Rituximab (MabThera / Rituxan)
Anti-CD20 monoclonal antibody for CD20-positive B-cell lymphoma and CLL.
What is Rituximab?
What it targets
Rituximab binds to CD20, a surface antigen on B cells. Blocking CD20 triggers immune-mediated killing of CD20-positive cancer cells.
Who it may help
Patients with CD20-positive B-cell NHL, DLBCL, follicular lymphoma, CLL, or other CD20-positive B-cell malignancies confirmed by biopsy.
Why testing matters
Rituximab only works in CD20-positive disease. IHC or flow cytometry must confirm CD20 expression before treatment can begin.
Which cancers can Rituximab treat?
Rituximab is approved for several CD20-positive B-cell cancers where pathology has confirmed CD20 expression.
| Diffuse large B-cell lymphoma (DLBCL) | FDA and EMA approved in combination with CHOP-like chemotherapy for previously untreated CD20-positive DLBCL. R-CHOP substantially improved outcomes compared to CHOP alone and remains a global standard regimen. |
| Follicular lymphoma | Approved for first-line and relapsed/refractory settings, alone or with chemotherapy. Also approved as maintenance therapy after response to induction, extending remission duration in eligible patients. |
| Marginal zone and indolent B-cell NHL | Used in selected CD20-positive cases such as marginal zone lymphoma and small lymphocytic lymphoma where treatment is clinically indicated. |
| Chronic lymphocytic leukemia (CLL) | Approved in combination with fludarabine and cyclophosphamide (R-FC) for CD20-positive CLL. Newer regimens using venetoclax or BTK inhibitors may be preferred based on risk profile and TP53 status. |
| Mantle cell lymphoma (MCL) | Used as part of chemoimmunotherapy regimens and maintenance strategies in selected patients with MCL, typically as part of intensive or alternating regimens. |
| Pediatric mature B-cell NHL | Rituximab-containing regimens are approved in selected pediatric settings for mature B-cell NHL and B-cell acute leukemia in combination with chemotherapy. |
Are you eligible for Rituximab?
Eligibility depends on confirmed CD20 expression, cancer type, organ function, infection status, and overall health.
- CD20-positive cancer confirmed by immunohistochemistry (IHC) or flow cytometry
- Diagnosis of B-cell NHL, DLBCL, follicular lymphoma, CLL, or a related B-cell malignancy
- Hepatitis B surface antigen negative, or antiviral prophylaxis arranged if HBsAg-positive
- No active serious uncontrolled infection
- Adequate blood counts (CBC) to tolerate planned treatment
- Adequate liver and kidney function for the planned regimen
- No prior history of severe infusion reaction to rituximab or other monoclonal antibodies
- Pregnancy excluded or benefit-risk assessment completed with oncologist
How does Rituximab work?
- Binding to CD20 on B cells
- Activating immune killing pathways
- Direct apoptosis signaling
- Sustained depletion of CD20-positive B cells
Rituximab was among the first monoclonal antibodies approved to treat cancer. R-CHOP has remained a global standard regimen for DLBCL for over 25 years.
Tests required before starting Rituximab
These tests confirm eligibility, identify safety risks, establish baselines, and guide monitoring during treatment.
| CD20 expression (IHC or flow cytometry) | Essential eligibility test. CD20 must be confirmed positive on the cancer cells before rituximab can be used. |
| Biopsy and histopathology | Confirms lymphoma subtype — DLBCL, follicular lymphoma, MCL, marginal zone, or CLL/SLL. Determines the exact treatment regimen. |
| Hepatitis B surface antigen and core antibody | Mandatory before rituximab. HBsAg-positive patients need antiviral prophylaxis before starting. Core antibody-positive patients need monitoring or prophylaxis as directed by oncologist. |
| Complete Blood Count (CBC) | Baseline blood counts before treatment. Repeated throughout therapy to monitor cytopenias and guide cycle decisions. |
| LDH and uric acid | Elevated levels indicate high tumour burden and greater risk of tumour lysis syndrome after the first infusion. |
| Liver and kidney function tests | Required to assess organ function and safety for the planned combination regimen. |
| CT or PET-CT scan | Staging scans define disease extent and provide a baseline for response assessment after treatment. |
| Hepatitis C and HIV testing | Performed when clinically appropriate, as immune suppression from rituximab can affect patients with these infections. |
How is Rituximab given?
