UW cancer researcher tells us, ‘it’s been a ride.’ She’s hopeful about cancer vaccine prospects

Over many decades of medical breakthroughs, every now and then we hear hopeful news of possible cancer cures. But for many people, especially those who lost loved ones, the hope has been frustrated. Now, there's another positive development to report on. It concerns cancer vaccines.

Dr. Nora Disis is a University of Washington professor of Medicine and Oncology, and the director of the UW Medicine Cancer Vaccine Institute. She told KUOW’s Kim Malcolm about her work.

This interview has been edited for clarity.

Kim Malcolm: You had a mention this week in a New York Times article. It had a rather provocative headline, "After Giving Up on Cancer Vaccines, Doctors Start to Find Hope." Is that an accurate overview? Did you and other doctors you know give up on cancer vaccines?

Dr. Nora Disis: I think that was a very provocative title. I at least have not given up on cancer vaccines, but I do have to say that cancer vaccines have not enjoyed the success that we've seen with other forms of cancer immunotherapy, such as immune checkpoint inhibitor monoclonal antibodies. I think in the field, people like to go where drugs are working. To date, that hasn't been cancer vaccines. We only have one approved vaccine, for prostate cancer, that was actually developed here in Seattle. But we haven't had more vaccines approved for other diseases. I think that's why they started that title with people flocking away from cancer vaccines, but there's a core group of people that have been steadily working to try to figure out how to make cancer vaccines a viable treatment option for people with cancer.

We know that vaccines work by triggering an immune response in our bodies. Are these vaccines designed to work in the same way?

Absolutely. In fact, that is one of the understandings that really brought us kind of a tipping point for cancer vaccines. We now know what portions of cancer are capable of stimulating the immune system. When you think of the Covid vaccine, we had to know what parts of Covid we could target the immune system so that would be effective. We now know for a lot of common solid tumors what portions we should target with a vaccine to direct the immune response to.

Including that, are there also other areas where you're starting to see new hope for the future development of cancer vaccines?

Definitely. Now that we know what to target the immune response to. One of the other big understandings over the last decade is the type of immune response you need to kill cancer. And unlike the vaccines we get for infectious disease, which really try to create an antibody response, we know that for cancer we need to stimulate a T cell response, a cytotoxic or Killer T cell response, that can directly kill the cancer. And then the final thing, I think, that you've seen with the Covid vaccine, is we have much better vaccine delivery technologies, like messenger RNA or DNA, that give the immune system an additional tweak.

Are there specific cancers that you're focused on?

Our institute is really focused on the common cancers that most people die from-- breast, ovarian, prostate, colon, and lung cancer. And we also have a bladder cancer vaccine in development. These are vaccines that would cover about 50% of all cancers diagnosed, and those cancers are responsible for about 50% of all cancer deaths.

How far away are you from being able to develop a vaccine for any one of those cancers?

With some of them, we're pretty close. We actually have vaccines in phase one and phase two clinical trials. Others of them are still in development, but we usually hope to get a vaccine into the clinic within two years of starting to work on it. We look at vaccines in three different ways. Using a vaccine to actually treat cancer – that's giving the vaccine to someone who currently has cancer. Usually, in that case, we team up the vaccine with other types of anti-cancer therapies. Then our largest programs are in vaccines to prevent cancer from coming back. In many of these tumors, take breast cancer, you can make the cancer go completely away, but at certain stages, or with certain types of breast cancer, you're at very high risk of that cancer coming back. I think vaccines will fit right into that niche of being used in patients who've received optimal treatment to prevent disease from reoccurring.

But a big breakthrough is within the last five years. Our group and others have started seeing if we could develop vaccines to prevent the development of cancers. We would target those for people at high risk, let's say people with a genetic mutation that puts them at high risk for developing cancer, or people who've had lesions that predispose you to develop cancer, like an adenoma predisposing you to develop colon cancer, for example.

It sounds like you've got more and more grounds for hope as you continue your work with your colleagues. I'm wondering what you need to make progress at this point on cancer vaccines.

I think the biggest thing we need is patients enrolling in clinical trials. Those are the real heroes. We can do everything in the lab, create a vaccine and manufacture it, and write a clinical trial. But if we don't have the right patient populations enrolling, it really slows down the work. And more and more, we’re identifying these targets. Vaccines are becoming or will probably be like precision medicine, where they're going to be targeted to a specific patient population. But that money, patients enrolling in clinical trials, and money to get the work through, those are the things that really speed up advancement and vaccine development.

As you know, vaccines have become a political battleground for quite a few people in recent times. Is that a concern for you, that just even having the term vaccine out there, or clinical trial, that people would shy away from it and not want to get involved?

I used to think about that, but we have a very important word before the vaccine. That word is cancer. In my experience, the fear of cancer trumps any fear of vaccines. We actually have lots of patients who are interested in cancer vaccines. Our issue is just having the right vaccine that a patient would qualify for. But we haven't had people turn us down over fear of vaccines because I think most people who are coming to us are really trying to survive their cancer, or improve their chances of surviving their cancer. So far, we haven't seen that phenomenon of being afraid to get a vaccine. And usually, the vaccines have many fewer side effects than something like chemotherapy, so people are pleasantly surprised at how easy they are to take.

When do you think cancer vaccines will become widely available? And who do you think could benefit from them first?

I think cancer vaccines will become more widely available within the next five to eight years. The reason why I say this is that if you looked at active clinical trials in the United States, clinical trials with cancer vaccines are pretty up there in terms of being common, with many people adding them to current immunotherapy for cancer.

The people who will first benefit are those who are undergoing cancer treatment, where people will use cancer vaccines to try to help boost the immune response even further with other immune therapies. I think we're also going to make traction with that group of patients where we're trying to prevent disease recurrence. Those are the two populations that I think in the next five to eight years, we'll see cancer vaccines becoming part of standard of care.

With that third group, where we're trying to develop vaccines to just prevent the development of cancer, and people who have not yet had cancer, I think we still have a little way. We might be talking about 10 years from now before we see a vaccine for patients at high risk for a particular cancer.

I'm wondering if you think that you will still be working in this field if and when these vaccines become widely available to the public. And I'm wondering what that would be like for you.

I will definitely still be working in this field. And it will really be a dream. I mean, when I started in this field 25 years ago the big question was, "Does the immune system have anything to do with cancer? Can cancer be recognized by the human immune system?" That was the big question. And just in that 25 years, we've gone from that being the major question, to immune therapies, those immune checkpoint inhibitor therapies, now being standard of care treatment for many types of cancers, and their sole function is to stimulate the immune system. So, I think we're very close to cancer vaccines following up on that success of those immune checkpoint inhibitor therapies. And to think that in one career, we went from zero to 100%. I mean, that's just indicative of how fast science and technology moves. It's been a ride, let me tell ya!

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