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                                                                    EXHIBIT 4.3

                          SOMAXON PHARMACEUTICALS, INC.
                        2005 EMPLOYEE STOCK PURCHASE PLAN

                                   ARTICLE I

                                     PURPOSE

      The purposes of this Somaxon Pharmaceuticals, Inc. 2005 Employee Stock
Purchase Plan (the "PLAN") are to assist Eligible Employees of Somaxon
Pharmaceuticals, Inc., a Delaware corporation (the "COMPANY") and its
Subsidiaries in acquiring a stock ownership interest in the Company pursuant to
a plan which is intended to qualify as an "employee stock purchase plan" within
the meaning of Section 423(b) of the Code, and to help Eligible Employees
provide for their future security and to encourage them to remain in the
employment of the Company and its Subsidiaries.

      All share numbers set forth in this Plan give effect to the reverse stock
split implemented by the Company in connection with its initial public offering.

                                   ARTICLE II

                          DEFINITIONS AND CONSTRUCTION

      Wherever the following terms are used in the Plan they shall have the
meanings specified below, unless the context clearly indicates otherwise. The
singular pronoun shall include the plural where the context so indicates.

      2.1 "ADMINISTRATOR" means the entity that conducts the general
administration of the Plan as provided herein. The term "ADMINISTRATOR" shall
refer to the Committee unless the Board has assumed the authority for
administration of the Plan generally as provided in Article 3.

      2.2 "BOARD" shall mean the Board of Directors of the Company.

      2.3 "CHANGE IN CONTROL" means and includes each of the following:

            (a) the acquisition, directly or indirectly, by any "person" or
"group" (as those terms are defined in Sections 3(a)(9), 13(d) and 14(d) of the
Exchange Act and the rules thereunder) of "beneficial ownership" (as determined
pursuant to Rule 13d-3 under the Exchange Act) of securities entitled to vote
generally in the election of directors ("VOTING SECURITIES") of the Company that
represent 50% or more of the combined voting power of the Company's then
outstanding voting securities, other than:

                  (i) an acquisition by a trustee or other fiduciary holding
      securities under any employee benefit plan (or related trust) sponsored or
      maintained by the Company or any person controlled by the Company or by
      any employee benefit plan (or related trust) sponsored or maintained by
      the Company or any person controlled by the Company, or

                  (ii) an acquisition of voting securities by the Company or a
      corporation owned, directly or indirectly by the stockholders of the
      Company in substantially the same proportions as their ownership of the
      stock of the Company,

                  (iii) an acquisition of voting securities pursuant to a
      transaction described in subsection (b) below that would not be a Change
      in Control under subsection (b), or

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                  (iv) an acquisition of voting securities pursuant to the
      Company's initial public offering of the Stock;

         Notwithstanding the foregoing, the following event shall not constitute
an "acquisition" by any person or group for purposes of this Section 2.3: an
acquisition of the Company's securities by the Company which causes the
Company's voting securities beneficially owned by a person or group to represent
50% or more of the combined voting power of the Company's then outstanding
voting securities; provided, however, that if a person or group shall become the
beneficial owner of 50% or more of the combined voting power of the Company's
then outstanding voting securities by reason of share acquisitions by the
Company as described above and shall, after such share acquisitions by the
Company, become the beneficial owner of any additional voting securities of the
Company, then such acquisition shall constitute a Change in Control; or

            (b) the consummation by the Company (whether directly involving the
Company or indirectly involving the Company through one or more intermediaries)
of (x) a merger, consolidation, reorganization, or business combination or (y) a
sale or other disposition of all or substantially all of the Company's assets or
(z) the acquisition of assets or stock of another entity, in each case other
than a transaction:

                  (i) which results in the Company's voting securities
      outstanding immediately before the transaction continuing to represent
      (either by remaining outstanding or by being converted into voting
      securities of the Company or the person that, as a result of the
      transaction, controls, directly or indirectly, the Company or owns,
      directly or indirectly, all or substantially all of the Company's assets
      or otherwise succeeds to the business of the Company (the Company or such
      person, the "SUCCESSOR ENTITY") directly or indirectly, at least a
      majority of the combined voting power of the Successor Entity's
      outstanding voting securities immediately after the transaction, and

                  (ii) after which no person or group beneficially owns voting
      securities representing 50% or more of the combined voting power of the
      Successor Entity; provided, however, that no person or group shall be
      treated for purposes of this paragraph (ii) as beneficially owning 50% or
      more of combined voting power of the Successor Entity solely as a result
      of the voting power held in the Company prior to the consummation of the
      transaction; or

            (c) the Company's stockholders approve a liquidation or dissolution
of the Company.

         For purposes of subsection (a) above, the calculation of voting power
shall be made as if the date of the acquisition were a record date for a vote of
the Company's stockholders, and for purposes of subsection (b) above, the
calculation of voting power shall be made as if the date of the consummation of
the transaction were a record date for a vote of the Company's stockholders.

         The Administrator shall have full and final authority, which shall be
exercised in its discretion, to determine conclusively whether a Change in
Control of the Company has occurred pursuant to the above definition, and the
date of the occurrence of such Change in Control and any incidental matters
relating thereto.

      2.4 "CODE" shall mean the Internal Revenue Code of 1986, as amended from
time to time, and the regulations issued thereunder.

