Neuro-oncologist Antonio Omuro specializes in treating patients with different types of brain tumors. He trained as a doctor in his native Brazil and worked in France before joining the Memorial Sloan-Kettering staff in 2008.
Dr. Omuro recently received a Cancer Clinical Investigator Team Leadership Award from the National Cancer Institute — an honor that recognizes exceptional clinical investigators for their contributions to the advancement of clinical research through collaborative team science. He is currently the principal investigator for 18 clinical trials at Memorial Sloan-Kettering, ranging from early-stage trials investigating novel agents to later-stage studies evaluating new ways to use more-established drugs and treatments.
In this interview, Dr. Omuro discusses the results of recent clinical trials and the rewards for caring for patients with brain tumors.
Let’s talk about some recent clinical trial results that you’re particularly excited about.
One idea we’re working on is optimizing the use of drugs and other treatments that we already have. A trial we recently finished looked at the daily use of temozolomide [Temodar®] for recurrent glioblastoma. The findings were very promising, and now we’re looking to see how it compares to other treatments for recurrent disease in glioblastoma patients.
The other trial that we just completed was testing bevacizumab [Avastin®] in combination with a more aggressive radiotherapy schedule. In this study, radiotherapy is given more aggressively in only six days instead of the standard 30 treatments patients usually receive. The trial has produced excellent results in patients with unmethylated MGMT, a biomarker that usually indicates a poor prognosis. So we’re moving forward with a national, randomized phase II trial to test that combination against the current standard of care.
What novel drugs are currently being investigated in clinical trials? Are you looking at any targeted therapies?
“We think it is important is to develop treatments that work across the board on more than one subtype of tumor.”
—Antonio Omuro, Neuro-oncologist
Yes, we are looking at several targeted agents and different mechanisms of action. One challenge with drugs that target a particular molecular subtype of brain tumor is that each molecular abnormality is very rare. It’s difficult to develop treatments when there is only one patient out of 500 who has a certain mutation.
Many patients are treated in the community and have no access to high-end molecular characterization of their tumors and are not even aware that there could be clinical trials tailored for them. We are participating in large collaborative efforts to make those trials feasible. But in the meantime, we think it is important is to develop treatments that work across the board on more than one subtype of tumor.
One very exciting trial is for a drug called RO4929097. The drug is a gamma-secretase inhibitor, and it targets a pathway called Notch, which is involved in cancer stem cells. There is a theory that within a tumor there are certain cells that behave like stem cells, and that those cells are more resistant to radiation and chemotherapy.
The idea of this drug is to transform the cancer stem cells into regular cancer cells to see whether they will respond better to radiation and chemotherapy. The trial is for all types of malignant glioma, including glioblastoma, and it’s ongoing right now.
We are also coordinating with investigators at The Rockefeller University on a vaccine involving a type of immune cell known as a dendritic cell. In this type of treatment, the patient’s own dendritic cells are collected and processed in the lab along with the patient’s tumor cells, so that the dendritic cells “learn” to recognize the tumor as something to be destroyed. The dendritic cells are then injected back into the patient’s blood to produce an immune response against the tumor. This process requires fresh tumor, so the operation has to occur in our center.
What is it like to work with patients who have brain tumors?
The brain is of course one of the most important and delicate organs in our body. Unlike tumors in other organs, slight growth in the size of a brain tumor can sometimes translate into devastating symptoms. That makes it challenging for patients and their families to deal with this type of disease.
At the same time, it is very rewarding to take care of these patients. Most patients take the news about their disease really well, and they are strong fighters. In my experience, I rarely have patients who choose not to pursue treatment. They’re very keen on the idea of participating in clinical trials and other types of research activities, even when they realize it’s more to help future patients than themselves. Their families are very supportive, and I develop very good relationships with them. I do witness how difficult it can be for them, particularly if they develop disabling symptoms, but that is a strong reminder that I need to work harder to develop better treatments for their disease.
Most patients with brain tumors require several different treatments. How do you coordinate that with other specialists in the Brain Tumor Center?
Neuro-oncologists work very closely with everyone on the brain tumor team. We refer patients for surgery and radiation when they need it, and we take care of their needs throughout those treatments. We have the weekly brain tumor board where everyone comes together to talk about individual patients and to reach consensus on their treatments. I am very lucky to be surrounded by fantastic colleagues, and we keep learning from each other’s experiences.
Last updated: July 6, 2012