September 11, 2013
According to the U.S. Centers for Disease Control and Prevention (CDC), ten infectious diseases have been at least 90 percent eradicated in the United States, including smallpox, measles, and polio for which vaccines have been recommended for decades. But vaccines are not only for preventing infectious diseases, some immunotherapeutic vaccines help the body fight a range of illnesses by activating the immune system to recognize and attack disease.
America’s biopharmaceutical research companies are developing more than 270 vaccines to prevent and treat disease, according to a new report by the Pharmaceutical Research and Manufacturers of America (PhRMA). The vaccines – all either currently being tested in clinical trials or under review by the Food and Drug Administration – include 137 for infectious diseases, 99 for cancers, 15 for allergies, and 10 for neurological disorders.
Vaccines currently in development include:
- A therapeutic vaccine for HIV infection intended to delay disease progression.
- A monoclonal antibody vaccine that targets both pandemic and seasonal flu.
- A genetically-modified vaccine designed for the treatment of pancreatic cancer.
- An irradiated vaccine for protection against malaria.
Currently, there are 204 active clinical trials for vaccines in the U.S., including 107 that have not yet started recruiting patients or are just now seeking volunteers to participate. These trials, in combination with the promising new scientific approaches researchers are using, build on the successful history of vaccination against infectious diseases. Advances in areas such as genomics are enabling researchers to develop therapeutic vaccines, including immunotherapies for some types of cancer and other diseases. In addition, vaccines today are not limited to injectables; new delivery methods include nasal sprays, powders and transdermal applications, among others.
Malaria—A malaria vaccine in development has shown to be 100 percent effective in early clinical trials in preventing the transmission of the disease from infected mosquitoes to humans. The vaccine builds on initial knowledge gained in the 1970s, where researchers demonstrated that long-term protection against malaria was possible when volunteers received thousands of bites from radiated infected mosquitoes. The vaccine in development uses a weakened form of the whole sporozoite, a life-stage of the parasite Plasmodium falciparnum that causes malaria. This weakened form of the parasite is enough to cause an immune response, but not cause the disease, thus leading to protection against any future malarial bite infection.
Cervical Cancer—A live, attenuated Listeria monocytogenes (LM)-based immunotherapy is in development for the treatment of women who already have cervical cancer as a result of infection by the human papillomavirus (HPV). The vaccine targets the HPV gene E7, which is responsible for the transformation of HPV-infected cells into dysplastic or malignant tissue. The vaccine is engineered to secrete a fusion protein that instructs the body’s immune system to destroy the tumors.
HIV Infection—A therapeutic vaccine in development is targeting the low-mutating (conserved) parts from the protein p24 of the HIV virus. The vaccine consists of four peptides that are modified to increase the immune response against the conserved parts of the p24 protein. A sustained immune response against the p24 protein has shown to be associated with delayed disease progression.
Influenza—A monoclonal antibody (mAb) vaccine in development targets both pandemic and severe seasonal influenza A virus infections. The mAb vaccine, made from recombinant human antibodies from human B-cell cultures, specifically targets the M2 protein of the virus, which is essential for the influenza virus to function normally.
Pancreatic Cancer—A potential treatment for pancreatic cancer is a combination of two therapeutic vaccines. The treatment combines a Listeria-based vaccine that has been engineered to express the tumor-associated antigen mesothelin and allogeneic pancreatic cancer cells that are genetically-modified to secrete the immune-stimulant, granulocyte-macrophage colony stimulating factor (GM-CSF). The cells are irradiated to prevent further cell growth although they stay metabolically active. Sequential administration of the vaccines in animal studies have demonstrated enhanced tumor-specific T-cell and anti-tumor responses.
Smoking Cessation—One in a new class of targeted vaccines in development induces an antigen-specific immune activation for smoking cessation and relapse prevention. It is made from biocompatible and biodegradable materials and is a fully synthetic nanoparticle vaccine engineered to mimic the properties of natural pathogens to elicit an immune response.