MHRA Approves First Drug for Malignant Ascites

Korjuny (catumaxomab)What to know

30-second read

For Oncology · Palliative Medicine · Gastroenterology

Who

Adults with malignant ascites from EpCAM-positive carcinomas (ovarian, gastric, pancreatic and others) with no anticancer options left.

What’s new

Catumaxomab (Korjuny), a trifunctional antibody given as four intraperitoneal infusions — the first UK drug ever authorised for the ascites itself, not the cancer causing it.

Evidence

258-patient trial: puncture-free survival 46 vs 11 median days (HR 0.25, p<0.0001). Overall survival, a secondary endpoint, trended favourably but was not powered.

Big advantage

Quadruples the interval before the next paracentesis — each one carries real risk: a fluid leak in roughly a third of drainages, rarely bowel perforation.

Key consideration

Cytokine release symptoms can reach Grade 4 despite premedication; every infusion needs 6–24 hours of inpatient monitoring, not an outpatient visit.

Availability

UK-authorised 7 Oct 2026 via the International Recognition Procedure; launched in Germany only so far. No catumaxomab product is approved in the US.

Practice impactConsider where authorised and funded

A genuine alternative to open-ended repeat paracentesis for the right patient, where EpCAM positivity is confirmed and the admission the infusion schedule needs is deliverable. It changes nothing yet in the US, where no catumaxomab product is approved.

Read the full physician analysis

Full analysis · 9 min readMHRA approval, 7 Oct 2026 · EMA EPAR · Heiss et al., Int J Cancer 2010;127(9):2209–21

Malignant ascites has had exactly one tool for decades: paracentesis, repeated for as long as it helps and as often as the fluid returns. On 7 October 2026, MHRA authorised catumaxomab, branded Korjuny, becoming the only drug ever cleared anywhere to treat the ascites itself rather than the cancer that causes it. The regulatory story — a 2009 antibody withdrawn in 2017 and relaunched by a new owner — is a case study in its own right. For the oncologist, palliative physician or gastroenterologist who will actually see a candidate patient, the more useful questions are different: who qualifies, what the pivotal trial really showed, and what a four-infusion regimen demands of a ward before anyone reaches for it.

What paracentesis alone is already costing these patients

Malignant ascites is common and late: a Swedish registry of more than 23,000 cancer decedents found 8% underwent paracentesis in their final year of life, rising to 38% in appendiceal cancer, 35% in ovarian cancer, 26% in cholangiocarcinoma, 19% in hepatocellular carcinoma and 17% in pancreatic cancer. Once it starts, the fluid usually keeps coming back, and repeat drainage is not a benign routine. An international cohort of 111 palliative paracenteses found symptoms improved in 81% of patients by the end of drainage — but at least one harm occurred in 32%, overwhelmingly an ascitic leak at the puncture site, with four patients suffering serious harm including one fatal bowel perforation. The relief each procedure buys is temporary by design; a patient who needs paracentesis at all is, by several case series, already looking at a prognosis measured in weeks to a few months.

That is the population catumaxomab is being layered onto: not patients who will be cured by it, but patients whose remaining time is currently organised around a recurring invasive procedure with its own complication rate. A treatment that meaningfully lengthens the gap between those procedures is a different kind of benefit than tumour shrinkage, and it should be weighed as one.

An antibody designed to work only where it is injected

Catumaxomab is a trifunctional antibody: one arm binds EpCAM, an antigen many epithelial tumour cells express; the other binds CD3 on T cells; and its intact Fc region engages Fc-gamma receptors on macrophages, dendritic cells and natural killer cells. All three contacts form at once, which is also why the drug is given where it is given: directly into the peritoneal cavity, where the tumour cells and the fluid both are, rather than into the bloodstream. The label is explicit that Korjuny must never be given as a bolus or by any route other than intraperitoneal. EpCAM positivity has to be confirmed on the tumour before treatment — this is not a drug a physician can order on a clinical hunch that a cancer is epithelial in origin.

What 258 patients in one trial actually showed

The evidence behind both the 2009 and the 2026 authorisations is the same trial: Heiss et al., a prospective randomised phase II/III study of 258 patients with recurrent symptomatic malignant ascites resistant to chemotherapy, stratified into 129 with ovarian cancer and 129 with other epithelial tumours, randomised to paracentesis plus catumaxomab or paracentesis alone. The primary endpoint, puncture-free survival, favoured catumaxomab decisively: a median of 46 days against 11 days, hazard ratio 0.254 (p<0.0001). Median time to the next paracentesis specifically was 77 days against 13. Both ovarian and non-ovarian strata moved the same direction, which matters for a drug meant to apply across EpCAM-positive tumour types rather than one cancer in particular.

Overall survival was a secondary endpoint, and the honest reading is that it trended in catumaxomab’s favour without reaching significance across the full population. A prespecified subgroup of 66 patients with gastric cancer did show a significant gain — median 71 versus 44 days (p=0.0313) — and a later post-hoc analysis of the trial’s safety population reported a significant survival benefit as well. Neither of those is the headline result the drug was approved on; the regulatory and clinical case rests on puncture-free survival, and a physician discussing this with a patient should be as precise about that distinction as the trial itself was.

