New Law Blogs

Listeria May Play a Role in the Fight Against Cancer

By Pritzker | Ruohonen

Listeria, an often-fatal foodborne pathogen, may be useful in the fight against cancer. According to research done by Advaxis Inc., a live Listeria cancer vaccine, Lovaxin C, may have helped 15 women with advanced cervical cancer:

“We are using Listeria to deliver tumor-specific antigens to the immune system in a manner that we feel results in maximal immune and tumor-clearing response,” said John Rothman, PhD, vice president of clinical development at Advaxis, which is developing Lovaxin C.

The trial included 15 women with progressive, recurrent or advanced cervical cancer. All patients had failed chemotherapy, radiotherapy or surgery. The women had metastatic disease and most were stage IVb.

Listeria monocytogenes infects antigen presenting cells (APCs) — “a very special piece of immune real estate,” Rothman said. These cells instruct the immune system what to attack. Listeria thrives within APCs and Advaxis’ Lovaxin vaccines have the ability to direct a strong immune attack against whatever tumor target is bioengineered into the vaccine. Lovaxin C is engineered as a therapy for people who have cancer caused by HPV.

“We bioengineer Listeria both to attenuate it and to cause it to secrete a tumor-specific antigen fused to a listerial protein, which makes it more effective than Listeria that just secretes the tumor antigen,” Rothman said. “By doing this we focus a very strong immune attack against the antigen in question, which is typically specific to a tumor.

“What we’re doing is taking advantage of millennia of evolution that enabled Listeria to infect human immune systems, and an equal amount of evolution that enables humans to get rid of Listeria once this occurs. We are then co-opting and redirecting all of these complex immune responses and targeting them against cancer,” Rothman said.

The above quote is from an Advaxis press release.  At the bottom of the press release it states, "At the time of this writing, 6 of 13 patients evaluable for efficacy are still alive."  (Reality check: Clinical studies aren't about drugs; they are about people.) We hope additional research and development will produce a cure for this deadly cancer.

Full post as published by Food Poisoning Law Blog on April 23, 2008 (boomark / email).