The deluge of data coming from the American Society of Clinical Oncology meeting in Chicago has included two poster presentations from the UK’s Antisoma touting the benefits of ASA404.

The first shows that patients with both squamous and non-squamous types of non-small cell lung cancer experienced a survival benefit in Phase II trials with ASA404, which is partnered with Novartis. It involved a retrospective analysis of data from trials in which ASA404 was added to carboplatin and paclitaxel chemotherapy.

Patients who received two different doses of ASA404 with their chemotherapy were pooled and compared with patients who received chemotherapy alone. Median survival data showed an extension of 4.7 months in squamous (10.2 versus 5.5 months) and of 3.9 months in non-squamous patients (14.9 vs 11.0 months). Response rates and time to tumour progression were also superior in both groups with ASA404.

The success of the mid-stage studies led to Novartis putting ASA404 into a Phase III study, named ATTRACT-1, and if this yields positive results, it is expected that filings for marketing authorisations will take place in 2011. Glyn Edwards, Antisoma’s chief executive, added that the Phase II data “have provided remarkably consistent support for ASA404 across different measures of efficacy, with different doses, and now in patients with different types of the disease”.

Findings from an earlier Phase II trial of ASA404 in prostate cancer were also presented, plus a new analysis of its effects on the prostate cancer biomarker PSA. PSA response rates were 59% with ASA404 plus docetaxel and 37% with docetaxel alone and the firm said overall, interim results from the trial are encouraging.

“A decision on next steps in prostate cancer will be made once median survival data are available,” Antisoma added. These are expected during the second half of this year.