MHRA licenses catumaxomab to lengthen the gap between drainages for malignant ascites

The Medicines and Healthcare products Regulatory Agency (MHRA) has licensed catumaxomab, sold as Korjuny, for adults with malignant ascites whose cancer can no longer be treated with standard therapy. The marketing authorisations were granted to Atnahs Pharma UK Limited on 2 October, and the MHRA announced the decision on 7 October 2026 ¹.

What the approval covers

Malignant ascites is fluid carrying cancer cells that collects in the abdomen. Patients often have to return for drainage procedures, and the regulator's case for the medicine rests on lengthening the gap between those procedures ¹.

Catumaxomab is a monoclonal antibody that binds epithelial cell adhesion molecule (EpCAM), a protein found on the surface of some cancer cells, including cells in ascitic fluid. It then recruits immune cells to destroy them ¹.

The main study behind the licence enrolled 258 patients with malignant ascites and EpCAM-positive cancer for whom further chemotherapy was either unavailable or unsuitable. Patients given catumaxomab after paracentesis, the procedure used to drain abdominal fluid, went around 46 days before needing further drainage. Those treated with paracentesis alone went 11 days ¹.

The antibody is infused through a catheter directly into the abdominal cavity in four doses, each higher than the last, under the supervision of a doctor experienced in cancer treatment. The MHRA lists nausea, vomiting, diarrhoea, abdominal pain, fever, chills, fatigue and cytokine release syndrome among the common side effects ¹.

What it means for the market

The licence came through the International Recognition Procedure, the route by which the MHRA can lean on decisions already taken by other regulators rather than running a full review of its own ¹. For companies holding older or niche products with approvals elsewhere, it is a further example of that route being used to bring a medicine to UK patients.

For oncology services, the approval adds a treatment option for a group of patients with few left. Julian Beach, the MHRA's interim executive director of healthcare quality and access, said the condition "can place a considerable burden on people living with cancer, particularly when further treatment options are limited" ¹. Because the medicine is given inside the abdominal cavity through a catheter, hospitals using it would need the clinical set-up to deliver it under specialist supervision ¹.

The MHRA release says nothing about price, NHS commissioning or any NICE appraisal, so how widely the NHS will use catumaxomab, and on what terms, is not yet known ¹.

Caveats

The efficacy figures come from a single main study of 258 patients, and the MHRA reports the result as time without further drainage rather than survival ¹. The regulator says it will keep the medicine's safety and effectiveness under close review, and that the Summary of Product Characteristics and patient leaflet are to be published on the MHRA Products website within 7 days of approval ¹.