By Jim Shrine
Maxim Pharmaceuticals Inc. completed enrollment in record time for its U.S. Phase III trial in advanced malignant melanoma, one of three ongoing pivotal studies of Maxamine.
The study, which began in July 1997, is fully enrolled at 300 patients. That means it will be completed by this time next year, since the trial calls for 12 months of treatment.
"We're proud this is the fastest-enrolling malignant melanoma trial that's been run," Larry Stambaugh, Maxim's chairman and CEO, told BioWorld Today. "We anticipated we would be able to do that. Based on the Phase II data, we thought the investigators' enthusiasm would be there to enroll in this time frame."
Phase II data showed Maxamine Therapy extended median survival more than twice as long as conventional therapy - 15 months vs. seven months. The results were even more pronounced in patients with liver metastasis, whose survival increased from four months to 19 months.
The primary endpoint in the Phase III trial is survival. Secondary endpoints include tumor response rate, duration of response, and quality of life for patients.
Stambaugh said enrollment was speeded because the number of clinical sites eager to participate in the study was larger than originally expected, and that helped boost the number of patients from 240 to 300. Benefits of the increased patients and sites include ensuring enough evaluable patients are involved; building awareness of the product through additional sites, which can help generate a quick launch; and increasing the potential for statistical significance.
Maxamine Heading Toward Product Application
"This advances Maxamine to the next level," Stambaugh said. "With the first trial enrolled, we're moving toward completing that study and making a first product application. Based upon the growing body of human data in a number of cancers and viral infections - and now topical indications - it appears the Maxamine discovery can play an important part in immunotherapy."
Enrollment in an international Phase III trial in the same indication (but different treatment protocol) and in a Phase III trial in acute myelogenous leukemia (AML) are expected to be completed by the end of this year, Stambaugh said, though the AML study calls for an 18-month treatment period.
Maxamine is a histamine type-2 receptor agonist, a potent molecule that shuts off production of free radicals, thereby protecting T cells and natural killer cells. Maxamine Therapy combines Maxamine and the cytokine interleukin-2 (IL-2). In the U.S. melanoma study, Maxamine Therapy is being compared to IL-2 treatment alone.
"It's a very clean, scientific study to show, if it succeeds, that Maxamine benefits cytokine therapy," Stambaugh said.
The patients, for the most part, will be treated at home. Initial injections will be done on an outpatient basis and then in front of a nurse or doctor. The patients then will be sent home with instructions, including a video, and a week's supply of drug.
The will inject themselves, or have someone else do it, with Maxamine and IL-2 (in separate syringes), each morning and each evening. There are a number of mechanisms in place to ensure compliance, said Kurt Gehlsen, the company's chief technical officer.
Measures In Place To Ensure At-Home Compliance
"We provide daily injection logs, so there is an accounting of drugs every week," he said. "Most importantly, these patients are very motivated, because typically they are going to die in six months or less. They don't seem to have a problem administering a regimen like this, because they want to live."
Many of the patients have home health care support, and those providers are responsible for log entries. Finally, Gehlsen said, nurses count the injection sites each week. "We're out there monitoring all these things," he said. "We haven't had a compliance issue."
The international Phase III melanoma trial involves treatment of Maxamine plus IL-2 and alpha interferon against chemotherapy. A Phase II study of Maxamine is ongoing in renal cell carcinoma, and one will begin shortly in hepatitis C, Stambaugh said.
Maxim is in discussions with prospective partners in Europe, Asia and the Pacific Rim, with the first marketing deal expected to be signed this year, Stambaugh said. Maxim will market Maxamine in the U.S.
"Maxamine is a basic discovery that modulates the immune system," he said. "We're seeing survival increases in cancer that have not been possible previously."
Gehlsen expects that cancer, like HIV, will best be treated with combination therapy, and Maxamine may be central to that approach.
The news about the Phase III trial's enrollment was expected to be disclosed today. Maxim's stock (AMEX:MMP) closed Friday at $12.25, down $0.125.