REO 006 was an open-label, dose-escalation Phase I study of locally administered REOLYSIN® in combination with radiotherapy in patients with advanced malignancies. Twenty-three patients were enrolled in the study. Each received between two and six intratumoural injections of REOLYSIN® at escalating dosages in combination with either a low (20 Gy) or a high (36 Gy) constant dosage of localized radiotherapy. The primary objectives of the trial were maximum tolerated dose, dose limiting toxicity, and safety. A secondary objective was to examine any evidence of anti-tumour activity.
Results from the study were published in the online version of the journal Clinical Cancer Research in May 2010. Of the seven evaluable patients in the low-dose (20 Gy) radiation group, two patients had a partial response (PR) (esophageal adenocarcinoma and squamous cell carcinoma (SCC) of the skin) and five had stable disease (SD), including patients with malignant melanoma, pancreatic adenocarcinoma, SCC of the larynx and SCC of the skin (two). In the high-dose (36 Gy) radiation group, five of seven evaluable patients had PRs (two with malignant melanoma and one each with lung adenocarcinoma, colorectal adenocarcinoma and ovarian adenocarcinoma) and two had SD (malignant melanoma), for a clinical benefit rate (PR plus SD plus complete response (CR)) of 100%. The treatment was tolerated well in all cohorts, with no dose-limiting toxicities, and no maximum tolerated dose was reached.