Genentech Inc. and Tanox Inc have received a request for additional information and documentary materials, commonly referred to as a "second request," from the US. Federal Trade Commission (FTC) in connection with Genentech's proposed acquisition of Tanox. The second request extends the waiting period imposed by the Hart-Scott-Rodino antitrust improvements Act of 1976, the expiration of which is a condition to the completion of the acquisition.

Genentech and Tanox continue to engage in active and productive discussions with the FTC and intend to cooperate fully with the FTC in its review of the proposed acquisition. The companies anticipate that the FTC's review could extend beyond the first quarter of 2007. The companies expect that the transaction will close within the first half of 2007, subject to the satisfaction of other customary closing conditions.

At a special meeting on January 15, 2007, Tanox stockholders voted to approve the merger agreement providing for the merger of Tanox and a wholly owned subsidiary of Genentech.

Genentech is a leading biotechnology company that discovers, develops, manufactures, and commercialises bio therapeutics for significant unmet medical needs.

A considerable number of the currently approved biotechnology products originated from or are based on Genentech science.

Tanox is a biotechnology company specializing in the development of monoclonal antibodies. The company develops innovative bio therapeutics for the treatment of immune-mediated diseases, inflammation, infectious disease and cancer.

Tanox's lead investigational therapy, TNX-355, is a viral-entry inhibitor antibody to treat HIV/AIDS. TNX-355 has shown significant antiviral activity in phase 2 clinical testing. Tanox's first-approved drug, Xolair (omalizumab), is the first antibody approved to treat moderate-to-severe confirmed, allergic asthma.