Pharmacist Role in Breast Cancer Treatment
Heather Moore, CPP, PharmD, highlights key contributions from pharmacists in breast cancer treatment and identifies current unmet needs in the treatment landscape.
Heather Moore, CPP, PharmD: Oncology pharmacists have a pretty significant role in the setting of oncology. First, thinking about toxicity management. I always say we’re fitting the drug to the patient. With all of our targeted therapies that are being FDA approved, a lot of them have really significant adverse effect profiles. It’s really important that as pharmacists we’re able to help in terms of supportive care measures, in terms of dose modifications, thinking about when we may dose hold vs dose reduce. But along those lines, also thinking about monitoring. That may look like lab monitoring, thinking about [electrocardiogram] monitoring for some of our therapies, hyperglycemia monitoring, thinking of alpelisib. As our agents become more complex and as their adverse event profiles become more complex too, so does the supportive care that goes around those patients to ensure that they’re maintaining on their therapy. As I mentioned, in thinking about dosing strategies, that’s important too. Thinking about dose escalation or maybe starting a patient at a slightly lower dose if you’re concerned for tolerance and doing a dose escalation, but also thinking about dose modifications maybe on how they’ve tolerated a therapy. Going back to CDK4/6 inhibitors, and we need to do a dose reduction vs a dose hold if a patient is neutropenic and [considering] where they are in their cycle. Importantly, as we’re pharmacists, drug interactions. As we’re doing more oral-targeted therapies, most of these agents are CYP3A4 substrates. Some of them may be inhibitors themselves or going through other pathways. It’s important that we know how these drugs are metabolized when we need to do dose reductions or perhaps modify other therapies as patients also have more other chronic diseases that are in the setting of their diagnosis. We need to be mindful in terms of how we’re getting along with those drugs. Thinking about perhaps patients who may have a cardiac history or other comorbidities and how we make sure that all of their therapies are essentially playing well together.
There are several unmet needs that currently are taking place in breast cancer. I’ll start this by saying we’ve certainly gotten better at it, but identifying patients who may or may not benefit from a particular therapy in an effort to ensure efficacy but also spare toxicity. We’ve gotten better at this, and we’re thinking about chemotherapy. Thinking about [phase 3] TAILORx [NCT00310180] and RxPONDER [NCT01272037] [trials], we’ve gotten better at determining who actually needs chemotherapy, who can we spare chemotherapy, and we’ve gotten better at using targeted agents. Patients who may have say, ESR1 mutations or PIK3CA mutations, we’ve have gotten better at targeting cancer. But we need to take it one step further and think, okay, who that may have an elevated PD-L1 will actually benefit from immunotherapy? That’s something to think about. Thinking about pathways of resistance, but also thinking about de-escalation of therapy. Are we able to cut back on some of the therapy that we’re giving patients? An excellent example of this is the ongoing [phase 2] STOP-HER2 study [NCT05721248], which is looking at stopping trastuzumab in patients who have been on maintenance therapy in the metastatic setting. Then, as always, thinking about accessibility and affordability of treatment options for patients. It’s not helpful if they don’t have access or if we’re having issues in terms of them maintaining on therapy. That’s always something that’s important.
Transcript is AI-generated and edited for clarity and readability.
