Promising New Developments on the Breast Cancer Front
ImmunoGen and Roche
ImmunoGen's (IMGN) investigational breast cancer drug trastuzumab-DM1 (T-DM1) is shaping up to be a strong candidate as a third-line treatment for HER2-positive breast cancer. T-DM1 is a combination of Genentech's -- a unit of Roche (RHHBY) -- Herceptin (trastuzumab) and a cancer cell-killing agent from ImmunoGen. Results from a midstage trial showed that T-DM1 shrank tumors in 33% of critically ill breast cancer patients who no longer responded to treatment with Herceptin or GlaxoSmithKline's (GSK) Tykerb. HER2-positive breast cancer is a particularly aggressive form of the disease.
The companies will likely try to gain an accelerated approval process for the drug from the U.S. Food and Drug Administration. If approved as a third-line treatment, T-DM1 would be the first such treatment for breast cancer and the first approved drug for ImmunoGen, which is set to receive mid-single-digit royalties on T-DM1 sales by Roche.
Meanwhile, the FDA is allowing Roche to resume enrollment in a late-stage trial of Avastin for treating early-stage HER2-negative breast cancer. The agency had suspended the trial on Sept. 25. For now, it seems, the risk-benefit assessment remained unchanged. Genentech's Avastin, which works by starving tumors of blood supply, is also used to treat lung and colon cancer. It had annual global sales of $5.1 billion in 2008.
Sanofi, Onyx and Merck
The good news from French drugmaker Sanofi-Aventis SA (SNY) came Friday when it said U.S. regulators will review its BSI-201 experimental breast cancer drug on an accelerated basis. BSI-201 is being studied in women with "triple negative" metastatic breast cancer, meaning their tumors don't respond to typical hormonal therapies or drugs that target the HER-2 protein. So far, a phase II study found that women on the drug had a median survival of 12.2 months, compared with 7.7 months for the chemotherapy-only group.
Onyx Pharmaceuticals Inc. (ONXX) and Bayer AG are going head to head with Roche's Avastin. They said their Nexavar pill, approved for liver and kidney tumors, extended the lives of women with advanced breast cancer by delaying growth of malignancies that had spread or recurred. ONXX closed 3.5% higher on Friday, but it's giving most of it back today.
Merck & Co. (MRK), too, announced that its experimental compound MK-0752 was able to kill off cancer stem cells that linger in the breast after chemotherapy. These cells are suspected to be the cause of relapses after chemo and radiation treatments.
A Change in the Standard of Treatment?
New findings from the Breast Cancer International Research Group suggest that the risks associated with a class of chemotherapy drugs called anthracyclines, which are widely used to treat breast cancer, outweighed their benefits in some patients because they can also damage the heart. The findings renewed a debate over whether the chemotherapy drugs, which have been around since the 1960s, should remain the standard of care in treating breast cancer, or whether newer drugs should be used more frequently instead.
The researchers evaluated the efficacy and safety of two separate regimens to treat breast cancer, one with anthracyclines and another with non-anthracycline drugs, and compared the results to a control group. After five years, women receiving the combination with the anthracyclines had significantly more heart damage than those getting the non-anthracyclines. Of course, other experts say the data aren't convincing enough to change the standard of care.
Vaccines and "Natural Implants"
Generex Biotechnology Corp. (GNBT) announced interim results from a mid-stage study of a novel immunotherapeutic vaccine, that is, a vaccine to prevent the recurrence of the disease after being treated. The results showed that only half the number of patients who received the vaccine relapsed, compared to those not receiving the vaccine. GNBT shares jumped over 9% on Monday.
Finally, stem cell researchers reported that they found a technique that allows breast cancer patients to grow "natural implants" from their own cells. The study found the approach effective and could soon become standard treatment. That may not be the best news for breast-implant maker Allergan (AGN), but it sure is for patients.