Rituximab: Uses, Cost and Side Effects

Cancers whose cells carry the CD20 marker on their surface. In practice that means B-cell non-Hodgkin lymphoma — including diffuse large B-cell and follicular lymphoma — and chronic lymphocytic leukaemia. It is not used for solid tumours such as breast, lung or colorectal cancer. Outside oncology it also treats several autoimmune diseases.

Rituximab is a monoclonal antibody built to find one thing: a protein called CD20 that sits on the surface of B lymphocytes. It attaches there and flags those cells for destruction by the patient’s own immune system. That makes it an immunotherapy, in the literal sense — it works through immune mechanisms rather than by poisoning dividing cells. It is simply a much older kind than the checkpoint inhibitors that the word now brings to mind. Approved in 1997, it was the first therapeutic antibody licensed anywhere for cancer, and most people who receive it are never told it belongs to the same family.

It is long approved by the CDSCO and widely marketed in India. India was, in fact, the first country in the world to launch a rituximab biosimilar, in 2007, and as of August 2026 several CDSCO-approved Indian versions are sold alongside the originator brand.

Adding rituximab to chemotherapy became the standard approach in CD20-positive B-cell lymphoma because randomised trials showed better disease control than chemotherapy alone, and NCCN and ESMO lymphoma guidelines build their regimens around it. What that does not mean is that every lymphoma calls for it. The deciding fact is whether the biopsy report says CD20 is present, not the word on the diagnosis line.

As a slow drip into a vein, in a day-care unit — never as a tablet. The usual lymphoma dose is 375 mg per square metre of body surface area, given on day one of each chemotherapy cycle. The first infusion is deliberately slow and often takes four to six hours. Later ones run faster.

The sequence is the same almost everywhere, and knowing it in advance removes most of the anxiety of the first day.

1. Before the first dose. Blood counts, liver and kidney tests, and hepatitis B screening. The hepatitis B test is not optional — see the monitoring section below.
2. Premedication, 30–60 minutes ahead. Paracetamol and an antihistamine, usually with a corticosteroid. This is what keeps most first-infusion reactions mild.
3. The drip starts slowly. Product labelling suggests around 50 mg per hour for the first dose, stepped up every 30 minutes if nothing happens, to a ceiling of 400 mg per hour.
4. Observation all the way through. Blood pressure, pulse and temperature are checked at each step-up. A reaction usually shows itself at exactly these moments.
5. Later cycles are quicker. They typically start at 100 mg per hour and take three to four hours; some units use a shorter schedule of around 90 minutes for patients who tolerated the earlier doses well.
6. Home the same day. Rituximab is a day-care infusion. Admission is needed only if something else in the regimen calls for it.

A subcutaneous form exists for some lymphoma indications and takes minutes rather than hours, but it is only used after at least one full intravenous dose has been given and tolerated. Whether it is stocked, and whether it is approved for the specific indication, varies by brand and by centre — a fair question for the treating team rather than an assumption.

How many doses depends entirely on the regimen. A first-line lymphoma course commonly runs six to eight cycles at three-week intervals. Follicular lymphoma maintenance, where it is used, can continue every two to three months for up to two years, which is why the per-cycle cost matters more than the per-vial price.

Symptoms that appear while the drip is running, most often during the very first dose. Fever, chills, shivering, itching, a rash, a tight throat, a cough, a drop in blood pressure. Product labelling reports that a majority of patients have some reaction on the first infusion. Most are mild and settle once the drip is slowed or paused.

Tell the nurse in the chair the moment anything changes. Do not wait to see whether it passes. Breathlessness, chest tightness, throat swelling or feeling faint during an infusion are treated as emergencies, and the unit is set up for precisely that. Slowing or stopping the drip is a routine step, not a failure — most patients who react on the first infusion complete the same infusion at a lower rate on the same day.

Once home, a temperature of 38 °C or more, new breathlessness or a spreading rash means going to the emergency department the same day rather than waiting for the next appointment. Take the day-care record with you: the brand, the batch number and the date of the last dose are the three things the receiving doctor will want.

Reactions become markedly less frequent from the second cycle onwards. Patients who had a difficult first infusion often assume every cycle will be the same. Usually it is not.

Most cancer patients, including most people reading about immunotherapy. Rituximab acts only where CD20 is present. If the biopsy does not show CD20, the antibody has nothing to attach to, and neither price nor availability makes it an option.

Concretely, it is not a treatment for solid tumours — breast, lung, colorectal, prostate, head and neck, cervical or ovarian cancer. It is not used in Hodgkin lymphoma, in myeloma, or in T-cell lymphoma, because those cells do not usually carry the target. And it is not an alternative to a checkpoint inhibitor: the two work by entirely different mechanisms, in entirely different diseases, whatever the price difference between them.

Even within CD20-positive disease it is not for everyone. It is not given during an active severe infection, or to anyone who has had a severe reaction to it before. Everyone being considered for it needs hepatitis B screening first, because the medicine can reactivate a dormant hepatitis B infection — a boxed warning in the labelling, not a rare technicality. Existing heart or lung disease is weighed carefully, since a significant infusion reaction places real strain on both. Live vaccines are avoided during and after treatment. Pregnancy and contraception need an explicit conversation before the first cycle, not after it.

