Argos Therapeutics today announced that it has initiated dosing of patients in a phase 2b clinical trial of its Arcelis personalized immunotherapy for the treatment of HIV patients, AGS-004.

The phase 2b trial is a multi-centre, randomized, double-blind, placebo-controlled study in HIV infected patients receiving Anti-Retroviral Therapy (ART) to evaluate the efficacy and safety of AGS-004 when compared to placebo during an analytical treatment interruption of ART. The trials primary objective is to compare AGS-004 with placebo and the anti-HIV effects of AGS-004 as measured by the new plasma HIV viral load set point established at the end of the 12 week analytical treatment interruption.

The initial two patients in the trial have been treated by Jeff Jacobson, MD, principle investigator of the study at Drexel University in Philadelphia. A total of 42 patients are expected to be enrolled in the phase 2b trial. Nine sites in North America are participating in the trial, which is funded by the National Institutes of Health, as part of a $28 million contract that Argos was awarded in 2006.

“The phase 2b trial will further demonstrate that AGS-004 is an effective and safe alternative treatment for HIV patients,” said Jeff Abbey, president and chief executive officer of Argos. “Our RNA-loaded, dendritic cell-based immunotherapy is perfectly matched to each patients unique HIV viral burden, allowing for a remarkable decrease in viral diversity post-AGS-004 treatment.”

Data from the phase 2 a trial of AGS-004 demonstrated a substantial reduction in viral load set point during ART treatment interruption compared to pre-ART levels, and an unexpectedly long time to viral rebound after withdrawal of ART. The treatment was well tolerated with no significant adverse events related to AGS-004 reported.

Arcelis is Argos proprietary technology for personalizing RNA-loaded dendritic cell immunotherapies for HIV, other infectious diseases, and cancer. This platform is based on optimizing a patients own (autologous) dendritic cells to trigger a pathogen- or tumour-specific immune response. To address the challenge of the unique genetic profile of each patient disease and the genetic mutations of that disease, Argos loads the autologous dendritic cells with a sample of messenger RNA (“mRNA”) isolated from their disease. Through this process, dendritic cells can potentially prime immune responses to the entire antigenic repertoire, resulting in an immunotherapeutic that is customized to the patient specific disease.

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