Isatuximab (Specialist drug)
Brand names: Sarclisa
Isatuximab is an anti-CD38 monoclonal antibody used as a specialist treatment for multiple myeloma, typically in combination with other anti-myeloma agents. It is given by intravenous infusion under haemato-oncology supervision.
Adult dose
Dose adjustments
No dose adjustment of isatuximab is needed in patients with mild, moderate, severe or end-stage renal impairment.
Dose independently re-sourced from UK Summary of Product Characteristics (SPC) via the eMC; US FDA prescribing information (openFDA / DailyMed) — cross-check; US labelling may differ from UK — clinician-reviewed. Always confirm against the product SmPC and your local formulary before prescribing.
Contraindications
- Hypersensitivity to the active substance or to any of the excipients (US label: severe hypersensitivity to isatuximab or any of its excipients)
Side effects
- Infusion-related / systemic administration reactions (27.5% across formulations; 3.1% with the subcutaneous formulation, mainly pyrexia, dyspnoea and sinus tachycardia)
- Diarrhoea (27.2%)
- Neutropenia (25.1%; 51% in the pomalidomide-dexamethasone pooled dataset, grade >=3 in 50.7%)
- Upper respiratory tract infection (23%) and bronchitis
- Pneumonia (22%) - the most frequent serious adverse reaction (16.5%) and the commonest fatal one (1.9%)
- Fatigue (20.7%); injection site reactions (11.9% of patients, all grade <=2); thrombocytopenia; second primary malignancies
Interactions
- Interference with serological testing - as an anti-CD38 antibody, isatuximab causes false-positive indirect antiglobulin (indirect Coombs) tests, antibody screening and identification panels and antihuman globulin crossmatches; type and screen patients before starting treatment and inform the blood bank (US label section 7.1; UK SPC 4.5 not captured in source bundle)
- Interference with serum protein electrophoresis and immunofixation assays used to monitor M-protein, which may affect determination of complete response; a specific interference-mitigating assay may be needed (US label section 7.1)
- Combination with pomalidomide or lenalidomide is contraindicated in pregnancy - refer to those products' prescribing information and REMS/Pregnancy Prevention Programme requirements (US label section 8.1)
Clinical monograph
How it works
It binds CD38 on myeloma cells and triggers tumour cell death through antibody-dependent cellular cytotoxicity, complement-dependent cytotoxicity, phagocytosis and direct pro-apoptotic effects.
Prescribing in practice
- Infusion-related reactions are common, particularly with the first infusion, so premedication and close monitoring during administration are essential.
- Anti-CD38 antibodies interfere with blood compatibility testing, so baseline blood typing and screening should be arranged before starting.
- Neutropenia and increased infection risk occur, and antiviral prophylaxis against herpes zoster is generally advised.
Monitoring
Monitor full blood count and for infusion reactions and infection during treatment.
Counselling the patient
- Infusion reactions are most likely with the first dose; report flushing, breathlessness or chills to staff straight away.
- Carry information that you are receiving an anti-CD38 antibody, as it can affect blood crossmatch results for some time.
- Report fever or signs of infection promptly.
Evidence & guidelines
The ICARIA-MM and IKEMA trials demonstrated benefit of isatuximab-based combinations in relapsed or refractory multiple myeloma.
Reference: NICE TA658; SmPC; Drug verified in RxNorm (NLM); confirm dosing against the manufacturer SPC (eMC). Verify against your local formulary and current prescribing references before prescribing. The structured dose values shown have been reviewed by a clinician. Monograph status: clinician-reviewed (2026-07-04).
Related
Curated clinical cross-links plus same-class fallbacks.
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