Exhibit 10.6

SECOND AMENDMENT TO PARTICIPATION AGREEMENT

This SECOND AMENDMENT TO PARTICIPATION AGREEMENT (“Second Amendment”) is made as
of this 22 day of November, 2013, by and among Cleveland BioLabs, Inc., a
Delaware corporation (“CBL”) and BioProcess Capital Partners, LLC, a management
company of the venture fund BioProcess Capital Ventures formed under the laws of
the Russian Federation (“BCP”).

RECITALS

A. CBL and BCP entered into that certain Participation Agreement dated
December 30, 2009 (the “Participation Agreement”) regarding the formation,
capitalization and governance of lncuron, LLC, a limited liability company
organized under the laws of the Russian Federation (the “Company”).

B. CBL and BCP entered into that certain First Amendment to Participation
Agreement dated April 13, 2010 regarding the terms of contributions to be made
to the Company.

C. CBL has entered into a Loan and Security Agreement (the “Loan”), dated
September 30, 2013, with Hercules Technology II, L.P., a Delaware limited
partnership (“Hercules”) pursuant to which CBL agreed to pledge certain
collateral, including CBL’s participation interests in the Company, as security.

D. The parties desire to amend the Participation Agreement to allow for the
pledge of participation interests as security.

NOW THEREFORE, in consideration of the foregoing and the mutual promises and
covenants set forth herein, CBL and BCP hereby amend the Participation Agreement
as follows:

1. Definitions. All capitalized terms not defined herein shall have the meanings
set forth in the Participation Agreement.

2. Definition of “Transfer” or “Transferring”. The definition of “Transfer” or
“Transferring” in Section 1. DEFINITIONS, is hereby amended and restated as
follows:

“Transfer” or “Transferring” means, subject to the following sentence, any sale,
assignment, disposition, transfer (including, without limitation, a transfer by
will or intestate distribution) or gift. “Transfer” or “Transferring” shall not
include any Participant’s grant of a security interest in and/or pledge of their
Participation Interests to a third party in accordance with the applicable laws.

 

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3. Effect of Amendment. Except for the amendments set forth herein, all other
provisions of the Participation Agreement shall be unaffected and shall remain
in full force and effect.

4. Counterparts. This Second Amendment may be executed in two or more
counterparts, each of which shall be deemed an original, but all of which
together shall constitute one and the same instrument. Delivery of an executed
counterpart of this Amendment electronically or by facsimile shall be effective
as delivery of an original executed counterpart of this Amendment, provided that
it shall be followed-up by an original of such counterpart signature within five
(5) business days thereafter.

5. Language. This Second Amendment has been made in Russian and English
language. In the event of a conflict or inconsistency between the English and
Russian versions of the agreement, the English version shall prevail.

[Signatures Follow]

 

LOGO [g756774img1.jpg]

 

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IN WITNESS WHEREOF, the Company and the Participants have executed this Second
Amendment as of the date first written above.

 

   

COMPANY:

 

INCURON, LLC

   LOGO [g756774xbrl_ex106st003a.jpg]     By:   

/s/ Andrey Leonov

       Name:    Andrey Leonov, Ph.D.        Title:    Chief Executive Officer   
   

PARTICIPANTS:

 

CLEVELAND BIOLABS, INC.

   LOGO [g756774xbrl_ex106st003b.jpg]     By:   

/s/ Yakov Kogan

       Name:    Yakov Kogan, Ph.D., MBA        Title:    Chief Executive Officer
       BIOPROCESS CAPITAL PARTNERS    LOGO [g756774xbrl_ex106st003c.jpg]     By
  

/s/ Vladimir Tezov

       Name:    Vladimir Tezov        Title:    Chief Executive Officer   

 

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