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                                                                   Exhibit 10.52



                              EMPLOYMENT AGREEMENT
                             (Dr. Samuil R. Umansky)

        This Employment Agreement ("Agreement") is made and entered into as of
the 12 day of October, 1998 (the "Effective Date") by and between LXR
Biotechnology Inc. ("LXR"), a Delaware corporation with its principal offices at
1401 Marina Way South, Richmond, CA 94804 and Dr. Samuil R. Umansky
("Executive") residing at 6034 Monterey Avenue, Richmond, CA 94805. This
Agreement supersedes any prior agreement or understanding relating to
Executive's employment with or compensation by LXR.

        LXR desires to appoint the Executive as the Chief Scientific Officer and
Vice President of Molecular Pharmacology of LXR, for the period and upon the
terms and conditions hereinafter set forth.

        Executive desires to serve in such capacities for such period and upon
such terms and conditions hereinafter set forth.

        Accordingly, the parties hereto agree as follows:

        SECTION 1.  EMPLOYMENT OF EXECUTIVE.

        1.1. Employment. Subject to the terms and conditions of this Agreement,
LXR agrees to employ Executive as Chief Scientific Officer and Vice President of
Molecular Pharmacology of LXR. Executive shall have such responsibilities and
shall perform such specific duties as are commensurate with such positions, and
as may reasonably be assigned to the Executive from time to time by the Board of
Directors and/or the President and Chief Executive Officer of LXR, for the
period commencing on the date hereof until terminated as herein provided.
Executive hereby accepts such employment. Executive shall devote all of his
business time, energy, and skill to the affairs of LXR; provided, however, that
reasonable time for personal business, charitable or professional activities
shall be permitted, so long as such activities do not materially interfere with
the Executive's performance of services under this Agreement.



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        SECTION 2. COMPENSATION. For all services to be rendered by Executive to
LXR during the term of this Agreement, LXR shall pay to, and provide the
Executive with, the following compensation and benefits. Except as expressly set
forth in this Section 2, all benefits and amounts payable under this Agreement
shall be subject to, and shall be reduced for, applicable federal, state and
local taxes, and LXR will withhold from payments to Executive all such taxes and
other withholdings subject to withholding obligations.

        2.1. Base Salary and Bonus. For the period beginning January 1, 1998,
LXR shall pay to Executive a base salary of $153,000 per year, payable in
substantially equal biweekly installments in accordance with LXR payroll
practice. In addition, commencing 12 months from January 1, 1998, Executive will
be eligible for an incentive bonus of up to $17,000 to be paid after such 12
month period. The amount of such bonus, if any, shall be determined at the sole
discretion of LXR and shall be payable within 60 days after such 12 month
period. Such bonus, if any, shall be pro-rated for any partial year and shall be
based upon, among other things, performance of the Company and other factors
established at the sole discretion of the Board of Directors and/or the
Compensation Committee. LXR will review Executive's base salary and bonus from
time to time and may make adjustments to such base salary and determine such
bonus based upon, among other factors: (a) Executive's performance, (b) LXR's
performance, (c) changes in costs of living, (d) changes in Executive's
responsibilities, and (e) the benefit to LXR of Executive's efforts on its
behalf; provided that Executive's base salary shall not be less than $153,000
per year during the term of this Agreement.

        2.2. Initial and Subsequent Option Grants. As of the effective date of
the agreement, the Executive has been granted Stock Options pursuant to the
terms and conditions of, LXR's 1993 Stock Option Plan (the "Plan"), as listed in
Exhibit A. From time to time at the sole discretion of the Board of Directors,
LXR may grant Executive additional stock options under LXR's stock option plans.

