By Lisa Seachrist
WASHINGTON — Amarillo Biosciences Inc. has opened enrollment in two multicenter Phase III studies aimed at evaluating low-dose oral interferon as a treatment for dry mouth associated with Sjogren's syndrome.
The studies will be the first Phase III trials of low-dose interferon, which the Amarillo, Texas-based company is developing for a number of indications, including Sjogren's, fibromyalgia, oral warts in HIV-positive patients and hepatitis.
"What we are doing, in effect, is natural," said Joseph Cummins, president and CEO. "It boggles my mind that people are treated with millions of units of injectable interferon, when nature makes low doses in the nasal passages and that drips down to receptors in the throat. This is a non-toxic, inexpensive way to administer it."
Alpha interferon is a critical immune system modulator. High-dosage injections of the drug are currently approved for use in patients with cancer, multiple sclerosis and hepatitis.
Sjogren's syndrome is an autoimmune disorder that attacks the moisture-producing glands in the body, leaving patients with a dry mouth and dry eyes. Sjogren's can also damage the kidneys, blood vessels, lungs, liver, pancreas and brain. Sjogren's affects 2 million to 4 million Americans, 90 percent of whom are women.
The two double-blind, placebo-controlled Sjogren's studies will involve 250 patients each and 25 centers each. Half of the patients will receive a 150-unit alpha interferon lozenge three times a day for six months, while the other half will take a placebo lozenge three times a day. At the end of six months, patients will have the opportunity to enter an open-label phase, and receive the oral interferon for six months.
The first phase of the studies is expected to finish in late 1999, with the six-month follow-up to be completed in 2000. Cummins said the company plans to file a biologics license application in 2000, and hopes for approval the following year.
"If our studies show efficacy, which I predict they will, we shouldn't have too much trouble," Cummins said. "The agency has already approved interferon in large doses for injection. This is simply less toxic."
Cummins started the company in 1984, after his mother-in-law had a complete regression of a malignant melanoma following treatment with oral doses of bovine alpha interferon, which Cummins had prepared from the nasal secretions of hundreds of calves. Because the preparations weren't pure enough to inject, his mother-in-law took the interferon orally.
"Advanced melanoma is such a severe disease," Cummins said. "There was some literature saying that oral interferon was active. What else are you going to do?"
Cummins said his company isn't currently working in oncology for a number of reasons, including the expense of such work. However, he noted, Amarillo is looking for U.S. partners for current indications as well as oncology indications.
"We have excellent Japanese partners," Cummins said. "But we don't have any partners for America yet."
Hayashibara Biochemical Laboratories Inc., of Okayama, Japan, produces the oral interferon for Amarillo Biosciences and is a significant shareholder in the company.
Amarillo's stock (NASDAQ:AMAR) closed Tuesday at $1.062, unchanged. *