ThromboGenics and BioInvent International present phase I results of novel anti-cancer monoclonal antibody

ThromboGenics NV (Euronext Brussels: THR) and BioInvent International AB (OMXS: BINV) today announced positive results from a Phase I trial of their novel anti-cancer monoclonal antibody TB-403 in patients with advanced solid tumours. The results were presented at the AACR-NCI-EORTC International Conference on Molecular Targets and Cancer Therapeutics in Boston, U.S. TB-403 was well tolerated with no reported dose limiting toxicity. These positive data support progression of TB-403 and further development.

The novel mechanism of action of TB-403 represents a potentially promising cancer therapy. It is a humanized monoclonal antibody directed towards placental growth factor (PIGF), expected to act by blocking the formation of the new blood vessels that are required for tumour growth. Preclinical exploration of PIGF biology suggests a role in tumour angiogenesis and metastasis and a limited role in the maintenance of normal vasculature. This mode of action could result in therapeutic benefit with an acceptable side effect profile.

The multi-centre, dose escalation study was conducted in 23 patients and was designed to both determine the maximum tolerated dose of TB-403 and to evaluate safety and tolerability in patients with advanced solid tumours. TB-403 is licensed by ThromboGenics and BioInvent to Roche under an agreement signed in June 2008.

TB-403 was shown to be well tolerated and no dose limiting toxicity was observed with doses up to 10 mg/kg weekly and 30 mg/kg every three weeks. In this patient population with advanced solid tumours, stable disease was observed in six of 23 patients. In the case of the two patients who were treated with 5 mg/kg TB-403 weekly, their disease was stable for approximately 12 months.

Detailed results of an earlier Phase I trial in healthy volunteers, also presented at the meeting, showed that TB-403 demonstrated a good safety profile with no serious adverse effects reported.

Dr. Patrik De Haes, CEO of ThromboGenics, commented: "We are very pleased that the results we have announced today have given us confidence to move forward in development of TB-403. The early efficacy data in this difficult patient population reflect the promise of this selective anti-angiogenesis approach to anti-cancer therapy. We very much look forward to continuing the excellent working relationship with both Roche and BioInvent, our partners on TB-403, and reporting the future progress of such an exciting and unique anti-cancer agent."

Svein Mathisen, CEO of BioInvent, also commented, "We are delighted that this Phase I trial has shown TB-403 to be safe and well tolerated also in patients with solid tumours. Although this is still early stage data, the results so far are encouraging and add to our excitement about the potential of this treatment as a significant step forward in cancer treatment. We look forward to progressing TB-403 into further development."