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                                                                   Exhibit 10.74



                           SEQUANA THERAPEUTICS, INC.

                              AMENDED AND RESTATED

                       RESTRICTED STOCK PURCHASE AGREEMENT

        THIS AMENDED AND RESTATED RESTRICTED STOCK PURCHASE AGREEMENT (the
"Agreement") is made this 7th day of January, 1998 between SEQUANA THERAPEUTICS,
INC., a California corporation (the "Company"), and KEVIN J. KINSELLA (the
"Purchaser" ) .

        WHEREAS the Company and the Purchaser are parties to that certain
Restricted Stock Purchase Agreement dated as of March 3, 1995 (the "Original
Agreement"), pursuant to which the parties agreed to certain rights and
restrictions with respect to shares of the company's common stock;

        WHEREAS, pursuant to the Original Agreement the Company sold to the
Purchaser and the Purchaser purchased an aggregate of 2,500,000 shares of the
company's common stock (the "Shares"), at the price of $0.075 per share for an
aggregate purchase price of $187,500.00;

        WHEREAS, the purchase price for the Shares was paid by delivery to the
Company at the time of execution of the Original Agreement of a check or a duly
executed full recourse promissory note (the "Note");

        WHEREAS, the parties desire to amend and restate the Original Agreement
as set forth herein.

        NOW, THEREFORE, the parties hereto agree as follows:

        1.     THE NOTE

         With respect to the Note, the parties agree to the following:

               (a) The Note shall become payable in full ninety (90) days
following the termination or cessation of the Purchaser's employment with or
services to the Company for any reason.

               (b) The Purchaser shall deliver to an escrow holder designated by
the Company (the "Escrow Holder") all certificates representing the Shares and
an executed blank stock assignment for use in transferring all or a portion of
said Shares to the Company if, as and when required under this Section 2(b) or
under any other provision of this Agreement including Section 3.

               (c) As security for the payment of the Note and any renewal,
extension or modification thereof, the Purchaser hereby grants to the Company a
security interest in and pledges with and delivers to the Company the
certificate or certificates representing the Shares.

               (d) In the event of any foreclosure of the security interest, the
Company may sell the Shares at a private sale or may itself repurchase any or
all of the Shares. The parties


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acknowledge that, prior to the establishment of a public market for the Shares
of the Company, the securities laws applicable to the sale of the Shares make a
public sale of the Shares commercially unreasonable. The parties agree that the
repurchasing of said Shares by the Company, or by any person to whom the Company
may have assigned its rights hereunder, is commercially reasonable if made at a
price determined by the Board of Directors in its discretion, fairly exercised,
representing what would be the fair market value of the Shares diminished by any
limitation on transferability, whether due to the size of the block of Shares or
the restrictions of applicable securities laws.

               (e) In the event of default in payment when due of any
indebtedness under the Note, the Company may elect then, or at any time
thereafter, to exercise all rights available to a secured party under the
California Commercial Code, including the right to sell the Shares at a private
or public sale or repurchase the Shares as provided above. The proceeds of any
sale shall be applied in the following order:

                      (i) To pay all reasonable expenses of the Company in
enforcing this Agreement, including without limitation reasonable attorneys'
fees and legal expenses incurred by the Company.

                      (ii) In satisfaction of the remaining indebtedness under
the Note.

                      (iii) To the Purchaser, any remaining proceeds.

               (f) Upon full payment by the Purchaser of all amounts due on
Purchaser's Note, the Escrow Holder shall deliver to the Purchaser the
certificate or certificates representing the Shares in the Escrow Holder's
possession belonging to the Purchaser, the blank stock assignment, and the
executed original of the Note marked "cancelled" by the Company, and the Escrow
Holder shall be discharged of all further obligations hereunder; provided,
however, that the Escrow Holder shall nevertheless retain said certificate or
certificates and stock assignment as escrow agent if so required pursuant to
other restrictions imposed pursuant to this Agreement.

