Exhibit 10.5

NEUROGESX, INC.

CONSULTING AGREEMENT

This Consulting Agreement (this “Agreement”) is entered into as of September 27,
2011 by and between NeurogesX, Inc., a Delaware corporation (the “Company”), and
Jeffrey Tobias, M.D., as of October 16, 2011, a former employee and executive of
the Company (“Consultant”). The Company desires to retain Consultant as an
independent contractor to perform certain limited consulting services for the
Company, and Consultant is willing to perform such limited services, on the
terms described below. In consideration of the mutual promises contained herein,
the parties agree as follows:

1. Services and Compensation. Beginning on October 16, 2011, Consultant agrees
to perform for the Company the services described in Exhibit A (the “Services”),
and the Company agrees to pay Consultant the compensation described in Exhibit A
for Consultant’s performance of the Services. For the avoidance of doubt, the
Company and Consultant hereby agree that the transition of Consultant from an
employee and executive to a consultant of the Company shall not constitute a
break of service provider status, and until such date the Consultant shall be
considered an employee of the Company.

2. Confidentiality.

A. Definition. “Confidential Information” means any non-public information that
relates to the actual or anticipated business or research and development of the
Company, technical data, trade secrets or know-how, including, but not limited
to, research, development, commercialization, strategic plans or other
information regarding the Company’s clinical trials, potential products,
products or markets therefore, software, developments, inventions, processes,
formulas, technology, designs, drawings, product formulations, clinical data,
strategy, marketing, finances or other business information. Confidential
Information does not include information that (i) is known to Consultant at the
time of disclosure to Consultant by the Company (other than through his prior
employment at the Company) as evidenced by written records of Consultant,
(ii) has become publicly known and made generally available through no wrongful
act of Consultant, (iii) has been independently developed by Consultant without
access to the Confidential Information, or (iv) has been rightfully received by
Consultant from a third party.

B. Limitations; Nonuse and Nondisclosure. Consultant does not wish to receive or
be granted access to, and the Company agrees to use its best efforts not to
disclose or provide Consultant access to, any Confidential Information not
strictly necessary for the provision of the Services. Consultant will not,
during or subsequent to the term of this Agreement, (i) use the Confidential
Information for any purpose whatsoever other than the performance of the
Services on behalf of the Company or (ii) disclose the Confidential Information
to any third party. Consultant agrees that all Confidential Information will
remain the sole property of the

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Company. Consultant also agrees to take all reasonable precautions to prevent
any unauthorized disclosure of such Confidential Information. The Company
consents to the disclosure of this Agreement to any future employer of
Consultant.

C. Former Client Confidential Information. Consultant agrees that Consultant
will not, during the term of this Agreement, improperly use or disclose any
proprietary information or trade secrets of any former or current employer of
Consultant or other person or entity with which Consultant has an agreement or
duty to keep in confidence information acquired by Consultant, if any.
Consultant also agrees that Consultant will not bring onto the Company’s
premises any unpublished document or proprietary information belonging to any
such employer, person or entity unless consented to in writing by such employer,
person or entity.

D. Third Party Confidential Information. (i) Consultant recognizes that the
Company has received and in the future will receive from third parties their
confidential or proprietary information subject to a duty on the Company’s part
to maintain the confidentiality of such information and to use it only for
certain limited purposes. Consultant agrees that, during the term of this
Agreement and thereafter, Consultant owes the Company and such third parties a
duty to hold all such confidential or proprietary information in the strictest
confidence and not to disclose it to any person, firm or corporation or to use
it except as necessary in carrying out the Services for the Company consistent
with the Company’s agreement with such third party.

(ii) The Company recognizes that during the term of this Agreement, Consultant
will receive confidential or proprietary information from third parties,
including Consultant’s future employer, which information is subject to a duty
on Consultant’s part to maintain as confidential and to use only for certain
limited purposes. Recognizing that Consultant owes such third parties such
duties, the Company agrees to use its best efforts to avoid placing Consultant
in a position where such third-party information must or must inevitably be used
in order for Consultant to perform the Services. It shall not be a breach of
this Agreement by Consultant for Consultant to refrain from performing any part
of the Services if in his reasonable opinion the performance of such Services
would require him to breach any duty owed to a third party.

