BioWorld International Correspondent

PARIS - A new firm has been established to develop cell therapy products derived from modified T cells for leukemia and severe autoimmune diseases such as scleroderma, multiple sclerosis and rheumatoid arthritis.

Called LTKfarma, it was founded in March and has a lead product in Phase I/II trials. It also has appointed a seven-member advisory board.

Based at the Genopole, France's national biotechnology science and business park at Evry, LTKfarma is exploiting intellectual property licensed to it by Pierre and Marie Curie University in Paris. That IP consists of exclusive worldwide rights to 31 patents (26 of which already have been granted).

Its lead product, TK54, is being developed to reduce the risks linked to graft vs. host disease (GVHD), one of the main complications of bone marrow grafts that result in death in a significant proportion of cases.

TK54 consists of modified T cells that express suicide genes. The genes code for a viral enzyme, the herpes virus thymidine kinase (TK), which is able to transform chemically an inactive drug (ganciclovir, usually used for herpes infection) into a derivative that is toxic to dividing cells, which then die by apoptosis. Hence, the target cells into which the TK gene is introduced only die if they are in the presence of ganciclovir and are in division.

That is the case of T cells present in a bone marrow graft, which frequently are the cause of GVHD. The first application of TK54 is targeting bone marrow grafts in patients suffering from leukemia and autoimmune diseases. The treatment entails injecting modified T cells expressing TK, followed by treatment with ganciclovir if GVHD occurs.

The chairman of LTKfarma, Laurent de Narbonne, general manager of Octapharma in France, Belgium and Luxembourg, and who is a member of LTKfarma's advisory board, said the company's first priority is to accelerate the clinical development of TK54 and raise funds for Phase II/III trials.

He told BioWorld International that he would start approaching venture capital firms this fall to raise €4 million (US$5.1 million) to €6 million, adding that the Phase II/III trial of TK54 probably would start in 2008.

Meanwhile, he said, the Phase I/II trial under way in Paris should be completed in the first half of 2007. After that, a second Phase I/II trial would be carried out, starting in spring 2007 and ending in mid-2008.

The Phase I/II trial under way is being financed by the Paris public hospital authority (AP-HP) and the French Muscular Dystrophy Association (AFM), which between them are providing €1.5 million solely for that purpose, while LTKfarma itself received a €450,000 grant from the Ministry of Research as winner of an innovative project competition last year. Narbonne pointed out that LTKfarma would repay the funding provided AP-HP by buying back the results of the trial

He also suggested that the potential market for TK54 ran into hundreds of millions of dollars, saying that one of its merits would be to broaden the potential number of donors from whom a leukemia patient could obtain a bone marrow transplant.