        2.     REPURCHASE OPTION.

               (a) In the event of any voluntary or involuntary termination of
the Purchaser's employment by or services to the Company for any or no reason
(but not including termination as a result of death or disability, and not in
the event that Purchaser is (i) performing consulting services for the Company,
or remains available to perform such services pursuant to the terms of a written
consulting agreement, or (ii) is a director of the Company or any successor
entity, including an entity into which the Company merges or which acquires
(directly or through its Purchasers) more than 50% of the outstanding voting
capital stock of the Company) before all of the Shares are released from the
Company's repurchase option (see Section 4), the Company shall, upon the date of
such termination (as reasonably fixed and determined by the Company) have an
irrevocable, exclusive option for a period of ninety (90) days from such date to
repurchase all (but not less than all) of the Unreleased Shares (as defined in
Section 3) at such time at the original purchase price per share (the
"Repurchase Price")."

               (b) Whenever the Company shall have the right to repurchase
Shares hereunder, the Company may designate and assign one or more employees,
officers, directors or



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shareholders of the Company or other persons or organizations to exercise all or
a part of the Company's purchase rights under this Agreement and purchase all or
a part of such Shares; provided that if the fair market value of the Shares to
be repurchased on the date of such designation or assignment (the "Repurchase
FMV") exceeds the Repurchase Price of the Shares to be repurchased, then each
such designee or assignee shall pay the Company cash equal to the difference
between the Repurchase FMV and the Repurchase Price of the Shares which such
designee or assignee shall have the right to repurchase.

        3.     RELEASE OF SHARES FROM REPURCHASE OPTION.

               (a) One forty-eighth (1/48) of the Shares shall be released from
the Company's repurchase option on the first day of each calendar month
commencing February 1, 1995, provided in each case that the Purchaser's
employment or services have not been terminated prior to the date of any such
release.

               (b) In the event the Purchaser dies or becomes disabled, all of
the Shares subject to this Agreement shall be released from the Company's
repurchase option.

               (c) Any of the Shares which have not yet been released from the
Company's repurchase option are referred to herein as "Unreleased Shares."

               (d) The Shares which (i) have been released from the Company's
repurchase option, (ii) have been paid for in full, and (iii) no longer secure
Shares not yet paid for in full shall be delivered to the Purchaser at the
Purchaser's request (see Section 5).

        4. RESTRICTION ON TRANSFER. Except for the pledge and escrow described
in Sections 1 and 5 or transfer of the Shares to the Company or its assignees
contemplated by this Agreement, none of the Shares or any beneficial interest
therein shall be transferred, encumbered or otherwise disposed of in any way
until the release of such Shares from the Company's repurchase option in
accordance with the provisions of this Agreement, other than by will or the laws
of descent and distribution.

        5.     ESCROW OF SHARES.

               (a) The Shares issued under this Agreement shall be held by the
Escrow Holder, along with a stock assignment executed by the Purchaser in blank,
until the expiration of the Company's option to repurchase such Shares as set
forth above.

               (b) The Escrow Holder is hereby directed to permit transfer of
the Shares only in accordance with this Agreement or instructions signed by both
parties. In the event further instructions are desired by the Escrow Holder, the
Escrow Holder shall be entitled to rely upon directions executed by a majority
of the authorized number of the Company's Board of Directors. The Escrow Holder
shall have no liability for any act or omission hereunder while acting in good
faith in the exercise of the Escrow Holder's own judgment.

               (c) If the Company or any assignee exercises its repurchase
option hereunder, the Escrow Holder, upon receipt of written notice of such
option exercise from the proposed transferee, shall take all steps necessary to
accomplish such transfer.



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               (d) When the repurchase option has been exercised or expires
unexercised or a portion of the Shares has been released from such repurchase
option and provided the Note has been paid in full, upon Purchaser's request the
Escrow Holder shall promptly cause a new certificate to be issued for such
released Shares and shall deliver such certificate to the Purchaser.

