Ola Landgren, MD, PhD: What about the safety data? The immunoglobulin G drops with all these fantastic drugs because partly because they find the normal plasma cells. With the use of bispecific antibodies, [and the] need for IVIG [intravenous immunoglobulin], antibiotics, what happens in the outpatient setting?

Dennis Verducci, APRN: This is a great question. In the outpatient setting for patients on these bispecific antibodies, 1 thing we commonly see is that the patients are hypogammaglobulinemic. For that, we always start our patients on immunoglobulin G. We also put patients on prophylactic antibiotics to prevent pneumonia and upper-respiratory infections as well as antivirals.

Ola Landgren, MD, PhD: In our program, we follow all the protocols. The majority of clinical trial protocols these days recommend giving IVIG if the immunoglobulin G levels go under 400 mg/dL. To our knowledge, no randomized trial has definitively proven that. But that seems to be where many of the protocols are. As for the antibiotics, there’s a lot of controversy there as well. We talk about opportunistic infections, pneumocystis. You could do Bactrim [trimethoprim, sulfamethoxazole] on days 1, 3, and 5, and most of the protocols recommend that. Then there’s Levaquin [levofloxacin]. Of course, if you start thinking about that, is it going to be for a fixed duration in the beginning? Is it going to be continuous treatment? In our program, we haven’t reached a consensus internally. Is that right, Ben?

Benjamin Diamond, MD: That’s absolutely correct. We discuss this frequently because it’s always an evolving situation, but those are the big players. We’re using an antiviral, we’re using Bactrim, and we’re using Levaquin and IVIG. For each patient, we always have to readdress whether it’s time to continue those drugs or peel stuff off.

Ola Landgren, MD, PhD: Thank you for reemphasizing the use of an antiviral. I didn’t say that because that’s something we’ve agreed on. But for the others, IVIG—I think we agreed to 400 mg, but should you do 500 mg or another number? That’s what individuals are on the fence about. And for sure, antibiotics. But from what I’ve seen, we’re increasingly using Bactrim on days 1, 3, and 5. We aren’t implementing the other antibiotics at this time. That may change in the future. Is that right, Dickran?

Dickran Kazandjian, MD: It depends. Some of us are adding Levaquin for the first cycle. Infections tend to be higher during that first cycle. Otherwise, as long as we’re thinking about it, checking the laboratories, and having a low threshold to add this prophylaxis, that’s the way to go.

Ola Landgren, MD, PhD: When I’ve been attending the inpatient service, I’ve seen that patients can drop quite profoundly in the absolute neutrophil counts if you give a dose of a bispecific antibody. Even within 24 hours I’ve seen big drops. Is that something you’ve seen also, Ben?

Benjamin Diamond, MD: Yes, I’m glad you brought that up. We’re seeing that it’s not for every patient, but some do have a profound neutropenia, especially right after that first dose, to the point where a lot of patients are getting prophylactic growth factor when they’re in the hospital.

Ola Landgren, MD, PhD: There are many questions where we don’t have results from definitive studies. This is an area where we need to work together, and clinicians who treat patients with these fantastic drugs need to be on top of the game so patients don’t end up with infections that could be life-threatening. That’s very important.

Transcript edited for clarity.