FDA Approves Subcutaneous Isatuximab-irfc for Multiple Myeloma

The US Food and Drug Administration (FDA) has announced the approval of isatuximab-irfc (Sarclisa Escena; Sanofi-Aventis U.S. LLC) for subcutaneous (SC) injection across several multiple myeloma (MM) indications.

This approval provides oncology nurses and their patients with a new, potentially more convenient delivery method for a treatment that has traditionally required intravenous (IV) administration.

The FDA has authorized isatuximab-irfc for three specific adult patient populations:

• In combination with pomalidomide (Pomalyst) and dexamethasone (Pd) for patients who have received at least one prior line of therapy, including lenalidomide (Revlimid) and a proteasome inhibitor.
• In combination with carfilzomib (Kyprolis) and dexamethasone (Kd) for patients with relapsed or refractory multiple myeloma who have received one to three prior lines of therapy.
• In combination with bortezomib (Velcade), lenalidomide, and dexamethasone (VRd) for patients with newly diagnosed multiple myeloma who are not candidates for an autologous stem cell transplant.

Clinical trial evidence supporting subcutaneous administration

The approval of the subcutaneous formulation was heavily supported by the IRAKLIA (NCT05405166) trial, an open-label, non-inferiority study. This trial randomized 531 patients to receive either isatuximab-irfc via SC injection using an on-body delivery system (OBDS) or the standard IV formulation, both in combination with Pd.

The results demonstrated that the SC delivery was non-inferior to IV administration. Specifically, the overall response rate (ORR) was 71.1% in the SC cohort compared to 70.5% in the IV cohort. Furthermore, pharmacokinetic data showed that the geometric mean ratio for observed steady-state trough concentrations (Ctrough) was 1.53, confirming that the SC route maintains effective therapeutic levels.

Additional support came from the IZALCO (NCT05704049) trial, a phase 2 study involving 74 patients with relapsed and/or refractory multiple myeloma treated with SC isatuximab-irfc in combination with Kd. This study reported an ORR of 79.7%.

For newly diagnosed patients, the IsaSocut (NCT05889221) trial evaluated the SC formulation in combination with VRd. In this single-arm phase 2 study of 74 transplant-ineligible patients, the ORR reached a remarkable 97.3%.

Nursing considerations: administration and dosage

For oncology nurses, the shift to subcutaneous administration involves new delivery technologies. The recommended dose of isatuximab-irfc is 1,400 mg. This dose is administered as a single SC injection using either the CirCLIQ OBDS or a manual syringe and infusion set.

The inclusion of an on-body delivery system is a significant development in the oncology outpatient setting, potentially reducing the time patients spend in the infusion chair. The FDA’s review of this application was also facilitated by the Assessment Aid, a voluntary submission from the manufacturer designed to streamline the regulatory process.

Safety and monitoring

Despite the change in the route of administration, the safety profile of isatuximab-irfc remains a critical focus for nursing surveillance.

The prescribing information for Sarclisa Escena includes several warnings and precautions that nurses must monitor:

• Administration reactions: Both hypersensitivity and other reactions related to the SC injection.
• Hematologic toxicity: Neutropenia is a known risk, requiring regular monitoring of complete blood counts.
• Infection risk: Patients should be monitored for signs of infection during treatment.
• Secondary malignancies: There is a precaution regarding the development of second primary malignancies.
• Laboratory interference: Isatuximab-irfc can interfere with certain laboratory tests, such as cross-matching for blood transfusions or serum protein electrophoresis.
• Embryo-fetal toxicity: Healthcare providers should advise patients of potential risks to a fetus.

Isatuximab-irfc previously received orphan drug designation, highlighting its role in treating a relatively rare disease like multiple myeloma. Healthcare professionals are encouraged to report any serious adverse events to the FDA’s MedWatch Reporting System to continue building the safety profile of this SC formulation.

Impact on patient care

The transition from IV to SC administration represents a continuing trend in oncology aimed at improving the patient experience and clinical efficiency. By offering a fixed 1,400 mg dose via an on-body delivery system, the treatment process may become less invasive for patients who often face a heavy burden of frequent clinic visits. As frontline providers, oncology nurses will play a vital role in educating patients on the use of the OBDS and monitoring for any unique reactions associated with this new delivery method.

FDA approves isatuximab-irfc for subcutaneous injection for multiple myeloma indications. U.S. Food and Drug Administration. Updated July 10, 2026. Accessed July 10, 2026. https://www.fda.gov/drugs/resources-information-approved-drugs/fda-approves-isatuximab-irfc-subcutaneous-injection-multiple-myeloma-indications