Failed Avastin study detailed, other trials go on

* 77.4 pct of Avastin patients disease free vs 75.5 pct

* Results of second adjuvant trial expected next year

ORLANDO, Fla., May 30 (Reuters) - A failed study of
blockbuster drug Avastin in colon cancer patients who have
undergone surgery was detailed for the first time on Saturday,
but similar clinical trials are still ongoing.

The 2,710-patient trial, for which top-line results were
announced in April, found that adding Avastin to standard
chemotherapy did not improve disease-free survival for patients
with locally advanced colon cancer.

After a median follow-up of three years, the investigators
found that 77.4 percent of patients in the Avastin group were
alive and free of disease, compared with 75.5 percent of
patients in the control group, a difference that was not
statistically significant.

The results were presented here at the annual meeting of
the American Society of Clinical Oncology.

Avastin, known chemically as bevacizumab, is an antibody
designed to fight cancer by interfering with the blood supply
to tumors. It is made by Genentech, which is now a unit of
Switzerland's Roche Holding AG (ROG.VX: Quote, Profile, Research).

The drug, which has annual sales of about $4.4 billion, is
currently approved for treating metastatic colorectal, breast,
lung and later-stage brain cancers.

This was the first trial which sought to show Avastin's
ability to prevent cancer recurrence by wiping out microscopic
cancer cells that may remain in the body after tumors have been
removed by surgery, known as use in the "adjuvant" setting. But
several similar trials are under way, including a second in
early-stage colon cancer patients for which results are
expected next year.

"One interesting effect was that during the year that
patients were receiving bevacizumab we saw a benefit in
disease-free survival that subsequently diminished when
follow-up was completed," Dr. Norman Wolmark, chairman of the
Department of Human Oncology at Allegheny General Hospital and
the study's lead author, said in a statement.

He said the transient benefit illustrates that there is
more to learn about how Avastin works, and more clinical trials
are needed to determine how it can be used most effectively.

The trial was conducted by the National Surgical Adjuvant
Breast and Bowel Project group, chaired by Dr. Wolmark, and was
funded by the National Cancer Institute.
(Reporting by Deena Beasley, editing by Matthew Lewis)