We also heard updated data from the LATITUDE study today. LATITUDE was a trial of abiraterone and prednisone in M1 hormone-sensitive prostate cancer compared to androgen deprivation therapy plus placebo. We’ve heard positive presentations of this data previously, and this is now the final analysis. Unsurprisingly, this has shown confirmation of the overall survival benefit and we’ve also seen unsurprising, but now more mature outcomes in terms of the other secondary inputs.
One of the most interesting pieces of information to come out of today’s presentation though was the concept of PFS2. This is the time from initial randomization on the study, to progression of disease or death on the treatment after the trial therapy. This is important because we are interested in improving outcomes for patients across the entire course of their treatment, and if we bring a treatment early in the treatment course, we need to make sure that’s not compromising the efficacy of subsequent treatments. So we managed to get some reassurance on that point today by seeing that not only was PFS2 not compromised by early use of abiraterone and prednisone, but actually seen to be enhanced. So this is very important information. Not many clinical trials are collecting this information, and I think this is probably going to be something that’s important to bring into future clinical trial design.
The other issue about LATITUDE though is where abiraterone and prednisone now come into the treatment paradigm in the setting of healthcare systems that are constrained by costs. In some part of the world, abiraterone is easily available and cost is not a major consideration, and so it’s now being taken up as a frequent preferred option in this clinical setting. But there is an alternative, which is docetaxel chemotherapy. That’s a course of 6 cycles of intravenous treatment. No patient gets up in the morning and says I’d really like to have intravenous chemotherapy today, so it’s no surprise that most patients will opt for the oral therapy. However, 6 cycles of docetaxel against two or three years of abiraterone therapy certainly needs to be weighed up in terms of healthcare resources and overall costs. So until we have easy access to affordable abiraterone, I believe that docetaxel is still a valid alternative to be thinking about.
Another point is that we did also see activity of abiraterone and prednisone in patients with low-volume or low-risk disease. That does not seem to be the case for docetaxel, and so it may well be that abiraterone is a preferred option for patients with low-risk disease.