Exhibit 10.5


 


LIFESCI
CAPITAL LLC


250 West
55th Street, 34th Floor


New York,
New York 10019


 


October 7,
2020


 


Petra Acquisition,
Inc.


5 West 21st
Street


New York,
NY 10010


Attn: Andreas
Typaldos


 


Ladies and Gentlemen:


 


This
is to confirm our agreement whereby Petra Acquisition, Inc., a Delaware corporation (“Company”), has requested
LifeSci Capital LLC (“LifeSci”), Ladenburg Thalmann & Co. Inc. (“Ladenburg”), Ingalls
& Snyder LLC (“Ingalls”), and Northland Securities, Inc. (“Northland”), 277 Park Avenue,
26th Floor, New York, NY 10172, (together, the “Advisors” and each an “Advisor”)
to assist it in connection with the Company merging with, acquiring, engaging in a share exchange, recapitalization or reorganization,
purchasing all or substantially all of the assets of, entering into contractual arrangements, or engaging in any other similar
business combination (in each case, a “Business Combination”) with one or more businesses or entities (each
a “Target”) as described in the Company’s Registration Statement on Form S-1 (File No. 333-240175) filed
with the Securities and Exchange Commission (collectively, the “Registration Statement”) in connection with
its initial public offering (“IPO”).


 


	 	1.	Services and Fees.


 


(a)
The Advisors will:

 


	 	(i)	Hold meetings with Company stockholders to discuss the Business
    Combination and the Target’s attributes;


 


	 	(ii)	Introduce the Company to potential investors to purchase the
    Company’s securities in connection with the Business Combination;


 


	 	(iii)	Assist the Company in trying to obtain stockholder approval
    for the Business Combination, including assistance with the Company’s proxy statement or tender offer materials; and


 


	 	(iv)	Assist the Company with any press releases and filings related
    to the Business Combination or the Target.


 


(b)
As compensation for the foregoing services, the Company will pay the Advisors a cash fee equal to, in the aggregate, 4% of the
gross proceeds received by the Company in the IPO (the “Fee”). The Company will allocate 52.5% of the Fee to
LifeSci, 10% of the Fee to Ingalls, 22.5% of the Fee to Ladenburg and 15% of the Fee to Northland. The Fee shall be exclusive
of any finder’s fees which may become payable to the Advisors pursuant to any other agreement between the Advisors and the
Company or the Target.


 


(c)
The Fee shall be payable in cash and is due and payable to the Advisors by wire transfer at the closing of the Business Combination
(“Closing”); provided that the Fee shall not be paid prior to the date that is 90 days from the effective date
of the Registration Statement unless the Financial Industry Regulatory Authority determines that such payment would not be deemed
underwriters’ compensation in connection with the IPO. If a proposed Business Combination is not consummated for any reason,
no Fee shall be due or payable to the Advisors hereunder.


 






     


     


    

 


	 	2.	Expenses.


 


At
the Closing, the Company shall reimburse the Advisors for all reasonable costs and expenses incurred by the Advisors (including
reasonable fees and disbursements of counsel) in connection with the performance of its services hereunder up to a maximum of
$20,000.


 


	 	3.	Company Cooperation.


 


The
Company will provide full cooperation to each Advisor as may be necessary for the efficient performance by the such Advisor of
its obligations hereunder, including, but not limited to, providing to such Advisor and its counsel, on a timely basis, all documents
and information regarding the Company and Target that such Advisor may reasonably request or that are otherwise relevant to the
Advisor’s performance of its obligations hereunder (collectively, the “Information”); making the Company’s
management, auditors, suppliers, customers, consultants and advisors available to such Advisor; and, using commercially reasonable
efforts to provide such Advisor with reasonable access to the management, auditors, suppliers, customers, consultants and advisors
of Target. The Company will promptly notify the Advisors of any change in facts or circumstances or new developments affecting
the Company or Target or that might reasonably be considered material to any Advisor’s engagement hereunder.


 


	 	4.	Representations; Warranties and Covenants.


 


The
Company represents, warrants and covenants to each Advisor that all Information it makes available to any Advisor by or on behalf
of the Company in connection with the performance of its obligations hereunder will not contain any untrue statement of a material
fact or omit to state a material fact necessary in order to make statements made, in light of the circumstances under which they
were made, not misleading as of the date thereof and as of the consummation of the Business Combination.


