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                                                                   Exhibit 10.72

4 March 1999

Mr K Kasses
Genta Incorporated
99 Hayden Avenue
Lexington
MA 02421
USA

Dear Ken

THE GENTA - JAGO JOINT VENTURE

The parties have been discussing a means of resolving their involvement in Genta
Jago Technologies BV (the Joint Venture) and the several agreements in being
between them concerning its operation and activities.

Genta is evaluating the fiscal and other consequences of acquiring SkyePharma's
interest in the Joint Venture. Regardless of the outcome of such evaluation, the
parties hare agreed to operate the activities of the Joint Venture in accordance
with what follows notwithstanding anything contained in the several agreements
referred to above. For the avoidance of doubt, SkyePharma shall mean all members
of the SkyePharma Group of Companies, on whose behalf SkyePharma commits.
SkyePharma is referred to as "Skye" hereafter.

1.   The Parties  waive, release and hold each other harmless and each of
     their respective partners, affiliates, shareholders, directors, officers,
     agents, advisors, representatives, employees, counsel and controlling
     persons within the meaning of the Securities Act of 1933, as amended (the
     "Act"), from any and all losses, liabilities, claims, damages and expenses,
     whether known or unknown, contingent or matured (collectively, the
     "Claims") whatsoever in any way related to, arising out of or in connection
     with (i) any and all unpaid development costs accrued as of the date
     hereof, (ii) the certain notes executed by the Joint Venture in favour of
     Genta for the funding of development and operational costs, and (iii) any
     and all obligations and/or responsibilities under the agreements set forth
     in Schedule A, including, without limitation, specifically Genta shall be
     released in all respects from the funding obligations under any such
     agreements.

2.   Henceforth, and pending the outcome of Genta's evaluation (mentioned
     above) and/or such other agreement as may be made between the parties, Skye
     shall benefit from all rights and become responsible for all obligations
     under existing development and license agreements between the Joint Venture
     and independent third parties, including Apothecon (now terminated),
     Brightstone and Krypton. Skye shall be solely responsible for the further
     development, marketing, distribution, manufacturing and funding of the
     Joint Venture products listed in Schedule B of the Restated Geomatrix
     License Agreement ("JV Products"), now being Schedule B to this agreement.
     In order to enable these  provisions to work Skye is hereby given authority
     to commit the Joint Venture in


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     all particulars, with third parties and without need of any further
     assurance from Genta or the signature of any of its officers.

3.   In consideration of the foregoing, the Joint Venture shall have a vested
     interest in the qualified income share from the license revenues of Skye
     relating to JV Products (the "Qualified  Income Share"), including license
     fees, milestones, royalties and other payments made in respect of a license
     granted in respect of the JV Products ("License Income"), but excluding
     reasonable and documented reimbursements by independent third parties for
     development costs and expenses of Skye. The Qualified Income Share shall be
     as follows:

     (a)   For JV Products for which the Joint Venture  and/or Skye have
           initiated development prior to the date hereof (as set forth
           of Schedule B), that:

           (i)   have been, or are in the future, licensed to independent third
                 parties, the Qualified Income Share of the Joint Venture
                 shall be equal to one hundred  percent (100%) of the License
                 Income; and

           (ii)  have been, or are in the future, licensed to an affiliate
                 company within the Skye group, the Qualified Income Share of
                 the Joint Venture shall be based on the terms for payments
                 owed to the Joint Venture pursuant to the license agreement
                 for  Naproxen entered into on 25th October 1996 between the
                 Joint Venture and Krypton Ltd., a wholly owned subsidiary of
                 Skye.

     (b)   For JV Products for which no development has occurred prior to
           the date hereof (as set forth in  Schedule C), that are in the
           future licensed to independent third parties or affiliates of Skye:

           (i)   within eighteen (18) months, then the Qualified Income Share
                 of the Joint Venture shall be 100% of the License Income; and

           (ii)  thereafter, the Qualified Income Share of the Joint Venture
                 shall be sixty-six percent (66%) of the License Income; and

           (iii) 3.(a)(ii) above shall apply to the determination of licence
                 income for licences to affiliate companies within the Skye
                 Group.

     (c)   For JV Products for which no development has occurred prior to
           the date hereof (as set forth in Schedule C), Skye is entitled
           to deduct from License Income actually received from independent
           third parties for each such product worked on prior to the
           execution of the development/license agreement with such
           independent third party up to an aggregate amount of CHF 500,000 per
           product/license to cover unreimbursed development fees that are
           incurred for such products.

4.   Until the date that is nineteen (19) years from the date hereof, all
     Qualified License Income shall be paid by Skye immediately upon receipt
     into an escrow account in the
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     name of the JV Company,  jointly controlled (for payments out) by Genta and
     Skye or their nominees (the "Escrow Account"). Any amounts received in the
     Escrow Account shall be disbursed to the Parties and Vecap Venture Capital
     Partners AG ("Vecap") pursuant to the Distribution List attached hereto as
     Schedule  D. Upon full  recovery of all amounts set forth for the credit of
     each of the Parties and Vecap, Genta and Skye shall each receive fifty
     percent (50%) of all additional Qualified License Income.

5.   Subject to the further agreement between the parties the Joint Venture
     shall be maintained by an independent third party (appointed by agreement),
     on behalf of the parties, on a minimal basis, with only those functions
     performed by it or in relation to it, which are strictly  necessary  for
     purposes of this agreement, and/or to maintain the integrity of its
     Corporate being (audit and registration fees, etc). For avoidance of doubt
     such independent third party will invoice both Genta and Skye for 50% each
     of any necessary costs and expenses, reasonably incurred in the fulfillment
     of this paragraph 5.

Both parties acknowledge that this agreement represents an interim solution and
that it shall obtain until they are able to resolve the relationship between
them to their mutual satisfaction.

If the foregoing accurately reflects your understanding of what we have agreed,
will you please evidence accordingly by signing and returning one copy of this
agreement.

Yours sincerely


PETER WARBURTON
COMPANY SECRETARY & INTERNATIONAL COUNSEL


FOR:  GENTA INCORPORATED


BY: _________________________________       DATE: ____________________________
NAME:
TITLE: