Navigating Current Prostate Cancer Therapies

For pharmacists managing patients with prostate cancer, it is important to be judicious about what treatment you are going to use, when you are going to use it, and on which patient, according to a session at the ASHP (American Society of Health-System Pharmacists) 54th Midyear Clinical Meeting & Exhibition in Las Vegas, Nevada.

Steven Ludlow, PharmD, BCOP, BCPS, clinical specialty pharmacist, elaborated on the background of prostate cancer in the session, “Navigating Evolving Treatment Strategies for Prostate Cancer,” including the pathology, epidemiology, and screenings. Specifically, with prostate cancer screenings, there is an emphasis on finding a mutual decision between the provider and patient.

“There are many organizations that everyone wants to be involved in directing and trying to help with prostate cancer screening,” Ludlow said. “But between them all, there is not a clear consensus on most aspects of the guidelines.”

Once a diagnosis is made, a Gleason score used to be the most common way to look at prostate cancer, and to determine the aggression level of malignancy. Now, grade groups are more accurate of what is happening in the patient, and builds upon on the Gleason score. Genetic testing, germline testing, and somatic tumor testing are also used, depending on the level of aggression, and life expectancy of the patient.

Since 2004, the FDA has approved different treatments for advanced prostate cancer, adding almost 2-3 indications per year for the past 15 years, according to Ludlow. Many patients are offered conservative treatments, such as observations and active surveillance, for low risk localized disease. Each treatment is targeted for a different age group, but is not meant for an overall cure.

“The idea behind this is that we’re avoiding all of the collateral damage from therapy, and simply saying ‘we’re going to look, we’re going to intervene if symptoms persist or impending issues, we’re going to swoop in and get control of disease,’" Ludlow said. “But we’re not going for functional cure because we believe that the disease state is secondary to one of the previous comorbidities or end-of-life.”

A patient may go through Androgen Deprivation Therapy (ADT)- agonism or antagonism. ADT Agonism includes leuprolide, histrelin, goserelin, and triptorelin, which inhibits the production of testosterone and dihydrotestosterone (DHT). In comparison, ADT Antagonism includes degarelix, inhibiting the activation of the axis suppressing production of testosterone and DHT. Both therapies’ adverse effects include hot flashes, depression, fatigue, cardiovascular events, and metabolic complications.

When it comes to treatment decisions, it can only be determined by patient factors. This may include presence or absence of metastasis, acceptance of treatment toxicity, expected survival, and any previous therapies completed. PARP inhibitors have been described as an evolution in treatment decisions, with Ludlow saying that, “Looking at mutations in the cells, we can find things to target. These targets are things that we have had active agents against.”

Katie P. Morgan, PharmD, BCOP, CPP, clinical pharmacist practitioner, covered the practical management for patients with prostate cancer, including continued education, medication therapy management, supportive care, adverse effect management, and financial toxicity. In more detail, Morgan covered how to manage “manopause,” such as different interventions of fatigue, hot flashes, and erectile dysfunction. For example, to tackle extreme fatigue, Morgan recommends patients with ADT to incorporate exercise into their lifestyle among other treatment options.

“Standard exercise for 30 minutes a day, 5 days a week, is what really can help patients maintain their level of stamina and activity,” Morgan said. “And there have been specific trials in patients on ADT that show that exercise can increase muscular strength, cardio and pulmonary fitness, functional task performance, lean body mass, and fatigue.”

Bone health is another crucial area of prostate cancer, which includes treatments such as denosumab, zoledronic acid, and alendronate that are known for their safety and efficacy against further bone damage. To prevent osteoporosis in patients, Morgan suggests all patients consume calcium and Vitamin D daily.

“All patients who have prostate cancer, especially on ADT, should be on Vitamin D, whether that’s just for osteoporosis prevention or supportive care for being on one of these modifying agents,” Morgan explained.

With the number of treatments available, it is important for pharmacists to realize which options are appropriate for their specific patient. For example, docetaxel is a lower costing option that is completed through a 6-cycle process followed by observations. However, abiraterone is a continuous treatment until the patient progresses, sometimes at a higher cost, and not ideal for a patient with severe issues, such as uncontrolled heart failure.

To conclude, Morgan went into the medication access and adherence in prostate cancer care, explaining that all medications have to come from a specialty pharmacy due to the cost and complexity of oral medications. There are barriers that come with access to these treatments, such as delays in medication initiation, making the process much more complex. Morgan explained the issue with Medicare in particular.

“Federally funded programs, like Medicare, make these patients ineligible for a lot of these assistance programs. They are not eligible for co-pay cards, and sometimes not eligible for grant funding. So it’s really difficult to navigate, especially when most of our patients are on Medicare because they are 70-80 year old patients,” he said.

A clinical pharmacist workflow model was presented by Morgan, showing the steps taken from initiation to followup.

“The physician and the pharmacist can be involved in diagnosis and treatment,” Morgan said. “I recommend that if you are involved in these decisions, to do that drug interactions assessment up front before the drug is chosen.”

In addition, as a pharmacist, making sure the correct medication is sent to the pharmacy, and continuing to teach the proper education are just 2 of the ways the pharmacist can maintain a strong relationship with their patient.

“These patients are going to be on these medications for several years, so it’s important to keep visiting with them when they come to the clinic to make sure they’re not having any compound toxicity, or worsening toxicity, what can we do to help them, and more,” Morgan said.

REFERENCE

Ludlow S, Morgan K. Navigating evolving treatment strategies for prostate cancer. Presented at: American Society of Health-System Pharmacists 54th Midyear Clinical Meeting and Exhibition; Las Vegas, Nevada: December 8-12, 2019.