AMENDMENT TO
REGISTRATION RIGHTS AGREEMENT

 
Amendment, dated as of April 28, 2008 (this “Amendment”), by and among
Neurologix, Inc., a Delaware corporation (the “Company”), General Electric
Pension Trust (“GE”), Chrysler LLC Master Retirement Trust (“Chrysler”), certain
funds managed by ProMed Asset Management LLC (collectively, “ProMed”) and
Corriente Master Fund, L.P. (“Corriente” and together with GE, Chrysler and
ProMed, collectively, the “Investors”).
 
WHEREAS, the Company and the Investors are parties to that certain Registration
Rights Agreement, dated as of November 19, 2007 (the “Registration Agreement”),
which provides for certain registration rights, relating to the Registrable
Securities held by the Investors, as more fully specified in the Registration
Agreement;
 
WHEREAS, the Company has authorized the issuance and sale of 142,857 shares of
the Series D Preferred Stock and 1,077,586 warrants to purchase Common Stock
(such warrants, together with such shares of Series D Preferred Stock, being
herewith called the “Additional Securities”) pursuant to the terms and
conditions of that certain Stock and Warrant Subscription Agreement (the “New
Series D Agreement”), dated as of even date herewith, by and between the
Company, Corriente and, solely with respect to Article V, GE; and
 
WHEREAS, the consummation of the purchase and sale of the Additional Securities
is contingent upon the execution and delivery by the requisite percentage in
interest of the Investors of this Amendment to provide for certain additional
registration rights as set forth herein.
 
NOW, THEREFORE, the Company and the parties signatory hereto agree as follows:
 
1. Unless otherwise specifically provided herein, all terms used and capitalized
in this Amendment, but which are not defined herein, shall be deemed to have the
respective meanings set forth in the Registration Agreement.
 
2. Section 2(a) of the Registration Agreement is hereby amended by adding a new
paragraph (vii) as follows:
 

“(vii) (t)                      At any time during the Special Registration
Period (as defined below), an Investor or Investors holding at least five
percent (5%) of the outstanding shares of Series D Preferred Stock may request,
in writing, the Company to register, and the Company shall use its reasonable
best efforts to register, under the Securities Act all or any portion of the
Registrable Securities held by such requesting Investor or Investors for sale in
the manner specified in such notice (the “Special Demand Notice”), provided that
the reasonably anticipated aggregate price to the public of such sale shall
exceed $1,000,000.  No demand may be made under this paragraph (vii) during a
S-3 Eligibility Period.  Upon proper request, the Company shall prepare and file
with the SEC a Demand Registration Statement (utilizing Rule 415 under the
Securities Act if so requested) to register the Registrable Securities referred
to in the Special Demand Notice.  The Company shall be required to effect only
one (1) registration statement pursuant to a request under this paragraph (vii);
provided, however that, if the number of Registrable Securities requested by a
requesting Investor or Investors to be included in the Demand Registration
Statement is reduced by twenty-five percent (25%) or more pursuant to Section
2(a)(v) hereof, the Company shall be required to effect one additional Demand
Registration Statement if so requested in accordance with this clause (t).  The
demand rights under this paragraph (vii) shall be in addition to the demand
rights set forth in paragraphs (i) and (ii) of this Section 2(a).
 

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(u)           For the purposes hereof, the “Special Registration Period” shall
mean the period starting on the earlier of (i) the date on which the Company
shall have completed its submission to the Food and Drug Administration of final
data relating to both its Phase 1 clinical trial for epilepsy and its Phase 2
clinical trial for Parkinson’s disease or (ii)  April 28, 2010, and ending on a
date which shall be nine (9) months following the date first to occur specified
in clause (i) or (ii) above.
 
