New data from Argos AGS-003, sunitinib Phase 2 combination study on RCC presented at ASCO

Argos Therapeutics today announced that new data from its Phase 2 combination study of its Arcelis™ immunotherapy for the treatment of renal cell carcinoma (RCC), AGS-003, in combination with sunitinib showed improvement over expectations for sunitinib alone in progression-free survival (PFS) in newly diagnosed metastatic RCC patients with unfavorable prognosis. Induction of anti-tumor (CD28+) memory T cell responses correlated with PFS and all patients that were analyzed in the study demonstrated a decrease in circulating regulatory T cells. There were no safety issues or additive toxicity of AGS-003 in combination with sunitinib. Data were presented by Dr. Robert Figlin, director of the Division of Hematology/Oncology at the Cedars-Sinai Samuel Oschin Comprehensive Cancer Institute, in a poster and a discussion session at the 2011 Annual Meeting of the American Society of Clinical Oncology (ASCO) in Chicago.

The median overall PFS for patients in the Phase 2 combination study was 11.9 months compared to historical PFS for sunitinib alone of up to 8.0 months in unfavorable risk advanced RCC patients. Eleven of 15 had increases in the anti-tumor CD8+CD28+CD45RA- population(effector/central memory T cells) post-AGS-003 treatment. This showed that immunity to unique tumor antigens contributed to longer PFS. Additionally, six patients monitored for regulatory T cells (CD4+CD25+CD127-FoxP3+) showed a decrease following AGS-003 treatment which also demonstrated a positive correlation with PFS. Safety measurements from the study indicated that AGS-003 as a combination therapy with sunitinib was well tolerated with the majority of AGS-003-related adverse events being mild injection site reactions. AGS-003 was not associated with other adverse events beyond those expected with sunitinib.

"The continued positive trend in regulatory T cell reduction and prolonged PFS is encouraging as it is accompanied by an increase in anti-tumor memory T cells and a good safety profile," said Dr. Figlin.

"A randomized, global Phase 3 clinical study to evaluate AGS-003 plus sunitinib versus sunitinib alone in patients with newly diagnosed advanced RCC who will undergo nephrectomy is planned to confirm these positive results."

Jeff Abbey, president and chief executive officer of Argos, said, "Clinical efficacy in advanced RCC patients with current treatments is still limited. Results from the study show that AGS-003 is a promising therapeutic option for this underserved group of patients. We look forward to initiating the global phase 3 study later this year and advancing this promising, completely personalized, immunotherapy platform in RCC and beyond."