Daratumumab: Uses, Cost and Side Effects in Myeloma

Patients with multiple myeloma — and, in practice, almost no one else. Daratumumab attaches to CD38, a protein that myeloma plasma cells carry in large amounts. It is used in newly diagnosed myeloma and in relapsed disease, nearly always alongside other myeloma drugs rather than on its own. It has no role in solid tumours.

Daratumumab is a monoclonal antibody built to find one target: CD38. It binds there, flags the cell for destruction by the patient’s own immune system, and also acts on the immune cells around the tumour. That makes it an immunotherapy in the literal sense — it works through immune mechanisms rather than by poisoning dividing cells. Most people given it are told only that they are on “an antibody”, and very few are told it belongs to the same broad family as the checkpoint inhibitors they have read about.

On regulatory status: daratumumab is approved by the CDSCO and marketed in India by Janssen, part of Johnson & Johnson, as Darzalex for the intravenous form and Darzalex Faspro for the subcutaneous form. As of August 2026 there is no CDSCO-approved Indian biosimilar of the molecule — the single biggest difference between this medicine and older antibodies such as rituximab and trastuzumab.

It was added to standard myeloma combinations because randomised trials showed better disease control than the same combinations without it, and NCCN and ESMO myeloma guidelines build several of their recommended regimens around it. What that does not mean is that every patient with a plasma-cell disorder needs it, or needs it now.

Both forms exist, and the difference is not cosmetic. The intravenous form is a drip that commonly runs about seven hours on the first day. The subcutaneous form is a fixed 1,800 mg dose injected into the skin of the abdomen over three to five minutes. Both are marketed in India. The schedule of doses is the same.

This is the change that matters most to families, and the part least often explained before the first cycle. A myeloma course is long, and dosing is weekly at the start. The difference between seven hours in a chair and five minutes plus observation decides whether an attendant loses a working day every week for two months.

What the first day actually looks like is the same in most units, and knowing the sequence in advance removes a good deal of the anxiety.

1. Before the first dose. Blood counts, kidney and liver tests, hepatitis B screening, and a type-and-screen sample for the blood bank. The blood-bank sample is not optional — the reason is explained further down this page.
2. Premedication. A corticosteroid, paracetamol and an antihistamine, usually one to three hours ahead. This is what keeps most first-dose reactions mild.
3. The drip starts slowly, or the injection is given. The intravenous rate is stepped up in stages if nothing happens. The subcutaneous injection goes into the abdominal wall a short distance from the navel.
4. Observation. Blood pressure, pulse and temperature at each step-up, and for a set period afterwards. Reactions declare themselves at exactly these moments.
5. A steroid afterwards. Often continued for a day or two after the first doses, to blunt late reactions.
6. Home the same day. Daratumumab is day-care treatment. Admission is needed only if something else in the regimen calls for it.

Reactions become markedly less frequent from the second dose onwards. Patients who had a difficult first infusion often assume every cycle will be the same. Usually it is not. Infusion Reactions With Antibody Medicines: What to Expect covers what these feel like and how units handle them.

Administration reactions in the first hours, then infection risk over months. The early problem is a reaction while the drug is going in — a blocked nose, cough, throat tightness, chills or wheeze. The longer-running problem is a fall in white cells and a higher risk of infection, including shingles and chest infections.

Timing is the useful thing to know. Nothing on this list appears at random; each has a window in which it is expected, and the unit monitors accordingly.

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: the brand, the batch number and the date of the last dose are the three things the receiving doctor will want first.

Long-term safety data for daratumumab is maturing but is not as long-horizoned as it is for the antibodies of the 1990s. Where the honest answer to “what happens in fifteen years” is that it is still being observed, that is what the treating team should say.

Anyone who does not have multiple myeloma. Daratumumab acts only where CD38 is present in quantity, which in practice means myeloma plasma cells. If the diagnosis is something else, the antibody has nothing useful to attach to, and neither cost help nor access help changes that.

Concretely, it is not a treatment for solid tumours — breast, lung, colorectal, prostate, head and neck, cervical or ovarian cancer. It is not a lymphoma or leukaemia medicine: those are treated with antibodies aimed at different markers. 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.

It is also not automatic for everyone with a plasma-cell disorder. MGUS and most smouldering myeloma are monitored rather than treated. The decision to treat comes before the decision about which drugs.

Even within myeloma that does need treatment, it is not given during an active severe infection, or to anyone who has had a severe reaction to it before. Existing asthma or chronic lung disease is weighed carefully, because administration reactions hit the airway. Everyone needs hepatitis B screening first, since the medicine can reactivate a dormant infection. Live vaccines are avoided during treatment. Contraception is advised during treatment and for a period after the last dose, and that conversation belongs before the first cycle rather than after it.

Asking whether the subcutaneous form is an option instead of the drip is a reasonable question within the same molecule, and worth raising early. Asking to be put on daratumumab when the diagnosis is not myeloma is not a cost conversation — it is a diagnosis conversation.