        2.3. Participation in Benefit Plans. Executive shall be entitled to
immediate participation in all employee benefit plans or programs of LXR,
subject to eligibility requirements required by law or the written provisions of
any such plans or programs. LXR does not guarantee the adoption or continuance
of any particular employee benefit or stock plan or other program during the
term of this Agreement, and Executive's participation in any such plan or
program shall be subject to provisions, rules and regulations applicable
thereto. Executive shall be entitled to paid vacation each year in an amount
available to other senior executive officers and in accordance with applicable
LXR policy. Health and dental plans available to Executive pursuant to this
Section 2.3 shall be available to the Executive and his eligible dependents.



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        2.4. Expense Reimbursement. LXR shall reimburse Executive for all
ordinary, reasonable and necessary business expenses incurred in the performance
of Executive's duties under this Agreement, in accordance with LXR's policies
and practices, provided that Executive accounts properly for such expenses to
LXR in accordance with the general corporate policies of LXR and in accordance
with the requirements of the Internal Revenue Service regulations relating to
substantiation of expenses.

        SECTION 3. INTELLECTUAL PROPERTY AND CONFIDENTIAL INFORMATION AGREEMENT.
As a condition to LXR's obligations hereunder, the Executive is bound by the
Intellectual Property and Confidential Information Agreement entered into with
the Company and attached hereto as Exhibit B.

        The obligations of Executive under this section and the agreements
referenced in the preceding paragraph shall survive termination of this
Agreement for any reason.

        SECTION 4. TERMINATION AND SEVERANCE PAYMENT.

        4.1. Termination. The employment of the Executive by LXR is "at will"
and may be terminated as follows:

               (a) Executive's employment hereunder shall terminate upon
Executive's death, or his failure or inability by reason of physical or mental
impairment to perform substantially all of Executive's duties as contemplated
herein for a continuous period of 120 days or more.

               (b) Executive's employment hereunder may be terminated by LXR or
Executive for any reason and without cause (hereinafter, termination pursuant to
this Section 4.1(b) is referred to as "Termination Without Cause"). A
substantial reduction of the responsibilities of Executive, including but not
limited to removal of the Executive as the Chief Scientific Officer of LXR
except for the reasons specified in Section 4.1(c), shall be deemed a
Termination Without Cause by LXR.

               (c) Executive's employment hereunder may be terminated by LXR in
the event of Executive's breach of any material duty or obligation hereunder, or
any established policy of LXR applicable to other executive officers,
intentional or grossly negligent conduct that is materially injurious to LXR,
failure to follow the reasonable directions of LXR's Board of Directors,
dishonesty of or fraud by Executive, or commission of a crime involving moral
turpitude, in each case as reasonably determined by LXR's Board of Directors
(termination because of any such event is referred to herein as "Termination for
Cause").



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        4.2. Severance Payment; Benefits.

               (a) Termination Events Resulting in Severance Payments. In the
event of the Termination Without Cause by LXR under Section 4.1(b) then LXR
shall make severance payment(s) to Executive equal to six (6) months of the
Executive's base salary as of the date of such termination (the "Base Salary
Payment"). Such severance amount shall be payable in installments in accordance
with LXR's payroll practice.

               (b) Termination Events Not Resulting in Severance. In the event
of the termination of Executive's employment by Executive, or by the Company
pursuant to Section 4.1(c), the Executive shall not be entitled to any further
payments or benefits after the date of such termination.

               (c) Benefits. Executive's coverage under LXR's life, health,
dental insurance plans will remain in effect, at LXR's expense, during the six
(6) month period following Termination Without Cause by LXR, unless Executive
notifies LXR in writing that such coverage is no longer necessary or if
Executive is no longer eligible under COBRA. If, because of limitations required
by third parties or imposed by law, Executive cannot be provided such benefits
through LXR's plans, then LXR will provide Executive with substantially
equivalent benefits on an aggregate basis, at its expense. Executive shall not
be entitled to any further benefits after the date of any termination by
Executive, or after any Termination For Cause.

        4.3. Accelerated Vesting of Options Upon a Change of Control. Vesting of
the Options shall accelerate upon a change in control of LXR in accordance with
the Plan.

        SECTION 5.  MISCELLANEOUS.

