Video: Provenge: Eligibility, Effect on PSA, & More | Ask a Prostate Expert, Mark Scholz, MD
Ask a Prostate Expert | Transcription
Alex: Dr. Scholz, which men are eligible for Provenge? Like, there's so many different types of prostate cancer, so where does the Provenge come in when it comes to sequencing?
Dr. Scholz: So, Provenge would probably be used a lot more than it is used because it is pretty expensive. So, your question really addresses when will insurance pay for it, and the answer to that is men who have at least manifested one metastatic site. So, a cancer that spread to a lymph node or a spot on the bone are required for people to be eligible to get this medicine. In addition to that, men have to have been previously treated with hormone therapy, Lupron, and that hormone treatment has to have stopped working. So, that would mean that someone has a low testosterone and their PSA is creeping up. So, if they meet those two criteria, then insurance will pretty much cover Provenge without any arguments.
The sort of sad thing that I see is that oftentimes Provenge isn't used right at that inflection point when the PSA starts going up in men that are taking Lupron, and for some reason, I don't know whether people forget Provenge or they... I don't know what they're thinking… But, you know, people allow the cancer to become very advanced, and when, you know, the PSA is up around 100, the benefit of trying to go to strengthen the immune system at that point is quite reduced. You know, it might add a few months to your life expectancy, but in the patients who start with lower PSAs, we try and start with the PSAs less than 5, but in the studies showing that men started with a PSA less than 20, they had 13 months of additional longevity. So, that was a big difference when we start early, and so we're always on the lookout for men that have had at least one metastatic lesion and who are developing a rising PSA when they're on Lupron.
Alex: So, I've read that Provenge does not affect PSA. Like, it doesn't lower PSA when it comes to getting the treatment. I've talked to patients who have been a little bit surprised by that. Can you tell me why and kind of talk about why we know it works?
Dr. Scholz: Sure, the PSA probably is "altered." In other words, while PSAs don't typically decline. I have seen them decline from Provenge, but there is something called the PSA doubling time and PSA rate of rise tracks along with how fast the cancer is growing, and some studies done by Eric Small up at UCSF shows that in the men that received Provenge, that the rate of rise was retarded or slowed down. So, the immune system doesn't seem to work at least with Provenge so much by eradicating the cancer. What it seems to do is it seems to inhibit the progression of the cancer, and the cool thing about it is that the treatment only takes six weeks to give but once you alter the immune system, the immune system has a memory and it keeps working on an ongoing basis after the treatment is stopped. So, this would be another reason to get started earlier. So, if someone has a predicted life expectancy of a year, gets Provenge and lives a year and a half, he was only exposed to that Provenge for a year and a half. If someone is treated at a much earlier stage when his life expectancy is five years, the immune system will keep working throughout that five year period and there'll be an ongoing effect over a longer period of time.