Indicatively ₹16,000–₹25,000 for a 100 mg vial and ₹58,000–₹76,000 for a 400 mg vial as of August 2026, with the fixed-dose 1,800 mg subcutaneous vial listed at roughly ₹2.0–2.3 lakh. One intravenous dose needs more than one vial. There is no Indian biosimilar of this molecule yet, so there is no cheaper same-molecule version to ask for.

Three things about that table are worth spelling out, because they are what families get wrong when they plan the money.

• The cost is front-loaded, heavily. Dosing is typically weekly for the first eight weeks, then fortnightly, then monthly. A family that divides a total by the number of months will be short in month one and comfortable in month ten. Plan against the schedule, not against an average.
• Weight decides the intravenous cost, and nothing decides the subcutaneous cost. The drip is 16 mg per kg; the injection is a flat 1,800 mg. For a smaller adult the drip can work out cheaper per dose. For a larger adult the flat dose can be the cheaper of the two. It is arithmetic worth doing on an actual weight rather than assuming.
• The drug is one line of the bill. Day-care charges, nursing and chair time, the premedication, the partner myeloma drugs, pre-cycle blood tests and periodic marrow or imaging assessment are all billed separately, and none of them change with the form of daratumumab used. An itemised quote makes a comparison between hospitals meaningful in a way a single bundled figure never does.

A manufacturer-run patient support programme for this medicine is listed in India and administered through a pharmacy partner; the prescribing haematologist is the route into it, and terms change from time to time. Government scheme ceilings such as Aarogyasri are set against a protocol rather than a brand, and insurance sub-limits for injectable oncology drugs differ policy to policy. Confirm the applicable ceiling in writing before the first cycle rather than after it.

On biosimilars, the honest position as of August 2026 is that there is none in India for daratumumab. Development is under way elsewhere — Dr. Reddy’s licensed an investigational daratumumab biosimilar from Shanghai Henlius in February 2025 for other markets, and a biosimilar was approved in Russia in August 2025 — but none of that changes what is purchasable here today. The molecules that already have Indian biosimilars are set out in Immunotherapy Medicines Explained.

Because it makes cross-matching blood harder to interpret. CD38 sits on red blood cells too, in small amounts. Daratumumab coats them, and the indirect antiglobulin test — the indirect Coombs test — comes back positive. It can stay positive for up to six months after the last dose.

This is not a complication and it is not a sign that anything has gone wrong. It is a laboratory artefact of how the medicine works. But it matters at the worst possible moment: a patient with myeloma who is anaemic, arriving at an emergency department at night, needing blood.

Two habits solve it. A type-and-screen sample is normally taken before the first dose, so the laboratory has a clean baseline group and antibody screen on file. And every hospital that might transfuse afterwards has to be told the patient is on daratumumab — a note in the file, a card in the wallet, a sentence to the doctor on arrival. Blood banks have established methods to work around the interference once they know it is there. They cannot work around it if nobody mentions it.

A second, quieter interference is worth knowing about. Daratumumab is itself an IgG kappa antibody, so it can show up on serum protein electrophoresis and immunofixation and be misread as a small amount of remaining myeloma protein. Laboratories use a specific reflex assay to tell the two apart. This one affects how response is measured, not safety — but it is why a report saying “faint band persists” needs interpreting by the treating haematologist rather than by the patient reading the printout.

Same idea, different target, different disease. Every antibody medicine finds one marker and acts on it. Daratumumab finds CD38 on plasma cells. Rituximab and obinutuzumab find CD20 on B cells. Blinatumomab drags T cells onto CD19. Which one applies is decided by the diagnosis and the marrow report, never by which one sounds newest.

The closest cousin to daratumumab in design is the bispecific antibody, which does not simply flag a cell but physically brings a T cell to it — Blinatumomab: The Bispecific Antibody for Leukaemia explains how that works and why it is given by a pump rather than a drip. In lymphoma the CD20 antibodies do the same job as daratumumab against a different marker, and the newer of them is covered in Obinutuzumab: Uses and Availability in India, including which of these are actually marketed here.

What all of them share is the part patients are rarely told: they are immunotherapy. Immunotherapy at a glance sets out what the whole family does and, just as importantly, what it does not.

• Blinatumomab: The Bispecific Antibody for Leukaemia — the antibody that brings a T cell to the cancer cell.
• Infusion Reactions With Antibody Medicines: What to Expect — what a reaction feels like and how units handle it.
• Obinutuzumab: Uses and Availability in India — the later-generation CD20 antibody, and where it stands here.
• 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 and ESMO patient-education guidance; all pricing and regulatory statements are indicative and dated to August 2026, and regulatory status can change. Whether daratumumab applies to a particular patient, in which regimen and in which form, is a decision for the treating haematologist or medical oncologist.