San Antonio 2010 Take Aways: Drug News
Every December, people interested in breast cancer travel from around the world to San Antonio, Texas, to learn about the latest research in breast cancer.¬† What makes this meeting special is that researchers, oncologists, surgeons, radiation oncologists, patient advocates, and others involved in breast cancer attend.¬† When people with different roles in the fight against breast cancer get together, a patient advocate's experience can spark a new idea for a researcher.¬† A radiation oncologist's observation can illuminate a problem that a surgeon has noted.
Almost 8,000 people attended the 33rd Annual San Antonio Breast Cancer Symposium to learn from 2,000 presentations in December 2010. ¬†I have been reading about the presentations and have chosen some information to share with HealthCentral readers in this post and more to follow.¬† Many of this year's presentation were reports of studies on specific drugs.¬†
Zometa Study.¬† A new trial led by Robert Coleman, MD at the University of Sheffield in England finds that Zometa (zoledronic acid) prevented recurrence only in postmenopausal women, not premenopausal women as an earlier Austrian study reported.¬† However, if you have bone loss issues or cancer that has metastasized to the bone, then Zometa may still be appropriate for you.¬†
These two studies with different results show how complicated it can be for non-medical people to understand research data.¬† The headlines from this study report that the drug's maker Novartis has withdrawn its application for approval of the drug.¬† The fine print reveals that they have withdrawn the application only for the use of Zometa to prevent recurrence in premenopausal women with early-stage, hormone receptor-positive breast cancer.¬†
This fine print shows why it is crucial for you to discuss with your doctors their reasons for suggesting a particular drug and what the research data shows about its efficacy for patients like you.¬† For this drug, four different factors might affect whether you should take Zometa:¬† your current bone density, your menopausal status, your tumor's hormone receptor status, and the stage of your cancer.
Herceptin vs. Tykerb Study.¬† In this study led by Michael Untch, MD, of the Helios Clinic in Berlin, lapatinib (Tykerb) did not do as well as trastuzumab (Herceptin) patients with Her2-positive breast cancer. Tykerb worked for about 30% of the tumors, but it had more side effects than Herceptin which worked for 45% of the patients.¬† Does that mean that Tykerb is not for you?¬† Again there are complicated factors that your doctor will want to consider, but for most Her2 positive patients Herceptin will be the drug of choice.
Avastin Study¬† One of the major disappointments of the drug studies centers on Avastin (bevacizumab), which did not show statistically significant effectiveness in the first large randomized study for patients with non-metastatic breast cancer.¬† Researchers had hoped that Avastin would be a successful targeted therapy for patients with Her2 negative tumors.¬† The final word is not yet in on Avastin.¬† Research will continue, and it may yet turn out that it works well on a sub-group of breast cancer patients, but for now its use is in question.
Good News.¬† Sometimes knowing what doesn't work is a big medical advance.¬† But the average patient wants some good news about effective treatments.
PARP Inhibitor trial.¬† For several years we've been hearing about a new class of drugs that may change treatment for triple negative breast cancer the way Herceptin changed treatment for Her2 positive women.¬† These drugs are called PARP inhibitors and they work by preventing cancer cells from repairing their DNA after chemotherapy.¬† An early-phase trial led by Stacy Mouder of MD Anderson Cancer Center in Houston gave 34 patients with metastatic breast cancer a chemotherapy drug called irinotecan (Camptosar) and the PARP inhibitor iniparib.¬† About a third of the patients shows either partial or complete response to this drug combination, and 45% of the patients showed some clinical benefit.
Of course, this is a small study, so only time and more studies will tell if these drugs will work in larger patient populations.¬† For now the point is that scientists have a new way to kill cancer cells even in triple negative tumors.¬† These drugs are not yet ready for your neighborhood doctor to prescribe, but it is worth asking your doctor if participating in a PARP inhibitor trial is a viable option for you.
Chemo During Pregnancy.¬† Isn't there any good news from San Antonio that can help us today, you ask.¬† How about the finding on chemo during pregnancy?
There is nothing more heart-breaking to me than hearing about a woman who is diagnosed with cancer while pregnant.¬† Suddenly a woman who has been avoiding Tylenol and coffee finds out that she needs toxic chemotherapy drugs to save her life.¬† Naturally she is terrified to take chemo, but waiting until she delivers runs the risk of leaving her baby motherless. Sibylle Loibl, MD, of the German Breast Group in Neu-Isenburg, Germany, and her colleagues have found that making a choice between the baby's health and the mother's life is not necessary.¬† Their study of 260 women found that there was not an increased risk to the baby from the mother's chemo treatments.
The type of chemo is important.¬† Chemo drugs in the anthracycline family like Adriamycin are preferable to those in the taxane family because of the way they kill cancer cells.¬† Also the last chemo treatment should be given no later than week 32 or 33 because of the danger to the mother during delivery if ¬†chemo lowers her immune system ¬†near her delivery date.¬† So there are still details that have to be taken into consideration for pregnant cancer patients, but pregnant women with breast cancer can be treated without endangering the baby or mother.
In the next few weeks, watch for other news from San Antonio that I'll write about in my shareposts.