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      2.5 "COMMITTEE" means the committee of the Board described in Article 3.

      2.6 "COMPANY" shall mean Somaxon Pharmaceuticals, Inc., a Delaware
corporation.

      2.7 "COMPENSATION" of an Eligible Employee shall mean the gross base
compensation received by such Eligible Employee as compensation for services to
the Company or any Designated Subsidiary, excluding overtime payments, sales
commissions, incentive compensation, bonuses, expense reimbursements, fringe
benefits and other special payments.

      2.8 "DESIGNATED SUBSIDIARY" shall mean any Subsidiary designated by the
Administrator in accordance with Section 3.3(ii).

      2.9 "ELIGIBLE EMPLOYEE" shall mean an Employee of the Company or a
Designated Subsidiary: (i) who does not, immediately after any rights under this
Plan are granted, own (directly or through attribution) stock possessing 5% or
more of the total combined voting power or value of all classes of Stock or
other stock of the Company, a Parent or a Subsidiary (as determined under
Section 423(b)(3) of the Code); (ii) whose customary employment is for more than
twenty hours per week; and (iii) whose customary employment is for more than
five months in any calendar year; provided, however, that the Administrator may
provide in an Offering Document that (x) Employees who are highly compensated
employees within the meaning of Section 423(b)(4)(D) of the Code, and/or (y)
Employees who have not met a service requirement designated by the Administrator
pursuant to Section 423(b)(4)(A) of the Code (which service requirement may not
exceed two years), shall not be eligible to participate in an Offering Period.
For purposes of clause (i) above, the rules of Section 424(d) of the Code with
regard to the attribution of stock ownership shall apply in determining the
stock ownership of an individual, and stock which an Employee may purchase under
outstanding options shall be treated as stock owned by the Employee. For
purposes of the Plan, the employment relationship shall be treated as continuing
intact while the individual is on sick leave or other leave of absence approved
by the Company or a Designated Subsidiary and meeting the requirements of
Treasury Regulation Section 1.421-7(h)(2).

      2.10 "EMPLOYEE" means any officer or other employee (as defined in
accordance with Section 3401(c) of the Code) of the Company or any Designated
Subsidiary.

      2.11 "ENROLLMENT DATE" shall mean the first day of each Offering Period.

      2.12 "EXCHANGE ACT" shall mean the Securities Exchange Act of 1934, as
amended from time to time.

      2.13 "FAIR MARKET VALUE" shall mean, as of any date, the value of Stock
determined as follows:

         (a) If the Stock is listed on any established stock exchange or a
national market system, including without limitation the Nasdaq National Market
or The Nasdaq SmallCap Market of The Nasdaq Stock Market, its Fair Market Value
shall be the closing sales price for such stock as quoted on such exchange or
system for the last Trading Day prior to the date of determination for which a
closing sales price was reported, as reported in The Wall Street Journal or such
other source as the Administrator deems reliable;

         (b) If the Stock is regularly quoted by a recognized securities dealer
but selling prices are not reported, its Fair Market Value shall be the mean of
the closing bid and asked prices for the Stock on the date prior to the date of
determination as reported in The Wall Street Journal or such other source as the
Administrator deems reliable; or

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         (c) In the absence of an established market for the Stock, the Fair
Market Value thereof shall be determined in good faith by the Administrator.

      2.14 "OFFERING DOCUMENT" shall have the meaning given to such term in
Section 5.1.

      2.15 "OFFERING PERIOD" shall mean each Offering Period designated by the
Administrator in the applicable Offering Document pursuant to Section 5.1.

      2.16 "PARENT" means any corporation, other than the Company, in an
unbroken chain of corporations ending with the Company if, at the time of the
determination, each of the corporations other than the Company owns stock
possessing 50% or more of the total combined voting power of all classes of
stock in one of the other corporations in such chain.

      2.17 "PARTICIPANT" means any Eligible Employee who has executed a
participation agreement and been granted rights to purchase Stock pursuant to
the Plan.

      2.18 "PLAN" shall mean this Somaxon Pharmaceuticals, Inc. 2005 Employee
Stock Purchase Plan, as it may be amended from time to time.

      2.19 "PURCHASE DATE" shall mean the last day of each Purchase Period.

      2.20 "PURCHASE PERIOD" shall mean each Purchase Period designated by the
Administrator in the applicable Offering Document pursuant to Section 5.1. A new
Purchase Period will begin on the day immediately following a Purchase Date.

      2.21 "PURCHASE PRICE" shall mean the purchase price designated by the
Administrator in the applicable Offering Document (which purchase price shall
not be less than 85% of the Fair Market Value of a share of Stock on the
Enrollment Date or on the Purchase Date, whichever is lower); provided, however,
that, in the event no purchase price is designated by the Administrator in the
applicable Offering Document, the purchase price for the Offering Periods
covered by such Offering Document shall be 85% of the Fair Market Value of a
share of Stock on the Enrollment Date or on the Purchase Date, whichever is
lower); provided, further, that the Purchase Price may be adjusted by the
Administrator pursuant to Article 9; provided, further, that the Purchase Price
shall not be less than the par value of a share of Stock.

      2.22 "SECURITIES ACT" shall mean the Securities Act of 1933, as amended
from time to time.

      2.23 "STOCK" means the common stock of the Company and such other
securities of the Company that may be substituted for Stock pursuant to Article
9.

