Until recently I was not changing therapy for patients who only achieved a PR. But recent data suggest that patients achieving a VGPR prior to transplant have improved progression-free survival and overall survival, so I would consider switching treatment. If I have patients referred to me who have started with a bortezomib/dexamethasone or lenalidomide/dexamethasone regimen and have barely achieved a PR, I would switch to either CRd or RVD. Patients to whom I have administered CRd are either in VGPR or close to VGPR, so I don’t have to make that choice.

My decision about whether to switch therapies would depend on different variables. If a patient has high-risk disease, like 17p deletion or t(4;14), and only achieves a PR with RVD, the patient will have an adverse prognosis unless treatment is aggressive.

For a patient in this scenario, I would switch to VCD or CyBorD. We have had good results going from VCD to RVD and vice versa. If that doesn’t work, I would take a more aggressive approach because we are considering the patient for a transplant. We usually don’t need to consider carfilzomib or pomalidomide in these situations. We like to reserve them for after transplant.

Some transplanters believe that achieving a VGPR before transplant is important. I’m not sure that is always necessary. I have patients who have gone into complete remission even though they only had a PR prior to transplant. We have evidence that a transplant would benefit patients who do not have a PR. So I will allow some patients who haven’t quite achieved a PR to go to transplant. But I do want them to demonstrate some chemo sensitivity. If a patient who is at standard risk and has indolent disease achieves a 40% response, I’m more comfortable taking that patient to transplant than the patient with high-risk disease for whom depth of response is more important.

We do not switch therapies. In France, if the patient is in PR, we move to high-dose melphalan and stem cell transplantation followed by consolidation.

No, I would not switch therapies for this patient. I would move to high-dose melphalan after that.

I have changed therapies for patients in this situation. The goal of induction is to take the marrow involvement down to less than 15% as quickly as possible. A small subset of patients do not respond to induction treatment. These are patients with primary refractory disease, and those are the ones who I would switch to a different therapy so that they achieve the best possible remission.

About 20% of patients will not achieve the desired response prior to transplant. I would switch these patients to a different regimen. If I’m using RVD and I’m not seeing the desired response, I would consider switching to CyBorD.

Yes, I would switch therapies. I believe the goal should be a minimum of a VGPR. I would at times consider adding something like cyclophosphamide to RVD in this scenario.