        5.1. Assignment. This Agreement may not be assigned, in whole or in
part, by any party without the prior written consent of the other party, except
that LXR may, without the consent of the Executive, assign its rights and
obligations under this Agreement to any corporation, firm or other business
entity with or into which LXR may merge or consolidate, or to which LXR may sell
or transfer all or substantially all of its assets, or of which 50% or more of
the equity investment and of the voting control is owned, directly or
indirectly, by, or is under common ownership with, LXR. After any such
assignment by LXR, LXR shall be discharged from all further liability hereunder
and such assignee shall have all the rights and obligations of LXR under this
Agreement.



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        5.2. Notices. All notices, requests, demands and other communications to
be given pursuant to this Agreement shall be in writing and shall be deemed to
have been duly given if delivered by hand or mailed by registered or certified
mail, return receipt requested, postage prepaid, to the addresses set forth at
the beginning of this Agreement or such other address as a party shall have
designated by notice in writing to the other party, provided that notice of any
change in address must actually have been received to be effective hereunder.

        5.3. Integration. This Agreement and the Exhibits hereto are the entire
agreement of the parties with respect to the subject matter hereof and
supersedes any prior agreement or understanding relating to Executive's
employment with or compensation by LXR. Any waiver, modification or amendment of
any provision of this Agreement shall be effective only if in writing and signed
by the parties hereto.

        5.4. Binding Effect. Subject to Section 5.1, this Agreement shall inure
to the benefit of and be binding upon the parties hereto and their successors,
assigns, heirs and personal representatives.

        5.5. Counterparts. This Agreement may be executed in two counterparts,
each of which shall be deemed an original and shall together constitute one and
the same instrument.

        5.6. Severability. If any provision hereof shall, for any reason, be
held to be invalid or unenforceable in any respect, such invalidity or
unenforceability shall not affect any other provision hereof, and this Agreement
shall be construed as if such invalid or unenforceable provision had not been
included herein. If any provision hereof shall for any reason be held by a court
to be excessively broad as to duration, geographical scope, activity or subject
matter, it shall be construed by limiting and reducing it to make it enforceable
to the extent compatible with applicable law as then in effect.

        5.7. Governing Law. This Agreement shall be governed by the laws of the
California state, without regard to its conflict of law provisions.

        5.8. Arbitration. Any controversy or claim arising out of, or relating
to, this Agreement or the breach of this Agreement will be settled by
arbitration by, and in accordance with the applicable National Rules for the
Resolution of Employment Disputes of the American Arbitration Association and
judgment upon the award rendered by the arbitrator(s) may be entered in any
court having jurisdiction. The arbitrator(s) will have the right to assess,
against a party or among the parties, as the arbitrator(s) deem reasonable, (a)
administrative fees of the American Arbitration Association, (b) compensation,
if any, to the arbitrator(s)



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and (c) attorneys' fees incurred by a party. Arbitration hearings will be held
in San Francisco, Contra Costa or Alameda County, California. The provisions of
California Code of Civil Procedure Section 1283.05 will apply to any
arbitration.

        5.9. Expiration of Agreement. Unless extended in writing by the parties
hereto or terminated earlier by a party hereto, this Agreement shall expire on
October 12, 2001. Executive may terminate this Agreement prior to such date upon
thirty (30) days notice to LXR. This Agreement may be terminated by LXR without
notice.

        5.10. Headings. The section headings used in this Agreement are intended
for convenience of reference and shall not by themselves determine the
construction or interpretation of any provision of this Agreement.

        IN WITNESS WHEREOF, the undersigned have duly executed and delivered
this Agreement as of the date first written above.


EXECUTIVE                                  LXR BIOTECHNOLOGY INC.



/s/ Samuil R. Umansky                      /s/ Paul J. Hastings
-----------------------------------        -------------------------------------
Samuil R. Umansky                          Paul J. Hastings
Vice President of Molecular                President and Chief Executive Officer
Pharmacology and Chief Scientific 
Officer



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