(v)           Notwithstanding the foregoing, the Company may delay or suspend
the preparation and/or filing of a Demand Registration Statement pursuant to
this paragraph (vii) if, the Company had filed a registration statement for its
own account prior to the Company’s receipt of the Special Demand Notice, or the
Company receives board approval and executes a letter of intent with a
registered broker/dealer to serve as the lead underwriter in an underwritten
offering of the Company’s equity securities for aggregate gross proceeds to the
Company of at least $20,000,000.  The Company shall provide notice to the
requesting Investor or Investors of any such suspension or delay (a “Company
Suspension”) within ten (10) days of its receipt of a Special Demand
Notice.  The Company shall not be permitted to declare more than one (1) Company
Suspension.  In the event of a Company Suspension, an Investor or Investors,
holding the requisite percentage of Series D Preferred Stock, may request
registration under this paragraph (vii) effective at any time after the earlier
of (i) the termination of the underwriter’s engagement or (ii) the end of the
sixth (6th) month following the occurrence of the Company Suspension; provided,
however, that, if a registration statement for the Company’s underwritten
offering is declared effective during such six (6) month period, an Investor or
Investors shall not be permitted to request registration under this paragraph
(vii) before the expiration of any lock-up period restricting the sale of
Registrable Securities that such Investor or Investors shall have agreed to with
the lead underwriter.

 
(w)           Any Investor (a “Rule 415 Investor”) who (i) requests to have its
Registrable Securities included on a Demand Registration Statement, under
Section 2(a)(vii), that utilizes Rule 415 (or any similar rule or regulation of
the SEC) under the Securities Act and (ii) is required by the SEC, acting
pursuant to said Rule 415, to decrease (the “Rule 415 Decrease”) the number of
shares sold in such Demand Registration Statement (the “Rule 415 Shares”) may
request, in writing, the Company to register, and the Company shall use its
reasonable best efforts to register, under the Securities Act all or any portion
of the Rule 415 Shares held by such Rule 415 Investor for sale provided that the
reasonably anticipated aggregate price to the public of such sale shall exceed
$1,000,000.  No request may be made under this paragraph (vii)(w) during a S-3
Eligibility Period.  As long as Rule 415 Shares remain outstanding, there shall
be no limit on the number of times a Rule 415 Investor may request, and the
Company shall be required to register, such Rule 415 Shares, subject, however to
the provisions of paragraph (x) below.
 

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(x)           The Company shall not be required to file a registration statement
pursuant to Section 2(a)(vii)(w) above prior to the earlier of the first
business day following (1) the second anniversary of any then effective Demand
Registration Statement or (2) the sixtieth (60th) day after all Registrable
Securities registered under any then effective Demand Registration Statement
have been sold or otherwise transferred by the holder thereof.  The Company
shall not be obligated to file, cause to be filed or effect any Demand
Registration Statement pursuant to Section 2(a)(vii)(w) above if it has been
advised by the SEC that such registration statement will not be declared
effective due to prohibitions set forth in the federal securities laws or the
SEC’s interpretations thereof.
 
(y)           If a Demand Registration Statement that is filed pursuant to
Section 2(a)(vii)(t) or Section 2(a)(vii)(w) is not declared effective within
150 days (the “150 Day Period”) following the Company’s receipt of appropriate
notice from the Investor or the Investors, the Company shall pay to each holder
of Registrable Securities which is participating in such Demand Registration
Statement, in cash as liquidated damages and not as a penalty, an amount equal
to 1% (the “Liquidated Damages”) of the sum of (1) the Total Purchase Price (as
defined in the Series D Subscription Agreement) paid by such holder plus (2) the
Total Purchase Price (as defined in the Series C Subscription Agreement) paid by
such holder plus (3) the Total Purchase Price (as defined in the New Series D
Agreement) paid by such holder, following the expiration of the 150 Day Period
and for each 30 day period (pro rated for a part thereof) after the expiration
of the 150 Day Period until such Demand Registration Statement is declared
effective; provided, however, in no event shall the aggregate of the Liquidated
Damages paid to all holders under this Section 2(a)(vii)(y) exceed $1,000,000.
 