E. Return of Materials. Upon the termination of this Agreement, or upon the
Company’s earlier request, Consultant will either deliver to the Company, or
certify to the Company that he has destroyed, all of the Company’s property then
in his possession or control, including but not limited to all electronically
stored information and passwords to access such property, and Confidential
Information that Consultant may then have in Consultant’s possession or control.

3. Ownership.

A. Assignment. Consultant agrees that all copyrightable material (including
computer source and object code), notes, records, drawings, designs, inventions,
improvements, developments, discoveries and trade secrets conceived, discovered,
developed or reduced to practice by Consultant, solely or in collaboration with
the Company’s employees, directors, independent contractors or agents, during
the term of this Agreement that relate in any manner to

 

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the Services or that Consultant invents, discovers, or develops in the course of
performing the Services under this Agreement other than for generally-applicable
expertise, ideas and know-how learned while performing the Services
(collectively, “Inventions”) are the sole property of the Company. Consultant
also agrees to assign (or cause to be assigned) and hereby assigns fully to the
Company all Inventions and any copyrights, patents, mask work rights or other
intellectual property rights relating to all Inventions. For the avoidance of
doubt, the term Inventions does not include any of the foregoing items (or
intellectual property rights therein or thereto) that Consultant may conceive,
discover, develop or reduce to practice as an employee of any other person
during the term of this Agreement.

B. Further Assurances. Consultant agrees to assist the Company, or its designee,
at the Company’s expense (and at Consultant’s then-standard consulting rate), in
every proper way to secure the Company’s rights in Inventions and any
copyrights, patents, mask work rights or other intellectual property rights
relating to all Inventions in any and all countries, including the disclosure to
the Company of all pertinent information and data with respect to all
Inventions, the execution of all applications, specifications, oaths,
assignments and other instruments that the Company may deem necessary in order
to apply for and obtain such rights and in order to assign and convey to the
Company and its successors, assigns and nominees the sole and exclusive right,
title and interest in and to all Inventions and any copyrights, patents, mask
work rights or other intellectual property rights relating to all Inventions.
Consultant also agrees that Consultant’s obligation to execute or cause to be
executed any such instrument or papers shall continue after the termination of
this Agreement.

C. Pre-Existing Materials. Subject to Section 3.A, Consultant agrees that if, in
the course of performing the Services, Consultant incorporates into any
Invention developed under this Agreement any pre-existing invention,
improvement, development, concept, discovery or other proprietary information
owned by Consultant or in which Consultant has an interest, (i) Consultant will
inform the Company, in writing, before incorporating such invention,
improvement, development, concept, discovery or other proprietary information
into any Invention, and (ii) the Company is hereby granted a nonexclusive,
royalty-free, perpetual, irrevocable, worldwide license to make, have made,
modify, use and sell such item as part of or in connection with such Invention.
Consultant will not incorporate any invention, improvement, development,
concept, discovery or other proprietary information owned by any third party
into any Invention without the Company’s prior written permission.

D. Attorney-in-Fact. Consultant agrees that, if the Company is unable because of
Consultant’s unavailability, dissolution or mental or physical incapacity, or
for any other reason, to secure Consultant’s signature for the purpose of
applying for or pursuing any application for any United States or foreign
patents or mask work or copyright registrations covering the Inventions assigned
to the Company in Section 3.A, then Consultant hereby irrevocably designates and
appoints the Company and its duly authorized officers and agents as Consultant’s
agent and attorney-in-fact, to act for and on Consultant’s behalf to execute and
file any such applications and to do all other lawfully permitted acts to
further the prosecution and issuance of patents and copyright and mask work
registrations with the same legal force and effect as if executed by Consultant.

 

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4. Conflicting Obligations. The Company acknowledges that Consultant has
accepted full time employment with another company, and that Consultant will be
serving in an executive research and development capacity with that company.
Requests for consulting services hereunder will be structured so as to not
interfere with such employment, and such employment (and any agreements required
to be entered by Consultant with such employer) will not be deemed to be an
agreement in conflict with this Agreement or any obligations that may be owed by
Consultant to the Company. In addition, the Company acknowledges that Consultant
will assign his inventions, broadly defined (but not any Invention (as defined
in Section 3.A. above)), to such employer, and that Consultant has and will have
confidentiality and fiduciary obligations to such employer. Subject to the
foregoing, Consultant certifies that Consultant has no outstanding agreement or
obligation that is in conflict with any of the provisions of this Agreement or
that would preclude Consultant from complying with the provisions of this
Agreement. Consultant will not enter into any such conflicting agreement during
the term of this Agreement (other than for such agreements that are required in
conjunction with Consultant’s service as an employee and executive officer for
such other company). Consultant acknowledges that Consultant and his new
employer have discussed and consented to the provision of Services to the extent
necessary to ensure that this Agreement and the provision of the Services
contemplated hereby are not in conflict with the Consultant’s provision of
services to the other employer and the other employer’s agreements and policies
that are binding on Consultant or may become binding on Consultant upon starting
services with the new employer. Consultant’s violation of this Section 4 will be
considered a material breach under Section 6.B.

