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SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, D.C. 20549
FORM 8-K
Current Report Pursuant to Section 13 or 15(d) of
The Securities Exchange Act of 1934
Date of Report (date of earliest event reported): September 13, 2000
TANOX, INC.
(Exact name of registrant as specified in its charter)
Delaware 000-30231 76-0196733
(State or other jurisdiction (Commission File No.) (I.R.S. Employer
of incorporation) Identification No.)
10301 Stella Link, Suite 110, Houston, Texas 77025-5497
(Address of principal executive offices) (Zip code)
Registrant's telephone number, including area code: 713-664-2288
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ITEM 5. OTHER EVENTS.
Tanox has received questions from investors and analysts regarding information
recently communicated by Genentech, Inc. and Novartis Pharmaceuticals
Corporation to clinical investigators in connection with certain ongoing
clinical studies of Omalizumab ("E25") and rhuMAb-E26 ("E26").
Tanox has been advised by Genentech and Novartis that E25 trials have been
placed on clinical hold or partial clinical hold due to observations in certain
ongoing safety studies in monkeys. The trial subject to partial clinical hold
will continue, but will not be enrolling new patients. The E25 holds will not
affect patients currently enrolled in long-term studies. E26 trials, currently
being conducted only in Europe, will also be placed on clinical hold.
While testing E25 and E26 in nonclinical toxicology studies, researchers
observed cases of abnormally lowered platelet counts, or thrombocytopenia, in
cynomolgus monkeys that received doses ranging from approximately 3 to 27 times
higher than the maximum clinical dose. In an E26 study, a ten-monkey group was
dosed with 15 times the maximum 270-mg dose safely administered recently in a
single-dose clinical study, resulting in two monkey fatalities.
E25 has been evaluated in Phase III clinical trials for the treatment of asthma
and seasonal allergic rhinitis in more than 1,950 patients, aged approximately 6
to 75 years, treated in 16 clinical trials over a six-year period. Genentech and
Novartis have advised that, given to humans at its therapeutic dose, E25 has not
been associated with a sustained decrease in platelets or any related bleeding
abnormalities, and any adverse events noted were similar in patients receiving
E25 or placebo. A low platelet count was measured on a single occasion in five
patients, and they believe this pattern did not suggest a treatment effect of
E25.
Genentech and Novartis are working with the FDA to modify safety data collection
protocols and will continue to work with the FDA and other regulators and
closely monitor data in ongoing and future clinical studies. Genentech has
advised Tanox that neither the clinical holds nor the animal findings are
expected to negatively affect the review of regulatory filings for E25.
Tanox is conducting a Phase I/II trial for Hu-901, an anti-IgE monoclonal
antibody different from E25 and E26, in patients severely allergic to peanuts.
Tanox will continue this study, but plans to inform its clinical investigators
of the information regarding the E25 and E26 safety studies.
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SIGNATURES
Pursuant to the requirements of the Securities Exchange Act of 1934, the
registrant has duly caused this report to be signed on its behalf by the
undersigned hereunto duly authorized.
Date: September 13, 2000 TANOX, INC.
By: /s/ John C. Morris
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John C. Morris
Senior Vice President of Operations
