Treatment with therapeutic cancer vaccines, oriented HER2, had a clinical benefit to several patients with metastatic HER2-positive cancer who have not previously received a therapeutic treatment with HER2, according to clinical trial phase I, presented at the Fourth International Conference on Cancer immunotherapy: Transfer science in survival, carried out on 30 September.
Among the 11 patients with the assessment, which received a lower dose of the vaccine, six (54 percent) had clinical benefit. One patient with ovarian cancer had a complete response, which lasted 89 weeks, one patient with gastroesophageal cancer had a partial response that lasted 16 weeks, and four patients (two with colon cancer, one with prostate cancer and one with ovarian cancer ) did not have the results.
"Immunotherapy causes exquisite specificity of the immune system to destroy cancer, and some types can have potentially fewer side effects than traditional chemotherapy," - said Jay A. Berzofski, MD, chief physician of the vaccine department at the Center for Cancer Research, National Cancer Institute National institutes of health, Bethesda, Maryland. "We use the vaccine approach for the immune response to of HER2, which is at high levels and stimulates the growth of several types of cancer, including breast cancer, ovarian, lung, colorectal and gastroesophageal cancer.
"Our results show that we have a very promising vaccine for HER2-overexpressing cancers," - continued Berzofsky. "We hope that one day the vaccine will provide a new treatment option for patients with these cancers."
Vaccines patients individually configured Bertsofskim and his colleagues using their own immune cells isolated from their blood. In the laboratory, the immune cells derived from blood, modified in several ways. The final product, which is introduced intradermally (between skin layers) obtained from the organism contains dendritic cells genetically modified adenovirus for HER2 protein parts.
Preclinical studies previously published in the journal AACR Cancer Research, showed that this type of vaccine can destroy large established tumors as well as metastases to the lungs in mice.
In dose escalation phase I clinical trials, patients were administered the vaccine at weeks 0, 4, 8, 16 and 24 after receiving the study. Among the six patients who received the lowest dose of the vaccine, 5 million dendritic cells per injection, clinical benefit was observed. Among the 11 patients who received an injection of 10 million or 20 million dendritic cells in six patients had clinical benefit.
Adverse reactions were mainly reactions at the injection site, which did not require treatment. Cardiotoxicity were observed.
"Based on the current data on the safety and clinical benefits of the vaccine dose was increased to 40 million dendritic cells per injection, and the study was open to patients who previously were treated with therapeutic preparations of HER2, including patients with breast cancer," said Bertsofsky.
"Moving forward, we would like to find out whether we can increase the share of people who are benefiting from the treatment of the vaccine by combining it with inhibitor therapy control points", - he added.
According Bertsofskogo, restriction of basic scientific research is that it is relatively small phase I clinical trials without placebo control. However, this approach is promising enough to guarantee additional tests.