WITNESSETH:

EXHIBIT 10.4                        AGREEMENT

This AGREEMENT made this 15th day of November, 1995 between Yale University
(YALE), a non-profit corporation organized and existing under and by virtue of a
special charter granted by the General Assembly of the Colony and State of
Connecticut and Oncorx Corporation, a Delaware Corporation having its principal
offices in New Haven, Connecticut ("LICENSEE").

                                   WITNESSETH:

WHEREAS, YALE and LICENSEE are parties to a License Agreement, dated August 31,
1994, under which YALE has exclusively licensed to LICENSEE a series of YALE
owned inventions relating to potential anti-tumor and anti-viral compounds.

WHEREAS, YALE and LICENSEE wish to amend the above mentioned agreement as
provided herein;

NOW, THEREFORE, in consideration of the premises and of the mutual covenants
contained herein and for other good and valuable consideration, receipt of which
is hereby acknowledged, YALE and LICENSEE hereby agree as follows:

1. Exhibit B shall be amended to include US Patent number 5,281,715, Xxxx X.
Xxxxxxxxxx and Tai-Xxxx Xxx, and all US and foreign cases which derive from this
case, and US patent application 08/142,858 Xxxx X. Xxxxxxxxxx and Tai-Xxxx Xxx,
and all US and foreign cases which derive from this case.

2. Article IV PAYMENTS AND ROYALTIES shall be amended to include the following
item:

4.5 Regarding any of the materials disclosed in US Patent number 5,281,715 Xxxx
X. Xxxxxxxxxx and Tai-Xxxx Xxx, or in any US and foreign cases which derive from
this case, LICENSEE shall pay to YALE milestone payments according to the
following schedule:

      One hundred thousand dollars ($100,000) upon completion of Phase II
      clinical trials;

      Two hundred thousand dollars ($200,000) upon NDA filing or foreign
      registration filing;

      Three hundred thousand ($300,000) upon NDA or foreign approval.

      Such payments shall be separate and not credited against any EARNED
      ROYALTIES.


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In all other respects the License will remain unchanged and in full force and
effect.

In witness whereof the parties have executed this Agreement as of the date first
above written.

YALE UNIVERSITY                                       ONCORX

By: /s/ Xxxxx Xxxxxxxx                                By: /s/ Xxxx Xxxxxx
    -----------------------                               ----------------------
Xxxxx Xxxxxxxx                                        Xxxx Xxxxxx, President
Associate Vice President for Finance


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