Argos Therapeutics announced that its Arcelis immunotherapy for renal cell carcinoma (RCC), AGS-003, demonstrated favourable progression-free survival (PFS) and safety in combination with sunitinib, based upon updated results from an ongoing phase-2 trial.

The interim data demonstrated positive median PFS results in unfavourable risk, newly diagnosed, metastatic RCC (mRCC) patients. The median PFS was 14.9 months for intermediate risk and six months for poor risk mRCC subjects, which compares favourably to historical results with sunitinib alone in unfavourable risk patients. In addition, treatment was well tolerated with no serious or grade 3/4 adverse events attributable to AGS-003. Data were presented in a poster at the Ninth International Kidney Cancer Symposium in Chicago. Full data will be presented following the completion of the study.

“The observed PFS for AGS-003 plus sunitinib is encouraging in this unfavourable prognosis group of patients,” said Robert A Figlin of Cedars-Sinai´s Samuel Oschin Comprehensive Cancer Institute and lead author. “Further study of this combination in a randomized setting versus sunitinib alone is warranted to confirm these promising results.” Twenty-five patients with newly diagnosed, clear cell mRCC were enrolled in the study, of which 22 received at least one dose of AGS-003. Following nephrectomy, patients initiated standard sunitinib therapy (daily for four weeks, followed by two weeks off). After a minimum of one sunitinib cycle, patients then received concomitant AGS-003 injections every three weeks for up to five doses, and every three months thereafter until disease progression or end of study.

Jeff Abbey, president and chief executive officer of Argos, added, “AGS-003 possesses all of the tumour antigens, including the patient’s unique mutated antigens, in order to produce the broadest possible immune response, limit tumour escape, and induce immunologic memory relevant to each patient. AGS-003 is engineered to overcome the inherent immunosuppression caused by cancer and deliver the potential for a highly personalized response to improve patient outcomes. We look forward to continued follow-up from this study to support the encouraging findings thus far. We also anticipate initiating a large, randomized and controlled clinical study for AGS-003 in combination with sunitinib in 2011.”

The study´s primary endpoint is to evaluate clinical activity as measured by objective tumor response. Secondary endpoints included safety, clinical benefit (SD, PR and CR), immunologic response, and assessment of both progression-free and overall survival.

Arcelis is Argos´ proprietary technology for personalizing RNA-loaded dendritic cell immunotherapies for cancer, HIV and other infectious diseases.

Argos is an immunotherapy company developing new treatments for cancer, infectious and autoimmune diseases, and transplantation rejection.