New drug gives disappointing results in lung cancer

Wednesday, January 14th 2004, 12:00 am
By: News On 6

LONDON (AP) _ A drug that has prolonged the lives of many breast cancer patients has failed to live up to hopes that it might help people with lung cancer, new research has found.

In a study outlined this week in the European journal Annals of Oncology, those treated with Herceptin in combination with two chemotherapy medicines did no better than patients treated with the chemotherapy drugs alone.

However, the study, involving about 100 lung cancer patients, gave a hint that a very small fraction of patients with a particular genetic profile may benefit.

Herceptin, a standard treatment for spreading breast cancer, belongs to a new set of cancer drugs called targeted therapies, which are intended to arrest cancer by disrupting the internal signals that fuel its unruly growth.

Herceptin targets a gene called HER-2 and its protein. In breast cancer it typically delays progression by a few months in the quarter of victims with a particular genetic profile.

Scientists were hopeful that Herceptin might benefit lung cancer patients because in many the HER-2 gene is switched on. Also, test tube studies had shown the drug seemed to work better in a chemotherapy combination on lung cancer cells than it did on breast cancer cells.

``It was very disappointing therefore to find that the survival times and the time to the disease progressing were very similar _ between six and seven months for both,'' said the study's leader, Dr. Ulrich Gatzemeier, head of thoracic oncology at Grosshansdorf Hospital in Germany.

Dr. Len Lichtenfeld, deputy chief medical officer of the American Cancer Society, said the findings show that for the large majority of lung cancer patients, Herceptin is not going to be the answer.

``Positive or negative, this is important information,'' he said. ``We now know a lot more than we did before this trial was done. This type of information will provide significant guidance to others.''

``We are perhaps at the end of the beginning of using targeted therapies,'' said Lichtenfeld, who was not involved with the research. ``We're still learning about how these cells work. We are still finding the targets that we have to test. We're going to get there, it's just taking us a longer time.''

However, the study found that five of the six patients who had extremely high levels of the HER-2 protein responded to the drug better than the other patients did. It was nearly 8 1/2 months before their disease progressed compared with just over six months for the patients with lower HER-2 levels, Gatzemeier said.

But experts say the fraction of patients who could benefit is so small that limited resources may better be directed elsewhere.

Another targeted drug, Iressa, also has failed to show a benefit as a mainline lung cancer medicine.