 


	 	5.	Indemnity.


 


The
Company shall indemnify each Advisor and its affiliates and directors, officers, employees, stockholders, representatives and
agents in accordance with the indemnification provisions set forth in Annex I hereto, all of which are incorporated herein by
reference. 


 


Notwithstanding
the foregoing and Annex 1, each Advisor agrees, if there is no Closing, (i) that it does not have any right, title, interest or
claim of any kind in or to any monies in the Company’s trust account (“Trust Account”) established in
connection with the IPO with respect to the Fee (each, a “Claim”); (ii) to waive any Claim it may have in the
future as a result of, or arising out of, any services provided to the Company hereunder; and (iii) to not seek recourse against
the Trust Account with respect to the Fee.


 


	 	6.	Use of Name and Reports.


 


Without
each Advisor’s prior written consent, neither the Company nor any of its affiliates (nor any director, officer, manager,
partner, member, employee or agent thereof) shall quote or refer to (i) any Advisor’s name or (ii) any advice rendered by
any Advisor to the Company or any communication from any Advisor in connection with performance of their services hereunder, except
as required by applicable federal or state law, regulation or securities exchange rule.


 


	 	7.	Status as Independent Contractor.


 


Each
Advisor shall perform its services as an independent contractor and not as an employee of the Company or affiliate thereof. It
is expressly understood and agreed to by the parties that no Advisor shall have authority to act for, represent or bind the Company
or any affiliate thereof in any manner, except as may be expressly agreed to by the Company in writing. In rendering such services,
the Advisors will be acting solely pursuant to a contractual relationship on an arm’s-length basis. This Agreement is not
intended to create a fiduciary relationship between the parties and neither the Advisors nor any of the Advisors’ officers,
directors or personnel will owe any fiduciary duty to the Company or any other person in connection with any of the matters contemplated
by this Agreement.


 






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	 	8.	Potential Conflicts.


 


The
Company acknowledges that the Advisors are full-service securities firms engaged in securities trading and brokerage activities
and providing investment banking and advisory services from which conflicting interests may arise. In the ordinary course of business,
each Advisor and its affiliates may at any time hold long or short positions, and may trade or otherwise effect transactions,
for their own account or the accounts of customers, in debt or equity securities of the Company, its affiliates or other entities
that may be involved in the transactions contemplated hereby. Nothing in this Agreement shall be construed to limit or restrict
any Advisor or any of its affiliates in conducting such business.


 


	 	9.	Entire Agreement.


 


This
Agreement constitutes the entire understanding between the parties with respect to the subject matter hereof and supersedes all
prior agreements and understandings, oral or written, with respect thereto. This Agreement may not be modified or terminated orally
or in any manner other than by an agreement in writing signed by the parties hereto.


 


	 	10.	Notices.


 


Any
notices required or permitted to be given hereunder shall be in writing and shall be deemed given when mailed by certified mail
or private courier service, return receipt requested, addressed to each party at its respective addresses set forth above, or
such other address as may be given by a party in a notice given pursuant to this Section.


 


	 	11.	Successors and Assigns.


 


This
Agreement may not be assigned by either party without the written consent of the other. This Agreement shall be binding upon and
shall inure to the benefit of the parties hereto and, except where prohibited, to their successors and assigns.


 


	 	12.	Non-Exclusivity.


 


Nothing
herein shall be deemed to restrict or prohibit the engagement by the Company of other consultants providing the same or similar
services or the payment by the Company of fees to such parties. The Company’s engagement of any other consultant(s) shall
not affect the Advisors’ right to receive the Fee and reimbursement of expenses pursuant to this Agreement.


 


	 	13.	Applicable Law; Venue.


 


This
Agreement shall be construed and enforced in accordance with the laws of the State of New York without giving effect to conflict
of laws.


 


In
the event of any dispute under this Agreement, then and in such event, each party hereto agrees that the dispute shall either
be (i) resolved through final and binding arbitration in accordance with the International Arbitration Rules of the American Arbitration
Association (“AAA”) or (ii) brought and enforced in the courts of the State of New York, County of New York
under the accelerated adjudication procedures of the Commercial Division, or the United States District Court for the Southern
District of New York, in each event at the discretion of the party initiating the dispute. Once a party files a dispute (if arbitration,
by sending JAMS a Demand for Arbitration) with one of the above forums, the parties agree that all issues regarding such dispute
or this Agreement must be resolved before such forum rather than seeking to resolve it through another alternative forum set forth
above.


