For some reason, the major media have decided that abiraterone acetate is “a wonder drug” that is going to solve all of the problems of men with hormone refractory prostate cancer and maybe more. The following is a quotation from a story in today’s Los Angeles Times:
Dr. Glen Justice, director of Orange Coast Memorial Medical Center’s Cancer Center in Fountain Valley, noted: “What is exciting about this drug is that it had activity in both earlier and later stages of disease. . . . The question is: Can we take people that have a very aggressive disease that was caught early and increase the cure rate by using it upfront?”
The “New” Prostate Cancer InfoLink has little doubt that abiraterone is an exciting agent, and that it may well prove to have significant value in the treatment of prostate cancer. However, we feel it is important to note that we have all “been here before.” Abbott Laboratories’ atrasentan (Xinlay™) was supposedly a billion dollar drug, but it has not made it to market. Immunotherapeutic “vaccine” therapies have frequently been touted as revolutionary agents — but so far the best data available is only suggestive of a small survival benefit in some patients. On top of that, the majority of cancer therapeutics that make it into Phase III clinical trials never get approved because they either can’t show a therapeutic benefit compared to the current standard of care or they have adverse reactions that simply make their approval impossible.
To date, abiraterone has been carefully tested over a significant period of time in only a small number of the 250 people who have actually received the drug. Many of these 250 individuals have only been treated with the drug for days or weeks. The majority of a drug’s adverse reactions will only become evident after many people have taken it for a minimum of several months. Is it possible that abiraterone is really a very safe drug? Yes, of course it is. And we sincerely hope that the data currently available is substantiated in larger clinical trials.
It is worth noting that a detailed press release, summarizing all of the data presented on abiraterone (also known as CB7630) at the ASCO annual meeting in June, is available on the Cougar Biotechnology web site. This summary is a great deal less “wonder drug”-like that recent media reports would suggest.
The “New” Prostate Cancer InfoLink believes that the best and only way to find out if abiraterone is really as good as the hype is for eligible men to volunteer for the open Phase III clinical trial in hormone refractory disease as soon as possible. We encourage all eligible patients to consider enrolling in this trial. Cougar Biotechnology needs something like 1,150 men who have already failed docetaxel chemotherapy to enroll in this trial of abiraterone + prednisone or prednisolone compared to a placebo + prednisone or prednisolone. This means that a large number of men enrolled will not get the active drug. However, without such a trial we are not going to know whether abiraterone really works.
And another item. Some stories have implied (or even stated outright) that abiraterone will be approved by 2010 or 2011. The Phase III trial protocol on ClinicalTrials.gov is very clear that the projected date for completion of the study is June 2011. It would still take at least 6-12 months from that time for the developer to analyze the available data, submit that data to regulatory authorities such as the FDA, and get marketing approval if everything went without a hitch. We think it would be very surprising to see abiraterone approved any earlier than 2012 unless it shows some very significant clinical results in other clinical trials as well as in this pivotal Phase III study.
Finally … Does abiraterone really have potential much earlier in the disease state? Perhaps! There can be little doubt that Cougar Biotechnology and its advisors are looking carefully at the possibility of carrying out at least one Phase II clinical trial in men with hormone refractory prostate cancer prior to docetaxel chemotherapy, and perhaps a trial in men with a rising PSA post-surgery for localized disease. However, such trials come with big risks as well big potential for any drug developer. They may decide that their first priority (financially and commercially) is to prove the drug’s value in patients who have failed docetaxel, and that other opportunities have to wait.
Whatever turns out to be the case, The “New” Prostate Cancer InfoLink will be one of the first places where you can get the latest news about progress in the development of this drug.
Filed under: Drugs in development, Treatment | Tagged: prostate, cancer, abiraterone, hormone refractory
Being newly diagnosed with PCa and reading the “frenzy” about abiratrone as well as other clinical trial drugs and immunotherapies targeting “advanced” or hormone refractory PCa, I question why there don’t seem to be any drugs in clinical trials that target early stage disease that prevent or inhibit cancer growth and thus may preclude the need for one of the traditional initial treatments with their subsequent quality of life side effects.
It seems to me that research is focusing on either prevention (vaccines, diet, supplements) or advanced stage disease and that the large middle ground of early stage disease is not receiving much research attention. Or am I missing something here?
Dear Mr. Winkler: Your assessment of the situation is actually very accurate. The primary reason for this is the extended period of time that would be required to know whether a drug for early stage disease had actually worked.
A patient diagnosed with early stage disease who receives no treatment at all may take 5, 10, or even 20 years to progress to metastatic disease. Or he may progess to metastatic disease within a year. But for the vast majority of patients, there is no way to tell up front. The consequence is that the drug development company may have to commit to a trial that would last for a decade or more before they would know whether a treatment worked in early stage disease. Quite apart from the cost and the risk, the patent life on a new drug is only 17 years to start with. The patent could have run out by the time they got their drug approved.
As a consequence, what the companies look for is a drug that works in late stage disease (so that they can get it to market) and that can then be shown to work in earlier stage disease too, so that physicians can prescribe it while the definitive trials are being done. Abiraterone may prove to be a case in point.
Look around carefully. For example, a blog posting from earlier this month talks about the initiation of trials of Provenge in earlier stage disease. This is because the developer is now confident they will get an approval for relatively late stage disease some time reasonably soon.
With respect to preventive therapy (finasteride, dutasteride, selenium, vitamin D, etc.), the potential market size is much larger, and so the market risk becomes more worthwhile.
I interpret the frenzy to be similar to what happened with Provenge last year. It is due to there being so few trials, announcements, or breakthroughs for those of us with either advanced PCa or HRPCa. Any bit of news that might be possibly positive is latched onto and perhaps one could say “blown out of proportion.”
The bit of good that this has done in the UK is that PCa got another airing. Fortunately I had read the phase III inclusions and exclusions before the local radio station (BBC Radio York) rang me requesting an interview on air.
This is the kind of drug I will be likely to need myself in a another year or so. If there is an option in the future to try it before doxetaxel and its side effects, I’m sure many of us would jump for joy.
I am not that sure that with a PSA that rises quickly when it moves that I’d be prepared to stay on the trial for long if for any reason my PCa was not controlled by it or if I was one of the third on a placebo.
So the media story is good providing it is told with the caveats.
Dear David and Bryan: Thank you for your thoughts. We absolutely agree that the hope offered by any new drug like this is a good thing. It is the hype that comes with it that is the problem, and all too often the caveats disappear in the media’s need for a “sound bite.”
An article published in the UK on Sunday that is specific to abiraterone highlights several of the problems with the drug research system and how the press only magnifies the problems and sets up false expectations.