      2.24 "SUBSIDIARY" shall mean any corporation, other than the Company, in
an unbroken chain of corporations beginning with the Company if, at the time of
the determination, each of the corporations other than the last corporation in
an unbroken chain owns stock possessing 50% or more of the total combined voting
power of all classes of stock in one of the other corporations in such chain.

      2.25 "TRADING DAY" shall mean a day on which national stock exchanges and
the Nasdaq System are open for trading.

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                                  ARTICLE III

                                 ADMINISTRATION

      3.1 Administrator. The Administrator of the Plan shall be the Compensation
Committee of the Board (or another committee or a subcommittee of the Board to
which the Board delegates administration of the Plan) (such committee, the
"COMMITTEE"), which Committee shall consist solely of two or more members of the
Board each of whom is a "non-employee director" within the meaning of Rule 16b-3
which has been adopted by the Securities and Exchange Commission under the
Exchange Act and which Committee is otherwise constituted to comply with
applicable law. Appointment of Committee members shall be effective upon
acceptance of appointment. The Board may abolish the Committee at any time and
revest in the Board the administration of the Plan. Committee members may resign
at any time by delivering written notice to the Board. Vacancies in the
Committee may only be filled by the Board.

      3.2 Action by the Administrator. A majority of the Administrator shall
constitute a quorum. The acts of a majority of the members present at any
meeting at which a quorum is present, and, subject to applicable law and the
Bylaws of the Company, acts approved in writing by a majority of the
Administrator in lieu of a meeting, shall be deemed the acts of the
Administrator. Each member of the Administrator is entitled to, in good faith,
rely or act upon any report or other information furnished to that member by any
officer or other employee of the Company or any Designated Subsidiary, the
Company's independent certified public accountants, or any executive
compensation consultant or other professional retained by the Company to assist
in the administration of the Plan.

      3.3 Authority of Administrator. The Administrator shall have the power,
subject to, and within the limitations of, the express provisions of the Plan:

            (i) To determine when and how rights to purchase stock of the
Company shall be granted and the provisions of each offering of such rights
(which need not be identical).

            (ii) To designate from time to time which Subsidiaries of the
Company shall be Designated Subsidiaries, which designation may be made without
the approval of the stockholders of the Company.

            (iii) To construe and interpret the Plan and rights granted under
it, and to establish, amend and revoke rules and regulations for its
administration. The Administrator, in the exercise of this power, may correct
any defect, omission or inconsistency in the Plan, in a manner and to the extent
it shall deem necessary or expedient to make the Plan fully effective.

            (iv) To amend the Plan as provided in Article 10.

            (v) Generally, to exercise such powers and to perform such acts as
the Administrator deems necessary or expedient to promote the best interests of
the Company and its Subsidiaries and to carry out the intent that the Plan be
treated as an "employee stock purchase plan" within the meaning of Section 423
of the Code.

      3.4 Decisions Binding. The Administrator's interpretation of the Plan, any
rights granted pursuant to the Plan, any participation agreement and all
decisions and determinations by the Administrator with respect to the Plan are
final, binding, and conclusive on all parties.

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                                   ARTICLE IV

                           SHARES SUBJECT TO THE PLAN

      4.1 Number of Shares. Subject to Article 9, the aggregate number of shares
of Stock which may be issued pursuant to rights granted under the Plan shall be
300,000 shares. In addition to the foregoing, subject to Article 9, commencing
on January 1, 2007, and on each January 1 thereafter during the term of the
Plan, the number of shares of Stock which shall be made available for sale under
the Plan shall be increased by that number of shares of Stock equal to the least
of (a) 1% of the Company's outstanding shares on such date, (b) 300,000 shares,
or (c) a lesser amount determined by the Board. Accordingly, the number of
shares of Stock which shall be available for sale under the Plan shall be
subject to increase under the preceding sentence only on January 1, 2007 and on
each subsequent January 1 through and including January 1, 2015. If any right
granted under the Plan shall for any reason terminate without having been
exercised, the Stock not purchased under such right shall again become available
for the Plan. Notwithstanding anything in this Section 4.1 to the contrary, the
number of shares of Stock that may be issued or transferred pursuant to rights
granted under the Plan shall not exceed an aggregate of 3,000,000 shares,
subject to Article 9.

      4.2 Stock Distributed. Any Stock distributed pursuant to the Plan may
consist, in whole or in part, of authorized and unissued Stock, treasury stock
or Stock purchased on the open market.

                                   ARTICLE V

              OFFERING PERIODS; OFFERING DOCUMENTS; PURCHASE DATES

      5.1 Offering Periods. The Administrator may from time to time grant or
provide for the grant of rights to purchase Stock of the Company under the Plan
to Eligible Employees during one or more periods (each, an "OFFERING PERIOD")
selected by the Administrator commencing on such dates (each, an "ENROLLMENT
DATE") selected by the Administrator. The terms and conditions applicable to
each Offering Period shall be set forth in an "OFFERING DOCUMENT" adopted by the
Administrator, which Offering Document shall be in such form and shall contain
such terms and conditions as the Administrator shall deem appropriate and shall
be incorporated by reference into and made part of the Plan and shall be
attached hereto as part of the Plan. The Administrator shall establish in each
Offering Document one or more dates during an Offering Period (the "PURCHASE
DATE(S)") on which rights granted under the Plan shall be exercised and
purchases of Stock carried out during such Offering Period in accordance with
such Offering Document and the Plan. The provisions of separate Offering Periods
under the Plan need not be identical.