Rituximab is given as an intravenous infusion in a hospital or dedicated infusion centre, always with premedication and nursing supervision.
| Dose — NHL settings | Typically 375 mg/m² body surface area per cycle. Exact dose is calculated by the oncologist based on individual weight and height. |
| Dose — CLL settings | Often 500 mg/m² from cycle 2 onwards in R-FC combination regimens. Oncologist determines exact dose and schedule. |
| Premedication | Paracetamol, antihistamine, and sometimes a corticosteroid are given 30 to 60 minutes before each infusion to reduce infusion reaction risk. |
| First infusion rate | Started at 50 mg/hr and increased gradually if tolerated. First infusion may take 4 to 6 hours due to the higher risk of reactions at first exposure. |
| Subsequent infusions | Can be given faster if earlier infusions were well tolerated. Some centres use a 90-minute accelerated protocol from cycle 2 onwards. |
| Frequency and cycles | Typically given once per cycle, every 3 weeks in R-CHOP. Maintenance rituximab for follicular lymphoma is given every 2 months for up to 2 years. |
| Monitoring during infusion | Blood pressure, heart rate, and oxygen saturation are monitored throughout. Infusion slowed or paused if a reaction occurs. |
| Duration of therapy | Determined by disease type and response. Induction typically involves 6 to 8 cycles. Maintenance continues for up to 2 years in eligible patients. |
Clinical evidence and benefits of Rituximab
Rituximab has decades of clinical evidence supporting its use across multiple B-cell cancers.
| R-CHOP in DLBCL | Adding rituximab to CHOP chemotherapy substantially improved overall survival and event-free survival in CD20-positive DLBCL, establishing R-CHOP as the global standard of care. |
| Follicular lymphoma — induction and maintenance | Rituximab combined with chemotherapy significantly improved progression-free survival. Maintenance rituximab after response extended remission duration in multiple large trials. |
| CLL combination benefit | Rituximab combined with fludarabine and cyclophosphamide improved outcomes in selected CD20-positive CLL patients compared to chemotherapy alone in fit patients without high-risk features. |
| Established long-term safety profile | Rituximab has been in clinical use since 1997. The long-term safety and efficacy data are well characterised and referenced in all major international guidelines. |
| Biosimilar access | Multiple approved biosimilars in India, China, the USA, and Europe have expanded access and substantially reduced cost, making rituximab-based treatment more available globally. |
Clinical outcomes vary by disease subtype, stage, combination regimen, and individual patient factors. These represent published clinical evidence, not guaranteed results.
Side effects of Rituximab
Rituximab is a targeted therapy and generally better tolerated than cytotoxic chemotherapy, though infusion reactions, immune suppression, and serious safety risks require careful monitoring.
| Infusion reactions | Fever, chills, rigors, flushing, or low blood pressure during infusion — most common with the first dose. Premedication significantly reduces the risk. |
| Fatigue | Common throughout the treatment course. Usually manageable with rest and activity pacing. |
| Nausea | Mild to moderate, often infusion-related. Anti-nausea medication can be given if needed. |
| Headache | May occur during or after infusion. Usually mild and resolves without specific treatment. |
| Low blood counts (cytopenias) | Neutropenia, thrombocytopenia, and anaemia may occur, particularly when combined with chemotherapy. Regular CBC monitoring is essential before each cycle. |
| Increased infection risk | B-cell depletion reduces the immune response to infection. Bacterial and viral infections are more likely, especially with repeated or maintenance courses. |
| Rash and itching | Skin reactions may occur during or after infusion. Usually mild and manageable with antihistamines. |
| Low blood pressure during infusion | Hypotension during infusion is common with early cycles. Antihypertensive medicines may need to be temporarily withheld on infusion days. |
| Respiratory symptoms | Cough, throat irritation, or breathing changes may occur during infusion and are monitored by nursing staff. |
| Low immunoglobulin levels | Rituximab depletes normal B cells, reducing immunoglobulin production over time. Low IgG levels may require monitoring or immunoglobulin replacement therapy. |
Contact your doctor immediately if you develop:
- Breathing difficulty, wheezing, or chest tightness during or after infusion
- High fever, chills, or signs of serious infection
- Yellow skin or eyes, dark urine — possible hepatitis B reactivation
- New neurological symptoms — confusion, vision changes, speech problems, or weakness
- Severe skin blistering, peeling, or ulceration
- Chest pain, palpitations, or irregular heartbeat
- Severe abdominal pain or bruising not explained by injury
Safety precautions and drug interactions
Tell your oncologist and pharmacist about all medicines, supplements, herbal products, and recent vaccinations before starting rituximab.
