UPDATE 1-Astra drug keeps lung cancer from worsening-study

* Progression-free survival 17.3 weeks versus 14 weeks

* FDA filing expected by June 30

* No progress with biomarkers

(Adds comments, details)

By Deena Beasley

ORLANDO, Fla., May 30 (Reuters) - AstraZeneca PLC's (AZN.L: Quote, Profile, Research)
Zactima, which failed two earlier trials, was shown in a
pivotal study to extend the amount of time patients survived
without their lung cancer worsening, researchers said on
Saturday.

Anglo-Swedish AstraZeneca plans to file for U.S. regulatory
approval of the oral drug, also known as vandetanib, by the end
of June.

The trial, called Zodiac, involved 1,391 patients with
advanced non-small cell lung cancer whose disease has worsened
after chemotherapy. It also found that almost twice as many
patients treated with a combination of Zactima and chemotherapy
drug docetaxel had shrinkage of their tumors, compared with
those given just chemotherapy.

Median "progression-free" survival for the group on the
combination therapy was 17.3 weeks, compared with 14 weeks for
the chemotherapy-alone patients, according to the study, which
was presented here at the annual meeting of the American
Society of Clinical Oncology.

The results also showed "a trend toward advantage in
overall survival," in patients who were "quite sick, quite
symptomatic," said Peter Langmuir, medical science director at
AstraZeneca.

DOUBLE MECHANISM OF ACTION

Like Roche Holding AG's (ROG.VX: Quote, Profile, Research) Avastin, Zactima is
designed to block the vascular endothelial growth factor, which
tumors need to develop a blood supply. The Astra drug also
targets the vascular epidermal growth factor receptor, the same
protein blocked by drugs like Tarceva, a product of Roche and
OSI Pharmaceuticals Inc (OSIP.O: Quote, Profile, Research).

A separate trial presented at ASCO showed that a
combination of Tarceva and Avastin reduced by 29 percent the
risk of disease progression compared to Avastin plus a
placebo.

The study was designed to test Tarceva as a so-called
maintenance therapy to help delay progression of the disease
following successful chemotherapy treatments.

"Here you have it all in one pill," said Dr. Roy Herbst,
chief of thoracic medical oncology at the University of Texas
M.D. Anderson Cancer Center and the author of the Zactima
study. "To my knowledge, this is the first instance in
second-line therapy where another therapy added to docetaxel
showed a benefit."

Analysts have estimated eventual sales of the drug at
around $500 million.

Although Zactima did not dramatically increase
progression-free survival in the trial, the fact that the drug
improved symptoms is very important, Dr. Herbst said.

"Clearly patients are progressing less quickly, but
unfortunately they are all going to succumb to their disease,"
he said. "We were able to show that with the increased time for
patients' tumors to grow, they were reporting that they were
feeling better."

AstraZeneca said efforts to determine which patient groups
were most likely to respond to its drug have so far had little
success.

Langmuir said Zactima adds rash and diarrhea to the list of
side effects seen from chemotherapy, but patients have less
nausea, vomiting and anemia.

Results from a fourth trial studying Zactima as a stand-alone
treatment after the use of Tarceva and other drugs are expected
later this year.

A previous trial, also presented at ASCO, showed that the
Astra drug works at least as well at Tarceva.

Lung cancer kills 1.2 million people a year and is the top
cause of cancer death globally. Many drugs are used to treat it,
but they almost always stop working eventually.

Langmuir said Astra is currently exploring a number of
development options for Zactima as a first-line lung cancer
therapy and in maintenance settings.
(Reporting by Deena Beasley, editing by Matthew Lewis)