      5.2 Offering Documents. Each Offering Document with respect to an Offering
Period shall specify (through incorporation of the provisions of this Plan by
reference or otherwise):

            (i) the length of the Offering Period, which period shall not exceed
twenty-seven months;

            (ii) the Enrollment Date for such Offering Period;

            (iii) the Purchase Date(s) during such Offering Period;

            (iv) the maximum number of shares that may be purchased by any
Eligible Employee during such Offering Period;

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            (v) in connection with each Offering Period that contains more than
one Purchase Date, the maximum aggregate number of shares which may be purchased
by any Eligible Employee on any given Purchase Date during the Offering Period;
and

            (vi) such other provisions as the Administrator determines are
appropriate, subject to the Plan.

                                   ARTICLE VI

                                  PARTICIPATION

      6.1 Eligibility. Any Eligible Employee who shall be employed by the
Company or a Designated Subsidiary on the day immediately preceding a given
Enrollment Date for an Offering Period shall be eligible to participate in the
Plan during such Offering Period, subject to the requirements of this Article 6
and the limitations imposed by Section 423(b) of the Code.

      6.2 Enrollment in Plan. Except as otherwise set forth in an Offering
Document, an Eligible Employee may become a Participant in the Plan for an
Offering Period by delivering a participation agreement to the Company prior to
the Enrollment Date for such Offering Period (or such other date specified in
the Offering Document), in such form as the Administrator provides. Each such
agreement shall designate a whole percentage of such Eligible Employee's
Compensation to be withheld by the Company or the Designated Subsidiary
employing such Eligible Employee on each payday during the Offering Period as
payroll deductions under the Plan. An Eligible Employee may designate any whole
percentage of Compensation which is not less than 1% and not more than the
maximum percentage specified by the Administrator in the applicable Offering
Document (which percentage shall be 20% in the absence of any such designation)
as payroll deductions. The payroll deductions made for each Participant shall be
credited to an account for such Participant under the Plan and shall be
deposited with the general funds of the Company. A Participant may change the
percentage of Compensation designated in his or her participation agreement,
subject to the limits of this Section 6.2, or may suspend his or her payroll
deductions, or may resume payroll deductions pursuant to a new participation
agreement, at any time during an Offering Period; provided, however, that the
Administrator may limit the number of changes a Participant may make to his or
her payroll deduction elections during each Offering Period and/or Purchase
Period in the applicable Offering Document. Any such change, suspension or
resumption of payroll deductions shall be effective with the first full payroll
period following five business days after the Company's receipt of the new
participation agreement (or such shorter or longer period as may be specified by
the Administrator in the applicable Offering Document). In the event a
Participant suspends his or her payroll deductions, such Participant's
cumulative payroll deductions prior to the suspension shall remain in his or her
account and shall not be paid to such Participant unless he or she withdraws
from participation in the Plan pursuant to Article 8. Except as otherwise set
forth in an Offering Document, a Participant may participate in the Plan only by
means of payroll deduction and may not make contributions by lump sum payment
for any Offering Period.

      6.3 Payroll Deductions. Except as otherwise provided in the applicable
Offering Document, payroll deductions for a Participant shall commence on the
first payroll following the Enrollment Date and shall end on the last payroll in
the Offering Period to which such authorization is applicable, unless sooner
terminated by the Participant as provided in Article 9.

      6.4 Effect of Enrollment. A Participant's completion of a participation
agreement will enroll such Participant in the Plan for each successive Purchase
Period and each subsequent Offering Period on the terms contained therein until
the Participant either submits a new participation agreement, withdraws from
participation under the Plan as provided in Article 8 or otherwise becomes
ineligible to participate in the Plan.

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      6.5 Limitation on Purchase of Stock. An Eligible Employee may be granted
rights under the Plan only if such rights, together with any other rights
granted to such Eligible Employee under "employee stock purchase plans" of the
Company, any Parent or any Subsidiary, as specified by Section 423(b)(8) of the
Code, do not permit such employee's rights to purchase stock of the Company or
any Parent or Subsidiary to accrue at a rate which exceeds $25,000 of fair
market value of such stock (determined as of the first day of the Offering
Period during which such rights are granted) for each calendar year in which
such rights are outstanding at any time. This limitation shall be applied in
accordance with Section 423(b)(8) of the Code.

      6.6 Decrease of Payroll Deductions. Notwithstanding the foregoing, to the
extent necessary to comply with Section 423(b)(8) of the Code and Section 6.5, a
Participant's payroll deductions may be suspended by the Administrator at any
time during an Offering Period.

                                  ARTICLE VII

                          GRANT AND EXERCISE OF RIGHTS

      7.1 Grant of Rights. On the Enrollment Date of each Offering Period, each
Eligible Employee participating in such Offering Period shall be granted a right
to purchase the maximum number of shares of Stock specified under Section
5.2(iv) and shall have the right to buy, on each Purchase Date during such
Offering Period (at the applicable Purchase Price), such number of shares of the
Company's Stock as is determined by dividing (a) such Participant's payroll
deductions accumulated prior to such Purchase Date and retained in the
Participant's account as of the Purchase Date, by (b) the applicable Purchase
Price. The right shall expire on the last day of the Offering Period.

