THIS
NOTE AND THE SECURITIES ISSUABLE UPON CONVERSION HEREOF HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED
(THE “SECURITIES ACT”), AND HAVE BEEN ACQUIRED FOR INVESTMENT AND NOT WITH A VIEW TO, OR IN CONNECTION WITH, THE SALE
OR DISTRIBUTION THEREOF. NO SUCH TRANSFER MAY BE EFFECTED WITHOUT AN EFFECTIVE REGISTRATION STATEMENT RELATED THERETO OR AN OPINION
OF COUNSEL IN A FORM SATISFACTORY TO THE COMPANY THAT SUCH REGISTRATION IS NOT REQUIRED UNDER THE SECURITIES ACT.


 


MARINA
BIOTECH, INC.


 


CONVERTIBLE
PROMISSORY NOTE


 


	US$500,000	November
    22, 2017


 


FOR
VALUE RECEIVED, MARINA BIOTECH, INC., a corporation duly incorporated under the laws of the State of Delaware (the “Company”),
hereby promises to pay to River Charitable Remainder Unit Trust, FBO Isaac Blech, July 20, 1987, Isaac Blech Trustee, or
its permissible assigns (the “Holder”) the principal sum of $500,000.00, together with accrued and unpaid interest
thereon, in the manner provided herein. This convertible promissory note (this “Note”) is being issued by the
Company to the original Holder of this Note (the “Original Holder”) pursuant to that certain Note Purchase
Agreement dated as of November 22, 2017 by and between the Company and the Original Holder (the “Purchase Agreement”).
Each capitalized term used, but not defined, in this Note shall have the meaning ascribed to it in the Purchase Agreement.


 


1.
Payment.


 


(a)
Payment. Unless earlier converted as provided
herein, all amounts outstanding and unpaid under this Note shall be due and payable on the earliest to occur of: (i) at the Company’s
election or on demand by the Holder at any time on or after March 31, 2018 or (ii) on demand by the Holder at any time following
an Event of Default (the earliest to occur of clauses (i) or (ii) being referred to herein as the “Maturity Date”).
The Company waives demand, presentment, diligence, protest, notice of protest and notice of dishonor with respect to this Note.
All payments will be made in lawful money of the United States of America at the principal office of the Company, or at such other
place as the Holder may from time to time designate in writing to the Company.


 


(b)
Pre-Payment. This Note may be prepaid
at the election of the Company at any time without penalty upon five (5) days prior written notice to the Holder.


 




    	 



     


    


 





2.
Interest. Interest on the unpaid principal amount shall accrue beginning on the issue date set forth above at a rate
equal to eight percent (8%) per annum computed on the basis of the actual number of days elapsed and a year of 365 days from the
date of this Note until the principal amount and all interest accrued thereon are paid or converted as provided in Section 3 hereof;
provided, that if the Company does not consummate the Qualified Financing on or before December 15, 2017 (which deadline
may be extended by fifteen (15) days upon mutual agreement between the Company and the placement agent with respect to the Qualified
Financing), then the interest rate shall increase to twenty percent (20%) per annum, with such increased interest rate increasing
by an additional two percent (2%) every month thereafter until this Note is repaid in full (up to a maximum interest rate of thirty
percent (30%)). For purposes of this Note, “Qualified Financing” shall mean any financing transaction involving
the sale by the Company of its equity securities (or securities exercisable for or convertible into the equity securities of the
Company) yielding aggregate gross proceeds to the Company of not less than $5,000,000, which amount shall include not less than
$2,500,000 from one or more strategic investors identified in writing by the Company to the Original Holder prior to the date
of this Note. Except upon the earlier conversion in accordance with Section 3, interest be due and payable on a monthly basis
on the last day of each such month (or the next business day thereafter) beginning on December 31, 2017, which interest shall
be payable, at the option of the Company, either: (x) in cash or (y) in shares of Common Stock (with each share of Common Stock
being valued based on the closing price of the Common Stock on the principal market on which the Common Stock is either traded
or quoted at such time on the date immediately prior to the date on which the applicable interest payment is due and payable hereunder,
or in the event the Common Stock is not then traded or quoted on any principal market, at the price per share equal to the then
current fair market value of the Common Stock, as determined by an independent valuation expert selected jointly by the Company
and the Holder, provided that the Company shall pay any such valuation expenses.


 


3.
Conversion.
The unpaid principal amount of this Note, together with any interest accrued but unpaid thereon, shall automatically be converted
into the securities of the Company to be issued and sold at the closing of the Qualified Financing. Upon the conversion of this
Note pursuant to this Section 3, the Holder shall be entitled to receive such number and amount of the securities of the Company
to be issued upon such conversion equal to the quotient obtained by dividing (i) the unpaid principal amount of this Note (together
with any interest accrued but unpaid thereon) by (ii) the price paid for such securities in the Qualified Financing. The issuance
of securities pursuant to the conversion of this Note will be on, and subject to, the same terms and conditions applicable to
the securities issued in the Qualified Financing.


 


4.
Mechanics of Conversion.


 


(a)
In the event that this Note is converted pursuant
to Section 3, the Holder shall surrender this Note, duly endorsed, to the Company promptly following the closing of the Qualified
Financing, and the Note shall thereupon be canceled. As soon as practicable following surrender of this Note (or a duly executed
affidavit of loss with any indemnity reasonably requested by the Company) and at its expense, the Company will take such steps,
and execute and deliver such agreements, documents and instruments, as may be reasonably necessary to issue and deliver to the
Holder a certificate or certificates representing the securities of the Company to which the Holder is entitled upon such conversion.


