Exhibit 10.81
 
ASSIGNMENT AND ASSUMPTION AGREEMENT
 
    This Assignment and Assumption Agreement (the
“Assignment and Assumption Agreement”) is entered into as of April 12, 2013, by
and between Autilion AG, a company organized under the laws of Switzerland
(“Assignor”), and its affiliate, Bergamo Acquisition Corp PTE, LTD, a company
registered under the laws of the Republic of Singapore (“Assignee”). All terms
used, but not defined, herein shall have the meanings ascribed to them in the
Underlying Agreements (defined below).
 
    WHEREAS, Assignor and VistaGen Therapeutics, Inc., a corporation organized
under the laws of the State of Nevada (“VistaGen”), are parties to a Securities
Purchase Agreement and Voting Agreement, each dated April 8, 2013, complete
copies of which (including all exhibits, amendments and modifications thereto)
are incorporated herein by this reference (the “Underlying Agreements”);
 
    WHEREAS, Assignor has agreed to assign to Assignee all of its rights and
obligations under the Underlying Agreements (collectively, the “Assigned Rights
and Obligations”), and Assignee has agreed to assume the Assigned Rights and
Obligations.
 
    NOW, THEREFORE, for good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, the parties hereto agree as
follows:
 
1.  
Assignment and Assumption. Assignor hereby assigns to Assignee all of Assignor’s
rights and obligations under the Underlying Agreements with respect to the
Assigned Rights and Obligations, and Assignee hereby accepts the foregoing
assignment and assumes all of the rights and obligations of Assignor under the
Underlying Agreements with respect to the Assigned Rights and Obligations.

2.  
Effective Date. The date on which the Assignment and Assumption Agreement is
effective is April 11, 2013.

 
3.  
Successors. All future transfers and assignments of the Assigned Rights and
Obligations transferred and assigned hereby are subject to the transfer and
assignment provisions of the Underlying Agreements. This Assignment and
Assumption Agreement shall inure to the benefit of, and be binding upon, the
permitted successors and assigns of the parties hereto.

 
4. 
Counterparts. This Assignment and Assumption Agreement may be executed in
counterparts, each of which shall be an original, but all of which together
constitute one and the same instrument.

 
    IN WITNESS WHEREOF, Assignor and Assignee, by their duly authorized
officials, hereby execute and deliver this Assignment and Assumption Agreement,
effective as of the date set forth in Section 2 above.
 
 

ASSIGNOR: AUTILION AG   ASSIGNEE: BERGAMO ACQUISITION CORP PTE, LTD       By:
/s/ Hillard Herzog   By: /s/ Hillard Herzog Name: Hillard Herzog   Name: Hillard
Herzog Title: President   Title: President