(z)           The Liquidated Damages shall not accrue a result of (1) a Demand
Registration Statement that is not declared effective due to the occurrence of
an event that constitutes force majeure, (2) a Demand Registration Statement
that is not declared effective due to comments from the SEC in respect of, or
directly related to, one or more Requesting Holders or Investors that is selling
shares in the Demand Registration Statement, in which case the Company shall
consult with the applicable holder with respect to such comments and use its
reasonable efforts to promptly respond to the SEC with respect to such comments
in order to have such Demand Registration Statement declared effective, (3) a
decrease in the number of Registrable Securities as a result of a Rule 415
Decrease (or any similar rule or regulation of the SEC) or (4) the Company not
being permitted pursuant to Section 2(a)(vii) to file a Demand Registration
Statement required pursuant to Section 2(a)(vii)(t) above.”
 
 
3. Section 2(a) (iii) of the Registration Agreement is hereby amended by adding
a reference to paragraph (vii) in the first sentence thereof as follows:
 
“(iii) Following receipt of any notice under paragraphs (i), (ii) or (vii) of
this Section 2(a)...”.
 
4. Section 2(a) (iv) of the Registration Agreement is hereby amended by adding a
reference to paragraph (vii) in the second line of the first sentence thereof as
follows:
 

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“...and when the Company is required by the provisions of paragraphs (i), (ii)
or (vii) of this Section 2(a) to register...”.
 
5. Section 2(a) (iv) (x) of the Registration Agreement is hereby amended by
adding a reference to paragraph (vii) in the eighth line thereof as follows:
 
“...as provided for in (i), (ii) or (vii) of this Section 2(a), a Demand
Registration Statement or a Shelf...”.
 
6. Section 2(b) of the Registration Agreement is hereby amended by deleting the
word “other” prior to “security holders” and inserting a parenthetical clause to
paragraph (i) in the third line of the first sentence thereof as follows:
 
“...for the account of security holders (other than the Investors) or both...”.
 
7. This Amendment will become effective upon the execution hereof by the Company
and Investors holding at least fifty percent (50%) in interest of the
Investors.  Except as amended hereby, the Registration Agreement, and the terms
and provisions thereof, shall remain in full force and effect.
 
8. This Amendment may be executed in one or more counterparts, each of which
shall constitute an original.  This Amendment, to the extent signed and
delivered by means of a facsimile machine or other electronic transmission,
shall be treated in all manner and respects and for all purposes as an original
agreement or instrument and shall be considered to have the same binding legal
effect as if it were the original signed version thereof delivered in person.
 
[Signature page follows.]
 

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IN WITNESS WHEREOF, the parties hereto have caused this Amendment to be duly
executed as of the day and year first above written.
 

NEUROLOGIX, INC.

By: /s/ John E. Mordock______________
Name: John E. Mordock
Title: President and Chief Executive Officer

By: /s/ Marc L. Panoff________________
Name: Marc L. Panoff
Title: Chief Financial Officer, Treasurer and Secretary

CORRIENTE MASTER FUND, L.P.
By Corriente Capital Management, L.P
Its managing general partner
By Corriente Advisors, LLC
Its General Partner

By: /s/ James Haddaway______________
Name: James Haddaway
Title: CFO
 

GENERAL ELECTRIC PENSION TRUST
By: GE Asset Management Incorporated,
        its Investment Manager

 
By: /s/ Daniel L. Furman______________
Name: Daniel L. Furman
Title: Vice President

 
CHRYSLER LLC MASTER RETIREMENT TRUST
By: State Street Bank and Trust Company
       as Trustee of the Chrysler LLC Master Retirement Trust

 
By: /s/ Steve Sovany_________________
Name: Steve Sovany
Title: Vice President

 
 
PROMED PARTNERS LP
 
By: /s/ Barry Kurokawa_______________
Name: Barry Kurokawa
Title: Managing Director