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CONFIDENTIAL TREATMENT REQUESTED EXHIBIT 10.77

CONFIDENTIAL TREATMENT REQUESTED UNDER RULE 24(b)(2) OF THE SECURITIES

AND EXCHANGE ACT OF 1934. CONFIDENTIAL TREATMENT REQUESTED IS REQUESTED

AND IS NOTED WITH "[CONFIDENTIAL TREATMENT REQUESTED]." AN UNREDACTED

VERSION OF THIS DOCUMENT HAS BEEN PREVIOUSLY FILED WITH THE SECURITIES

AND EXCHANGE COMMISSION.

EXCLUSIVITY AGREEMENT

THIS AGREEMENT is made the day of 22nd of December 2004

BETWEEN:

(1) PFC Therapeutics, LLC, a limited liability company organized under the

laws of Delaware, USA and having its principal place of business at

4660 La Jolla Village Drive, Suite 825, San Diego, CA 92122 USA

(hereinafter referred to as "PFC"), and

(2) LEO Pharma A/S, a company organized under the laws of Denmark and

having its principal place of business at Industriparken 55, DK-2750

Ballerup, Denmark (hereinafter referred to as "LEO")

RECITALS:

(A) The parties have provisionally agreed, subject to due diligence,

contract and the other terms and conditions specified herein, to a

transaction in which PFC will exclusively license to LEO certain rights

to PFC's product Oxygent(R).

(B) This Agreement sets out the framework of the exclusive negotiations

between PFC and LEO in connection with the transaction.

NOW, THEREFORE, THE PARTIES HEREBY AGREE AS FOLLOWS:

1. Definitions and Interpretation

1.1. In this Agreement, the following terms shall have the following

meanings unless the context requires otherwise:

"AFFILIATE" means any corporation, firm, partnership, organization or

entity that directly or indirectly controls, is controlled by or is

under common control with such entity. For the purpose of this

definition the term "control" means direct or indirect ownership of at

least fifty one percent (51%) of the outstanding equity voting stock

(or such lesser percentage which is the maximum allowed to be owned by

a foreign corporation in a particular jurisdiction) of an entity.

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*** CONFIDENTIAL TREATMENT REQUESTED ***

"AGENCY" means any governmental authority in the Territory responsible

for granting approvals and clearance for marketing and sale of the

Product.

"AGREEMENT" means this Exclusivity Agreement between PFC and LEO.

"BRIEFING PACKAGE" means the compilation of Data in relation to the

Product and the rational for the continued development and obtaining of

Marketing Authorizations for the Product in the European Union. The

Briefing Package is to be filed to EMEA with the purpose of obtaining a

scientific advice. The Briefing Package must be prepared and filed in

relation to relevant rules and regulations as set out by EMEA for such

procedures.

"CONTROL" or "CONTROLLED" means the possession of/or the ability to

grant a license or sublicense of Data or other intangible rights as

provided for herein without violating the terms of any agreement or

other arrangement with any third party.

"DATA" means information in the possession or Control of either Party

relating to the Product including, without limitation, confidential

know how, technical information, technology and trade secrets relating

to the Product, information relating to the pre-clinical and clinical

testing of the Product, information relating to any Clinical Trials,

information relating to any suspected adverse drug experiences with the

Product and any toxicological, pharmacological or pharmacokinetic

trials relating to the Product.

"EMEA" means the European Medicines Evaluation Agency.

"EXCLUSIVITY FEE" means the fee paid by LEO to PFC in exchange of the

exclusivity period and the rights granted in Clause 2.

"CGMP" means current Good Manufacturing Practice.

"IMPROVEMENTS" means all improvements, modifications or adaptations to

any part of the Data or the Product made or acquired by either Party

during the term of this Agreement.

"KNOW-HOW" includes without limitations all trade mark rights, and all

financial, scientific, technical, regulatory, marketing and commercial

know-how and Data concerning the Product.

"MARKETING AUTHORIZATIONS" means any approvals, product and/or

establishment licenses, marketing authorizations or registrations of

any federal, state or local Agency necessary for the commercial

manufacture, use, storage, import, export, transport, marketing or sale

of the Product in any country or regulatory jurisdiction of the

Territory.

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*** CONFIDENTIAL TREATMENT REQUESTED ***

"NET SALES" means the adjusted gross invoice price, the adjusted gross

invoice price being the aggregate sales of LEO and its Affiliates of

the Product to unaffiliated third parties in the Territory (but not

including sales between LEO and its Affiliates) less sales returns and

allowances, including trade, quantity and cash discounts and any other

adjustments, including those granted on account of price adjustments,

billing errors, rejected goods, damaged goods, recalls, returns,

rebates, chargeback rebates, fees, reimbursements or similar payments

granted or given to wholesalers or other distributors (including

retailers), buying groups, health care insurance carriers or other

institutions, freight and insurance charges billed to the customers,

customs or excise duties, sales tax and other taxes (except income

taxes) or duties relating to sales, and any payment in respect of sales

to any governmental or regulatory authority in respect of any federal

or state Medicaid, Medicare or similar program, all as determined in

accordance with generally accepted accounting principles on a basis

consistent with Company LEO's audited financial statements.

"NEW PRESENTATION" means any pharmaceutical product incorporating

perflubron and/or perflubrodec. whether alone or in combination with

other active or inactive ingredients, and any salts or derivatives of

such Product. "Product" shall include Combination Products.

"PARTIES" means PFC and LEO and "Party" means either of them as the

context indicates.

"PATENTS" means patents covering inventions that may be developed by

either Party during the term of the License Agreement and that relate

spec