Recurrent Ovarian Cancer: Choosing a PARP Inhibitor

Bradley J. Monk, MD: I’ve been easy on you, Sharyn, but I’m not going to be easy on you now. There are these three indications for maintenance treatment after responding to second-line or beyond platinum. I’m not going to go through the SOLO2, Study 19, but they are not too dissimilar to NOVA and ARIEL3. The first PARP inhibitor that became approved in treatment was fourth line, and it was only germline. As Tom said, we have a regimen line of therapy earlier in rucaparib, two priors not three. And as Tom Krivak said, we now have beyond BRCA, we have an HRD [homologous recombination deficiency] molecular signature.

We have three treatment indications—I get it the labels are different a little—and we have three identical labels in platinum-sensitive maintenance treatment. So the tough question for you is, in the setting of overlapping labels, which PARP?

Sharyn N. Lewin, MD: That’s a great question. If you look at the hazard ratios on these trials, these PARPs are pretty similar when it comes to efficacy. It really boils down to safety profiles and tolerability. From personal experience, which PARP I’d use the most on trial or off trial, I do have my favorites, but the safety profile is what it boils down to.

Bradley J. Monk, MD: Tom Krivak, how about familiarity? Does familiarity play into that, or is it more safety?

Thomas C. Krivak, MD: You get familiar and comfortable with the PARP you feel is the safest. We’ve never had three drugs very similar come on in competition, so it’s been hard for us to figure out how to use it. I think it’s nice having choices. I agree completely with Sharyn in that it’s adverse effects. If somebody has really bad nausea/vomiting on olaparib, you can consider changing over to rucaparib or niraparib. If some patients are not as driven and may not want to take their medications as often, you have once-a-day dosing with niraparib.

I work in a large health system, and I think at some point it’s going to be cost-driven. We’re going to get two PARPs, and we have to decide which ones because we’re going to go back. I hope it never comes to one option because I completely agree with Sharyn in that they’re all not equal. The science of medicine is understanding these studies, and the art of medicine is taking each of these studies and applying them to the right patient so we get the patient to be on the drug for the longest period. That is the key.

Transcript edited for clarity.