5. Reports. Consultant also agrees that Consultant will, from time to time
during the term of this Agreement or any extension thereof, keep the Company
advised as to Consultant’s progress in performing the Services under this
Agreement. Consultant further agrees that Consultant will, as requested by the
Company, prepare written reports with respect to such progress. The Company and
Consultant agree that the time required to prepare such written reports will be
considered time devoted to the performance of the Services. Services described
in each such report will be deemed to have been satisfactorily performed by
Consultant unless the Company notifies Consultant in writing within ten
(10) business days following receipt of such report.

6. Term and Termination.

A. Term. The term of this Agreement will begin on the date of this Agreement and
will continue until the earlier of (i) nine (9) months from October 16, 2011 or
(ii) termination as provided in Section 6.B.

B. Termination. Either party may terminate this Agreement upon giving the other
party thirty (30) days’ prior written notice of such termination pursuant to
Section 9.E of this Agreement. Either party may terminate this Agreement
immediately and without prior notice if the other party refuses to or is unable
to perform its obligations hereunder or is in breach of any material provision
of this Agreement.

 

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C. Survival. Upon such termination, all rights and duties of the Company and
Consultant toward each other shall cease except:

(1) The Company will pay, within 30 days after the effective date of
termination, all amounts owing to Consultant for Services completed and accepted
by the Company prior to the termination date and related expenses, if any,
submitted in accordance with the Company’s policies and in accordance with the
provisions of Section 1 of this Agreement; and

(2) Section 2 (Confidentiality), Section 3 (Ownership), Section 4 (Conflicting
Obligations), Section 7 (Independent Contractor; Benefits; Limitation on
Liability; Indemnification) and Section 8 (Dispute Resolution; Equitable Relief)
will survive termination of this Agreement.

7. Independent Contractor; Benefits; Limitation on Liability; Indemnification.

A. Independent Contractor. It is the express intention of the Company and
Consultant that Consultant perform the Services as an independent contractor to
the Company. Nothing in this Agreement shall in any way be construed to
constitute Consultant as an agent, employee, fiduciary, trustee or
representative of the Company. Without limiting the generality of the foregoing,
and except as expressly set forth in Section 3 of this Agreement, neither party
is authorized to bind the other to any liability or obligation or to represent
that such party has any such authority, or to make any representations to any
other person on the other party’s behalf of in the other party’s name.
Consultant agrees to furnish (or reimburse the Company for) all tools and
materials necessary to accomplish this Agreement and shall incur all expenses
associated with performance, except as expressly provided in Exhibit A.
Consultant acknowledges and agrees that Consultant is obligated to report as
income all compensation received by Consultant pursuant to this Agreement.
Consultant agrees to and acknowledges the obligation to pay all self-employment
and other taxes on such income.

B. Benefits. The Company and Consultant agree that Consultant will receive no
Company-sponsored benefits from the Company in connection with Consultant’s
status under this Agreement (it being acknowledged by the Company that nothing
in this Agreement is intended to or shall affect, modify, supersede or terminate
any Company-sponsored benefits to which Consultant is or may be entitled as a
former employee and senior executive of the Company). If Consultant is
reclassified by a state or federal agency or court as the Company’s employee,
Consultant will become a reclassified employee and will receive no benefits from
the Company, except those mandated by state or federal law, even if by the terms
of the Company’s benefit plans or programs in effect at the time of such
reclassification, Consultant would otherwise be eligible for such benefits.