               (e) Subject to the terms hereof, the Purchaser shall have all the
rights of a shareholder with respect to such Shares while they are held in
escrow, including without limitation, the right to vote the Shares and receive
any cash dividends declared thereon. If, from time to time during the term of
the Company's repurchase option, there is (i) any stock dividend, stock split or
other change in the Shares, or (ii) any merger or sale of all or substantially
all of the assets or other acquisition of the Company, any and all new,
substituted or additional securities to which the Purchaser is entitled by
reason of the Purchaser's ownership of the Shares shall be immediately subject
to this escrow, deposited with the Escrow Holder and included thereafter as
"Shares" for purposes of this Agreement and the Company's repurchase option.

        6.     INVESTMENT REPRESENTATIONS: RESTRICTIONS ON TRANSFER.

               (a) In connection with the purchase of the Shares, the Purchaser
represents to the Company the following:

                      (i) The Purchaser is aware of the Company's business
affairs and financial condition and has acquired sufficient information about
the Company to reach an informed and knowledgeable decision to acquire the
Shares. The Purchaser is purchasing these Shares for investment for the
Purchaser's own account only and not with a view to, or for resale in connection
with, any "distribution" thereof within the meaning of the Securities Act of
1933, as amended (the "Securities Act").

                      (ii) The Purchaser acknowledges and understands that the
Shares constitute "restricted securities" under the Securities Act and must be
held indefinitely unless they are subsequently registered under the Securities
Act or an exemption from such registration is available. The Purchaser further
acknowledges and understands that the Company is under no obligation to register
the Shares. The Purchaser understands that the certificate evidencing the Shares
will be imprinted with a legend which prohibits the transfer of the Shares
unless they are registered or such registration is not required in the opinion
of counsel satisfactory to the Company.

                      (iii) The Purchaser is familiar with the provisions of
Rule 701 and Rule 144, each promulgated under the Securities Act, which, in
substance, permit limited public resale of "restricted securities" acquired,
directly or indirectly, from the issuer thereof, in a non-public offering
subject to the satisfaction of certain conditions. Rule 701 provides that if the
issuer qualifies under Rule 701 at the time of issuance of the securities to the
Purchaser, such issuance will be exempt from registration under the Securities
Act. In the event the Company later becomes subject to the reporting
requirements of Section 13 or 15(d) of the Securities Exchange Act of 1934,
ninety (90) days thereafter the securities exempt under Rule 701 may be resold,
subject to the satisfaction of certain of the conditions specified by Rule 144,
including among other things: (1) the sale being made through a broker in an
unsolicited "broker's transaction" or



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in transactions directly with a market maker (as said term is defined under the
Securities Exchange Act of 1934); and, in the case of an affiliate, (2) the
availability of certain public information about the Company, and the amount of
securities being sold during any three month period not exceeding the
limitations specified in Rule 144(e), if applicable. Notwithstanding this
paragraph 7(a) (iii), the Purchaser acknowledges and agrees to the restrictions
set forth in paragraph 7(b).

        In the event that the Company does not qualify under Rule 701 at the
time of issuance of the securities to the Purchaser, then the securities may be
resold in certain limited circumstances subject to the provisions of Rule 144,
which requires among other things: (1) the availability of certain public
information about the Company: (2) the resale occurring not less than two years
after the party has purchased, and made full payment for, within the meaning of
Rule 144, the securities to be sold; and (3) in the case of an affiliate, or of
a non-affiliate who has held the securities less than three years, the sale
being made through a broker in an unsolicited "broker's transaction" or in
transactions directly with a market maker (as said term is defined under the
Securities Exchange Act of 1934) and the amount of securities being sold during
any three month period not exceeding the specified limitations stated therein,
if applicable.

               (b) The Purchaser agrees, in connection with the Company's
initial underwritten public offering of the Company's securities, (1) not to
sell, make short sale of, loan, grant any options for the purchase of, or
otherwise dispose of any shares of Common Stock of the Company held by the
Purchaser (other than those shares included in the registration) without the
prior written consent of the Company or the underwriters managing such initial
underwritten public offering of the Company's securities for one hundred eighty
(180) days from the effective date of such registration, and (2) further agrees
to execute any agreement reflecting (1) above as may be requested by the
underwriters at the time of the public offering.

