This article is the first in a five-part series about emerging vaccines for multiple myeloma.  It provides an introduction to the concept of a myeloma vaccine.  The second article provides an introduction to the various types of vaccines that are currently under development for myeloma, the third article describes vaccines for which clinical trials have been completed, the fourth article focuses on ongoing vaccine research, and the fifth article tells the story of a patient who participated in a myeloma vaccine clinical trial.

A Search For The Cure

Multiple myeloma is the second most prevalent blood cancer in the United States. Despite advances in drug combination therapies and stem cell transplantation techniques, multiple myeloma is still considered an incurable disease (see related Beacon news).

While options for the management of myeloma continue to improve, disease relapse remains common. With the emergence of many novel therapies, developing treatments that cure myeloma is the research goal of many scientists.

One treatment strategy that has attracted attention from researchers is therapeutic vaccination, a form of “immunotherapy” that harnesses the immune system to fight and destroy cancer cells.

The goal of therapeutic vaccination is to activate cells in the immune system to recognize tumor cells as “foreign,” ultimately resulting in their destruction.

Dr. Maurizio Bendandi, a physician currently conducting myeloma vaccine research at the University of Navarra in Spain, believes that the development of a safe and effective vaccine could ultimately be used as an alternative maintenance option for myeloma patients.

Preventative Versus Therapeutic Vaccination

People are typically familiar with preventative vaccines, which as their name suggests are used to prevent a disease.  Therapeutic vaccines, however, are used to treat or cure an already existing disease.  Therapeutic vaccines are the type being studied for the treatment of multiple myeloma.

Preventative vaccines work by exposing patients to a safe form of a disease-causing agent (pathogen), most often a weakened or killed form of a virus. The immune response to the safe form of the pathogen is often enough to completely protect patients from disease caused by the active form of the pathogen years after the person receives the vaccine.

Since the late eighteenth century, preventative vaccination has forever changed medicine and its practice.  Diseases such as polio and smallpox have essentially been eradicated due to preventative vaccination.  In 2009, the FDA approved Gardasil, a vaccine against human papillomavirus, making it the first vaccine available for the prevention of cancer.

Although the development, production, and distribution of preventative vaccines exploded during the 20^th century, the development of therapeutic vaccines, which can be used to treat already existing disease, remains a challenging area of research.

Therapeutic cancer vaccines have been intensely researched for more than a decade. So far, only one has been approved for use in the United States.  Provenge (sipuleucel-T) received FDA approval in April of last year for the treatment of certain men with advanced prostate cancer.

Unlike preventative vaccination, which stimulates a protective immune response before disease occurs, therapeutic vaccination must stimulate an immune response against an already established disease, a process that has proven to be very difficult to initiate and sustain.

Pathogens differ greatly from human cells, and are therefore more easily recognized by the immune system as “foreign.”

Cancer, on the other hand, arises from mutations in human cells. When developing therapeutic vaccines for myeloma, researchers must vaccinate against components that are present in cancerous cells but not normal cells. If the vaccine component is not specific enough to the cancerous cells, the immune system may not respond at all, or it may begin to recognize normal cells as “foreign,” resulting in their destruction.

Dr. Ravi Vij, a myeloma expert and researcher from Washington University in St. Louis, said that myeloma vaccines could conceivably lengthen progression-free survival with minimal side effects.  However, he also said that there are several hurdles that must be overcome, including finding the right targets to generate the vaccine as well as making the vaccine elicit a strong enough immune response.