mail delivery of a “.pdf” format data file, such signature shall create a valid and binding obligation
of the party executing (or on whose behalf such signature is executed) with the same force and effect as if such facsimile or “.pdf”
signature page were an original thereof.


 


7.            Voting
and Tender of Shares. The Subscriber agrees to vote the Shares as well as any Ordinary Shares acquired in the IPO or the aftermarket
in favor of a business combination that the Company negotiates and presents for approval to the Company’s shareholders and
shall not seek redemption with respect to the Shares. Additionally, the Subscriber agrees not to tender any Share in connection
with a tender offer presented to the Company’s shareholders in connection with an initial business combination negotiated
by the Company. 


 


8.            Indemnification.
Each party shall indemnify the other and the underwriter of the IPO against any loss, cost or damages (including reasonable attorney’s
fees and expenses) incurred as a result of such party’s breach of any representation, warranty, covenant or agreement in
this Agreement.


 


[Signature Page Follows]


 




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If the foregoing accurately sets forth our understanding and
agreement, please sign the enclosed copy of this agreement and return it to us.


 


	 	Very truly yours,	 
	 	 	 
	 	CONSTELLATION ALPHA CAPITAL CORP.	 
	 	 	 
	 	By:	    /s/ Peter D. Rudden, Jr.	 


 


	 	Name:   Peter D. Rudden, Jr.	 
	 	Title:   Director	 


 


Accepted and agreed this


August 31, 2015


 


	CENTRIPETAL, LLC	 
	 	 
	By:	      /s/ Peter D. Rudden, Jr.	 
	Name:       Peter D.
    Rudden, Jr.	 
	Title:       Authorized
    Person	 
	 	 	 


 








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