<PAGE>

Exhibit 10.13

Yarra

                                   AGREEMENT
                                   ---------


BETWEEN THE UNDERSIGNED

"FOUNTAIN PHARMACEUTICALS, INC.", having its registered office at Largo, Florida
(33777), 7279 Bryan Dairy Road, represented by Mr. Chris Whitaker, in his
capacity of Vice President Operations, hereinafter referred to as FOUNTAIN
PHARMACEUTICALS for the First Part,

and

"YARRA", Societe Anonyme authorized capital of 500.000 Francs, having its
registered office at GRASSE (06130) France, 107, Route du Plan, represented by
Mr. Jeffrey KAUFMAN, in his capacity of President of Board of Directors,
hereinafter referred to as YARRA for the Second Part,

WITNESSETH:

Whereas FOUNTAIN PHARMACEUTICALS has developed from its own research,
pharmaceutical products that it manufactures from its own formulae and
commercializes worldwide.

Whereas FOUNTAIN PHARMACEUTICALS is willing to have its products distributed in
the territory specified and has therefore approached YARRA.

Therefore FOUNTAIN PHARMACEUTICALS is willing to use the services of YARRA to
search, present and negotiate one or several licensing agreement(s).

It was agreed as follows:

I - DEFINITIONS

PRODUCTS: the "PRODUCTS" are as described in the schedule hereto

MARKETING PARTNER: The "MARKETING PARTNER(S) presented by YARRA to exploit the
products within the territory.

                                       1
<PAGE>

II - AIM OF THE CONTRACT

      II-1    FOUNTAIN PHARMACEUTICALS, assigns to YARRA for a period of two
              years the rights to search for and present one or more potential
              MARKETING PARTNERS for the "PRODUCTS", for the following
              territories:

              - Europe, Middle-East, Australia

      II-2    During the time of its mandate as foreseen above, YARRA acts as an
              intermediary to put FOUNTAIN PHARMACEUTICALS in contact with one
              or more potential MARKETING PARTNERS;

              YARRA has, additionally, the task of negotiating with the
              MARKETING PARTNERS and to participate in the conclusion of the
              operation.

III - OBLIGATIONS OF THE PARTIES

      III-1   Obligations of YARRA

              a.   YARRA is obliged to search for one or more potential
                   MARKETING PARTNERS for the PRODUCTS. In order to do this,
                   YARRA will use all means available, human and material, its
                   specialist knowledge of the field of activity concerned, and
                   its contacts.

                   YARRA will inform FOUNTAIN PHARMACEUTICALS of the identity
                   and nature of the potential MARKETING PARTNERS and will
                   transmit to FOUNTAIN PHARMACEUTICALS all useful information
                   in the possession of YARRA.

              b.   YARRA shall assist FOUNTAIN PHARMACEUTICALS in negotiating
                   the terms and conditions between FOUNTAIN PHARMACEUTICALS and
                   the potential MARKETING PARTNERS.

      III-2   Obligations of FOUNTAIN PHARMACEUTICALS

              a.   FOUNTAIN PHARMACEUTICALS is required to pay to YARRA the
                   remuneration as agreed hereafter.

              b.   FOUNTAIN PHARMACEUTICALS is similarly required to communicate
                   to YARRA all the information that is indispensable for the
                   execution of the operation.

                                       2
<PAGE>

      III-3   YARRA will be released from its undertaking in case of force
              majeure, that is to say events making the execution of its
              obligations impossible, also in case of intervention of the
              Responsible Authorities causing either a disruption of the
              economics of the contract or the impossibility of its execution.

IV -  REMUNERATION

      IV-1    Method of Calculation

      In exchange for its undertakings and work, YARRA will receive remuneration
      that is determined as follows:

              a.   a fixed fee of TEN THOUSAND (10,000) US Dollars payable at
                   the conclusion of each agreement, written or not, between
                   FOUNTAIN PHARMACEUTICALS and each MARKETING PARTNER, at the
                   latest, at the date of the first commercial sales.

              b.   a commission calculated as a percentage of the net revenue
                   related to PRODUCT sales to MARKETING PARTNERS by FOUNTAIN
                   PHARMACEUTICALS.

                   The percentage will be defined as set forth below:

                   Year              Commission

                   Year 1            20%
                   Year 2            15%
                   Year 3            10%
                   Year 4            5%

                   Year 1 begins at the date of the first invoice related to
                   each PRODUCT sales sent to the MARKETING PARTNER by FOUNTAIN
                   PHARMACEUTICALS.

      IV-2    Payment

              The remuneration foreseen in b. is payable according to the sales
              statements which will be established by FOUNTAIN PHARMACEUTICALS
              and communicated to YARRA at the end of each legal quarter before
              the 10th day of each month.

              Payments will be made by the method to be indicated by YARRA.

              To permit the possible control of the commission's follow-up,
              YARRA is authorized to request the examination by an independent
              auditor at YARRA expenses, of the account relating to the sales of
              the PRODUCT by FOUNTAIN PHARMACEUTICALS to ensure that the
              conditions foreseen in the first indent of this article are
              properly applied.

                                       3
<PAGE>

V - TERMINATION OF THE CONTRACT

This contract will terminate at the end of the period of two years if the search
mandate has not led to the conclusion of a distribution agreement, or at the
expiration of the payment of the remuneration foreseen in clause IV-1 b.
whichever is the later.

It will also terminate in the cases as noted in III-3 above.

Notwithstanding the termination of the contract, the conclusion of a
DISTRIBUTION agreement, concluded by FOUNTAIN PHARMACEUTICALS or any
intermediate person, with a MARKETING PARTNER presented by YARRA, occurring
within two years after the date of termination of the contract, will allow YARRA
to receive the remuneration as foreseen in article III.

VI - APPLICABLE LAW

This Agreement is expressly bound by French law.

Any dispute that may arise between YARRA and FOUNTAIN PHARMACEUTICALS, will be
definitively settled by the "Arbitration Rules" of the Mediterranean Arbitration
Institute, which has its registered office at CERAM B.P. 120, SOPHIA ANTIPOLIS,
06561 VALBONNE CEDEX.

                                       4
<PAGE>

Signed in duplicate,


the

at

FOUNTAIN PHARMACEUTICALS, INC.                        YARRA S.A.


/s/ Christopher J. Whitaker     21/3/00               /s/ Jeffrey Kaufman
--------------------------------------------          --------------------------

                                       5
<PAGE>

SCHEDULE ONE

Definition of the PRODUCTS

The "PRODUCTS" are:  LyphaZome(R)-based products

                                       6