Prostate Cancer Treatment: Incorporating Micronized Abiraterone into Clinical Practice

For patients with prostate cancer who require therapy, micronized abiraterone provides many advantages. In this Urology Medical Perspectives series titled “Clinical Use of Micronized Abiraterone for Patients with Prostate Cancer,” Benjamin H. Lowentritt, MD, FACS, a urologist at Chesapeake Urology, discusses the role of micronized abiraterone in the treatment paradigm and provides clinical insights on incorporating it into clinical practice.

Urology Times®: How did the FDA approval of the micronized form of abiraterone impact your clinical practice?

Benjamin H. Lowentritt, MD, FACS: The approval of the micronized form of abiraterone was interesting. There’s a bit of unfortunate timing here because it was approved around the same time as the loss of the patent of the original abiraterone. So you had the branded original formulation of abiraterone, a newly branded form of micronized abiraterone, and generic forms, which muddied the waters. But over time, we’ve been able to get experience with the micronized form and see the potential advantages in specific patients, and I think our use is only going to expand as we cater to specific patients and their needs.

Urology Times: Along those lines, in which patients do you strongly consider using the micronized form? What are the disease factors, patient factors, and medication factors that might lead you in one direction?

Benjamin H. Lowentritt, MD, FACS: Deciding when to use the micronized form of abiraterone can be a little bit complex. There are a number of factors that come into play. There are many patients who have a really hard time sticking to the regimen of taking abiraterone without food, with a very empty stomach. It might be because they just don’t like taking medicines on an empty stomach or are having trouble remembering to always do it that way. They might have concerns over the increasing dose or increasing bioavailability of traditional abiraterone when taken with food. We have seen some patients who have tolerability issues and safety concerns that I think are occurring because they’re often not taking it on a fully empty stomach. These are patients who might benefit from the micronized abiraterone.

I’m also beginning to see that as we go to patients who are having a strong response to therapy and are going to be on therapy for a really long time, both because of the overall increased dose that’s needed of the abiraterone and because there’s variability in bioavailability from the traditional abiraterone, I have some concerns about long-term use. People can be on these therapies for multiple years now. I have a number of patients for whom I’m considering micronized abiraterone who are already doing well but having some slight tolerability concerns on traditional abiraterone.

In addition, we’re seeing the increased use of abiraterone in other parts of the treatment paradigm. I think it’s totally appropriate to consider the micronized form in anyone whom you think may benefit from the micronized form.

Urology Times: What adverse events do you see with the micronized and the traditional forms of abiraterone? What are some strategies that you have found to be successful with mitigating or managing these?

Benjamin H. Lowentritt, MD, FACS: With either formulation, there are oftentimes adverse events that are drug specific and those that I would consider more steroid hormone concerns. With abiraterone, we worry about adrenal insufficiency, whether it’s leg swelling, blue streaking, or some of the severe fatigue that comes with adrenal insufficiency. You can even see some of the skin changes if they’re not taking their steroids well. A lot of times, that’s just making sure they’re on the appropriate dose of steroids.

In addition, there are some specific safety concerns with abiraterone. There are some cardiac concerns. We see that in all types of hormone-mediated therapies, that you have to be concerned about the cardiac adverse effects. In addition, there are very specific liver enzymes that need to be monitored. And usually earlier on, but even in delayed fashion, you can see impaired liver function that may require dose reduction. I think some of this is related to differences in bioavailability, where you may be getting different kinds of absorption day to day and effectively having different doses in the body, especially if someone’s taking the traditional abiraterone and they’re not great about taking it without food. In those patients, I really consider the micronized form because it has a more predictable bioavailability range. Even if you dose reduce, which is the typical thing that I would do in these cases, you really know they’re getting the accurate dose with the micronized form. For people who are having difficulty and require dose reductions, I definitely consider the micronized form as an option for them if they’re otherwise having a really good disease response to the abiraterone.

