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                                                                   EXHIBIT 10.24

February 26, 2000

eMedsecurities, Inc.
800 James Avenue
Scranton, PA 18510

Gentlemen:

In connections with our letter of understanding dated the date hereof (the
"Understanding") we hereby agree to indemnify and hold harmless you and your
affiliates, the respective directors, officers, stockholders, agents and
employees of you and your affiliates and each other person controlling you or
any of your affiliates (collectively referred to as "you" and "your"), to the
full extent lawful, from and against all losses, claims, damages, liabilities
and expenses (collectively, "Losses") incurred by you (including fees and
disbursements of counsel) which ( i ) results from or arise out of actions taken
or omitted to be taken (including any untrue statements made or any statements
omitted to be made) by us or by you with our consent or in conformity with our
actions or omissions or (ii) are otherwise result from or arise out of  your
activities on our behalf in connection with our Understanding, and we will
reimburse you for all reasonable expenses (including fees and disbursements of
counsel) as they are incurred by you in connection with investigating, preparing
or defending any such action or claim, whether or not in connection with pending
or threatened litigation in which you are a party. We will not be responsible,
however, for any Losses pursuant the preceding sentence which are finally
judicially determined to have resulted primarily from your willful misfeasance,
gross negligence or breach of provision 4 in the Understanding. We also agree
that you shall not have any liability to us for or in connection with such
Understanding except for Losses incurred by us which are finally judicially
determined to have resulted primarily from your willful misfeasance or gross
negligence or breach of Provision 4 in the Understanding. We further agree that
we will not, without the prior written consent of eMedsecurities ("EMED") settle
or compromise or consent to the entry of any judgment in any pending or
threatened claim, action, suit or proceeding in respect of which indemnification
may be sought hereunder (whether or not you are an actual or potential party to
such claim, action, suit or proceeding) unless such settlement, compromise or
consent includes an unconditional release of you from all liability arising out
of such claim, action, suit or proceeding. Payments pursuant to this paragraph
shall be paid by us promptly upon receipt of statement(s) from EMED setting
forth the amounts with respect to which indemnification and/or reimbursement is
sought pursuant to this paragraph.

We agree if any indemnification sought by you pursuant to this letter agreement
is unavailable or insufficient to hold you harmless, then (whether or not EMED
is the indemnified person), we and EMED will contribute to the Losses for which
such indemnification is unavailable or insufficient in such proportion as is
appropriate to reflect the relative benefits to us, on the one hand, and EMED on
the other hand, in connection with our Understanding referred to above, subject
to the limitation that in any event EMED's aggregate contribution to all Losses
with respect to which contribution is available hereunder will not exceed the
amount of fees actually received by EMED from us pursuant to our Understanding
referred to above. Our indemnity, reimbursement
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and contribution obligations under this letter agreement shall be in addition to
any rights that you may have at common law or otherwise. We hereby consent to
personal jurisdiction and service and venue in any court in which any claim
which is subject to this letter agreement is brought against you. This letter
agreement shall be governed by and construed in accordance with the laws of the
State of New York without regard to principles of conflicts of laws. Any right
to trial by jury with respect to any claim or proceeding related to or arising
out of our Understanding or this agreement is waived. It is understood that, in
connection with our Understanding, EMED may also be engaged to act in one or
more additional capacities, and that the terms of the original Understanding or
any such additional Understanding(s) may be embodied in one or more separate
written agreements. The provisions of this letter agreement shall apply to the
original Understanding, any such additional Understanding(s) and any
modification of the original Understanding or such additional Understanding(s)
and shall remain in full force and effect following the completion or
termination of the Understanding.

Very truly yours,


CENTAUR PHARMACEUTICALS, INC.

By:   /s/ Lucy Day
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Lucy Day
Chief Financial Officer

Accepted:

EMEDSECURITIES, INC.

By:   /s/ Robert W. Naismith, Ph.D.
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Robert W. Naismith, Ph.D.
Chairman and CEO