 




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(b)
The Holder acknowledges that the conversion of this Note pursuant to Section 3 into the securities of the Company to be
issued in the Qualified Financing may require the Holder’s execution of certain agreements relating to the purchase and
sale of such securities, as well as registration rights, rights of first refusal and co-sale rights, rights of first offer and
voting rights, if any, relating to such securities (collectively, the “Financing Arrangements”). The Holder
agrees to execute all of the Financing Agreements in connection with the Qualified Financing as may be reasonably requested by
the Company.


 


5.
Termination of Rights.
Upon payment in full of this Note, or conversion of this Note in accordance with Section 3, all rights with respect to this Note
shall terminate, whether or not this Note has been surrendered for cancellation.


 


6.
Events of Default. In case an Event of Default shall occur, then upon demand by the Holder (which demand shall not
be required in the case of an Event of Default under Sections 6.1(b) or (c) of the Purchase Agreement), the entire outstanding
principal amount, plus accrued and unpaid interest thereon, of this Note shall become immediately due and payable in the manner
and with the effect provided in the Purchase Agreement and this Note.


 


7.
Transfer; Successors and Assigns. The Holder may not sell, assign, pledge, dispose of or otherwise transfer this Note
or any interest herein without the prior written consent of the Company, which shall not be unreasonably withheld; provided,
however, a Holder that is a partnership, corporation, trust, joint venture, unincorporated organization or other entity
may transfer this Note to any person that owns all (but not less than all) of the issued and outstanding voting securities of
such entity without the prior written consent of the Company. Subject to the preceding sentence, this Note may be transferred
only upon surrender of the original Note (or affidavit of loss with any indemnity reasonably requested by the Company) for registration
of transfer, duly endorsed, or accompanied by a duly executed written instrument of transfer in form satisfactory to the Company.
Thereupon, a new note for the same principal amount and interest will be issued to, and registered in the name of, the transferee.
Interest and principal are payable only to the registered Holder. The terms and conditions of this Note shall inure to the benefit
of and be binding upon the respective successors and assigns of the parties.


 


8.
Security Interest.
The Company’s obligations under this Note are secured pursuant to that certain Security Agreement, dated as of the date
hereof, by the Company in favor of the Holder and that certain Intellectual Property Security Agreement, dated as of the date
hereof, by the Company in favor of the Holder.


 


9.
Governing Law. This Note shall be governed by and construed in accordance with the internal laws of the State of New
York without giving effect to any choice or conflict of law provision or rule (whether of the State of New York or any other jurisdiction).


 


10.
Notices. All notices required or permitted hereunder shall be given in accordance with Section 7.5 of the Purchase
Agreement.


 


11.
Amendments and Waivers. The terms and provisions of this Note may be amended or modified, and any provision hereof
may be waived, only with the written consent of the Company and the Holder.


 


12.
Headings. The headings in this Note are for purposes of reference only, and shall not limit or otherwise affect the
meaning hereof.


 




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13.
Cost of Collection. In the event that Holder is required to take legal or other action to enforce its rights or
obtain collection under this Note, the Company shall pay the Holder hereof reasonable costs of collection, or enforcement of the
terms hereof, including attorneys’ fees.


 


14.
Maximum Payments. Nothing contained herein shall be deemed to establish or require the payment of a rate of interest
or other charges in excess of the maximum permitted by applicable law. In the event that the rate of interest required to be paid
or other charges hereunder exceed the maximum permitted by such law (such as, without limitation, the usury laws), any payments
in excess of such maximum shall be credited against amounts owed by the Company to the Holder and thus refunded to the Company,
or if no further amounts are owed by the Company to the Holder, shall be refunded to the Company. The Company hereby irrevocable
consents to the reformation of this Note, as may be necessary by a court of law, so as to enable enforcement of this Note pursuant
to summary judgment or summary proceeding. For avoidance of doubt, in the event that, for any reason, a finding by a court having
jurisdiction over this Note is made that limits enforceability as a result of excessive interest or other origination or investment
banking fees pursuant to the laws of any jurisdiction, then, such defense shall not be deemed to bar a summary proceeding or summary
judgment on the Note but rather, the Note shall be fully and absolutely enforceable as to all principal and, the court having
jurisdiction shall, after an inquest, have power to reform the Note so as to reduce interest amount to such amount as is immediately
enforceable pursuant to summary judgment or summary proceeding and grant such award, plus any legal or enforcement fees of the
Holder.


 


15.
Construction and Enforcement. Each party acknowledges that its legal counsel participated in the preparation of this
Note and, therefore, stipulates that the rule of construction that ambiguities are to be resolved against the drafting party shall
not be applied in the interpretation of this Note to favor any party against the other. This Note reflects an investment made
by the Holder or its assignor to the Company. This Note is intended as, and shall be deemed an unconditional obligation of
the Company for the payment of money only and, without limitation to any other remedies of the Holder (such as, without limitation,
summary judgment after initiation of a proceeding, or equitable remedies), shall be enforceable against the Company by summary
proceeding pursuant to New York Civil Procedure Law and Rules Section 3213 or any similar rule or statute in the jurisdiction
where enforcement is sought. For purposes of such rule or statute, any other document or agreement to which the Holder and the
Company parties or which the Company delivered to the Holder, which may be convenient or necessary to determine the Holder’s
rights hereunder or the Company’s obligations to the Holder are deemed a part of this Note, whether or not such other document
or agreement was delivered together herewith or was executed apart from this Note.


 


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IN
WITNESS WHEREOF, the Company has caused this Note to be duly executed and delivered.


 


	MARINA
    BIOTECH, INC.	 
	 	 
	By:	/s/
    Vuong Trieu	 
	Name:
    	Vuong
    Trieu	 
	Title:	Executive
    Chairman	 


 


[Signature
Page to Convertible Promissory Note]