wikipedia | CimaVax-EGF is the first therapeutic cancer vaccine developed to target non-small-cell lung carcinoma (NSCLC), the most common form of lung cancer. The vaccine was the result of a 25-year research project at Cuba’s Center of Molecular Immunology.[1][2]
The product has gone through 2 trial phases in Cuba and is currently in
the process of going through a third trial, and there are agreements in
place to test it in the United States (at Roswell Park Cancer Institute, subject to approval of a New Drug Application by the U.S. Food and Drug Administration), Japan, and some European countries.[3] It is currently only available in Cuba.
CimaVax is an active vaccine in which patients are immunized with epidermal growth factor (EGF), thus raising antibodies targeting EGF itself. The product is also formulated with the Neisseria meningitidis outer protein P64k and Montanide ISA 51 as an adjuvant to potentiate the immune response.[4] The epidermal growth factor receptor
(EGFR) is hijacked by many types of cancer, including cancers of the
lung, colon, kidney, and head and neck. By raising antibodies against
EGF, which is EGFR's major ligand,
the concentrations of EGF in the blood are reduced. Thus CimaVax does
not target the cancer cells directly, but is expected to work against
these cancers by denying the cancers the growth stimulus they require.[4][5] For this reason, the Roswell Park group thinks that it may prove most useful as a preventive vaccine rather than as a cancer therapy per se.[3]
Early trials showed a statistical trend towards an improved survival rate amongst vaccinated test subjects.[4][6]
A direct correlation between the level of antibodies that a vaccinated
patient raises against EGF and survival has been observed in several
trials,[4] and in one of the largest trials[5] there was also an age-dependence, with only subjects under the age of 60 benefiting in terms of survival.[4] More antibodies are raised when the vaccine is formulated with Montanide ISA 51 rather than aluminum hydroxide as an adjuvant, and when patients receive a low dose of cyclophosphamide three days before vaccine administration.[4] Cyclophosphamide is thought to temporarily block the body's natural immune tolerance to EGF, thereby increasing antibody titers.[4]
CimaVax is relatively cheap to produce and store, and has low toxicity.[3] Side effects of the vaccine appear to be mild, and include chills, fever, headache, nausea.[7][4]
Researchers caution that the early results to date have been in
relatively small, early-stage trials with patients that were carefully
selected based on predefined inclusion and exclusion criteria, and given
specialized oncology care; they may therefore not be representative of
most patients who might benefit from the vaccine.[4]
It has been urged that CimaVax be tested in patients with earlier-stage
NSCLC cancer and in patients who are not candidates for chemotherapy, and that research be conducted to determine which subgroups of NSCLC patients do and don't respond the vaccine.[4]
It has also been suggested that CimaVax may also be effective in other
types of cancer that are dependent on EGF/EGFR, including many cases of prostate cancer.[4]
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