Tarceva Lifts Lung Cancer Survival Rate by 42%

Generally speaking, Wall Street's biotech fund managers were hoping to see a minimum of a 40%, or two-month, improvement in survival.

An oral drug, Tarceva is a member of the closely watched class of drugs that attempts to halt the growth of cancer cells by blocking a key enzyme, epidermal growth factor, or EGF. In this way, Tarceva is very similar to AstraZeneca's(AZN) Iressa, the first of these EGF inhibitors to be approved in the U.S., also for late-stage non-small-cell lung cancer patients. ImClone's(IMCL) Erbitux is also an EGF inhibitor, but it's an injectable drug, so it works in a slightly different way.

Wall Street's sales estimates for Tarceva in non-small-cell lung cancer are wide ranging, from $500 million to well above $1 billion -- although such projections are mere guesses, since the drug is not yet approved.

The consensus view is that Tarceva will likely be viewed by many doctors as superior to AstraZeneca's Iressa. That's because the Tarceva study is the first controlled study of an oral EGF inhibitor drug to demonstrate that it can boost the survival of advanced non-small-cell lung cancer patients.

Iressa was approved on the basis of uncontrolled studies that showed the drug shrank tumors in about 10% of patients; the studies were not designed to look at changes in patient survival. Last year, AstraZeneca reported worldwide Iressa sales of $228 million.

Interestingly, in the Tarceva study, only 8.9% of patients responded (had their tumors shrink by 50% or more). That's a lower patient response rate than what AstraZeneca showed with Iressa in its studies -- a 10% patient response rate. AstraZeneca is currently conducting controlled studies to determine how well Iressa boosts survival in late-stage non-small-cell lung cancer patients. The fact that Iressa's response rate was higher than that for Tarceva may lead some to predict that Iressa might also produce a stronger survival benefit. A definitive answer will have to wait until the studies are complete.

OSI shares closed Friday at $78.53, up $1.53, or 2%; Genentech shares closed at $59.61, down 49 cents or 0.82%.

>To order reprints of this article, click here: Reprints