      7.2 Exercise of Rights. On each Purchase Date, each Participant's
accumulated payroll deductions and any other additional payments specifically
provided for in the applicable Offering Document will be applied to the purchase
of whole shares of Stock of the Company, up to the maximum number of shares
permitted pursuant to the terms of the Plan and the applicable Offering
Document, at the Purchase Price. No fractional shares shall be issued upon the
exercise of rights granted under the Plan, unless the Offering Document
specifically provides otherwise. The amount, if any, of accumulated payroll
deductions remaining in each Participant's account after the purchase of shares
on each Purchase Date shall be distributed in full to the Participant after such
Purchase Date.

      7.3 Pro Rata Allocation of Shares. If the Administrator determines that,
on a given Purchase Date, the number of shares of Stock with respect to which
rights are to be exercised may exceed (i) the number of shares of Stock that
were available for issuance under the Plan on the Enrollment Date of the
applicable Offering Period, or (ii) the number of shares of Stock available for
issuance under the Plan on such Purchase Date, the Administrator may in its sole
discretion provide that the Company shall make a pro rata allocation of the
shares of Stock available for purchase on such Enrollment Date or Purchase Date,
as applicable, in as uniform a manner as shall be practicable and as it shall
determine in its sole discretion to be equitable among all Participants for whom
rights to purchase Stock are to be exercised pursuant to this Article 7 on such
Purchase Date, and shall either (x) continue all Offering Periods then in
effect, or (y) terminate any or all Offering Periods then in effect pursuant to
Article 10. The Company may make pro rata allocation of the shares available on
the Enrollment Date of any applicable Offering Period pursuant to the preceding
sentence, notwithstanding any authorization of additional shares for issuance
under the Plan by the Company's stockholders subsequent to such Enrollment Date.
The balance of the amount credited to the account of each Participant which has
not been applied to the purchase of shares of stock shall be paid to such
Participant in one lump sum in cash as soon as reasonably practicable after the
Purchase Date.

      7.4 Withholding. At the time a Participant's rights under the Plan are
exercised, in whole or in part, or at the time some or all of the Stock issued
under the Plan is disposed of, the Participant must

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make adequate provision for the Company's federal, state, or other tax
withholding obligations, if any, which arise upon the exercise of the right or
the disposition of the Stock. At any time, the Company may, but shall not be
obligated to, withhold from the Participant's compensation the amount necessary
for the Company to meet applicable withholding obligations, including any
withholding required to make available to the Company any tax deductions or
benefits attributable to sale or early disposition of Stock by the Participant.

      7.5 Conditions to Issuance of Stock. The Company shall not be required to
issue or deliver any certificate or certificates for shares of Stock purchased
upon the exercise of rights under the Plan prior to fulfillment of all of the
following conditions:

         (a) The admission of such shares to listing on all stock exchanges, if
any, on which the Stock is then listed; and

         (b) The completion of any registration or other qualification of such
shares under any state or federal law or under the rulings or regulations of the
Securities and Exchange Commission or any other governmental regulatory body,
which the Administrator shall, in its absolute discretion, deem necessary or
advisable; and

         (c) The obtaining of any approval or other clearance from any state or
federal governmental agency which the Administrator shall, in its absolute
discretion, determine to be necessary or advisable; and

         (d) The payment to the Company of all amounts which it is required to
withhold under federal, state or local law upon exercise of the rights, if any;
and

         (e) The lapse of such reasonable period of time following the exercise
of the rights as the Administrator may from time to time establish for reasons
of administrative convenience.

                                  ARTICLE VIII

              WITHDRAWAL; TERMINATION OF EMPLOYMENT OR ELIGIBILITY

      8.1 Withdrawal. A Participant may withdraw all but not less than all of
the payroll deductions credited to his or her account and not yet used to
exercise his or her rights under the Plan at any time by giving written notice
to the Company in a form acceptable to the Administrator. All of the
Participant's payroll deductions credited to his or her account during the
Offering Period shall be paid to such Participant as soon as reasonably
practicable after receipt of notice of withdrawal and such Participant's rights
for the Offering Period shall be automatically terminated, and no further
payroll deductions for the purchase of shares shall be made for such Offering
Period. If a Participant withdraws from an Offering Period, payroll deductions
shall not resume at the beginning of the next Offering Period unless the
Participant delivers to the Company a new participation agreement.

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      8.2 Future Participation. A Participant's withdrawal from an Offering
Period shall not have any effect upon his or her eligibility to participate in
any similar plan which may hereafter be adopted by the Company or a Designated
Subsidiary or in subsequent Offering Periods which commence after the
termination of the Offering Period from which the Participant withdraws.

      8.3 Cessation of Eligibility. Upon a Participant's ceasing to be an
Eligible Employee, for any reason, he or she shall be deemed to have elected to
withdraw from the Plan pursuant to this Article 8 and the payroll deductions
credited to such Participant's account during the Offering Period shall be paid
to such Participant or, in the case of his or her death, to the person or
persons entitled thereto under 13.4, as soon as reasonably practicable and such
Participant's rights for the Offering Period shall be automatically terminated.