Two rare but recognised risks belong in the same conversation: progressive multifocal leukoencephalopathy, a serious brain infection, and severe mucocutaneous reactions. Both are uncommon. Both are reasons the treating team monitors rather than reasons the medicine is withheld from people who need it.

Asking whether an approved biosimilar exists for a medicine already prescribed is a different and entirely reasonable question — that is a conversation about brand within the same molecule. Asking to be switched to a cheaper molecule that the diagnosis does not call for is not.

Indicatively ₹15,000 to ₹45,000 for a 500 mg vial as of August 2026, depending on whether it is the originator brand or an approved Indian biosimilar. One dose for an average-sized adult needs more than one vial. Rituximab is among the cheaper antibody medicines sold here, because biosimilar competition for it goes back to 2007.

The drug is one line of the bill and not the whole of it. Day-care charges, nursing and infusion time, the premedication, the chemotherapy drugs given alongside it, pre-cycle blood tests and response-assessment imaging are all billed separately, and none of them change with the brand of rituximab used. That is why two hospitals can quote different totals while using the same product. An itemised quote — drug, day care, monitoring, supportive care — makes the comparison meaningful in a way a single bundled figure never does.

On schemes and insurance: government scheme ceilings such as Aarogyasri are set against a protocol rather than against a brand, so a costlier brand does not automatically stretch the package. Insurance sub-limits for injectable oncology drugs differ policy to policy, and some reimburse against a named brand rather than the molecule. Confirm the applicable ceiling in writing before the first cycle rather than after it. Rituximab Biosimilars in India traces how this molecule’s price actually moved over nineteen years, which is the honest reference point for what biosimilar competition does and how long it takes.

Mainly infection risk, because the medicine clears normal B cells along with the abnormal ones. Antibody levels can stay low for months after treatment ends. Hepatitis B can reactivate. Neutrophil counts can fall weeks after a dose. None of this argues against the drug — it is the reason for the monitoring schedule around it.

• Hepatitis B reactivation. Screening for HBsAg and anti-HBc before the first dose is a labelled requirement and is recommended in NCCN and ASCO guidance. A past, cleared infection can still reactivate, which is why both tests are done. Antiviral prophylaxis follows where indicated.
• Low immunoglobulins and repeat infections. Antibody levels can remain low for months after the last dose. A minority of patients need immunoglobulin replacement.
• Delayed neutropenia. The neutrophil count can drop weeks to months after a dose, long after the infusion is forgotten. Any fever needs an urgent blood count, not a wait.
• Vaccination timing. Live vaccines are avoided during and for a period after treatment, and the response to any vaccine may be poor for months. Where there is time, vaccination is completed before starting.
• Progressive multifocal leukoencephalopathy. Rare, but serious. New confusion, limb weakness, or changes in vision or speech need urgent review rather than a routine appointment.
• Heart and lung disease. Pre-existing disease is taken into account before the first infusion, because a significant reaction places strain on both.

One thing genuinely separates rituximab from the newer immunotherapy drugs: its long-term safety record is mature. It has been in continuous use since the late 1990s, so what happens years afterwards has been observed rather than estimated. For checkpoint inhibitors and for cell therapies, that same long-horizon evidence is still being gathered, and anyone who tells you otherwise is ahead of the data.

Same idea, different target. Every antibody medicine finds one marker and acts on it. Rituximab finds CD20 on B cells. Trastuzumab finds HER2. Cetuximab and nimotuzumab find EGFR. Which one applies, if any, is decided by what the biopsy shows — never by which medicine sounds most advanced.

The HER2 story is the closest parallel to rituximab’s, and it has since moved further with antibody-drug conjugates that carry chemotherapy directly to the target cell — Trastuzumab and Trastuzumab Deruxtecan in Breast Cancer covers where that has reached. In head and neck cancer the EGFR antibodies work the same way against a different marker, and India has a domestically developed option there as well, compared in Cetuximab and Nimotuzumab in Head and Neck Cancer.

For a full picture of which of these molecules are actually approved and marketed in India as of August 2026 — several discussed internationally are not — Which Antibody Medicines Are Available in India? sets out the current position molecule by molecule.

• Which Antibody Medicines Are Available in India? — the molecule-by-molecule position as of August 2026.
• Trastuzumab and Trastuzumab Deruxtecan in Breast Cancer — the HER2 antibody and what came after it.
• Cetuximab and Nimotuzumab in Head and Neck Cancer — the two EGFR antibodies used in India, compared.
• Rituximab Biosimilars in India — nineteen years of price movement on this exact molecule.
• Immunotherapy Medicines Explained — the index of antibodies, checkpoint inhibitors and biosimilars.
• Immunotherapy at a glance — what this family of treatments does, and what it does not.

Editorial information about a prescription-only medicine — not an offer, a price list, or a recommendation to use any named product, and no comparative quality claim between manufacturers. Clinical statements follow product labelling and published NCCN, ASCO and ESMO patient-education guidance; all pricing and regulatory statements are indicative and dated to August 2026. Whether rituximab applies to a particular patient, in which regimen and in which brand, is a decision for the treating oncologist.