Oncology Nurses' Guide to FDA-Approved Iberdomide: Q&A With Surbhi Sidana

The recent FDA accelerated approval of iberdomide (Zenbexus) marks a paradigm shift in relapsed or refractory multiple myeloma (RRMM) management. As the first approved agent in the cereblon E3 ligase modulator (CELMoD) class, this oral option—evaluated in the Phase 3 EXCALIBER-RRMM trial (NCT04975997)—offers a highly potent mechanism to overcome historical immunomodulatory drug resistance.

To understand what this means for frontline clinical workflows, Oncology Nursing News spoke with Surbhi Sidana, MD, Associate Professor of Medicine at Stanford University and chair of the American Society of Hematology’s Committee on Communications.

In this Q&A, Sidana highlights how the oral administration of iberdomide expands treatment equity for frail and rural patients who cannot regularly travel for center-based cellular or bispecific therapies. She also outlines critical clinical pearls for oncology nurses, including demystifying minimal residual disease (MRD) monitoring, navigating the restricted ZENBEXUS Risk Evaluation and Mitigation Strategy (REMS) program, and proactively managing severe early-cycle neutropenia.

How will the oral route of iberdomide reshape care and expand access for rural or frail patients who face structural barriers to receiving center-based CAR T or bispecific therapies?

Having an oral mode of delivery, a pill a patients can take, makes it very convenient for patients who live very far away in rural areas from a clinic. They can't go in every week for their injections, or they can't relocate, or someone who's very frail is not a candidate for CAR T or bispecifics, so it increases access for newer treatments for our patients who may not have otherwise access to these immunotherapies for various reasons.

What is the most effective way for oncology nurses to explain the clinical and prognostic significance of achieving MRD negative status to patients who are tracking their responses to the therapy?

MRD negative status, or minimal residual disease, or measurable residual disease negative status means just with a very sensitive test that's currently done in the bone marrow — for the future, we hope we can have blood-based assays, but right now, it's a bone marrow biopsy-based test —we can detect as little as one myeloma cell in a million or 100,000, depending on which assay we use. It's just telling us that your myeloma levels are at a very, very low level. It's prognostic information. It tells us that the likelihood of relapse in the near future is low, that patients are likely to do very well, and also more and more it's helping us make treatment decisions; it's helping us make decisions to stop therapy, or if someone's very high risk and they're still MRD positive, even escalate therapy. But it's just a very sensitive test. It gives us much more information at a deeper level than just blood and bone marrow can.

What are the most critical monitoring and education strategies nursing teams must implement regarding this regimen's higher risk of neutropenia and its stricter REMS program requirements?

The REMS program requirement is very similar to lenalidomide and pomalidomide, and a patient needs to be enrolled and answer their questionnaires. Men cannot father children; they have to use contraception and similar things for women who are of childbearing potential, it really goes back to the days of thalidomide, which resulted in birth defects, and these are just analogs of that drug. So, we just have to be very careful about that. But this is something we're used to for two decades in myeloma, so it's not going to be a practical barrier. It's just education and enrolling in that program, and then of course the things that we really need to watch out for in terms of side effects are twofold: risk of low blood counts in the beginning, especially low neutrophil count, and we need to be very watchful for that in the first two or three cycles because the risk is greatest then. Maybe we want to check blood counts every week for these patients in the first cycle or two, or every other week. Infections are also common in these patients, including severe infections. So, when someone's getting an infection, hold treatment, treat aggressively, and this is something we are very used to in myeloma.

References

1. Food and Drug Administration. FDA grants accelerated approval to iberdomide with daratumumab and hyaluronidase-fihj and dexamethasone for multiple myeloma. Food and Drug Administration website. Published August 13, 2026. Accessed August 18, 2026. https://www.fda.gov/drugs/resources-information-approved-drugs/fda-grants-accelerated-approval-iberdomide-daratumumab-and-hyaluronidase-fihj-and-dexamethasone
2. Bristol Myers Squibb. U.S. Food and Drug Administration Accepts Bristol Myers Squibb's New Drug Application for Iberdomide in Patients with Relapsed or Refractory Multiple Myeloma. Press Release. Published February 17, 2026. Accessed August 18, 2026. https://news.bms.com/press-releases/press-release-details/2026/U.S.-Food-and-Drug-Administration-Accepts-Bristol-Myers-Squibbs-New-Drug-Application-for-Iberdomide-in-Patients-with-Relapsed-or-Refractory-Multiple-Myeloma/default.aspx