Urology Times: In your practice, what has the experience been with prescribing micronized abiraterone? Have you seen increased adherence to the drug? Has the quality of life changed compared with other options in this space?

Benjamin H. Lowentritt, MD, FACS: My personal experience with the micronized form is impacted by all the realities that we have when treating any of these patients. Some of this is regarding whether we can actually get the drug to the patient. And because there is a generic form out there, there are times when it’s difficult to get a branded medication to those patients. That being said, we’re able to get many patients with all different types of insurance on the therapy. And I really believe that the ability to take it at any time, regardless of meal time, helps with adherence. We’re seeing patients tolerate it well. And if we need to dose reduce, we know with confidence that we’re going to get that dose reduction and that it’s not a concern about the bioavailability from somebody eating. It gives us the confidence that we’re getting exactly what we want. And as long as we’re able to negotiate the challenges of all patients with advanced cancer treatments as far as getting their medication, it’s a really good option.

Urology Times: How do you communicate with your patients about micronized abiraterone? How does shared decision-making work in terms of selecting an ADT [androgen deprivation therapy]? Are patients aware of micronized abiraterone? What kind of information or resources do you typically share with them when helping them decide what treatment to go with?

Benjamin H. Lowentritt, MD, FACS: Because there are so many options available for the treatment of advanced prostate cancer, we have some very in-depth conversations with our patients that tend to be very heavily led by the physician. I don’t necessarily expect my patients to be completely up to date with all the options, so it is important for us to discuss all of those options with the patient. That includes a conversation about abiraterone, and should include a discussion overall about the different forms of abiraterone and the different combinations of therapies. There are patient education materials online that we use that are provided by the different companies, but I think that conversation is really important in general. The patient is going to go with what the doctor or the non-physician provider recommends. It’s very important to educate and to engage in shared decision-making.

Part of the discussion is that there are patients looking to avoid steroids, even though it’s a low dose of steroids and very well tolerated in general. We need to educate them. But that can be a dealbreaker for some patients. I think in general, though, educating patients on the mechanisms, how it’s compatible with general ADT, the outcomes that have been shown in multiple trials, and the benefits to survival are really important for helping patients make their decision and have the most confidence in the treatments that they choose.

Urology Times: How do you typically monitor and follow up with patients?

Benjamin H. Lowentritt, MD, FACS: It is very important to set up a good monitoring and maintenance protocol with these patients. I’m fortunate that I have a great team around me, including some advanced practice providers that help with this. But whether it’s you or another provider in your practice, it is really important to know what you have to monitor. With abiraterone, it’s recommended that we check pretty regular generalized labs early on, both looking at their basic metabolic panel to look for changes in some of their electrolytes, which can happen especially if the steroid regimen isn’t perfect from day 1, and also liver function. And then gradually, we do less of that.

Many of these patients are still being seen every month or every 2 months for ongoing monitoring, their bone health, or other concerns that we may have. We frequently check bloodwork and include those specific tests to look at electrolytes and liver function. It is important to build that in. All of these patients need more monitoring just because this is a significant disease. However, once they’ve been stable for some time, we’re able to stretch those out a little bit further. But it’s important to establish that the patient is doing really well before you ease up a bit on the maintenance.

Urology Times: What clinical pearls would you like to share with community-based colleagues?

Benjamin H. Lowentritt, MD, FACS: Thank you very much for the time. The major thought that I have about abiraterone in general is that sometimes it’s easy to forget about a medicine that’s been around for a while and has gone generic. Especially with the micronized form that’s also available, we have to continue to put this at front of mind. The combination therapies that are out there, the use in adjuvant and other forms and stages of the disease, I think it’s still a great option for us. We’re very comfortable with using it, and the ability to not have to worry about taking it with food is really significant for the micronized form. It’s important to stay on top of everything that’s new but not forget those things that we know work really well that are a little older. I encourage you to continue to be educated about abiraterone, make sure you’re still comfortable with it, and to build those protocols in your offices to get the best results for your patients.