A Phase Ii Study Of Abr-214936 (Anatumomab Mafenatox) Tumour Targeted Superantigen (Tts) Therapy In Patients With Advanced Adenocarcinoma Of The Pancreas.

3162 Tumour Targeted Superantigen therapy is a novel form of cancer therapy. The principle involves targeting the superantigen with subsequent activation of cytotoxic T cells in tumor tissue. ABR214936 is a recombinant fusion protein of a mutated Staphylococcal enterotoxin A and a Fab moiety recognising the oncofetal antigen 5T4 expressed in the majority of pancreas cancers. In this open non controlled phase II study pts with histologically confirmed pancreas adenocarcinoma, measurable disease and good PS are treated with a daily 3 hour infusion of ABR214936 for 4 consecutive days. Pre-formed circulating anti-SEA antibodies neutralise the effects of ABR-214936 and so dosing is adapted to the pre-existing antibody-titre. Each patient is treated with an individual dose based on the pre-treatment anti-SEA antibody concentration and adjusted to body weight. A second cycle is given 4–6 weeks later when the dose is adjusted to the new titre. Evaluation is by means of a pre treatment CT scan repeated at D56 and D112 to evaluate tumor response. Side effects include pyrexia, rigors, nausea, vomiting, and hypotension. If a drug-related AE SAE occured the dose for the next infusion is decreased to 75%, if a further reaction then reduced to 50%. Treatment is well tolerated with no withdrawns due to toxicity. Approximately 26% experienced a drug related AE most commonly grade 1- 2 pyrexia. 20 pts recruited, 12 had 2 cycles, 7 only 1, 1 withdrew consent. 18 had received gemcitabine based chemotherapy, 1 5FU and 1 RT. At D56 6 pts had SD, 7 PD and 7 had died. At D112 2 pts had SD. Both previously treated with gemcitabine chemotherapy. ABR214936 is a promising and active agent in this difficult to treat cancer. It has been demonstrated to be safe and well tolerated. Follow-up is ongoing. No significant financial relationships to disclose.