* Tarceva triples progression-free survival in sub-group
* Vies with AstraZeneca's Iressa as targeted treatment
* Roche's MetMab adds benefit to Tarceva in some patients
MILAN, Oct 9 (Reuters) - Two targeted lung cancer drugs from Roche (ROG.VX) showed impressive results in clinical trials on Saturday, highlighting how treating the disease is becoming much more focused.
A sub-set of lung cancer patients whose tumours carry a particular gene mutation lived nearly three times longer without their disease getting worse after taking Tarceva compared to those on standard chemotherapy, Chinese researchers reported.
The finding sets up a tussle between the Swiss drugmaker and AstraZeneca (AZN.L), whose product Iressa was approved in Europe last year for treating the same group of patients with a tumour 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 pills -- would depend on the perceived balance of their efficacy and side effects.
Roche has applied for a licence 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.
A final-stage Phase III trial of 165 Chinese patients with non-small lung cancer showed that 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 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 tumours 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 (4503.T) for $4 billion.
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 tumours 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. They also lived longer, although the increase in overall survival was not statistically significant.
Other companies working on MET as a cancer target include ArQule (ARQL.O), which presented early data on its experimental drug at a U.S. cancer meeting earlier this year. (Eediting by Ron Popeski)