EVRY, France, November 7 /PRNewswire/ -- DNA Therapeutics S.A. announced today that an abstract of its presentation at the 18th EORTC-NCI-AACR Symposium “Molecular Targets and Cancer Therapeutics” (Prague) is now on line (http://www.fecs.be/emc.asp?pageId=1321). The presentation itself will be available from November 10 onwards at (http://www.dna-therapeutics.com/content.php?idcontent=events&lg=en).
Xenografted nude mice proof of concept: Kaplan Meier median survival for nude mice grafted with human tumor cell lines (head & neck squamous cell cancer, melanoma), treated by intra-tumoral Dbait, in association with radiotherapy, at nil, 1, 3 and 6 nanomoles, is dose dependent and respectively of 61, 93, 129 and > 150 days. Hazard ratios, compared to the nil group, are 0.42 (p<0.01), 0.28 (p<0.0004), 0.18 (p<0.000004). MRI follow-up of mice shows therapy induced necrosis of the tumor with Dbait superior to radiotherapy alone.
How does Dbait work: Cancer therapies induce DNA double strand breaks (DSBs), but unfortunately cells possess DNA repair complexes which are attracted to these breaks, and repair them. Dbait is a short inhibiting DNA (siDNA) which mimicks DSBs, diverting them from their primary objective, and allows cancer cells to be killed.
Physico-chemical facts: The Dbait used is a 32-bp double stranded modified DNA molecule. Its activity is length/structure dependent (mimicking a break) and not linked to the nature of its sequence.
Biological facts: Before going into nude mice, DNA Therapeutics demonstrated that in vitro Dbait inhibits religation of DNA fragments, and traps one of the first elements of the repair complexes: the Ku70/Ku80 heterodimer. From then on the repair system is completely disorganized: DNA-PKcs is activated, and histone H2AX is phosphorylated, but they fail in their repair task.
Commercial potential: J.S. Sun, CEO of DNA Therapeutics said: “we have already had a first meeting with regulatory authorities. We expect to initiate clinical trials by 4Q07/1Q08. In view of the breadth of indications open to us, and of course if we continue to meet with success, peak sales are expected beyond the $ 1 billion range”.
About DNA Therapeutics S.A.: DNA Therapeutics S.A., founded in May 2006, as a spinoff from the Curie Institute, the CNRS, the INSERM (French NIH) and the Museum National d’Histoire Naturelle, is the premier corporation developing DNA baits to trap and inhibit enzyme complexes involved in DNA repair. It is headquartered in the Genopole Science Park (Evry, France).
Web: http://www.dna-therapeutics.com
DNA Therapeutics SA
CONTACT: Contacts: Pr.Jian Sheng Sun, Ph.D., Chairman and CEO,+33-624-753-239, sun@dna-therapeutics.com; Tony Marcel, MD, PhD,Vice-Chairman of the Board, +33-147-556-195, cell +33-609-165-382,marcel.tony@wanadoo.fr; Web: http://www.dna-therapeutics.com