Brain, Breast, and Liver Cancers All Respond to Immunotherapy

June 2012, Vol 3, No 4

Chicago, IL—Immunotherapy is nontoxic, tumor-specific, long-term therapy with a long-term memory. The expectation is that once the patient has been treated with immunotherapy, the therapeutic effect will remain and safeguard the patient for life by provoking the immune system to attack any return of the cancer.

There is progress in at least 4 areas: pediatric brain tumors, breast cancer, hepatocellular carcinoma, and generally advanced cancers, according to 4 current studies described at the 2012 American Association for Cancer Research meeting.

“Do not be discouraged when you hear about moderate success,” said moderator Olivera J. Finn, PhD, Chairman of the Department of Immunology at the University of Pittsburgh. “In the setting of advanced cancer, moderate success is great news.”

Brain Tumors

Survival has been extended in children with brain tumors, according to interim results of a pilot study of 22 patients with high-risk gliomas treated with peptide-based vaccine therapy. Their prognosis would typically be dismal, said Ian F. Pollack, MD, Chief of Pediatric Neurosurgery at Chil - dren’s Hospital of Pittsburgh, and Walter Dandy Professor of Neuro - surgery at the University of Pittsburgh School of Medicine. Typical overall survival is barely 35%.

These patients were treated with glioma-associated antigen (GAA)-based immunotherapy using a “cocktail” of novel GAA peptides.

So far, 19 of the 22 patients have had stable disease or have at least responded through 2 vaccine cycles. There have been 7 cases of pseudoprogression. Of all patients, 3 had partial response, 1 had a mixed response, and 1 had prolonged disease-free status postresection. Of 11 patients with adequate follow-up, 8 have survived beyond the historical medium of 10.5- month survival.

Breast Cancer

Diane F. Hale, MD, a research resident in general surgery at Brooke Army Medical Center, Fort Sam, Houston, TX, described very encouraging immune responses from pa - tients with breast cancer treated in a phase 2 trial of the novel AE37 HER2 peptide vaccine. The trial compares AE37 with granulocyte-macrophage colony-stimulating factor (GM-CSF) versus GM-CSF alone.

“The goal of the vaccine is to prime the immune system to recognize and attack the HER2 protein that is found in breast cancer, and thus, if or when the patient has a recurrence, their immune system will recognize it and then take action,” said Dr Hale.

The AE37 vaccine combines 2 proteins to target HER2. Trastuzumab (Herceptin) also targets HER2, but it is available to only approximately 20% of patients in the adjuvant setting. AE37 can be used in 50% to 60% of patients expressing HER2.

This small, randomized, controlled trial has already proved AE37 to be effective in stimulating the host immune system to recognize and kill cancer cells in the adjuvant setting. A benefit was demonstrated for all 217 patients at 22 months of followup, and a much greater benefit was shown for patients with low expression of HER2.

Hepatocellular Carcinoma

Ignacio Melero, MD, PhD, Department of Oncology and Professor and Senior Investigator in El Centro de Investigacion Medica Aplicada at the Universidad de Navarra, Pamplona, Spain, described a study of 21 patients treated with the humanized immunoglobulin G2 monoclonal antibody tremelimumab (CP- 675,206). Therapy produced an intense and persistent antiviral effect in more than 50% of the patients, Dr Melero reported.

Francesco Recchia, MD, Director of Oncology at the Civilian Hospital in Avezzano, Italy, described a phase 2 study of maintenance immunotherapy with a combination of low-dose interleukin-2 and 13-cis retinoic acid in advanced cancer, which he said has produced a sustained improvement on natural killer cells, and a decrease of vascular endothelial growth factor.

Related Articles