Cancer Drug Shows Promise

Genentech Inc. said Monday that its drug Herceptin prolonged the lives of breast cancer patients in two large clinical trials, setting the stage for a new way to treat the disease.

The drug, which is used to treat advanced breast cancer, also showed effectiveness in preventing recurrence of the disease in patients who had undergone surgery for early breast cancer.

“This is a major advance for many thousands of women with breast cancer,” Andrew von Eschenbach, director of the National Cancer Institute, said in a statement.

U.S. sales of Herceptin could double to $1 billion as a result of the trials, adding to Genentech’s stable of blockbuster medicines, said Geoffrey Porges, an analyst with Sanford C. Bernstein & Co.

“It is highly likely they could have $3-billion cancer products,” he said. “They are now set to become the dominant player in cancer treatment for at least the end of the decade.”

Genentech has enjoyed a string of successes recently. Its cancer drug Avastin, which is approved to treat colon cancer, has shown effectiveness in treating lung and breast cancers and is on track to have sales of $1 billion this year. Rituxan, another Genentech cancer drug, has annual sales of more than $1 billion.

Investors drove Genentech’s shares almost 11% higher in after-hours trading. The outcome of the clinical trials was announced after the markets closed.

Herceptin is an intravenous drug that targets genetic switches that spur the growth of breast tumors. The switches, known as HER-2, are present in 20% to 30% of women with breast cancer. Since 1998, Herceptin has been used to treat advanced breast cancer in patients whose tumors tested positive for HER-2.

The clinical trials announced Monday could expand the use of Herceptin to women with early-stage breast cancer whose tumors have HER-2.

The studies involved 5,500 women and were designed to see whether Herceptin could prevent the recurrence of cancer after surgery. The patients were divided into two groups: one received a combination of Herceptin and chemotherapy; the other received only chemotherapy.

The trials showed that women who received Herceptin had a 52% decrease in cancer recurrence compared with patients on chemotherapy alone. The National Cancer Institute, which sponsored the study in collaboration with Genentech, said the result was “highly statistically significant.”

The results, which were based on an interim examination of 3,300 patients, were so positive that the agency stopped enrolling patients in the study, which has been continuing since 1999.

The cancer institute did not reveal how much longer the patients lived. More details from the studies, including how long patients lived, will be presented at a medical meeting next month in Orlando, Fla.

“These are extraordinary results,” said Mark Pegram, director of the women’s cancer program at UCLA’s Jonsson Comprehensive Cancer Center. Early research on Herceptin was performed at UCLA, where the HER-2 switch was discovered.

“When we saw the improvements in advanced breast cancer, we thought Herceptin might work even better as a [post-surgical] therapy,” Pegram said. “That was our original hypothesis.”

Susan Desmond-Hellman, Genentech’s president for product development, said the statistical hurdles set for Herceptin in the trials were high.

“It had to be way better than chemotherapy alone,” she said.

Patients in the trial received Herceptin every three weeks for one year. At a cost of $3,195 monthly, Herceptin could add $38,340 to the cost of treatment for women with early-stage breast cancer. Desmond-Hellman said she didn’t think price would be an obstacle for insurers because the treatment prevented the recurrence of cancer.

“We are not talking about adding two months or five months” to patients lives, she said. “We are talking about having breast cancer stay away and never come back” for many women.

According to the American Cancer Society, an estimated 211,000 women will be diagnosed with breast cancer this year and 40,000 will die.

Genentech shares fell 41 cents to $69.43 on the New York Stock Exchange before climbing as high as $77 after hours.