                                   ARTICLE IX

                        ADJUSTMENTS UPON CHANGES IN STOCK

      9.1 Changes in Capitalization. Subject to Section 9.3, in the event of any
stock dividend, stock split, combination or exchange of shares, merger,
consolidation, spin-off, recapitalization, distribution of Company assets to
stockholders (other than normal cash dividends), or any other corporate event
affecting the Stock or the share price of the Stock, the Administrator may make
such proportionate adjustments, if any, as the Administrator in its discretion
may deem appropriate to reflect such change with respect to (i) the aggregate
number and type of shares of Stock (or other securities or property) that may be
issued under the Plan (including, but not limited to, adjustments of the
limitations in Section 3.1 and the limitations established in each Offering
Document pursuant to Section 5.2 on the maximum number of shares of Stock that
may be purchased); (ii) the class(es) and number of shares and price per share
of Stock subject to outstanding rights; and (iii) the Purchase Price with
respect to any outstanding rights.

      9.2 Other Adjustments. Subject to Section 9.3, in the event of any
transaction or event described in Section 9.1 or any unusual or nonrecurring
transactions or events affecting the Company, any affiliate of the Company, or
the financial statements of the Company or any affiliate (including without
limitation any Change in Control), or of changes in applicable laws, regulations
or accounting principles, and whenever the Administrator determines that such
action is appropriate in order to prevent the dilution or enlargement of the
benefits or potential benefits intended to be made available under the Plan or
with respect to any right under the Plan, to facilitate such transactions or
events or to give effect to such changes in laws, regulations or principles, the
Administrator, in its sole discretion and on such terms and conditions as it
deems appropriate, is hereby authorized to take any one or more of the following
actions:

         (a) To provide for either (i) termination of any outstanding right in
exchange for an amount of cash, if any, equal to the amount that would have been
obtained upon the exercise of such right had such right been currently
exercisable or (ii) the replacement of such outstanding right with other rights
or property selected by the Administrator in its sole discretion;

         (b) To provide that the outstanding rights under the Plan be assumed by
the successor or survivor corporation, or a parent or subsidiary thereof, or
shall be substituted for by similar rights covering the stock of the successor
or survivor corporation, or a parent or subsidiary thereof, with appropriate
adjustments as to the number and kind of shares and prices; and

         (c) To make adjustments in the number and type of shares of Stock (or
other securities or property) subject to outstanding rights under the Plan
and/or in the terms and conditions of outstanding rights and rights which may be
granted in the future;

                                       10

<PAGE>

         (d) To provide that Participants' accumulated payroll deductions may be
used to purchase Stock prior to the next occurring Purchase Date on such date as
the Administrator determines in its sole discretion and the Participants' rights
under the ongoing Offering Period(s) terminated; and

         (e) To provide that all outstanding rights shall terminate without
being exercised.

      9.3 No Adjustment Under Certain Circumstances. No adjustment or action
described in this Article 9 or in any other provision of the Plan shall be
authorized to the extent that such adjustment or action would cause the Plan to
fail to satisfy the requirements of Section 423 of the Code.

      9.4 No Other Rights. Except as expressly provided in the Plan, no
Participant shall have any rights by reason of any subdivision or consolidation
of shares of stock of any class, the payment of any dividend, any increase or
decrease in the number of shares of stock of any class or any dissolution,
liquidation, merger, or consolidation of the Company or any other corporation.
Except as expressly provided in the Plan or pursuant to action of the
Administrator under the Plan, no issuance by the Company of shares of stock of
any class, or securities convertible into shares of stock of any class, shall
affect, and no adjustment by reason thereof shall be made with respect to, the
number of shares of Stock subject to an Award or the grant or exercise price of
any Award.

                                   ARTICLE X

                     AMENDMENT, MODIFICATION AND TERMINATION

      10.1 Amendment, Modification and Termination. The Administrator may amend,
suspend or terminate the Plan at any time and from time to time; provided,
however, that approval by a vote of the holders of the outstanding shares of the
Company's capital stock entitled to vote shall be required to amend the Plan to:
(a) change the aggregate number of shares that may be sold pursuant to rights
under the Plan under Section 4.1 (other than any adjustment as provided by
Article 9); (b) change the corporations or classes of corporations whose
employees may be granted rights under the Plan; or (c) change the Plan in any
manner that would cause the Plan to no longer be an "employee stock purchase
plan" within the meaning of Section 423(b) of the Code.

      10.2 Rights Previously Granted. Except as provided in Article 9 or this
Article 10, no termination, amendment or modification may make any change in any
right theretofore granted which adversely affects the rights of any Participant
without the consent of such Participant, provided that an Offering Period may be
terminated, amended or modified by the Administrator if the Administrator
determines that the termination of the Offering Period or the Plan is in the
best interests of the Company and its stockholders.

      10.3 Certain Changes to Plan. Without stockholder consent and without
regard to whether any Participant rights may be considered to have been
adversely affected, to the extent permitted by Section 423 of the Code, the
Administrator shall be entitled to change the Offering Periods, limit the
frequency and/or number of changes in the amount withheld during an Offering
Period, establish the exchange ratio applicable to amounts withheld in a
currency other than U.S. dollars, permit payroll withholding in excess of the
amount designated by a Participant in order to adjust for delays or mistakes in
the Company's processing of properly completed withholding elections, establish
reasonable waiting and adjustment periods and/or accounting and crediting
procedures to ensure that amounts applied toward the purchase of Stock for each
Participant properly correspond with amounts withheld from the Participant's
Compensation, and establish such other limitations or procedures as the
Administrator determines in its sole discretion advisable which are consistent
with the Plan.