C. Limitation on Liability. EXCEPT AS CONTAINED IN THIS AGREEMENT, CONSULTANT
MAKES NO, AND DISCLAIMS ANY, REPRESENTATIONS AND WARRANTIES TO THE COMPANY,
EXPRESS OR IMPLIED, REGARDING THE SERVICES TO BE PROVIDED HEREUNDER, INCLUDING,
BUT NOT LIMITED TO, IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
PARTICULAR PURPOSE, SUITABILITY, AND NON-INFRINGEMENT. TO THE EXTENT THE
SERVICES CONSTITUTE BUSINESS, TECHNICAL OR OTHER ADVICE, THE DECISION TO
IMPLEMENT SUCH ADVICE, OR TO INCORPORATE SUCH ADVICE INTO A TRIAL, REPORT,
PRODUCT, THERAPY, SERVICE OR BUSINESS DECISION FOR THE COMPANY

 

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OR A THIRD PARTY IS TO BE MADE BY THE COMPANY AND, AS BETWEEN THE PARTIES, THE
COMPANY SHALL BE RESPONSIBLE FOR THE CONSEQUENCES OF SUCH IMPLEMENTATION OR
INCORPORATION. THE PARTIES ACKNOWLEDGE THAT THIS LIMITATION OF LIABILITY IS FAIR
AND REASONABLE.

D. Indemnification. The Company hereby agrees to indemnify, defend and hold
Consultant harmless from and against any and all claims, liability, suits,
losses, costs and legal fees (“Claims”) arising out of the entry into this
Agreement, the performance of the Services hereunder, the further development
testing, studies, marketing, commercialization, use by any person of any drug or
drug candidate as to which Services are performed hereunder, or resulting from
any willful misconduct or negligent act or omission of the Company, except to
the extent that any such Claims are determined to have been caused by the
willful misconduct or negligent act or omission of Consultant. The Company
represents that Consultant is eligible to continue to be insured under its
applicable products and general liability insurance policies as if Consultant
were still an executive employee of the Company, and covenants to continue to
cover Consultant thereunder to the same such extent during the term of this
Agreement.

8. Dispute Resolution; Equitable Relief.

A. Dispute Resolution. In the unlikely event of a dispute (other than a dispute
that is subject to Section 8(B)) between the parties, the parties, together with
one or more advisors or neutral parties if they choose to bring them, will meet
informally to attempt to resolve the dispute in good faith. If after 21 days the
parties have been unable to resolve their dispute informally, neither party
shall then be precluded from pursuing court action or administrative relief.

B. Equitable Relief. Consultant agrees that it would be impossible or inadequate
to measure and calculate the Company’s damages from any breach of the covenants
set forth in Section 2 (Confidentiality) and Section 3 (Ownership) of his
Agreement. Accordingly, Consultant agrees that if Consultant breaches Section 2
(Confidentiality) and Section 3 (Ownership) of this Agreement, the Company will
have available, in addition to any other right or remedy available, the right to
obtain from any court of competent jurisdiction an injunction restraining such
breach or threatened breach and specific performance of any such provision.

9. Miscellaneous.

A. Governing Law. This Agreement shall be governed by the laws of California
without regard to California’s conflicts of law rules.

B. Assignability. Except as otherwise provided in this Agreement, Consultant may
not sell, assign or delegate any rights or obligations under this Agreement. The
terms of this Agreement and all rights of Consultant hereunder shall inure to
the benefit of, and be enforceable by, Consultant’s personal or legal
representatives, executives, administrators, successors, heirs, devisees and
legatees.

C. Entire Agreement. This Agreement constitutes the entire agreement between the
parties with respect to the subject matter of this Agreement and supersedes all
prior written and

 

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oral agreements between the parties regarding the subject matter of this
Agreement. For purposes of clarity, unless specifically set forth herein,
nothing in this Agreement is intended to or shall affect, modify, supersede or
terminate any agreement, right or obligation of either party under any agreement
that by its terms survives the termination of Consultant’s employment
relationship with the Company, including, but not limited to, any rights to any
rights Consultant may have to indemnification under any agreement, director and
officer liability insurance policy, or the Company’s Bylaws and/or Certificate
of Incorporation.

D. Headings. Headings are used in this Agreement for reference only and shall
not be considered when interpreting this Agreement.

