HER2 and Zometa

I emailed the study coordinator of the Austrian study to find out the answer to that question.  Unfortunately, I did not recieve a response back.  This may be because I emailed right when the results were made public, and they were probably inundated.  I have not followed up with them since.

I also emailed Novartis, the manufacturer of Zometa to find out further information about the study and results.  Novartis did respond.  They did not separate out Her2+ as a separate catagory, probably because the study was started over 8 years ago and this was before Herceptin was approved for adjuvant use (thus no need to test routinely for early stagers).

One interesting thing I did glean from the additional Novartis information, is that PR negative women had a very statistically significant improved outcomes with Zometa, despite that fact that only about 10% of the study population was PR-.  For a statistically significant result to be obtained from such a small subset of patients, the reduction in recurrence must have been dramatic.  Since Her2+ are much more likely to be PR- than Her2-, I think that PR- can be used to some degree as a kind of proxy for Her2+ patients. 

I may be over interpreting, but I truely believe that it works for Her2+ just as well or better than for Her2-. 

I haven't heard of a Wisconsin study.

In the Austrian study the women were given Zometa every 6 months for 3 years.

Hi jap,

As far as I know, the number with recurrences that were Her2+ is not known.  But even if it were, it would not tell you the effectiveness of zometa in Her 2 + cancer.

The reason is as follows:  Lets say 25 out of 100 zometa treated Her2+ patients have a recurrence, and only 10 out of 100 zometa treated Her2- have recurrence in a 5 year period.  (these numbers are made up for illustration purposes).  You cannot conclude that zometa is not as effective in Her2+ as it is for Her2- because you do not know the number that would have recurred without the zometa.  If 50 out of 100 would have recurred without zometa, but only 25 out of 100 recurred with zometa, zometa reduced recurrence by 50% (50-25)/50).  If only 10 out of 100 Her2- recurred with zometa, but only 12 out 100 would have recurred without zometa.  Zometa reduced recurrence in Her2- by 17% (10-12)/12) .  In this example zometa was much more effective for Her2+(50% reduction in risk) than for Her2- (17% reduction in risk) even though the rate of recurrence is higher for Her2+ overall. 

Its confusing, I know   

I do hope the they publish recurrence rates for Her2 and other subgroups to help with decision making in the future.  However, the Austrian study was started before Her2+ was routinely tested in early stage cancer, so the investigators would have to go back and test old tumor samples, if the have them. 

September -

zometa is a drug that is approved to treat bone metastasis.  But in a large, well conducted study, it was demonstrated that zometa given every 6 months for 3 years reduced the risk of breast cancer recurrence in non-metastatic patients by 36%.  There is also supportive data from 2 other trials that also show significantly reduced recurrence with zometa.

The drug has a very good side effect profile (generally a little achy for a day after infusion), and many women feel nothing at all.  There is a rare significant side effect called osteonecrosis of the jaw (ONJ) that can occur in women with metastatic cancer are treated every 3-4 weeks for long periods of time.  At the reduced frequency used to prevent metastasis, I am not aware of any cases of ONJ.  In the large Austrian study where zometa was shown to prevent recurrence, there were zero cases of ONJ out of 900 women who received active drug.

Many of us who are not low risk for recurrence have it on the same protocol as the original study, including those that were Her2+, node+, PR-, or larger tumor.  See stage III forum under the thread "zometa" for much more on this topic. 

Zometa is used to treat bone mets, but it is primarily an drug to treat osteoporosis.  It is a biphosphonate drug along with others such as Fosamax and Boniva.  Actonel is another one that is used to treat osteoporosis though I haven't confirmed yet that it is also a biphosphonate drug. I just googled Actonel and it is a biphosphonate.