Q & A with Dr. Patricia Steeg, Ph.D.

July 6, 2016 at 11:42 pm Leave a comment


Dr. Patricia Steeg

To reduce deaths from metastatic breast cancer, Dr. Steeg believes researchers need to conduct a new type of trial—one that would test drugs that laboratory studies have shown can prevent new metastases from developing. BCT spoke with Dr. Steeg about this new approach to clinical trials.

Q: Why do you think changing the way clinical trials are designed can reduce breast cancer deaths?

A: If we change the way trials are designed, we can enroll patients at different points, treat them with different types of targeted therapies, and use different end points that will still be relevant to patients’ quality and quantity of life.

I am advocating for metastasis prevention studies. The bulk of the preclinical data (studies done in cells and mice) says we can prevent metastases much better than we can shrink ones that have formed. So the question is: Is that true or is that just something we see in mice?

Q: How can you find out?

 A: That’s where the problem is. You can’t do an adjuvant trial that enrolls 1,000 people for each drug that might prevent metastases. (Adjuvant treatment is given after surgery to prevent recurrence.) So, I’m advocating we run smaller trials that enroll either super high-risk patients in the adjuvant setting or patients with limited metastases. The endpoint would be the development of a first or a new metastasis.

Q: Why do you think researchers are resistant to trying this?

A: It is something new. Every time I present this concept to oncology groups they say ‘Pat, of course you are right—but this is not the way we have done trials.

There is limited funding for clinical trials and they are going with what they know. So there is an element of habit, of risk-aversion. Also, I don’t think companies are going to fund these kinds of trials because they have yet to lead to a drug that has been approved by the Food & Drug Administration (FDA). It will take a few brave people with money to run these trials and say, ‘Yes, it works.’ Then more will jump in.

You can learn more about all of the breast cancer trials taking place at the NCI Center for Cancer Research here.

Q: How does what you are talking about differ from regular trials?

A: The trials with the high-risk patients would be mini-adjuvant trials to see if they reduce the risk of recurrence. For the patients with metastases, the trial would look at whether the drug prevents more metastases.

Q: Are there drugs that might stop new metastases from developing?

A: They are called Src inhibitors. They target an enzyme in the cancer cell that plays a role in cell movement and colonization—two things that happen in the metastatic process but don’t happen in a cell sitting still. There were two Src inhibitors that were studied in metastatic trials but those trials didn’t show the drug was effective. But what was measured was whether they shrunk existing tumors. Yet, the literature shows that they prevent new tumors—not shrink ones that are already there. And that’s what needs to be measured—whether they prevented new tumors from developing.

Q: If they could prevent new metastases, how might they be used?

A: The Src inhibitor could be given after standard treatment. I think it would be a maintenance regimen. A patient would have the standard of care and then take the inhibitor for a long time. We are seeing this in lung cancer, where studies are having patients take a low dose of a maintenance drug, and seeing some benefit.

Q: Are you going to do this type of trial?

A: At the NCI we are developing a trial to see if the oral chemotherapy drug temozolomide (which is used to treat some types of brain cancer) can prevent new brain metastases. We found in mice that a low dose of the drug will prevent brain metastases. So we are going to enroll patients with 1-5 brain metastases and treat them with stereotactic radiosurgery (radiation directed at the brain metastases) and then randomly assign half to also start on temozolomide. So, it’s following the standard of care and looking to see if we can prevent new metastases.

The trial Dr. Steeg is developing will take place at the NIH Clinical Center in Bethesda, Maryland. You can learn more about all of the breast cancer trials taking place at the NCI Center for Cancer Research here. Some of these trials cover participants travel expenses to and from the NCI.

You can read more about Dr. Steeg’s ideas about clinical trials in this article published in Nature in May 2012. You can listen to her discuss these ideas here

Entry filed under: Metastatic breast cancer, Metastatic breast cancer clinical trials. Tags: , , , , , .

Q & A with Dr. Gabriel Hortobagyi, MD Talking About Metastatic Breast Cancer Trials 

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

Trackback this post  |  Subscribe to the comments via RSS Feed

%d bloggers like this: