Inovio Product Pipeline: PSMA: Prostate Cancers
Product & Indication
This DNA vaccine was designed to target prostate cancers expressing the prostate specific membrane (PSMA) antigen. The plasmid vaccine is delivered into muscle tissue with the assistance of electroporation with the goal of achieving expression of the PSMA antigen.
Technical
This DNA vaccine is based on a prostate specific membrane antigen (PSMA) fused to a tetanus toxin (DOM). The PSMA antigen was designed to induce a CD8+ T-cell response capable of killing tumor cells; the DOM element was designed to help enhance the immune response to PSMA. The vaccine was given by intramuscular injection in HLA A2+ patients with prostate carcinomas, with or without electroporation.
This open label phase I/II, two arm, dose escalation trial evaluated this vaccine and delivery with and without Inovio's proprietary electroporation delivery technology. In each arm, five patients were treated at each of three dose levels (30 patients total). The protocol included three vaccinations at four week intervals followed by booster doses at 24 and 48 weeks.
As reported August 5, 2009, this study, conducted by Inovio's collaborators, the University of Southampton and The Institute of Cancer Research in the U.K., was completed. The results were published in the medical journal Human Gene Therapy, July 20, 2009, in a paper entitled, "DNA vaccination with electroporation induces increased antibody responses in patients with prostate cancer." Final conclusions include:
- The published data indicate that the use of electroporation yielded significantly enhanced antibody responses to DOM while the absence of electroporation resulted in low anti-DOM antibody responses (25-fold mean increase over baseline compared to a 1.5-fold mean increase, respectively).
- The level of antibody response further increased following additional boosts of DNA vaccine delivery via electroporation at later time points.
- Antibody responses persisted out to 18 months of follow-up.
- This vaccine was found to be safe and well tolerated.
The encouraging results have lead to Inovio's development of a proprietary dual-antigen synthetic consensus DNA vaccine encoding for PSA and PSMA, which is progressing through preclinical work toward a Phase I clinical study.
Stage of Development
Phase: I/II, treating HLA A2+ patients with prostate carcinomas. Investigator-sponsored, Southampton General Hospital, University of Southampton.
Purpose: Assess whether this DNA vaccine can stimulate patients to develop immune responses against prostate cancer and whether use of Inovio's electroporation system enhances this response.
Study Type: Interventional
Study Design: Treatment, Non-Randomized, Open Label, Dose Comparison, Parallel Assignment, Safety Study
Study Start Date: February 2005
Status: Enrollment Completed
For more information: http://www.abedia.com/wiley/record_detail.php?ID=395
Commercialization
Vaccine: owned by University of Southampton.
Delivery technology: owned by Inovio.