- Hepatitis B status must be confirmed before treatment — HBsAg-positive patients require antiviral prophylaxis
- HBcAb-positive patients need enhanced monitoring or antiviral prophylaxis as directed by oncologist
- Live attenuated vaccines must not be given during rituximab or for several months after the last dose
- Inactivated vaccines such as influenza and pneumococcal should ideally be given before starting treatment
- Antihypertensive medicines may need to be withheld on infusion days due to hypotension risk
- Rituximab is not recommended during pregnancy — effective contraception required for 12 months after last dose
- Breastfeeding should be avoided during treatment and for 6 months after the last rituximab dose
- Prior severe infusion reaction to rituximab or other monoclonal antibodies requires specialist review before re-treatment
Rituximab combination treatments
Rituximab is most commonly combined with chemotherapy or other targeted agents depending on the specific lymphoma subtype and treatment goal.
| R-CHOP (DLBCL and aggressive NHL) | Rituximab combined with cyclophosphamide, doxorubicin, vincristine, and prednisone. Standard of care for CD20-positive DLBCL and aggressive B-cell lymphomas. |
| R-CVP (indolent lymphoma) | Rituximab with cyclophosphamide, vincristine, and prednisolone for patients with indolent B-cell lymphoma who cannot tolerate anthracycline-based regimens. |
| BR (bendamustine-rituximab) | Used in indolent B-cell NHL, mantle cell lymphoma, and selected CLL patients. Associated with good response rates and tolerability in older patients. |
| R-FC (CLL) | Rituximab combined with fludarabine and cyclophosphamide for selected fit CD20-positive CLL patients without del(17p) or TP53 mutation. |
| Maintenance rituximab | Single-agent rituximab every 2 months for up to 2 years after response to induction therapy in follicular lymphoma. Significantly extends remission duration. |
| Sequencing with newer agents | Rituximab may precede or follow BTK inhibitors, venetoclax, CAR-T therapy, or bispecific antibodies depending on disease status and treatment history. |
If Rituximab stops working
Some lymphomas become less sensitive to rituximab over time. Understanding the mechanism guides the choice of next treatment.
| Loss of CD20 expression | CD20 can be downregulated or lost on lymphoma cells after repeated rituximab exposure, reducing the drug's ability to bind and activate killing mechanisms. |
| Complement and immune evasion | Upregulation of complement regulatory proteins on cancer cells can reduce complement-dependent cytotoxicity. Changes in the tumour microenvironment may also limit ADCC. |
| Switching to obinutuzumab | A type II anti-CD20 antibody with different binding and stronger ADCC. Approved in CLL and follicular lymphoma for patients with prior rituximab exposure in certain settings. |
| Bispecific antibodies | Agents such as mosunetuzumab and epcoritamab target both CD20 and CD3, engaging T cells to kill CD20-positive cells regardless of complement availability. |
| CAR-T cell therapy | CD19-directed CAR-T therapy is approved for relapsed or refractory DLBCL and follicular lymphoma after two or more prior lines including rituximab. |
| Clinical trials | Patients with rituximab-refractory lymphoma may be eligible for trials involving novel combinations, bispecifics, antibody-drug conjugates, or next-generation cell therapies. |
Cost of Rituximab by country
Biosimilar rituximab has significantly reduced treatment costs in many countries since originator patent expiry.
| India | Biosimilar Reditux by Dr. Reddy's has been available in India since 2007, substantially reducing cost. Multiple manufacturers supply the Indian market. Patient access programmes are available at major cancer hospitals for eligible patients. |
| China | Multiple NMPA-approved domestic biosimilars are available at significantly lower cost than originator brands. Rituximab is included on national reimbursement drug lists for approved lymphoma indications. |
| USA | Branded Rituxan remains high in cost; biosimilars Truxima, Ruxience, and Riabni are approved. Insurance coverage widely available. Genentech patient assistance programmes exist for uninsured patients. |
| UK / Europe | MabThera and EMA-approved biosimilars covered under NHS and most European national health insurance systems for approved NHL and CLL indications. |
| Southeast Asia / MENA | Availability and cost vary by country. Biosimilars accessible in Thailand, Malaysia, and Turkey. CancerFax can assist with cost and access verification for patients in this region. |
Availability of Rituximab globally
Rituximab is one of the most widely available cancer medicines globally, with originator and biosimilar options across major markets.
India
Rituximab biosimilars including Reditux (Dr. Reddy's) available since 2007. Multiple Indian manufacturers supply the market, making India one of the most accessible countries for affordable rituximab.
China
NMPA has approved domestic biosimilars including HLX01. Widely used in major cancer centres and covered under national health insurance for lymphoma indications in China.
USA
Rituxan (originator) plus biosimilars Truxima, Ruxience, and Riabni are FDA-approved. Available through oncology clinics and specialty pharmacies with insurance or patient assistance programmes.
UK / Europe
MabThera and multiple EMA-approved biosimilars available across Europe. NHS and EU national insurance systems cover rituximab for approved B-cell cancer indications.
Southeast Asia
Available in Thailand, Malaysia, Singapore, Indonesia, and the Philippines through major oncology hospitals. Biosimilar access varies by market and hospital formulary.
