By Mary Welch
Aphton Corp. will start Phase III trials for metastatic pancreatic cancer with a combination immunochemotherapy regimen of its anti-G17 immunogen and gemcitabine (Gemzar) vs. gemcitabine.
Gemcitabine, a chemotherapeutic, is the current standard of care for pancreatic cancer in the U.S. However, that is not the case in some European countries. In clinical trials, the anti-G17 immunogen has been shown to increase median survival by five weeks, from 4.4 to 5.65 months.
The first Phase III trial will take place at the University of California at Los Angeles and will be harmonized with the European trial.
The second trial, in the UK, will be for the treatment of advanced pancreatic cancer. The company's anti-G17 immunogen will be tested directly against gemcitabine. Although the majority of patients will be in the UK, patients will be enrolled throughout Europe.
Miami-based Aphton's antigastrin therapy induces a directed antibody response against gastrin and other gastrin-related growth factors. Gastrin is a central hormonal growth factor that stimulates gastrointestinal cancers to proliferate and spread.
A Phase II trial of 30 evaluable patients in the UK showed that the overall median survival was 6.7 months. This median survival compares favorably with published data showing median survival of about 4.3 months for patients with advanced pancreatic cancer who either received no additional therapies or did not respond to additional therapies. The overall median survival of patients treated with antigastrin vaccine was 56 percent greater than the baseline median survival of 4.3 months. In addition, those patients who responded to the antigastrin vaccine showed that median survival increased to 7.3 months, which was 70 percent greater than the baseline median survival.
There are more than 88,000 new cases of pancreatic cancer diagnosed in the U.S. and Europe each year. Overall, the prognosis is very poor. Most have advanced disease at the time of diagnosis and are considered incurable, with a very short median survival time.
In the U.S., patients diagnosed with all stages of pancreatic cancer have five-year survival rates of only 4 percent. Aphton believes its antigastrin vaccine approach can extend patient survival without adding to toxicity.
The antigastrin vaccine induces antibodies in patients that block the central growth factor in pancreatic cancer, gastrin-17. This gastrin-17 neutralization slows the proliferation and spread of pancreatic cancer.
Aphton's stock (NASDAQ:APHT) closed Tuesday at $31.50, down 50 cents.