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A Cancer Vaccine

A promising new treatment is being tested in Israel

We are all familiar with vaccines to prevent TB, whooping cough and other major contagious diseases. But now there is a new vaccine that has been developed and is being tested in Israel that might be the answer to eventually treating those who have cancer, not preventing it. The therapeutic vaccine deals with sick patients and tries to harness their immune systems to destroy the cancer cells.
  
The peptide vaccine is called ImMucin™and it was developed by Dr. Lior Carmon who founded his company named Vaxil in 2006. ImMucin™ is in Phase I/II trials to treat cancer. Dr. Carmon is a biotechnology entrepreneur with a doctorate in immunology from the Weizmann Institute of Science.
  
ImMucin™ is based on a unique sequence in the MUC1 tumor-associated antigen which is found in 90 percent of all tumors, which makes it of great interest to the one out of two or three of us who will eventually get cancer in our lifetimes. The MUC1 gene was first discovered in breast cancer in the 1980s. MUCI is present in most solid tumors and blood cancers. ImMucin™ “trains” the cancer patient’s immune system to identify and destroy the cancer cells where the MUC1 is present.
  
The therapeutic vaccine is being tested on a small number of patients with multiple myeloma. Vaxil expects to test 15 patients at the Hadassah University Medical Center in Jerusalem. An interum report has been filed with the regulatory information related to seven patients who had finished the treatment with ImMucin™. Three of the seven patients had a complete response to the treatment, as reported within a month of treatment. There were no side effects to ImMucin™ beyond the first day and there were responses reported in all the patients (as observed in CD4+ and CD8+ T cells), including those who had only 2-4 doses of the vaccine (out of 12 possible doses).
  
It is hoped that the ImMucin™ vaccine could be given to patients on a regular basis to keep the cancer from recurring, without the side effects and limits that normally accompany chemotherapy. Traditional chemotherapy drugs usually stop becoming effective after a time too—a process that is called the “tumor escape mechanism.” ImMucin™trains the immune system to attack the cells that have MUC1.
 
Although the ImMucin™vaccine has been given to patients in a small trial for a very short time, Vaxil is optimistic. Others in the medical field are not commenting until there are results from long-term  trials that find that ImMucin™ extends survival or that the vaccine extends a progression-free quality of life that surpasses other treatments such as novel agents that are already being used successfully by cancer patients.
   
For patients who have large solid tumors in an advanced stage, doctors say that surgery or traditional chemotherapy might be needed to shrink the tumor before treatment with injections of ImMucin™.
  
Patients enrolled in the ImMucin™ trial receive 6 biweekly 100 microgram injections of ImMucin™ and recombinant human granulocyte-monocyte colony stimulating factor (rhGMCSF). If there is not an observed response after 6 injections, the dose of ImMucin™ is increased to 250 micrograms for 6 more injections.

Other Vaccine Trials
According to The Atlantic, Dr. Jeffrey Schlom, head of the Immunotherapeutics Group at the Center for Cancer Research at the National Cancer Institute, said guardingly, “There have clearly been failures of vaccines targeting MUC1, but that doesn’t mean newer vaccines won’t do it better.” The Atlantic writes that a vaccine called Stimuvax® for lung cancer should finish testing next year. There are currently around 30 cancer vaccines targeting MUC1 in clinical trials. Few vaccines have generated as much press as ImMucin™. Physicians are waiting for results of these vaccine trials to be published in peer-reviewed journals.

On the Horizon
Dr. Carmon’s company,Vaxil BioTherapeutics, merged with Sheldonco Ltd, a “shell company,” in April. Sheldonco Ltd is traded on the Tel Aviv Stock Exchange (TASE:SLDC) and the companies are expected to finish the closing paperwork in the next few months. Provided the vaccine succeeds in large scale clinical trials, it is hoped that ImMucin™ could become available to patients in about 6 years.
  
On another note, according to MSNBC, the FDA is supporting a proposal to hopefully be passed by Congress this summer that would speed up U.S. approval of “breakthrough” drugs for treating life-threatening diseases. Many are hoping that the U.S. will catch up to the Europeans in bringing new treatments to patients. 

Published: June 10, 2012
Issue: Summer 2012 Issue