Researchers hope the vaccine they soon will begin testing in humans will prevent or delay the recurrence of some cancers.
Patients with pleural mesothelioma will be among the first to receive the H1299 lysate vaccine with an Iscomatrix adjuvant. The vaccine is a form of immunotherapy designed to trigger the body’s immune system into preventing new cancer growth.
The National Institutes of Health(NIH) will begin conducting the three-year trial in September. It’s designed for patients whom recently completed standard treatments, including surgery, chemotherapy or radiation, and whom have little or no residual disease at the start.
The NIH, in Bethesda, Maryland, already is conducting a handful of other clinical trials involving mesothelioma and immunotherapy, but researchers sound particularly enthused about this one.
“We’re very excited about the potential of this trial,” David Schrump, M.D., senior investigator and surgical chief at the NIH, told Asbestos.com. “We’d very much like to have some mesothelioma patients involved. It’s a unique opportunity. We’ve had considerable interest already.”
The lysate vaccine with Iscomatrix, not previously used in humans, will be tested on patients with lung and esophageal cancers, along with mesothelioma and certain other thoracic sarcomas.
The trial will measure the response rate of the vaccine given alone, in contrast to the vaccine given in conjunction with metronomic cyclosphosphamide, a chemotherapy drug, and celecoxib, an anti-inflammatory drug.
Providing a patient with a genetically engineered protein molecule, or antigen, derived from his own tumor cells, has been successful in causing an immune response with certain cancers.
Doctors at the NIH have shown an ability to successfully harvest mesothelioma tumor cell lines to help create the vaccine. Since mesothelioma almost always returns after even the best multidisciplinary treatment, researchers are hoping the drug will show some promise.
Regulatory issues temporarily delayed the trial originally slated to start earlier this year. The NIH is hoping to recruit an estimated 60 patients for the randomized trial. Half of the trial participants will receive the vaccine alone, while the others will receive the vaccine with chemotherapy.
The NIH will provide patients the vaccine once a month.
Officials will record immunologic and systemic toxicities to the vaccine and also monitor patients with routine scans until disease recurrence.
Clinical trials often have become a patient’s best hope for finding the newest and most advanced therapy, especially for a rare disease like mesothelioma, where treatment options are limited. There is no cure for this disease and the typical life expectancy after diagnosis is only 9-18 months.
Medical expenses related to clinical trials at the NIH are provided free of charge, an advantage that comes with a federally subsidized program. Out of town participants and their families, often receive free or drastically reduced lodging, too.
The NIH has almost 50 ongoing studies involving pleural mesothelioma, the cancer caused almost exclusively by exposure to asbestos. Several of those clinical trials are testing immunotherapy agents that help a body’s own immune system fight the disease.
Many experts believe immunotherapy is the future of cancer treatment.
Schrump worked in another tumor cell vaccine (K562) clinical trial at the NIH involving multiple malignancies, but testing it with mesothelioma has not been completely successful.
Although extracting tumor cell lines was successful, the disease returned before patients could be vaccinated, eliminating them from the trial. The vaccine worked well with other malignancies.
“It’s critical that patients be involved in clinical trials,” Schrump advised. “It’s the only way to make advancements with a disease like mesothelioma.”