        7. LEGENDS. The share certificate evidencing the Shares issued hereunder
shall be endorsed with the following legends (in addition to any legends
required under applicable state securities laws ):

               (a) IT IS UNLAWFUL TO CONSUMMATE A SALE OR TRANSFER OF THIS
SECURITY, OR ANY INTEREST THEREIN, OR TO RECEIVE ANY CONSIDERATION THEREFOR,
WITHOUT THE PRIOR WRITTEN CONSENT OF THE CALIFORNIA COMMISSIONER OF CORPORATIONS
EXCEPT AS PERMITTED IN THE COMMISSIONER'S RULES.

               (b) THE SHARES REPRESENTED BY THIS CERTIFICATE RAVE BEEN ACQUIRED
FOR INVESTMENT AND NOT WITH A VIEW TO, OR IN CONNECTION WITH, THE SALE OR
DISTRIBUTION THEREOF. NO SUCH SALE OR DISPOSITION MAY BE EFFECTED WITHOUT AN
EFFECTIVE REGISTRATION STATEMENT RELATED THERETO OR AN OPINION OF COUNSEL
SATISFACTORY TO THE COMPANY THAT SUCH REGISTRATION IS NOT REQUIRED UNDER THE
SECURITIES ACT OF 1933.

               (c) THE SHARES REPRESENTED BY THIS CERTIFICATE MAY BE TRANSFERRED
ONLY IN ACCORDANCE WITH THE TERMS OF AN AGREEMENT



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BETWEEN THE COMPANY AND THE SHAREHOLDER, A COPY OF WHICH IS ON FILE WITH THE
SECRETARY OF THE COMPANY.

        8. ADJUSTMENT FOR STOCK SPLIT. All references to the number of Shares
and the purchase price of the Shares in this Agreement shall be appropriately
adjusted to reflect any stock split, stock dividend or other change in the
Shares which may be made by the Company after the date of this Agreement.

        9. TAX CONSEQUENCES. The Purchaser has reviewed with the Purchaser's own
tax advisors the federal, state, local and foreign tax consequences of this
investment and the transactions contemplated by this Agreement. The Purchaser is
relying solely on such advisors and not on any statements or representations of
the Company or any of its agents. The Purchaser understands that the Purchaser
(and not the Company) shall be responsible for the Purchaser's own tax liability
that may arise as a result of this investment or the transactions contemplated
by this Agreement. The Purchaser understands that Section 83 of the Internal
Revenue Code of 1986 (the "Code"), taxes as ordinary income both (i) the
difference between the fair market value of the Shares when the Company granted
the Purchaser the right to purchase the Shares and the fair market value of the
Shares on the date of this Agreement and (ii) the difference between the amount
paid for the Shares and the fair market value of the Shares as of the date any
restrictions on the Shares lapse. In this context, "restriction" includes the
right of the Company to buy back the Shares pursuant to its repurchase option.
In the event the Company has registered under the Exchange Act, "restriction"
with respect to officers, directors and 10% shareholders also means the period
after the purchase of the Shares during which such officers, directors and 10%
shareholders could be subject to suit under Section 16(b) of the Exchange Act.
The Purchaser understands that the Purchaser may elect to be taxed at the time
the Shares are purchased rather than when and as the Company's repurchase option
or 16(b) period expires by filing an election under Section 83(b) of the Code
with the I.R.S. within 30 days from the date of purchase.

        THE PURCHASER ACKNOWLEDGES THAT IT IS THE PURCHASER'S SOLE
RESPONSIBILITY AND NOT THE COMPANY'S TO FILE TIMELY THE ELECTION UNDER SECTION
83 (b), EVEN IF THE PURCHASER REQUESTS THE COMPANY OR ITS REPRESENTATIVES TO
MAKE THIS FILING ON THE PURCHASER' S BEHALF.