                                       11

<PAGE>

                                   ARTICLE XI

                                  TERM OF PLAN

      The Plan shall be effective on the date the Plan is first adopted by the
Board (the "EFFECTIVE DATE"). The effectiveness of the Plan shall be subject to
approval of the Plan by the stockholders of the Company in accordance with this
Article 11. The Plan shall be in effect until the tenth anniversary of the
Effective Date, unless sooner terminated under Article 10. No rights may be
granted under the Plan during any period of suspension of the Plan or after
termination of the Plan. The Plan shall be submitted for the approval of the
Company's stockholders within twelve months after the Effective Date. No right
may be granted under the Plan prior to such stockholder approval.

                                  ARTICLE XII

                                  MISCELLANEOUS

      12.1 Restriction upon Assignment. A right granted under the Plan shall not
be transferable other than by will or the laws of descent and distribution, and
is exercisable during the Participant's lifetime only by the Participant. Except
as provided in Section 12.4 hereof, a right under the Plan may not be exercised
to any extent except by the Participant. The Company shall not recognize and
shall be under no duty to recognize any assignment or alienation of the
Participant's interest in the Plan, the Participant's rights under the Plan or
any rights thereunder.

      12.2 Rights as a Stockholder. With respect to shares of Stock subject to a
right granted under the Plan, a Participant shall not be deemed to be a
stockholder of the Company, and the Participant shall not have any of the rights
or privileges of a stockholder, until such shares have been issued to the
Participant or his or her nominee following exercise of the Participant's rights
under the Plan. No adjustments shall be made for dividends (ordinary or
extraordinary, whether in cash securities, or other property) or distribution or
other rights for which the record date occurs prior to the date of such
issuance, except as otherwise expressly provided herein.

      12.3 Interest. No interest shall accrue on the payroll deductions or lump
sum contributions of a Participant under the Plan.

      12.4 Designation of Beneficiary.

         (a) A Participant may, in the manner determined by the Administrator,
file a written designation of a beneficiary who is to receive any shares and
cash, if any, from the Participant's account under the Plan in the event of such
Participant's death subsequent to a Purchase Date on which the Participant's
rights are exercised but prior to delivery to such Participant of such shares
and cash. In addition, a Participant may file a written designation of a
beneficiary who is to receive any cash from the Participant's account under the
Plan in the event of such Participant's death prior to exercise of the
Participant's rights under the Plan. If the Participant is married and resides
in a community property state, a designation of a person other than the
Participant's spouse as his or her beneficiary shall not be effective without
the prior written consent of the Participant's spouse.

                                       12

<PAGE>

         (b) Such designation of beneficiary may be changed by the Participant
at any time by written notice to the Company. In the event of the death of a
Participant and in the absence of a beneficiary validly designated under the
Plan who is living at the time of such Participant's death, the Company shall
deliver such shares and/or cash to the executor or administrator of the estate
of the Participant, or if no such executor or administrator has been appointed
(to the knowledge of the Company), the Company, in its discretion, may deliver
such shares and/or cash to the spouse or to any one or more dependents or
relatives of the Participant, or if no spouse, dependent or relative is known to
the Company, then to such other person as the Company may designate.

      12.5 Notices. All notices or other communications by a Participant to the
Company under or in connection with the Plan shall be deemed to have been duly
given when received in the form specified by the Company at the location, or by
the person, designated by the Company for the receipt thereof.

      12.6 Equal Rights and Privileges. All Eligible Employees of the Company or
any Designated Subsidiary will have equal rights and privileges under this Plan
so that this Plan qualifies as an "employee stock purchase plan" within the
meaning of Section 423 of the Code. Any provision of this Plan that is
inconsistent with Section 423 of the Code will, without further act or amendment
by the Company, the Board or the Administrator, be reformed to comply with the
equal rights and privileges requirement of Section 423 of the Code.

      12.7 Use of Funds. All payroll deductions received or held by the Company
under the Plan may be used by the Company for any corporate purpose, and the
Company shall not be obligated to segregate such payroll deductions.

      12.8 Reports. Statements of account shall be given to participating
Employees at least annually, which statements shall set forth the amounts of
payroll deductions, the Purchase Price, the number of shares purchased and the
remaining cash balance, if any.

      12.9 No Employment Rights. Nothing in the Plan shall be construed to give
any person (including any Eligible Employee or Participant) the right to remain
in the employ of the Company or any Parent or Subsidiary or to affect the right
of the Company or any Parent or Subsidiary to terminate the employment of any
person (including any Eligible Employee or Participant) at any time, with or
without cause.

      12.10 Notice of Disposition of Shares. Each Participant shall give prompt
notice to the Company of any disposition or other transfer of any shares of
stock purchased upon exercise of a right under the Plan if such disposition or
transfer is made: (a) within two years from the Enrollment Date of the Offering
Period in which the shares were purchased or (b) within one year after the
Purchase Date on which such shares were purchased. Such notice shall specify the
date of such disposition or other transfer and the amount realized, in cash,
other property, assumption of indebtedness or other consideration, by the
Participant in such disposition or other transfer.

      12.11 Governing Law. The validity and enforceability of this Plan shall be
governed by and construed in accordance with the laws of the State of California
without regard to otherwise governing principles of conflicts of law.