Rituximab in current clinical trials
Ongoing research explores rituximab in new combinations, sequencing strategies, and next-generation regimens for B-cell cancers.
| Novel combinations in DLBCL | Trials evaluating rituximab-based regimens with polatuzumab vedotin, lenalidomide, and checkpoint inhibitors to improve on R-CHOP outcomes in high-risk DLBCL. |
| Follicular lymphoma — maintenance optimisation | Studies refining maintenance rituximab duration and patient selection to balance extended remission against cumulative immune suppression. |
| Sequencing with CAR-T and bispecifics | Research examining optimal sequencing — when to use rituximab-based therapy versus CAR-T or bispecific antibodies in relapsed/refractory B-cell lymphoma. |
| Biosimilar real-world evidence | Ongoing pharmacovigilance and real-world data collection on biosimilar rituximab to confirm long-term safety and efficacy equivalence across global markets. |
| Paediatric and older patient studies | Studies optimising rituximab dosing, frequency, and combination strategies in paediatric B-cell NHL and older patients with comorbidities. |
Your treatment journey with Rituximab
Diagnosis and lymphoma subtyping
CD20 testing and staging
Hepatitis B screening and clearance
Treatment planning and first consultation
First infusion with close monitoring
Ongoing cycles and blood test monitoring
Response assessment
Maintenance or post-treatment monitoring
Questions to ask your oncologist about Rituximab
- Is my lymphoma confirmed as CD20-positive and what test showed this?
- Will I receive rituximab alone or combined with chemotherapy?
- How many cycles will I need and how long will treatment last?
- Do I need a hepatitis B test before starting and what happens if I have hepatitis B?
- How long will each infusion take and what happens if I have a reaction?
- What infection precautions should I follow during and after rituximab?
- Is a biosimilar as effective as the originator brand?
- What are my options if rituximab stops working or my lymphoma returns?
How CancerFax supports Rituximab patients
CancerFax helps patients navigate access to rituximab, understand CD20 testing, and connect with lymphoma specialists in India, China, and internationally.
| Medical report review | Upload your biopsy, CD20 IHC, flow cytometry, PET-CT, or blood reports. Our team reviews eligibility for rituximab and explains what the results mean for your treatment options. |
| Specialist connection | We connect patients with haematologists and oncologists experienced in B-cell lymphoma and CLL in India, China, UAE, and international oncology centres. |
| Second opinion | If your response to rituximab is uncertain or you are considering a regimen change, CancerFax arranges specialist second opinions at leading lymphoma centres. |
| Biosimilar and cost guidance | We help patients understand biosimilar options in India and China, compare costs across markets, and navigate patient assistance programmes where available. |
| China treatment access | For patients exploring advanced lymphoma treatment in China — bispecific antibodies, CAR-T therapy, or clinical trials — CancerFax manages hospital coordination, translation, and logistics. |
| Post-rituximab navigation | If lymphoma returns after rituximab, CancerFax helps patients explore next-line options including CAR-T, bispecific antibodies, and international clinical trial access. |
Frequently asked questions about Rituximab
Common questions from patients and caregivers about rituximab treatment
Rituximab is not chemotherapy — it is a monoclonal antibody, a type of targeted therapy. Unlike chemotherapy, which damages cells broadly, rituximab works by binding specifically to the CD20 protein on the surface of B cells and directing the immune system to destroy them. It may be given alone or combined with chemotherapy depending on the cancer type and treatment goal.
The first rituximab infusion typically takes 4 to 6 hours because it is started slowly to monitor for infusion reactions. If the first infusion is well tolerated, later infusions may be given more quickly, often over 90 minutes using an accelerated infusion protocol where available. Your oncologist will decide the rate based on your response.
Rituximab can cause hepatitis B reactivation — a serious and potentially fatal condition where the hepatitis B virus, even in patients who previously had it and cleared it, becomes active again because rituximab depletes B cells that help control the virus. This is one of the boxed warnings in the rituximab prescribing information. Screening before treatment allows your doctor to prescribe antiviral prophylaxis if needed.
Yes. Rituximab depletes normal B cells as well as cancerous ones, which can lead to low immunoglobulin levels and reduced ability to fight infections for months after treatment ends. Some patients may require immunoglobulin replacement if levels fall significantly. Your oncologist will monitor your blood counts and immunoglobulin levels and may recommend infection precautions and vaccination planning.
Rituximab has been used in older patients and those with additional health conditions in clinical practice. The main considerations are infection risk, hepatitis B status, cardiac and kidney function, and performance status. Your oncologist will assess whether the benefit outweighs the risk based on your specific situation. Dose adjustments are not generally made based on age alone, but careful monitoring is essential.
Rituximab is generally not recommended during pregnancy because it crosses the placenta and can cause B-cell depletion in the newborn, increasing the infant's infection risk. Women of childbearing age are advised to use effective contraception during treatment and for 12 months after the last dose. Rituximab should only be used in pregnancy if the treating oncologist determines the benefit clearly outweighs the risk, with specialist guidance.