        10.    GENERAL PROVISIONS.

               (a) This Agreement shall be governed by the laws of the State of
California as they apply to contracts entered into and wholly to be performed in
such state. This Agreement represents the entire agreement between the parties
with respect to the purchase of Common Stock by the Purchaser and may only be
modified or amended in writing signed by both parties.

               (b) Any notice, demand or request required or permitted to be
given by either the Company or the Purchaser pursuant to the terms of this
Agreement shall be in writing and shall be deemed given when delivered
personally or deposited in the U.S. mail, First Class with postage prepaid, and
addressed to the parties at the addresses of the parties set forth at the end of
this Agreement or such other address as a party may request by notifying the
other in writing.



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               (c) Any notice to the Escrow Holder shall be sent to the
Company's address with a copy to the other party not sending the notice.

               (d) The rights and benefits of the Company under this Agreement
shall be transferable to any one or more persons or entities, and all covenants
and agreements hereunder shall inure to the benefit of, and be enforceable by
the Company's successors and assigns. The rights and obligations of the
Purchaser under this Agreement may only be assigned with the prior written
consent of the Company.

               (e) Either party's failure to enforce any provision or provisions
of this Agreement shall not in any way be construed as a waiver of any such
provision or provisions, nor prevent that party thereafter from enforcing each
and every other provision of this Agreement. The rights granted both parties
herein are cumulative and shall not constitute a waiver of either party's right
to assert all other legal remedies available to it under the circumstances.

               (f) The Purchaser agrees Upon request to execute any further
documents or instruments necessary or desirable to carry out the purposes or
intent of this Agreement.

               (g) PURCHASER ACKNOWLEDGES AND AGREES THAT THE VESTING OF SHARES
PURSUANT TO SECTION 3 HEREOF IS EARNED ONLY BY CONTINUING SERVICE AS AN EMPLOYEE
OR CONSULTANT AT THE WILL OF THE COMPANY (NOT THROUGH THE ACT OF BEING HIRED OR
PURCHASING SHARES HEREUNDER). PURCHASER FURTHER ACKNOWLEDGES AND AGREES THAT
THIS AGREEMENT, THE TRANSACTIONS CONTEMPLATED HEREUNDER AND THE VESTING SCHEDULE
SET FORTH HEREIN DO NOT CONSTITUTE AN EXPRESS OR IMPLIED PROMISE OF CONTINUED
ENGAGEMENT AS AN EMPLOYEE OR CONSULTANT FOR THE VESTING PERIOD, FOR ANY PERIOD,
OR AT ALL, AND SHALL NOT INTERFERE WITH PURCHASER'S RIGHT OR THE COMPANY'S RIGHT
TO TERMINATE PURCHASER'S EMPLOYMENT OR CONSULTING RELATIONSHIP AT ANYTIME, WITH
OR WITHOUT CAUSE.

               (h) Purchaser acknowledges receipt of a copy of the Plan, a copy
of which is annexed hereto, represents that Purchaser is familiar with the terms
and provisions thereof, and hereby accepts this Agreement subject to all of the
terms and provisions thereof. Purchase has reviewed the Plan and this Agreement
in their entirety, has had an opportunity to obtain the advice of counsel prior
to executing this Agreement and fully understands all provisions of the
Agreement. Purchase hereby agrees to accept as binding, conclusive and final all
decisions or interpretations of the Board or of the Committee upon any questions
arising under the Plan. Purchaser further agrees to notify the Company upon any
change in the residence address indicated below.


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        IN WITNESS WHEREOF, the parties have duly executed this Amended and
Restated Restricted Stock Purchase Agreement as of the day and year first set
forth above.

SEQUANA THERAPEUTICS, INC.              PURCHASER:
a California corporation


By:     /s/  John P. Walker             /s/  Kevin J. Kinsella
   -------------------------------      ---------------------------------
                                        Kevin J. Kinsella
Title:  Chairman                        1735 Castellana Road
      ----------------------------
11099 No. Torrey Pines Road             La Jolla, CA 92037
La Jolla, CA  92037



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