Catumaxomab added to paracentesis, against paracentesis alone

	Catumaxomab + paracentesis	Paracentesis alone
Puncture-free survival (primary endpoint)	46 days (median); HR 0.25, p<0.0001	11 days (median)
Time to next paracentesis	77 days (median)	13 days (median)
Overall survival	Favourable trend; significant only in a gastric-cancer subgroup (n=66) and a post-hoc safety-population analysis	Reference arm
What the procedure itself risks	Still requires intraperitoneal access for the infusions themselves	Ascitic leak in practice; bowel perforation rarely reported
Where it is available	UK (7 Oct 2026) and Germany; EU-authorised since Feb 2025	Everywhere, including the US

Trial data from Heiss MM et al., Int J Cancer 2010;127(9):2209–21 (n=258). Procedure-risk figures from a separate international cohort of paracentesis in palliative care, not the catumaxomab trial itself.

The treatment itself is not a gentler option

Korjuny is dosed as four intraperitoneal infusions — 10, 20, 50 and 150 micrograms — on days 0, 3, 7 and 10, with the full course not to exceed 21 days. Premedication with analgesics, antipyretics and NSAIDs is recommended before every infusion, and the label still warns that cytokine release symptoms — fever, hypotension, gastrointestinal upset, tachycardia, chills, respiratory and skin symptoms — can reach Grade 4 despite it. Patients need close monitoring for at least 24 hours after the first infusion and at least 6 hours after each of the following three, a schedule the treating physician can lengthen but not shorten. In practice, that is four hospital or day-unit admissions inside three weeks, not four outpatient injections. A service line that cannot staff that monitoring has not actually cleared the bar to offer this drug, whatever the marketing authorisation says.

• Confirm EpCAM status first. The label applies to EpCAM-positive tumours specifically; it is not a general-purpose ascites drug.
• Plan for admission, not an infusion slot. Four doses over up to 21 days, each requiring hours of post-infusion monitoring for cytokine release symptoms that can reach Grade 4.
• Frame the benefit precisely with the patient. A quadrupling of the gap before the next paracentesis is a real quality-of-life gain; an overall-survival benefit is not what the pivotal trial was powered to show.
• Know where it is and is not available. UK-authorised and launched in Germany; no catumaxomab product is approved in the US, and UK NHS funding and price are not yet settled.
• Paracentesis itself is not risk-free. A leak at the puncture site is common enough to count on; bowel perforation is rare but has been fatal. That risk, not just the inconvenience of repeat visits, is part of what a longer interval buys back.

What changes in the UK, and what does not change anywhere else

MHRA’s approval establishes a marketing authorisation, nothing more. Pharmanovia has launched Korjuny in Germany, its first commercial market, but has not announced a UK launch date, an NHS price, or how the drug will move through NICE or an equivalent funding route. A UK oncologist or palliative physician with an eligible patient today has an authorised drug with no confirmed way to prescribe it outside a private pathway or early-access arrangement, if one exists at all. For a US physician, the practice impact is simpler to state: none, yet. No catumaxomab product is before FDA, and paracentesis plus supportive care remains the standard everywhere this drug is not sold.

The honest summary for a clinician who manages malignant ascites is that a genuinely new option now exists on paper, for a narrow and well-defined population, with a monitoring burden heavy enough that it will not replace paracentesis so much as sit alongside it — where it is available, where EpCAM positivity is confirmed, and where a ward can deliver four admissions in three weeks. Everywhere else, for now, this approval is a fact worth knowing rather than a change to make.

Frequently asked questions

Which patients are eligible for catumaxomab?

Adults with symptomatic malignant ascites from EpCAM-positive carcinomas (ovarian, gastric, pancreatic and other epithelial tumours among them) who have no remaining standard systemic anticancer treatment options. EpCAM positivity must be confirmed on the tumour before treatment, and the label restricts prescribing to clinicians experienced in cancer medicine. It is not a cancer treatment; it treats the ascites.

How is Korjuny given, and what does it require of a ward?

Four intraperitoneal infusions — 10, 20, 50 and 150 micrograms — on days 0, 3, 7 and 10, with total treatment not exceeding 21 days. It must be given intraperitoneally, never as a bolus or by any other route. Premedication is recommended, and cytokine release symptoms can still reach Grade 4. The label calls for close monitoring for at least 24 hours after the first infusion and at least 6 hours after each later one, which in practice means an inpatient stay or a day-unit admission for every dose, not an outpatient injection.

Is catumaxomab available in the United States?

No. No catumaxomab or Korjuny product is FDA-approved, and nothing in this approval changes that. US patients with malignant ascites remain on paracentesis and best supportive care. Even in the UK, this approval establishes the marketing authorisation only — Pharmanovia has not announced NHS funding, a price or a UK launch date.