Rexin-G: Breakthrough in cancer therapy

Michael Miller, an American businessman from North Carolina, was diagnosed with pancreatic cancer in May 2003. He underwent standard chemotherapy that started in June and continued until January this year. "About October or November last year, I read about Rexin-G and Dr. Erlinda Gordon who developed this product," Miller relates. "Through other family members who were involved with the University of Southern California where Dr. Gordon was a faculty member, we were able to make some connections."

In April 2004, Miller came to the Philippines where three Filipino cancer patients had already previously received the intervention. "The standard, traditional chemotherapy, which I had earlier, held my cancer at bay, but it took a toll on me physically," Miller recalls. "Since coming here and taking the gene therapy, the tumor in my body had been reduced by 50 percent. The tumor that had metastasized in the liver had disappeared. Now, I have less cancer than what I had a year ago when I was diagnosed. We are seeing positive results and we plan on continuing this."

"His response is quite remarkable," says Dr. Gerardo Cornelio who, together with Dr. Conrado Lorenzo III, had been conducting the clinical study here. The very first human to receive the intervention was a Filipino. "It began with a plea from a man whose wife was suffering from terminal pancreatic cancer," Dr. Gordon relates. "He learned about our gene therapy clinical trials through the Internet and hoped that his wife might be able to participate. Responding to the urgency of his request, we arranged with Epeius Biotechnologies Corp. to export the Rexin-G targeted vector and to open a compassionate use clinical trial in a world-class tertiary care hospital in the Philippines."

Epeius Biotechnologies Corp., the privately-held biopharmaceutical company that is focused on the research, development, and commercialization of the TDS (targeted delivery system) technology, was founded by Dr. Frederick L. Hall, president and CEO of Epeius, and Dr. Erlinda M. Gordon, Epeius medical director and VP for operations and medical affairs. Dr. Hall, an American biochemist and biophysicist, and Dr. Gordon, a Filipino-American physician and scientist, together undertook the pioneering scientific and medical study that is hoped to benefit cancer patients where other conventional medicine had failed.

"The approach of the gene therapy technology is a lot better than the traditional chemotherapy treatments," Miller says. "Standard chemotherapy attacks the whole body. It gets your white blood cells. It gets your red blood cells. It makes you weak. It causes your hair to fall out. It’s a difficult thing to go through. While it’s trying to kill the cancer, it’s killing you at the same time. But with gene therapy, there has been no side effects whatsoever. As a result, in the past six weeks, my hair has started to grow back. My blood work is fine. I come back from the hospital after my morning treatment and jump on the treadmill for an hour and a half. I can do the things I was doing about a year and a half ago prior to being diagnosed with cancer."

"Targeted gene therapy only goes to the area of the cancer and not anywhere else," Dr. Gordon explains. "It only affects the cancer cells and not anything else. So that’s the big difference between the chemotherapy and the gene therapy that we are using. Doctors infuse tumor-targeted ‘smart’ nanoparticles engineered to transport genetic medicine selectively to sabotage cancer cells and their blood supply without causing serious side effects. This built-in safety feature of Rexin-G of selectively killing only the tumor cells while sparing the normal cells and tissues of the body enhances the quality of life of the cancer patients. Since it is targeted like a laser‚ or a guided missile‚ there is less collateral damage‚" Miller interjects.

The clinical study combines state-of-the-art genetic medicine with a radically new delivery system. "This is the first truly effective targeted delivery system (TDS) that can be injected directly into a vein and deliver genes and/or molecular therapeutics preferentially to cancerous tumors that have spread throughout the body (metastatic cancer) without eliciting systemic side effects or organ damage," Dr. Gordon explains. "These features make the targeted vectors more effective and less toxic than conventional medicines."

Rexin-G gained US FDA orphan drug approval for pancreatic cancer in the fall of 2003, providing further product validation and exclusivity in the marketplace. Rexin-G is the first targeted injectable gene therapy vector that has been approved by both the US FDA and the Philippine BFAD for use in Phase I/II cancer clinical trials for safety and efficacy.

"The first patients receiving intravenous infusions of the TDS-encapsulated genetic ‘bullets’ responded favorably without serious side effects," a report says. "This represents a momentous landmark in Philippine history – for Philippine physicians and US scientists to team up as pioneers and world leaders in the advancement of genetic medicine."

The thing that is spectacular about this is that it’s here in the Philippines and the US honored it by giving us the FDA drug approval, which actually stimulated a lot of American interest. "Which is why people like Mike is here," Dr. Gordon remarks. "We have a breakthrough technology and our primary purpose is to be able to advance the benefits."

"Pancreatic cancer is one of the most difficult cancers to deal with," Miller notes. "If it shows promise in pancreatic cancer, it’s going to show promise in a lot of others, including breast cancer and colon cancer. So this can be the answer to a lot of people’s problems."