Listeria Vaccine For Cervical Cancer Found Safe
Researchers testing a vaccine based on the live bacteria Listeria, in women with advanced cervical cancer found it to be safe. The Lovaxin C vaccine being developed by Advaxis Inc. (OTC Bulletin Board: ADXS), is intended to treat cervical cancer and head and neck cancers that result from the human papilloma virus (HPV). This marked the first time the vaccine had been treated in humans.
"Our long held belief that live Listeria vaccines are safe, even in end stage cancer patients, has been confirmed with the results from our recent Phase I/II study. We have just entered the age of safe bacterial therapies," said Dr. John Rothman, VP of Clinical Development.
The immune response that Listeria generates is called "cellular" immunity, the type needed to attack cancer. Listeria is one of the strongest stimulators of cellular immunity known. "By redirecting it against specific tumor types safely, we have created a new, and potentially very effective, class of cancer therapy," says Rothman.
Advaxis reported treating fifteen patients in three dosage groups with thirty-minute 250 ml infusions of Lovaxin C at three-week intervals. Patients were observed for a total of 111 days. With the exception of two women, all patients had had either stage IVb advanced, recurrent, or progressive cervical cancer.
Every patient experienced a flu-like syndrome in the three-to-twelve hours after dosing comprised of fever, chills, nausea, and occasional vomiting, which is consistent with immune stimulation. In the lower two doses, symptoms were well tolerated and resolved with the use of over the counter analgesics and antihistamines.
Although efficacy was not a primary focus of the trial, efficacy findings were obtained. Of the seven stable patients, three had reductions in their tumor mass subsequent to treatment. While most lesions increased in size, tumor reduction was seen in a number of lesions and two tumors disappeared completely.
One patient with IVb cancer, who had failed two prior courses of chemotherapy and a course of radiation was deemed sufficiently healthy to resume chemotherapy undergo surgery after receiving the vaccine and was removed from the trial early for this purpose and currently tumor free.
"This milestone has given us the direction for the continued development Listeria-based vaccines," said Rothman. Further vaccines in development target breast, ovarian and lung cancers.