~Written by Kate Lee, MPH (Contact: kate@recombine.com)
Sanofi-Pasteur's Dengvaxia has been approved for the prevention of the four subtypes of dengue in children over 9 years old and adults under 45 years old. Photo Credit: European Pharmaceutical Review
Infectious and chronic diseases are some of the top priorities in global health. Abundant funding, both from the government and private sector, is poured into therapeutics research to help decrease morbidity and mortality from both types of diseases. For example, recent news has highlighted two promising therapies with the potential to alleviate the global burden of two diseases: dengue fever, an infectious disease, and glioblastoma, a chronic disease.
After 20 years of research, Sanofi, a French pharmaceutical company, developed Dengvaxia, a vaccine to prevent dengue. Mexico is the first country to approve the vaccine for use in children over the age of nine and adults under the age of 45. A clinical trial last year found the vaccine to have an effectiveness of 60.8% against four strains of the virus[1]. Sanofi bypassed European and US regulations and sought regulatory approval for Dengvaxia in dengue-endemic countries. According to their press release, the vaccine, “will be priced at a fair, affordable, equitable, and sustainable price... and may be distributed for free in certain countries”[2].
Dengue is a febrile viral illness that is spread via the bite of an infected mosquito, and is endemic to tropical and sub-tropical climates. According to the World Health Organization (WHO), about 400 million people globally are infected with the dengue virus each year. Prevention has been limited to effective mosquito control and appropriate medical care[3]. These measures are often either ineffectively implemented, or there are limited, or no available medical resources in the community. Dengvaxia has the potential to reduce the burden of dengue, especially in developing countries that are particularly hard-hit with the disease. Future research could be directed towards making the vaccine more effective in children, as severe forms of dengue are the leading cause of illness and death in children in Asian and Latin American countries[3].
As one tropical virus is being prevented, another virus is being used to combat brain cancer. Researchers at Harvard and Yale have teamed up to use vesicular stomatitis virus (VSV) and Lassa virus, to search for and destroy cancer cells in mice[4]. Lassa is a febrile illness, usually transmitted by rodents, and is endemic to tropical and subtropical regions of the world[5]. VSV has been studied for many years and is generally effective in killing cancer cells; it becomes deadly to the patient when it reaches the brain[4,6]. Interestingly, including Lassa virus appears to make VSV safe for cancer therapy in the brain.
Researchers created a Lassa-VSV chimera, an organism that includes the genetic codes of two different organisms, to target glioma, one of the deadliest forms of brain cancer, which accounts for more than 80% of primary malignant brain tumors[7]. Glioblastoma is the most common form of glioma and is associated with poor survival, making this chimeric treatment a potential life saver for many patients. The next step in the treatment development process is primate research to evaluate safety. This is still a long way from the initiation of human trials, and eventual market, but promising nevertheless, for the millions of people globally who are affected by brain cancer.
Dengvaxia and the Lassa-VSV chimera represent recent advancements in therapeutics with potentially significant global impact for brain cancer and dengue respectively - diseases that affect populations in many nations.
References:
1. Sanofi's Dengvaxia, World's First Dengue Vaccine, Approved For Use In Mexico. International Business Times. http://www.ibtimes.com/sanofis-dengvaxia-worlds-first-dengue-vaccine-approved-use-mexico-2219515. Published December 10, 2015. Accessed December 20, 2015.
2. World’s First Dengue Vaccine Approved After 20 Years of Research. Bloomberg Business. http://www.bloomberg.com/news/articles/2015-12-09/world-s-first-dengue-vaccine-approved-after-20-years-of-research. Published December 9, 2015. Accessed December 20, 2015.
3. Dengue and severe dengue. World Health Organization. http://www.who.int/mediacentre/factsheets/fs117/en/. Updated May 2015. Accessed December 20, 2015.
4. Using a deadly virus to kill cancer: Scientists experiment with new treatment. The Washington Post. https://www.washingtonpost.com/national/health-science/using-a-deadly-virus-to-kill-cancer-scientists-experiment-with-new-treatment/2015/12/07/7d30bc5a-9785-11e5-8917-653b65c809eb_story.html. Published December 7, 2015. Accessed December 20, 2015.
5. Lassa fever. World Health Organization. http://www.who.int/mediacentre/factsheets/fs179/en/. Updated March 13, 2015. Accessed December 20, 2015.
6. Viral Therapy in Treating Patient with Liver Cancer. ClinicalTrials.gov. https://clinicaltrials.gov/ct2/show/NCT01628640. Updated July 2015. Accessed December 20, 2015.
7. Schwartzbaum J A, Fisher J L, Aldape K D, Wrensch M. Epidemiology and molecular pathology of glioma. Nature Clinical Practice Neurology (2006) 2, 494-503. doi:10.1038/ncpneuro0289