Isatuximab

Isatuximab is a humanized monoclonal antibody directed against CD38, a cell-surface protein highly expressed on many myeloma cells. By binding to CD38, isatuximab induces tumor cell death through mechanisms including antibody-dependent cellular cytotoxicity, antibody-dependent cellular phagocytosis, and complement-dependent cytotoxicity, and it can modulate the enzymatic activity of CD38 in the tumor microenvironment. It is used in combination regimens to enhance anti-mueloma activity and to overcome resistance to other therapies.

In the United States, isatuximab is approved for relapsed or refractory multiple myeloma in combination with pomalidomide and dexamethasone for adults who have received at least two prior therapies, and in combination with carfilzomib and dexamethasone for adults who have received at least one prior therapy. It is marketed under the brand name Sarclisa by Sanofi and has been approved in several other jurisdictions for similar regimens.

Administration of isatuximab is by intravenous infusion, with dosing schedules that depend on the chosen combination regimen. Premedication with antihistamines, acetaminophen, and corticosteroids is commonly used to reduce the risk of infusion-related reactions, particularly with the first infusion. Infusion times may shorten over subsequent administrations if well tolerated. Safety monitoring includes tracking cytopenias and infection risk, as well as other common anti-myeloma–related adverse events.

Common adverse effects include infusion-related reactions, neutropenia, thrombocytopenia, anemia, infections, fatigue, diarrhea, nausea, and cough or dyspnea. Serious risks include severe infections and hypersensitivity reactions. Research continues to evaluate additional indications and combination strategies.