EXHIBIT 10.8 CERTAIN INFORMATION IN THIS EXHIBIT IS SUBJECT TO A REQUEST FOR CONFIDENTIAL TREATMENT. IN ACCORDANCE WITH RULE 406 UNDER THE SECURITIES ACT OF 1933, AS AMENDED, SUCH INFORMATION HAS BEEN OMITTED AND FILED SEPARATELY WITH THE SECURITIES...

                                                                    EXHIBIT 10.8

CERTAIN INFORMATION IN THIS EXHIBIT IS SUBJECT TO A REQUEST FOR CONFIDENTIAL
TREATMENT. IN ACCORDANCE WITH RULE 406 UNDER THE SECURITIES ACT OF 1933, AS
AMENDED, SUCH INFORMATION HAS BEEN OMITTED AND FILED SEPARATELY WITH THE
SECURITIES AND EXCHANGE COMMISSION. THE LOCATION OF SUCH OMITTED INFORMATION HAS
BEEN INDICATED WITH AN ASTERISK(*).

THIS AGREEMENT is made the ninth day of February 1990

BETWEEN

MEDICAL RESEARCH COUNCIL of 00 Xxxx Xxxxxxxx, Xxxxxx XxX 0XX (hereinafter called
"MRC" which expression includes its successors and assigns) of the one part and

TANOX BIOSYSTEMS INC. of 00000 Xxxxxx Xxxx, Xxxxx 000, Xxxxxxx, Xxxxx 00000,
X.X.X. (hereinafter called "the Licensee" which expression includes its
successors and permitted assigns) of the other part

WHEREAS

(A) MRC is the proprietor of certain Patent rights in respect of genetic
engineering of monocolonal antibodies comprising the replacement in whole or in
part of the complementarity determining regions of one antibody by those of
another.

(B) By an Agreement between the parties dated 26th June 1989 MRC granted certain
rights to the Licensee to make use 0f those rights ("the Licence Agreement").

(C) The parties wish to make certain adjustments to the Licence Agreement as
hereinafter appears.

NOW THIS AGREEMENT WITNESSETH

1.   INTERPRETATION

     Terms defined in the Licence Agreement shall have the same meaning herein
     save where the context otherwise requires.

2.   AMENDMENT TO LICENCE AGREEMENT

2.1  The definition in Clause 1 of "the Boss Patents" shall be amended as
     follows:-

     "The Boss Patents" - shall mean the following Patents and Patent
     applications in relation to multi-chain polypeptides or proteins and
     processes for their production and any Patent granted or to Be granted on
     such Patent applications:-

     (i) European Patent Application D120694

     (ii) UK Patent 2137631

     (iii) PCT Application 84/00094

     (iv) US Patent 0000000

     (v) Japanese Patent Application 501609/84.

2.2  Clause 3(1)(ii) shall be amended to read as follows:-

     "A non-exclusive sub-Licence under the Boss Patents to the extent required
     to enable the Licensee to use the reshaping process in accordance with (i)
     above to produce products from mammalian cells and for no other purpose."

2.3  The following antibodies shall be deleted from Schedule 2 "Antibodies
     Excluded from the Licence" and shall cease to be excluded from the Licence
     Agreement:-

                                       *

2.4  The Licence Agreement shall remain in full force and effect as amended
     hereby.

3.   GOVERNING LAW AND JURISDICTION

     This Agreement is to be read and construed in accordance with and governed
     by the laws of England and the parties

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     hereby submit to the jurisdiction of the English Courts in relation to any
     dispute arising out of this Agreement.

IN WITNESS whereof the parties hereto have caused this Agreement to be executed
in the manner legally binding upon them by causing authorised representatives to
sign this Agreement.


SIGNED by                                               }
for and on behalf of the                                }    SIGNATURE ILLEGIBLE
MEDICAL RESEARCH COUNCIL                                }

SIGNED BY Xxxxx X. Xxxxx, Pres                          }
for and on behalf of                                    } /s/Xxxxx X. Xxxxx
TANOX BIOSYSTEMS INC.                                   }

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