immatics, a biopharmaceutical company that specializes in the development of peptide-based immunotherapeutic substances for the treatment of cancers, announced the successful conclusion of its first phase 1 clinical study on vaccine IMA901 against renal cell cancer.

IMA901 is a combination of 10 different peptide antigens that can be identified as so-called tumour-associated antigens among the majority of renal cell cancer patients. The purpose of these antigens is to specifically activate the human immune system against cancer cells, thus mobilizing the body's own self-defense mechanisms.

The study, which was conducted in six clinical centres in Germany, the United Kingdom and Switzerland, investigated the immunological efficacy of the therapeutic vaccine (secondary endpoint), in addition to its safety and compatibility (primary endpoint). Tests on 28 patients clearly showed that IMA901 was not only safe and well-tolerated, but in over 70 percent of the patients treated additionally evoked immune responses against tumour-associated antigens included in IMA901. Moreover, the formation of immune responses against multiple (=2) targets correlated significantly with a stabilization of the disease and a decline in the tumour burden identified prior to commencement of the treatment (p<0.05).

immatics Chief Medical Officer Dr. Jürgen Frisch comments: "The results we achieved far surpassed immatics' expectations and are prompting us to lay the cornerstone for evidencing clinical efficacy by commencing a Phase 2 trial as early as possible."

Prof. Dr. Arnulf Stenzl, Director of the Urological Clinic at the Tübingen University Hospital, adds: "Our hope that IMA901 might be a highly promising candidate for immunotherapeutic treatment of advanced renal cell cancer was fully confirmed by the Phase 1 results. In particular, the interrelationship that was identified between the immune response and the clinical response underscores IMA901's potential for further successful clinical development in connection with this serious disease."

Less than three years since the beginning of early preclinical development of IMA901, the positive results of the Phase 1 study that have now been obtained have laid the cornerstone for swiftly commencing a Phase 2 investigation to demonstrate the efficacy of IMA901. Further peptide-based product candidates from immatics for other common cancers are nearing the conclusion of the preclinical investigations and should be entering the clinical development stage beginning in 2007. The next step will be a clinical investigation of therapeutic vaccine candidate IMA910 for the treatment of colon cancer.