The panel of pharmacists share data for the recently approved subcutaneous pertuzumab + trastuzumab combination therapy from the FeDeriCa study.
Jacob Kettle, PharmD, BCOP: Beyond the biosimilars, there are also some variations to products we’ve had for a long time. The most notable of those to be recently approved is a combination of pertuzumab and trastuzumab that can be given in a single fixed-dose injection subcutaneously. Talk about a real departure from what we’re used to with 2 different IV [intravenous] infusions. This is a radical shift in terms of how this drug can be delivered. It goes without saying that there’s some definite advantage to patients when we talk about replacing that dual IV therapy with a single subcutaneous injection. I’m curious, what are the clinical hurdles you see with these molecules?
Allison Butts, PharmD, BCOP: As you said, there are a lot of benefits to them. We’ve got patients who drive a far distance. They drive around the parking lot trying to find a spot. They wait for their chemotherapy chair to open. They then sit there for several hours potentially and get their therapy. They tie up a chair for a long period of time that another patient may need to get their therapy started. There are a lot of issues like that. Some hurdles come into play with where the drug is given, who is paying for it, how you are monitoring that patient from afar, etc. There is a lot of push and a lot of the advertisement with this new drug therapy that’s available is about potentially giving it at home.
If we give it at home, we save the patient a lot of time and allow more chair time for our IV chemotherapy patients. There are benefits, but what’s the cost of that? Do we run the risk of patients having some compliance issues because they’re given more control over their therapy? Do we still run in with some infusion reaction potential? What kind of acute adverse effects will the patient potentially deal with? Are they premedicating appropriately at home? Those are a number of the issues that we have to deal with.
If the patient is getting the therapy on-site, there are still a number of issues that need to be dealt with, some of which we just mentioned with the biosimilar issue. You’ve got yet another product on your shelf that the patient could potentially use. It’s another drug to get prior authorization. It’s another drug to get consent for, so on and so forth. All those same issues largely apply. We need to educate the nurses to make sure they’re comfortable with how to administer this type of therapy.
It’s becoming more common but still a fairly novel idea to inject a monoclonal antibody subcutaneously. There is still a lot of work that goes into this, but it’s probably worth exploring given the benefits to the patient: their quality of life and their experience overall.
Jacob Kettle, PharmD, BCOP: You raise some good points. The data that resulted in the approval of this drug was from a phase 3 trial: FeDeriCa. I think I said that right. Correct me if I’m wrong since you probably know better than I do. It’s a study that was released at the San Antonio Breast Cancer Symposium this past year. This is predominately approved on pharmacokinetic data.
Basically, it showed noninferior trough levels of pertuzumab and trough levels of trastuzumab. In full disclosure, they did show that pCR [pathologic complete response] rates were similar between the 2 groups. We know how valuable HER2 [human epidermal growth factor receptor 2] therapy is. Again, it’s similar to the same kind of discussion when we talk about biosimilars. How do you cross that clinical bridge? We are taking a bit of an extrapolation when we base these leaps on pharmacokinetic data.
Allison Butts, PharmD, BCOP: Our institution [at the University of Kentucky] uses a fair amount of subcutaneous trastuzumab currently. For us in a number of other sites, jumping to a subcutaneous trastuzumab-pertuzumab combo is not quite a giant leap anymore because we have more comfort with subcutaneous therapy. One thing we still need to figure out is how we operationalize this. Do we give some of the doses on-site before clearing the patient to go home? Do we require that home health administer it versus the patient doing any kind of self-administration? How do we sort through those things and make sure the patient is still getting their curative therapy when we’re not able to control it as well?