By Michael Albert, Northwestern University ’20
You would not have to look too hard to see the word “immunotherapy,” which seems to be the latest buzzword in the field of oncology. At the most basic level, immunotherapy harnesses the body’s own powerful disease fighting mechanisms and puts them to work against cancers and potential threats. The word “immunotherapy” is really an umbrella term for any treatment that bolsters or stimulates the body’s own immune system. The field grew out of one seemingly routine observation by a surgeon in the 1890s by the name of William Coley.1 Coley noticed that cancer patients eventually attaining remission often had fevers accompanying their battle. This phenomenon suggested that patients who responded most successfully to their cancer treatment were receiving some sort of unknown aid, presumably from their own bodies. The principle behind this observation has been the subject of recent breakthroughs and success stories surrounding the cancer research community as the efficacy of toxic chemotherapy drugs seems to have plateaued. Pharmaceutical giants like Roche, Amgen, and Novartis have announced billions of dollars in funding and development of the next wave of chemotherapies, some of which are just starting to hit the market now.2 Dr. Monica Guzman of Weill Cornell Medical College told The Medical Decoder: “I believe the scientific community is excited because retraining the immune system to detect tumor cells may long term benefit as the improved immune cells will not only be able to eradicate tumors, but be able to keep them away.” As Dr. Guzman alluded, these new therapies are capable of preventing relapse in certain situations, which would effectively overcome one of the greatest hurdles facing cancer research today. The sentiment behind this quote is reflected by the entire research community as the first of the newest wave of immunotherapy drugs that aim to turn the cancer community upside down.
Making waves recently is a drug called pembrolizumab, also marketed as Keytruda. This potentially revolutionary drug has shown immense potential in eradicating melanoma cells, as well as other cells across many different lineages and types of cancer. Keytruda is just one example of the new, highly-funded immunotherapy drugs hitting the market right now.3 First approved for melanoma in 2014, Keytruda has now racked up approvals for lung cancer as well as several head and neck cancers.4 The mechanism behind Keytruda, along with many other immunotherapy drugs, is an antibody that binds to a programmed cell death receptor on the surface of the cell, effectively breaking down the malignant cell’s ability to resist treatment.
While therapies like Keytruda are beginning to gain traction and display reliable results, they are very much in the pipeline and still have much to prove. Keytruda and its counterparts exist primarily as proof of principle, but the underlying research opens up a vast network of cell receptors that can be targeted and exploited at the benefit of the cancer patients.5 For instance, recent Phase 3 clinical trials have proven Keytruda’s ability to be more effective and less debilitating than chemotherapy in lung cancer. Immunotherapy has the potential not only to influence remission rates, but also dramatically decrease side effects. Since the drugs have little cytotoxicity-a drug’s tendency of being harmful to cells-patients taking such drugs can reject many of the traditional side effects that come with chemotherapy.6 Additionally, whereas many conventional chemotherapy drugs are only effective until remission, the mechanisms behind many inhibitors allow for their use beyond remission, which would drastically reduce the relapse rate.7 As immunotherapy established itself as a staple in modern cancer therapy, more and more people will hear about immunotherapy and its promise.
1. Grady, D., & Pollack, A. (2016, July 30). What is Immunotherapy? The Basics on These Cancer Treatments. Retrieved November 30, 2016, from http://www.nytimes.com/2016/07/31/health/what-is-immunotherapy-cancer-treatment.html?_r=0
2. Keytruda Approval History. (n.d.). Retrieved November 30, 2016, from https://www.drugs.com/history/keytruda.html
3. Kiesler, E., & Begley, M. (2016, May 10). The Future of Cancer Research: Five Reasons for Optimism. Retrieved November 30, 2016, from https://www.mskcc.org/blog/future-five-reasons-optimism
4. Merck’s Keytruda succeeds in key bladder cancer trial. (2016, October 21). Retrieved November 30, 2016, from http://www.reuters.com/article/us-merck-co-study-idUSKCN12L1BX
5. Parish, C. R. (n.d.). Cancer immunotherapy: The past, the present and the future. Retrieved November 30, 2016, from http://www.nature.com/icb/journal/v81/n2/full/icb200316a.html
6. Pietrangelo, A. (2016, October 12). The Value and Cost of Immunotherapy Cancer Treatments. Retrieved November 30, 2016, from http://www.healthline.com/health-news/value-and-cost-of-immunotherapy#3
7. Roland, D. (2016, October 20). Roche Sales Lifted by Cancer Drugs. Retrieved November 30, 2016, from http://www.wsj.com/articles/roche-sales-lifted-by-cancer-drugs-1476940985