Medannex Presents Further Positive Clinical Data for MDX-124 at ESMO 2026

Updated phase 1b results demonstrate 60% disease control rate, encouraging anti-tumour activity and excellent safety profile for first-in-class therapy.

Medannex Ltd (Edinburgh) today announced the presentation of updated clinical data from Module 1 of the ongoing ATTAINMENT study of MDX-124 at the European Society for Medical Oncology (ESMO) Congress 2026 in Madrid.

The updated results provide further evidence of the encouraging anti-tumour activity and excellent safety and tolerability of MDX-124, Medannex’s first-in-class antibody targeting annexin-A1, in patients with advanced solid tumours who had exhausted all existing treatment options.

Building on the preliminary findings presented at ESMO 2025, the latest data demonstrate a disease control rate of 60% in evaluable patients, compared with 55% previously reported, including a confirmed partial response.

Key findings include:

• Disease control rate of 60% (9/15) in evaluable phase 1b patients with MDX-124 monotherapy.
• Confirmed partial response in a patient with advanced metastatic cholangiocarcinoma, who remained on MDX-124 monotherapy for approximately 12 months.
• Excellent safety and tolerability, with no grade 3 or higher treatment-related adverse events or dose-limiting toxicities observed across 21 treated patients.
• Recommended Phase 2 dose established at 20 mg/kg administered every two weeks.

The results are particularly encouraging given that patients enrolled in Module 1 had advanced cancers and had received a median of three prior treatment regimens.

Module 2 of the ATTAINMENT study is now underway, evaluating MDX-124 in selected tumour types. This includes a monotherapy arm in biliary tract cancer, for which enrolment commenced in Q1 2026, and a combination therapy arm in newly-diagnosed advanced pancreatic cancer, investigating MDX-124 alongside gemcitabine and nab-paclitaxel, due to begin enrolment in Q4 2026.

Professor Daniel Palmer, Chief Investigator of the ATTAINMENT study and Director of the Liverpool Experimental Cancer Medicine Centre, commented: "The disease control and excellent safety profile we have observed strongly support the continued investigation of MDX-124 in selected tumour indications, both as a monotherapy and in combination with established cancer treatments."

Medannex CEO Ian Abercrombie added:

We are delighted that the clinical data continue to build on the positive results presented at ESMO last year. Achieving disease control in 60% of evaluable phase 1b patients, with tumour shrinkage and no serious toxicity, is extremely encouraging for a first-in-class therapeutic at this stage of clinical development. We remain committed to advancing our programmes, with the goal of bringing much-needed new treatment options to patients as soon as possible.

The poster presentation can be viewed here: https://medannex.org/wp-content/uploads/2026/10/261007-ATTAINMENT-ESMO-Congress-2026-Poster-Final.pdf