 


In
the event the dispute is brought before the AAA, the arbitration shall be brought before the AAA International Center for Dispute
Resolution’s offices in New York City, New York, will be conducted in English and will be decided by a panel of three arbitrators
selected from the AAA Commercial Disputes Panel. Each of the parties agrees that the decision and/or award made by the arbitrators
shall be final and enforceable by any court having jurisdiction over the party from whom enforcement is sought. Furthermore, the
parties to any such arbitration shall be entitled to make one motion for summary judgment within 60 days of the commencement of
the arbitration, which shall be decided by the arbitrator[s] prior to the commencement of the hearings. 


 




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In
the event the dispute is brought by a party in the courts of the State of New York or the United States District Court for the
Southern District of New York, each party irrevocably submits to such jurisdiction, which jurisdiction shall be exclusive. Each
party hereby waives any objection to such exclusive jurisdiction and that such courts represent an inconvenient forum. Any such
process or summons to be served upon a party may be served by transmitting a copy thereof by registered or certified mail, postage
prepaid, addressed to such party at the address set forth at the beginning of this Agreement. Such mailing shall be deemed personal
service and shall be legal and binding upon the party being served in any action, proceeding or claim. The parties agree that
the prevailing party(ies) in any such action shall be entitled to recover from the other party(ies) all of its reasonable attorneys’
fees and expenses relating to such action or proceeding and/or incurred in connection with the preparation therefor.


 


	 	14.	Counterparts.


 


This
Agreement may be executed in several original or facsimile counterparts, each one of which shall constitute an original, and together
shall constitute but one instrument. 


 


If
the foregoing correctly sets forth the understanding between each Advisor and the Company with respect to the foregoing, please
so indicate your agreement by signing in the place provided below, at which time this letter shall become a binding contract.


 


[signature
page follows]


 




    4


     


    

 


	 	LIFESCI CAPITAL LLC
	 	 	 
	 	By:	/s/ David Dobkin 
	 	Name: 	David Dobkin
	 	Title:	Managing Director
	 	 

        LADENBURG THALMANN &
        CO. INC.

	 	 	 
	 	By:	/s/Jeffrey Caliva 
	 	Name: 	Jeffrey Caliva
	 	Title:	Vice President
	 	 

        NORTHLAND SECURITIES,
        INC.

	 	 	 
	 	By:	/s/ Carl Goltermann 
	 	Name: 	Carl Golterman
	 	Title:	Vice President
	 	 

        INGALLS & SNYDER
        LLC

	 	 	 
	 	By:	/s/ Michael Coyne 
	 	Name: 	Michael Coyne
	 	Title:	Senior Vice President


 


	AGREED AND ACCEPTED BY:	 
	 	 
	PETRA ACQUISITION, INC.	 
	 	 	 
	By:	/s/ Andreas Typaldos	 
	Name: 	Andreas Typaldos	 
	Title: 	Chief Executive Officer	 


 


{Signature Page to Business Combination Marketing Agreement}


 




    5


     


    

 


ANNEX I


 


Indemnification


 


In
connection with the Company’s engagement of LifeSci Capital LLC, Ingalls & Snyder LLc, Northland Securities, Inc., and
Ladenburg Thalmann & Co. Inc. (together, the “Advisors” and each an “Advisor”) pursuant
to that certain letter agreement (“Agreement”) of which this Annex forms a part, Petra Acquisition, Inc. (the
“Company”) hereby agrees, subject to the second paragraph of Section 4 of the Agreement, to indemnify and hold
harmless each Advisor and each of its affiliates and its respective directors, officers, stockholders, agents and employees of
any of the foregoing (collectively the “Indemnified Persons”), from and against any and all claims, actions,
suits, proceedings (including those of stockholders), damages, liabilities and expenses incurred by any of them (including the
reasonable fees and expenses of counsel), as incurred, (collectively a “Claim”), that (A) are related to or
arise out of (i) any actions taken or omitted to be taken (including any untrue statements made or any statements omitted to be
made) by the Company, or (ii) any actions taken or omitted to be taken by any Indemnified Person in connection with the Company’s
engagement of the Advisors, or (B) otherwise relate to or arise out of any Advisor’s activities on the Company’s behalf
under the Advisors’ engagement, and the Company shall reimburse any Indemnified Person for all expenses (including the reasonable
fees and expenses of counsel) as incurred by such Indemnified Person in connection with investigating, preparing or defending
any such claim, action, suit or proceeding, whether or not in connection with pending or threatened litigation in which any Indemnified
Person is a party. The Company will not, however, be responsible for any Claim that is finally judicially determined to have resulted
from the gross negligence or willful misconduct of any person seeking indemnification for such Claim. The Company further agrees
that no Indemnified Person shall have any liability to the Company for or in connection with the Company’s engagement of
the Advisors except for any Claim incurred by the Company as a result of such Indemnified Person’s gross negligence or willful
misconduct.