                                       13
<PAGE>
                               OFFERING DOCUMENT

                                   ----------

                          SOMAXON PHARMACEUTICALS, INC.
                          EMPLOYEE STOCK PURCHASE PLAN

This document (this "OFFERING DOCUMENT") is hereby adopted by the Compensation
Committee of the Board of Directors of Somaxon Pharmaceuticals, Inc., a Delaware
corporation (the "COMPANY"), in its capacity as Administrator of the Somaxon
Pharmaceuticals, Inc. Employee Stock Purchase Plan (the "PLAN"). This Offering
Document is adopted pursuant to Article 5 of the Plan and is hereby incorporated
by reference into and made a part of the Plan. A copy of this Offering Document
shall be attached to the Plan. Defined terms used herein without definition
shall have the meanings specified in the Plan, except as otherwise provided
herein.

This Offering Document shall apply with respect to Offering Periods under the
Plan until this Offering Document is terminated, amended or modified by the
Administrator or a new Offering Document is adopted by the Administrator.


<TABLE>
<CAPTION>
<S>                                             <C>
LENGTH OF OFFERING PERIODS:                     Six months

                                                However, the initial Offering Period under the Plan (the
                                                "INITIAL OFFERING PERIOD") shall commence on the date on
                                                which the Company's registration statement on Form S-8
                                                filed with respect to the Plan becomes effective (such
                                                date, the "INITIAL ENROLLMENT DATE") and shall end on
                                                the first occurring May 31 or November 30 thereafter.

OFFERING PERIODS
WILL COMMENCE ON EACH:                          June 1 and December 1

PURCHASE DATES WILL OCCUR ON EACH:              May 31 and November 30

MAXIMUM NUMBER OF SHARES OF STOCK
THAT MAY BE PURCHASED BY ANY
ELIGIBLE EMPLOYEE DURING AN
OFFERING PERIOD:                                10,000 shares

                                                The maximum aggregate number of shares of Stock that may be
                                                purchased by all Eligible Employees during an Offering Period
                                                is the total number of shares of Stock that are reserved for
                                                issuance under the Plan as of the Enrollment Date for such
                                                Offering Period.

PURCHASE PRICE:                                 On each Purchase Date, the purchase price for a share of common
                                                stock will be 95% of the Fair Market Value per share of the Stock
                                                on the Purchase Date.

CONTRIBUTIONS:                                  A Participant may elect to have up to 20% of his or her
                                                "Compensation" deducted on each payday on an after-tax basis for use in
                                                purchasing Stock pursuant to the Plan.
</TABLE>
                                       1
<PAGE>
<TABLE>
<CAPTION>
<S>                                             <C>
INCREASES/DECREASES IN CONTRIBUTION RATES:      Participants may increase or decrease their rate of
                                                contributions effective as of the first day of each
                                                Offering Period.  Any such change must be made at
                                                least ten days prior to the first day of such
                                                Offering Period.  In addition, Participants may
                                                decrease to 0% their rate of contributions at any
                                                time during each Offering Period.

SPECIAL ENROLLMENT PROVISIONS FOR INITIAL
OFFERING PERIOD ONLY:                           Each Eligible Employee who is employed by the
                                                Company or a Designated Subsidiary on the calendar
                                                day immediately preceding the Initial Enrollment
                                                Date shall automatically become a Participant in
                                                the Plan with respect to the Initial Offering
                                                Period.  Each such Participant shall be granted a
                                                right to purchase shares of Stock and shall be
                                                enrolled in such Initial Offering Period to the
                                                extent of 20% of his or her Compensation for the
                                                paydays during the Initial Offering Period (or, if
                                                less, the maximum amount of contributions permitted
                                                to be made by such Participant for such Offering
                                                Period by payroll deduction under the terms of this
                                                Plan).  Following the Initial Enrollment Date, each
                                                such Participant may, during the period designated
                                                from time to time by the Administrator for such
                                                purpose, (i) elect to make such contributions (or a
                                                lesser amount of contributions) for the Initial
                                                Offering Period by payroll deductions in accordance
                                                with Article 6 of the Plan, (ii) elect to make such
                                                contributions (or a lesser amount of contributions)
                                                for the Initial Offering Period by making a lump
                                                sum cash payment to the Company not later than ten
                                                calendar days before the last day of such Offering
                                                Period, and each such payment may be made in an
                                                amount not exceeding 20% of such Participant's
                                                Compensation for the paydays occurring during such
                                                Offering Period and occurring prior to such lump
                                                sum payment, or (iii) elect to make no
                                                contributions for such Offering Period; provided,
                                                however, that, to make contributions by payroll
                                                deductions, such Participant must complete the form
                                                of participation agreement provided by the Company
                                                for the Initial Offering Period under this Plan
                                                during the time designated by the Administrator for
                                                such purpose.  If (i) during the initial Offering
                                                Period, such a Participant elects to make
                                                contributions by payroll deduction, or elects to
                                                make no contributions for such Offering Period, or
                                                (ii) on or prior to the tenth calendar day before
                                                the last day of such Offering Period, such a
                                                Participant fails to make any lump sum cash
                                                payment, such Participant shall be deemed to have
                                                elected not to make contributions by lump sum
                                                payment with respect to the Initial Offering Period.
</TABLE>


                                       2