Two experimental drugs developed by
biotechnology companies -- one to prevent heart attacks and the other
to help people quit smoking -- have shown promising preliminary
results, executives said.
One company, AtheroGenics, said
yesterday that its drug for atherosclerosis had significantly reduced
the volume of plaque that can clog arteries. The results, in a
midstage clinical trial, sent the company's stock soaring in
after-hours trading.
The other company, Nabi
Biopharmaceuticals, is expected to announce today that its vaccine
against nicotine helped people quit smoking in a small clinical trial.
The results of the AtheroGenics
trial had been eagerly awaited because removing fatty plaque from the
arteries is considered a new goal for cardiovascular drug therapy.
Even the statins, the widely used anticholesterol drugs, do little if
anything to reduce plaque.
AtheroGenics said its drug,
AGI-1067, reduced plaque volume about 3 percent to 4 percent after a
year, as measured with ultrasound. The reduction was statistically
significant compared with the patients' starting levels, but not
compared with the lesser reductions in patients who got a placebo.
Doctors in the trial cautioned that
the preliminary results covered only 133 of about 260 patients, but
nevertheless were promising.
''We want to see the final data but
at the same time, I'm encouraged,'' Dr. Steven E. Nissen, a
cardiologist at the Cleveland Clinic, said on a company-sponsored
conference call with analysts. ''It's a substantial change.''
Dr. Nissen said that while it could
be misleading to compare the results of different trials, the
reduction in plaque achieved by AGI-1067 was roughly equivalent to
that recorded in a 47-patient trial last year using a drug developed
by Esperion Therapeutics. In December, shortly after the results of
Esperion's trial were announced, Pfizer agreed to pay $1.3 billion to
acquire the company.
Speculation that AtheroGenics might
also be acquired -- or at least will sell the rights to AGI-1067 for a
large sum -- helped fuel the rise in the company's stock. The stock
closed down 43 cents at $23.16 in regular trading but soared as much
as 80 percent in after-hours trading.
AGI-1067, which fights the
inflammation involved in heart disease, is in some sense more
attractive than Esperion's drug because it is taken as a pill rather
than given by intravenous infusion. AtheroGenics, based in Alpharetta,
Ga., is already in a final-stage trial to determine if the drug
actually does prevent heart attacks. If so, it hopes to apply by the
end of next year for approval from the Food and Drug Administration.
As for Nabi's nicotine vaccine, 33
percent of those who got the highest dose quit smoking for at least 30
consecutive days compared to 9 percent who got a placebo, Dr. Henrik
S. Rasmussen, Nabi's senior vice president for clinical, medical and
regulatory affairs, said in an interview. Still, the trial was small,
with only 68 patients, and it could not be ruled out that the
difference between the vaccine and the placebo resulted from chance.
Two investigators in the trial, Dr.
Stephen I. Rennard of the University of Nebraska and Dr. Dorothy
Hatsukami of the University of Minnesota, called the results
encouraging.
Smokers find it hard to quit because
the nicotine binds to receptors in the brain and gives them a positive
feeling, Dr. Rasmussen said.
The vaccine, which was given by four
injections over six months in the trial, consists of nicotine
connected to a detoxified bacterial protein, which, when injected,
causes the body to form antibodies against nicotine. (Just injecting
nicotine by itself would not elicit the antibodies.) After that, if a
person smokes, the antibodies would bind to the nicotine and prevent
it from reaching the brain.
''We're basically taking away the
positive enforcement, which is the main reason people can't stop
smoking,'' Dr. Rasmussen said.
Nabi, based in Boca Raton, Fla.,
will do more studies to determine the best dose and hopes to begin
final-stage trials by the end of next year, Dr. Rasmussen said.
Xenova, a company based in Britain,
and Cytos, based in Switzerland, are also working on nicotine
vaccines, while Pfizer and Sanofi-Aventis are testing drugs that work
by other means. The therapies already approved to help people quit
smoking are GlaxoSmithKline's drug Zyban, and a variety of patches,
gums and other products that contain nicotine, Dr. Rennard said.
Published: 09 - 28 - 2004 , Late
Edition - Final , Section C , Column 3 , Page 3
