Gazyvaro (Obinutuzumab) — NZ Medication Guide | KiwiMeds
✅ Reviewed by Ramon Wong, BPharm, Registered Pharmacist (New Zealand) | May 2026 — This information is for educational purposes only and is not a substitute for personalised advice from your doctor or pharmacist. Always seek professional guidance before making changes to your medications.
What is Gazyvaro (obinutuzumab)?
Gazyvaro (generic name: obinutuzumab) is an intravenous (IV) cancer medicine — a type of monoclonal antibody — used to treat chronic lymphocytic leukaemia (CLL). It targets the CD20 protein found on the surface of cancerous B-cells, marking them for destruction by the immune system. Obinutuzumab is given as an infusion at a hospital or cancer treatment centre.
What is it used for? (NZ context)
In New Zealand, obinutuzumab (Gazyvaro) is funded by Pharmac for adults with chronic lymphocytic leukaemia (CLL).
From 1 May 2026, Pharmac funds obinutuzumab + venetoclax as a first-line (initial) combination treatment for CLL. This gives NZ patients with CLL another funded option alongside the ibrutinib + venetoclax combination. Clinical evidence shows that the combination of obinutuzumab and venetoclax can help people achieve longer periods without CLL progression, often avoiding traditional chemotherapy.
See the Pharmac announcement for full eligibility criteria. Your haematologist or oncologist will advise on which combination treatment is best suited to you.
How does it work?
Obinutuzumab is a monoclonal antibody — a type of protein engineered to recognise and attach to a specific target. It targets CD20, a protein found on the surface of B-cells, including the cancerous B-cells in CLL. When obinutuzumab binds to CD20, it triggers the immune system to attack and destroy those cells. Obinutuzumab is a “third-generation” anti-CD20 antibody, designed to be more effective than earlier versions (like rituximab) at triggering immune-mediated cancer cell death. By combining obinutuzumab with venetoclax (which directly triggers cancer cell death through a different mechanism), the two medicines attack CLL from complementary angles.
How to take it
Obinutuzumab (Gazyvaro) is given as an intravenous (IV) infusion at a hospital or cancer treatment centre — it cannot be taken at home. It is given in treatment cycles, typically:
- Cycle 1: Three infusions over the first month (Day 1, Day 8, Day 15). The first infusion is split over two days to reduce reaction risk.
- Cycles 2–6: One infusion per cycle (every 28 days)
Common side effects
Common side effects of obinutuzumab include:
- Infusion-related reactions — the most common issue, especially with the first infusion: chills, fever, flushing, nausea, low blood pressure, or breathing difficulty during the drip
- Low white blood cell counts (neutropenia) — increased infection risk
- Low platelet counts (increased bleeding/bruising)
- Fatigue
- Nausea
- Diarrhoea
- Constipation
- Cough
- Muscle and joint aches
Serious side effects to watch for
Contact your treatment team or go to hospital urgently if you experience:
- Severe infusion reaction during or shortly after the drip — difficulty breathing, chest tightness, swelling of the face or throat, feeling faint
- Fever or signs of serious infection — your white blood cells will be low and infections can become serious quickly
- Progressive Multifocal Leukoencephalopathy (PML) — a rare but very serious brain infection caused by JC virus in severely immunosuppressed patients. Symptoms: new confusion, weakness, vision changes, balance problems
- Hepatitis B reactivation — if you have ever had hepatitis B, obinutuzumab can reactivate it. Tell your doctor your full medical history before starting
- Unusual bruising or bleeding
- Tumour lysis syndrome — especially when starting in combination with venetoclax
Important drug interactions
Obinutuzumab can interact with:
- Live vaccines — not recommended during or immediately after obinutuzumab treatment; discuss timing of any vaccines with your specialist
- Other immunosuppressants — increased infection risk
- Blood thinners — increased bleeding risk when combined with anticoagulants or antiplatelet medicines
Things to avoid while taking it
- Live vaccines — not safe during treatment or for several months after
- Contact with people who are sick or have active infections — your immune system is significantly weakened
- NSAIDs (ibuprofen, naproxen) and blood thinners without specialist advice — increased bleeding risk when platelet counts are low
NZ-specific information
Brand name in NZ: Gazyvaro
Funded: Yes — from 1 May 2026 in combination with venetoclax as first-line CLL treatment
How it is given: IV infusion at hospital (not a take-home medicine)
Special Authority: Required — your haematologist will apply
Prescription type: Hospital specialist prescription
Obinutuzumab + venetoclax is one of two funded combination options for CLL in NZ (the other being ibrutinib + venetoclax). Unlike ibrutinib + venetoclax (both oral), obinutuzumab requires IV infusions at a treatment centre. Your haematologist will discuss which combination is most appropriate for your situation.
Frequently asked questions
Will I need to be in hospital for obinutuzumab?
Yes — obinutuzumab is given as an IV infusion and must be administered in a hospital or oncology day unit. You will not need to stay overnight unless you have a reaction or other complication.
How many infusions will I need?
Usually 6 cycles total, with three infusions in the first cycle and one infusion per cycle after that — approximately 6 infusions over 6 months, though your schedule may vary.
Can I work while on this treatment?
Many people continue to work, though infusion days will require time off. Fatigue can be significant; discuss your circumstances with your treatment team.
Do I need to get tested for hepatitis B before starting?
Yes — your haematologist will check your hepatitis B status before starting obinutuzumab, as the medicine can reactivate hepatitis B in people who have been previously infected.
Related medications
- Venetoclax (Venclexta) — given in combination with obinutuzumab for CLL
- Ibrutinib (Imbruvica) — the other CLL combination option (ibrutinib + venetoclax)