Antisoma yesterday said that it has started a Phase II US trial of AS1411 in around 70 patients with acute myeloid leukaemia that has relapsed or has been resistant to earlier treatment.

The trial will pit AS1411 against the current standard in therapy, cytarabine (Ara-C), with patients being signed up to receive either cytarabine alone, cytarabine plus 10 mg/kg/day AS1411 or cytarabine plus 40 mg/kg/day AS1411. Initial results are expected in 2008.

AS1411 is the first so-called anti-cancer aptamer to progress to Phase II trials and is believed to have potential in various blood cancers and solid tumours. It has already been tested in early-stage trials in solid tumours, with a Phase II study in kidney cancer expected to begin in the near future.

Antisoma's chief executive, Glyn Edwards, said: "We intend to explore the

potential of AS1411 in a number of cancers where new treatment

options are needed. [This should] therefore have the potential to add significantly to its value over the next couple of years."

The news should help the UK firm get back some positives after it saw its shares take a dive last month when lead drug ASA404 (formerly AS1404) failed to show a benefit in ovarian cancer. Roche, which had first refusal on AS1404 through another licensing deal with Antisoma, chose not to exercise its option to take the drug into Phase III in June 2006, but it was not left wanting for long after Swiss giant Novartis took the plunge, signing a deal worth up to $890 million to the UK firm. Antisoma is clearly hoping for more of the same from AS1411.