GenVec, a Rockville biotechnology company, has launched a human clinical trial on a therapy it has developed to treat a leading cause of cancer death: colon cancer that has metastasized to the liver.
This is the second clinical trial GenVec has launched in its quest to get a product approved for marketing.
The company is close to wrapping up a key human trial on a gene therapy vector that it developed for cystic fibrosis.
The privately held company, which is engaged in a pioneering field of medicine called gene therapy, is hoping to show in the trial at New York Hospital in New York that the therapy is safe so it can seek Food and Drug Administration approval for wider studies to show it's effective.
The therapy uses a common virus called an adenovirus that has had a specific type of a gene inserted inside it. The virus containing the gene is injected directly into the tumors.
GenVec expects that, once inside the body, the gene will make or "express" an enzyme that converts fluorocytosine, a drug widely prescribed for fungal infections, into a potent anti-cancer agent.
Patients will begin taking fluorocytosine orally after they've gotten the adenovirus injection. The conversion should occur as the anti-fungal drug passes through the liver.
While the market for a new therapy that effectively treats colon cancer in the liver would be narrow -- about 150,000 in the United States -- the company is hoping to show that an adenovirus loaded with a specific gene could be used to treat other types of cancers that cause tumors, said Thomas D'Alonzo, president and chief executive officer of GenVec.
In the United States alone, more than 1.3 million people annually are diagnosed with those types of cancers; more than 50,000 die annually from colon and rectal cancer.
No one has shown yet in human trials that gene therapy is an effective way to treat diseases such as cancer, but numerous biotechnology and pharmaceutical companies have invested millions of dollars in developing a genetic therapy and proving it effective.
Several Maryland-based companies, including Genetic Therapy and Human Genome in Gaithersburg, are among those attempting to target the genes -- there are more than 100,000 in the human genetic system -- that can be used to treat disease.
Others, such as GenVec, are developing the delivery systems, called "vectors," to get the genes to specifically target the disease needing treatment.
