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Anti-CD20 Monoclonal Antibody — CLL / Follicular Lymphoma

Obinutuzumab

Brand names: Gazyvaro

Obinutuzumab is a humanised anti-CD20 monoclonal antibody used, in combination with chemotherapy, to treat chronic lymphocytic leukaemia and follicular lymphoma.

Dosing — being independently re-sourced

ClinCalc Pro is rebuilding its dose data from primary open sources — the manufacturer SmPC (eMC), the WHO Model Formulary and other official references — under clinician review. This drug's structured dose is not yet published here. Confirm all doses against the product SmPC and your local formulary before prescribing.

Clinical monograph

How it works

This type II glycoengineered anti-CD20 antibody binds CD20 on B cells and induces their depletion through enhanced direct cell death and antibody-dependent cellular cytotoxicity.

Prescribing in practice

  • Infusion-related reactions, which can be severe especially with the first infusion, are a key risk, so premedication and a slow initial infusion rate are required.
  • Hepatitis B reactivation can occur, so screen for hepatitis B before starting and manage according to results.
  • Tumour lysis syndrome and serious infections including a small risk of progressive multifocal leukoencephalopathy can occur.

Monitoring

Monitor the full blood count, for infusion reactions, and for signs of infection or hepatitis B reactivation during and after treatment.

Counselling the patient

  • Medicines are given beforehand to reduce the chance of an infusion reaction.
  • Report fever or signs of infection, and any new neurological symptoms, promptly.

Evidence & guidelines

Obinutuzumab-based regimens are supported by trials such as CLL11 and GALLIUM and by NICE technology appraisals.

Reference: CLL11 Trial (Goede et al. NEJM 2014); GALLIUM Trial (Marcus et al. NEJM 2017); NICE TA343; SPC Gazyvaro; Drug verified in RxNorm (NLM); confirm dosing against the manufacturer SPC (eMC). Verify against your local formulary and current prescribing references before prescribing. Monograph status: clinician-reviewed (2026-07-04).

Related

Curated clinical cross-links plus same-class fallbacks.

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