Aduro BioTech, a clinical-stage immunotherapy company, has licensed GVAX Pancreas Cancer Vaccine (GVAX Pancreas) and GVAX Prostate Cancer Vaccine (GVAX Prostate) from BioSante Pharmaceuticals, Inc. (NASDAQ: BPAX) in exchange for milestone and royalty payments after commercialization. Aduro also has an option to additional GVAX cancer vaccine indications, all for use in combination with the company's proprietary vaccine platform based on Listeria monocytogenes (Lm). Aduro initially plans to develop a novel sequential vaccine regimen for the treatment of pancreatic cancer using GVAX Pancreas and CRS-207.
CRS-207 is Aduro's lead Lm-based therapeutic and has been engineered to express the tumor-associated antigen mesothelin. CRS-207 was evaluated in a Phase 1 trial in 17 end-stage patients with cancers known to express mesothelin: mesothelioma, non-small-cell lung, ovarian and pancreatic. Analysis after the completion of the trial revealed a mesothelin-specific T cell response in multiple patients and, despite an expected survival of 3-5 months for all subjects, six out of 17 lived 15 months or longer.
GVAX cancer vaccines are based on human cancer cell lines that are genetically modified to secrete granulocyte-macrophage colony-stimulating factor (GM-CSF), an immune-stimulatory cytokine. BioSante has a portfolio of cancer vaccines, including GVAX Pancreas and GVAX Prostate. GVAX Pancreas has been evaluated in more than 120 patients and shown to be well tolerated and able to induce mesothelin-specific T cell responses.
Sequential administration of GVAX Pancreas followed by CRS-207 was first shown by Aduro to be synergistic in mouse models, demonstrating enhanced tumor-specific T cell and anti-tumor responses. Because both GVAX Pancreas and CRS-207 target the tumor-associated antigen mesothelin, the sequential administration is a heterologous prime-boost regimen. Lm is known to be especially effective in this regimen.
Based on the synergy in preclinical animal models, Drs. Elizabeth Jaffee and Dung Le of the Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins included three pancreatic cancer patients in the CRS-207 Phase 1 clinical trial who had previously received GVAX Pancreas as part of separate clinical trials. All three late-stage patients who received sequential therapy lived 15 months or longer.
Drs. Jaffee and Le have been instrumental in collaborating with Aduro to design the Phase 2 trial, which is expected to initiate in the fourth quarter of 2011 and enroll a total of 90 late-stage pancreatic cancer patients. In addition, Dr. Jaffee is one of the original inventors of the GVAX cancer vaccine platform and has many years of experience developing the vaccines.
"The synergy from the sequential administration of GVAX Pancreas and CRS-207 has the potential to significantly extend and improve the lives of a patient population where progress has historically been measured by extra weeks of survival," said Stephen Isaacs, chairman and chief executive officer of Aduro BioTech.
"We hope that this license agreement will be the first of many that can result in bringing improved cancer treatments to patients and increased value to our stockholders," said Stephen M. Simes, president and chief executive officer of BioSante. "In addition to our Pancreas and Prostate cancer vaccines, our cancer vaccine portfolio extends into breast, colorectal, leukemia, melanoma and multiple myeloma vaccines," Simes continued.
"This partnership may very well represent the future of immunotherapy," added Mr. Isaacs, "in which combination therapy becomes the standard."