 


The
Company further agrees that it will not, without the prior written consent of each Advisor, settle, compromise or consent to the
entry of any judgment in any pending or threatened Claim in respect of which indemnification may be sought hereunder (whether
or not any Indemnified Person is an actual or potential party to such Claim), unless such settlement, compromise or consent includes
an unconditional, irrevocable release of each Indemnified Person from any and all liability arising out of such Claim.


 


Promptly
upon receipt by an Indemnified Person of notice of any complaint or the assertion or institution of any Claim with respect to
which indemnification is being sought hereunder, such Indemnified Person shall notify the Company in writing of such complaint
or of such assertion or institution but failure to so notify the Company shall not relieve the Company from any obligation it
may have hereunder, except and only to the extent such failure results in the forfeiture by the Company of substantial rights
and defenses. If the Company so elects or is requested by such Indemnified Person, the Company will assume the defense of such
Claim, including the employment of counsel reasonably satisfactory to such Indemnified Person and the payment of the fees and
expenses of such counsel. In the event, however, that legal counsel to such Indemnified Person reasonably determines that having
common counsel would present such counsel with a conflict of interest or if the defendant in, or target of, any such Claim, includes
an Indemnified Person and the Company, and legal counsel to such Indemnified Person reasonably concludes that there may be legal
defenses available to it or other Indemnified Persons different from or in addition to those available to the Company, then such
Indemnified Person may employ its own separate counsel to represent or defend him, her or it in any such Claim and the Company
shall pay the reasonable fees and expenses of such counsel. Notwithstanding anything herein to the contrary, if the Company fails
timely or diligently to defend, contest, or otherwise protect against any Claim, the relevant Indemnified Party shall have the
right, but not the obligation, to defend, contest, compromise, settle, assert crossclaims, or counterclaims or otherwise protect
against the same, and shall be fully indemnified by the Company therefor, including without limitation, for the reasonable fees
and expenses of its counsel and all amounts paid as a result of such Claim or the compromise or settlement thereof.


 


In
addition, with respect to any Claim in which the Company assumes the defense, the Indemnified Person shall have the right to participate
in such Claim and to retain his, her or its own counsel therefor at his, her or its own expense.


 






     


     


    

 


The
Company agrees that if any indemnity sought by an Indemnified Person hereunder is held by a court to be unavailable for any reason
then (whether or not any Advisor is an Indemnified Person), the Company and the Advisors shall contribute to the Claim for which
such indemnity is held unavailable in such proportion as is appropriate to reflect the relative benefits to the Company, on the
one hand, and such Advisors on the other, in connection with such Advisors’ engagement referred to above, subject to the
limitation that in no event shall the amount of any such Advisor’s contribution to such Claim exceed the amount of fees
actually received by such Advisor from the Company pursuant to such Advisor’s engagement. The Company hereby agrees that
the relative benefits to the Company, on the one hand, and each Advisor on the other, with respect to such Advisor’s engagement
shall be deemed to be in the same proportion as (a) the total value paid or proposed to be paid or received by the Company or
its stockholders as the case may be, pursuant to the transaction (whether or not consummated) for which the Advisors are engaged
to render services bears to (b) the fee paid or proposed to be paid to such Advisor in connection with such engagement.


 


The
Company’s indemnity, reimbursement and contribution obligations under this Agreement (a) shall be in addition to, and shall
in no way limit or otherwise adversely affect any rights that any Indemnified Party may have at law or at equity and (b) shall
be effective whether or not the Company is at fault in any way.