By Ben Hirschler
MILAN (Reuters) - Roche's experimental drug MetMab and its established product Tarceva showed impressive results in lung cancer trials on Saturday, highlighting how treating the disease is becoming much more focused.
Cancer experts meeting Milan said personalized treatment, first seen in breast cancer, was now emerging as a major theme in lung cancer. The shift could reduce the use of less targeted drugs, including Roche's own top-selling Avastin.
Chinese researchers reported that a sub-set of lung cancer patients whose tumors carried a particular gene mutation lived nearly three times longer without their disease getting worse after taking Tarceva compared to those on standard chemotherapy.
The finding sets up a tussle between the Swiss drugmaker and AstraZeneca, whose product Iressa was approved in Europe last year for treating the same group of patients with a tumor mutation activating the epidermal growth factor receptor (EGFR).
Doctors attending the European Society for Medical Oncology (ESMO) congress in Milan said choosing between the two medicines -- both of which are convenient once-daily pills -- would depend on the perceived balance of their efficacy and side effects.
Roche has applied for a license in Europe to sell Tarceva as a first-line treatment for EGFR-positive patients, putting it on a par with Iressa.
Tarceva is already sold for second- and third-line treatment, regardless of genetic profile, and had sales last year of more than $1 billion.
The final-stage Phase III trial of Tarceva in 165 Chinese patients with non-small lung cancer showed those with the gene mutation lived a median of 13.1 months without their disease progressing, compared to 4.6 months for those on chemotherapy.
MORE THAN A YEAR
"More than one year progression-free survival is really very impressive," said Dr. Fortunato Ciardiello, professor of medical oncology at the Second University of Naples, who was not involved in the Roche-sponsored research.
Iressa, by comparison, gave patients an average 9.5 months before their tumors started growing back in earlier clinical tests. However, Ciardiello told Reuters the different trials were not directly comparable and added Iressa was generally viewed as having fewer toxic side effects than Tarceva.
Tarceva was developed by Roche with OSI Pharmaceuticals, acquired this year by Japan's Astellas Pharma for $4 billion.
Study leader Caicun Zhou of Shanghai Pulmonary Hospital, Tongji University, China, said the latest results suggested suitable patients should get Tarceva "as soon as possible."
As many as one in three Asian patients with lung cancer are estimated to have EGFR-positive disease, while the incidence in Western populations is just over 10 percent.
A separate and smaller mid-stage Phase II trial found that adding Roche's experimental antibody drug MetMab to Tarceva also markedly reduced the risk of disease progression in a different genetic sub-group.
MetMab, which is given intravenously, is an important new product for Roche, the world's biggest maker of cancer medicines, as it seeks to boost its position in the lung cancer field.
The U.S. study of 128 patients found that patients whose tumors expressed a cancer-associated molecule called MET reduced the risk of their disease progressing by 44 percent when given Tarceva and MetMab compared to those on Tarceva plus placebo. The median progression-free survival was improved from 6.4 weeks to 12.4 weeks.
These patients also lived longer, although the increase in overall survival was not statistically significant.
However, patients whose tumors did not express MET did worse on MetMab and Tarceva, possibly because MetMab interfered with Tarceva's activity in this group.
Other companies working on MET as a cancer target include ArQule, which presented early data on its experimental drug at a U.S. cancer meeting earlier this year.
(Editing by Toby Chopra)