Value-based Considerations of CDK4/6 Inhibitors in the Treatment of Metastatic Breast Cancer - Episode 20
Caroline Block, MD, shares the process for inclusion in a pathway with multiple agents from one class and how to measure success of clinical pathways.
Caroline Block, MD: As far as the CDK4/6 inhibitors, which are used very commonly in advanced breast cancer, ER [estrogen receptor]–positive and HER2 [human epidermal growth factor receptor 2]–negative breast cancer—we first put palbociclib on the clinical pathways. That was approved first. As the other 2 CDK4/6 inhibitors were approved, we looked at whether to add them and what sort of differentiation to put into the clinical pathways.
When ribociclib came out, we certainly looked at it. It had similar efficacy to palbociclib. The concern was that it had some additional toxicity that palbociclib didn’t have. Since it didn’t add anything in the world of efficacy, it added liver toxicity, and cardiac toxicity was a bit higher, we decided not to add it to our clinical pathways. Providers can certainly use it if there’s a reason to use it: Sometimes there is. They have to go off-pathway to do it.
When abemaciclib came out, on the other hand, we did end up adding that as an alternative because the toxicities are so different. For someone who has a lot of pancytopenia on palbociclib or preexisting pancytopenia, abemaciclib can be a better option since it tends to affect the blood counts less. It can cause more GI [gastrointestinal] adverse effects, such as diarrhea, so that is certainly mentioned.
At the moment, we have palbociclib with various endocrine agents and abemaciclib, both monotherapy and with various endocrine agents on our pathways. But for ribociclib, people go off-pathway to use it.
We measure success for clinical pathways in a couple of ways. First, we have monthly reports that go to each disease center, mine being breast oncology, and that report will have, for the group as a whole what percentage of time people used clinical pathways. When you started someone on a new regimen, you went in and clicked through clinical pathways, said what was used, and completed that process. We obviously like to see a high utilization rate. We like to see that at least 80%. Then we’ll look at it for individual providers as well. As you might guess, some providers are excellent. They use it every single time. Others are a little less consistent, and we remind them about the importance of using it.
Then we also will look at the on-pathway rate. The usage rate is how often you click in and use it, and the on-pathway rate is how often you used what was listed in clinical pathways and how often you went off-pathway, such as using ribociclib or using the regimen I mentioned before: pertuzumab added to eribulin and trastuzumab. No one gets punished or reprimanded for going off-pathway, but we look at the reasons. We make sure they’re appropriate reasons, and then we’ll discuss that when we review pathways to see if there are things that we should be adding or that we should be doing differently.
For first-line, metastatic, ER-positive, HER2-negative breast cancer, although we had Taxol [paclitaxel] listed, we had a lot of people using capecitabine, so we discussed this. This was probably 6 or 8 months ago. The decision was that it was good to have capecitabine as an option as well. There are a lot of patients who didn’t want to start with IV [intravenous] chemotherapy. They didn’t want to lose their hair initially. Some of them had neuropathy from other treatments and were worried about neuropathy. Based on the off-pathway rates being so high for capecitabine, we ended up adding that as a first-line mention. That’s an example of how we will look at that data and use it to make our clinical pathways better.
We evaluate our clinical pathways on a regular schedule, and we will have additional meetings whenever new data or drugs come out. We typically have, in breast oncology, 3 meetings a year, and most groups have between 2 and 4 meetings a year routinely scheduled. We tend to schedule 2 of them after some of the big meetings like ASCO [American Society of Clinical Oncology Annual Meeting] and the San Antonio Breast Cancer Symposium, when breast treatments often are announced. We then have a third meeting mid-year to look at our pathways overall. We will set up additional meetings when new drugs come out. Typically, with a few weeks’ notice, we can set up a meeting to review the new drug approval and where and how we should use it.
We’ve had maybe 4 meetings already this year. We’re only in June. One was a regularly scheduled meeting after the San Antonio Breast Cancer Symposium. One was to discuss 3 new drugs that came out: tucatinib, trastuzumab, deruxtecan, and sacituzumab all were discussed. At the extra meeting, we recently created an inflammatory breast cancer pathway, so we had a few meetings about that: 1 initial brainstorming meeting and another to finalize the inflammatory breast cancer pathway.
We will add extra meetings anytime there’s a new drug or new study we should incorporate or if we’re trying to build a pathway for a new treatment situation, such as inflammatory breast cancer. We have meetings often. We have standing meetings we can add to this, or we can substitute the agenda for a clinical pathways discussion instead of a standing meeting. That’s what makes it easy for us to do this.
For the clinical pathways leadership for the institute as a whole, David Jackman is a thoracic oncologist, and he heads our clinical pathways team. He has worked with payers both regionally and nationally to look at how the pathways help guide our treatment to create more cost-effective treatment, and more guideline-based treatment. The individual physicians such as myself, even though I’m the breast oncology pathways leader, are less involved with that. From an institutional level, Dave Jackman and some of the other leadership at Dana-Farber [Cancer Institute] have been talking to different payers, who are excited about the use of clinical pathways for that particular aspect.