E. Notices. Any notice or other communication required or permitted by this
Agreement to be given to a party shall be in writing and shall be deemed given
if delivered personally or by commercial messenger or courier service, or mailed
by U.S. registered or certified mail (return receipt requested), or sent via
facsimile (with receipt of confirmation of complete transmission), to the party
at the party’s address or facsimile number written below or at such other
address or facsimile number as the party may have previously specified by like
notice. If by mail, delivery shall be deemed effective 3 business days after
mailing in accordance with this Section 9.E.

(1) If to the Company, to:

  NeurogesX, Inc.

  2215 Bridgepointe Parkway, Suite 200

  San Mateo, CA 94404

  Attention: Chief Executive Officer

  Telephone: 650-358-3300

  Facsimile: 650-412-1999

(2) If to Consultant, to the address for notice on the signature page to this
Agreement or, if no such address is provided, to the last address of Consultant
provided by Consultant to the Company.

F. Attorneys’ Fees. In any court action at law or equity that is brought by one
of the parties to this Agreement to enforce or interpret the provisions of this
Agreement, the prevailing party will be entitled to reasonable attorneys’ fees,
in addition to any other relief to which that party may be entitled.

G. Severability. If any provision of this Agreement is found to be illegal or
unenforceable, the other provisions shall remain effective and enforceable to
the greatest extent permitted by law and the parties shall negotiate a legal and
enforceable provision that most closely accomplishes their original intent to
replace such illegal or unenforceable provision.

(The remainder of this page is intentionally left blank.)

 

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IN WITNESS WHEREOF, the parties hereto have executed this Consulting Agreement
as of the date first written above.

 

CONSULTANT     NEUROGESX, INC.

/s/ Jeffrey K. Tobias

    By:  

/s/ Stephen Ghiglieri

Name:   Jeffrey K. Tobias     Name:   Stephen Ghiglieri       Title:   EVP, COO
& CFO Address for Notice:       2275 Broadway St., Apt. 518       San Francisco,
CA 94115      

 

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EXHIBIT A

Services and Compensation

1. Contact. Consultant’s principal Company contact:

Name: Anthony DiTonno

Title:   Chief Executive Officer

2. Services. The Services shall include the following:

Consultant shall provide up to sixteen (16) hours per month of Services as
requested by the Company and agreed upon (including as to scope and timing) by
the Consultant for the following:

 

  a. Provide advice to appropriate Company personnel (i) on commercialization
and label expansion efforts for Qutenza, including with respect to the
submission of the supplemental New Drug Application for Qutenza to expand the
Qutenza label to include management of pain due to HIV-associated peripheral
neuropathy and (ii) in preparation for a potential advisory committee meeting
with the FDA.

 

  b. Provide advice to appropriate Company personnel on development of NGX-1998,
including supporting such personnel in the analysis of results and data from the
currently ongoing Phase 2 clinical trial for NGX-1998.

3. Compensation.

A. For providing the Services, Consultant will be paid $450 per hour of Service
($7,200 per month based on 16 hours of Service) during the term of this
Agreement.

B. Restricted Stock Units issued to the Consultant under the Company 2007’s
Stock Plan (as amended) (the “Plan”) while Consultant was still an employee of
the Company shall continue to vest during the time that Consultant’s Continuous
Service (as defined in the Consultant’s Restricted Stock Unit Agreement) with
the Company continues, provided that the transition of Consultant from an
employee of the Company to a consultant of the Company shall be deemed not to be
a break of Continuous Service.

C. Options to purchase shares of the Company’s Common Stock (the “Options”) held
by Consultant as of the date of this Agreement shall continue to vest during the
term of this Agreement as if the Consultant’s status as a service provider to
the Company necessary to continue the vesting of the Time-Based Options was not
interrupted by the transition of the Consultant from an employee to a consultant
of the Company.

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D. Upon termination of this Agreement, all of Consultant’s then outstanding
Options shall be deemed amended to extend the post-termination option exercise
period during which the Consultant can exercise such options to twelve
(12) months.

E. The Company will reimburse Consultant for reasonable and actual expenses
incurred by the Consultant in carrying out the subject of the consulting
arrangement, including reasonable and actual travel, modest meals and lodging
costs incurred by Consultant in performing the Services pursuant to this
Agreement, if Consultant submits receipts for such expenses to the Company in
accordance with Company policy.

F. Every month, Consultant shall submit to the Company a written invoice for
services rendered and expenses, and such statement shall be subject to the
approval of the contact person listed above or other designated agent of the
Company.

 

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