Maintenance Therapy Selection and Use in Ovarian Cancer
A broad look at maintenance therapy selection and its use in ovarian cancer to improve patient outcomes.
EP: 1.Ovarian Cancer Patient Case: Prognosis and Molecular Testing
EP: 2.Maintenance Therapy Selection and Use in Ovarian Cancer
EP: 3.Considering PARP Inhibitor Maintenance in Ovarian Cancer
EP: 4.PARP Inhibition in Ovarian Cancer: Safety Profiles and Dose Adjustment
EP: 5.Recurrent Ovarian Cancer: Treatment Options and Maintenance Therapy
EP: 6.Ovarian Cancer: Future Directions in Care
Leslie M. Randall, MD: All of our patients who have ovarian cancer should be considered for maintenance therapy. Right now, we have 2 commercial options for maintenance and then we have clinical trial options for maintenance. Our HR [homologous recombination] deficient and BRCA-mutated patients really need to go on PARP inhibitor maintenance. And the question is do they receive that with or without bevacizumab [Avastin]? For patients who have HR proficiency, they have the option to continue on PARP therapy alone, bevacizumab therapy alone, or they’re a high priority for clinical trial development.
Determining which maintenance therapy to use is a big decision and there are many factors that play a role in this. First, as we just discussed, you need to know what your options are. Our options are PARP inhibitor, bevacizumab, the combination of the 2, or a clinical trial. What drives my decision depends on whether the patient had a response to their upfront treatment, so technically [a response] for PARP inhibitor therapy. Patients should have had a complete or partial response to their frontline therapy. For bevacizumab, there can be a stable disease situation. There doesn’t necessarily need to be a response but for PARP therapy we consider patients candidates if they’ve had a response to their frontline therapy. So that’s a big consideration. Next is the tumor type. Again, we’re talking about epithelioid tumors. The high-grade serous and the endometrioid tend to be the most responsive to PARP inhibitors. Those were included in the clinical trials so I would mostly consider those tumor types. Now having said that, if patients have a BRCA mutation or if they have an HR deficiency in either of those 2 tumor types or other tumor types, such as clear cell or mucinous, then I would consider PARP therapy as well. If patients don’t, if they have a non-high grade serous, non-endometrioid type without the biomarker, they’re probably better off receiving either bevacizumab maintenance or clinical trial. Those are going to be the minority of patients. The vast majority of patients are going to be high-grade serous endometrioid, half of those will have some measure of HR deficiency, and half of those patients will have a BRCA mutation. So we really have an enriched population that benefits from PARP inhibitors. Patients obviously should still be and have good performance status and be able to tolerate ongoing therapy. But that’s the beauty of maintenance therapy is that it’s not as toxic as chemotherapy and you can continue that for a long time to keep them in response to chemotherapy, to help prolong their response times and their progression-free survival times.
We know that maintenance therapy hasn’t had a quick uptake after the release of the clinical trials and I don’t think we really know what the reasons are behind that. I know the patients that I’ve seen that have been referred to me for consideration of maintenance or who have started maintenance and stopped. It’s mostly been just a lack of experience. Ovarian cancer is not common, especially in community practice. You may only see 1 or 2 ovarian cancer patients per year, especially for a medical oncology practice, those who have a special interest in gynecology, that maybe are more familiar with the data that has led to the approval of the maintenance therapies to include the PARP inhibitors. That’s what I think is probably the largest barrier, but I do think we have room for improvement in the uptake of maintenance therapy.
Transcript edited for clarity.