Immunotherapy is touted more and more as the future of cancer treatment. Big pharma is determinedly looking for alternative therapeutics beyond chemotherapy, which has not shown to provide convincing benefit with solid tumors, and immunotherapies provide a good option as we learn more about the mechanisms of action and how they impact the immune system. In a new study on multiple myeloma, immunotherapy led 70 percent of participants to produce a significant clinical response, and with 24,000 new diagnoses in America each year alone, it’s not hard to see why the industry is excited about this approach to cancer treatment. All the buzz led to the first International Cancer Immunotherapy Conference held this fall, and some analysts are even predicting that immunotherapy will constitute 60 percent of all cancer treatments by 2024.
While immunotherapy is experiencing a trajectory of interest and growth, quality clinical trial data, companion diagnostics and costs are essential factors in driving its advancement. And while the use of one’s immune system to successfully fight cancer may be as personalized as personalized treatment gets, this also ushers in a new level of complexity as scientists need to find newer, faster ways to asses immune profiles through tissue analysis.
So the question is, will immunotherapy become the mainstay for cancer treatment in the near future?
Working Through Challenges
Developing immunotherapies comes with a set of both technical and implementation challenges. Today’s portfolio includes few approved checkpoint inhibitors, and those that exist are for select indications – only for patients who have already undergone the current standard of care and were unresponsive to everything prescribed, making immunotherapy the last line of therapy. There is great potential for immunotherapy to be effectively used as first or second line treatment, when the patient’s immune system is still active and not impacted by a chemo or radiation regimen; however the challenge is identifying the patients that would make appropriate candidates so the drug can be justified in moving into first or second line.
This of course relates to the second challenge – developing companion diagnostics. Diagnostics are needed to determine the patients at highest likelihood to respond to a therapy. Tissue is at the center of CDx and cancer therapy – treatment is not administered without a proper diagnosis, which is based on analyzing a patient’s tissue samples – but currently, there are very few tissue-based diagnostics.
Part of the issue is having the ability to understand the spatial distribution of immune cells and their proximity to the tumor. The spatial relationship of immune cells within the tumor setting is of crucial importance and can only be analyzed with automated tissue analysis. At the moment, this is not something that clinical labs and scientists are used to considering as part of their testing. Secondly, the biomarkers being targeted are inducible, so if a patient has already undergone surgery or received a variety of drugs, the expression of those markers may be influenced. This means the markers used for companion diagnostics and immunotherapies must be robust enough that they won’t be altered by various external factors.
The most well-known and perhaps widely used diagnostic is HER2, which can be quite effective. However, it’s unknown how patients who don’t overexpress the HER2 protein will respond to therapy, indicating there is still a great need to develop more robust tissue-based assays to effectively identify the appropriate patients for treatment.
What’s to Come
Some cancer centers would like to administer immunotherapies 100 percent of the time in the near future, but that goal is unreasonable. While checkpoint inhibitors are very effective for certain diseases, they will never be the magic bullet or sole weapon targeting every type of cancer.
That said, we will see much more in immunotherapy over the next year. The big players in the field are pushing for advancements and placing a large focus on immunotherapy research. Roche recently announced it’s hiring an additional 30 cancer immunotherapy experts in its innovation center, and drug companies are researching immune approaches for various indications, both small and large.
Over time the immunotherapy space will consolidate. Checkpoint inhibitors will most likely show the most benefit in combination therapies, either with other checkpoint inhibitors or with conventional therapies such as chemotherapy. Long term, more immunotherapies will be approved and used, but they will come in parallel with other therapies and often be used in combination.
There is significant attention on immunotherapy now, and the analysts may have it right when they say 60 percent of all cancer treatments will be immunotherapies by 2024. There is strong activity in the space and it will continue to grow. However, there are roadblocks to growth that can’t be ignored.
In addition to the challenges around developing companion diagnostics and identifying the right patient cohort, cost is a significant prohibitive factor. Biologics are inherently more expensive than chemotherapy, and we as a community – patients, treatment centers, drug companies and payers – cannot afford to pay $10,000 per year for a biologic treatment for every patient. Chemotherapy is much cheaper, so thousands of patients can be treated and provided a good standard of care. Thus, immunotherapy may not be as quickly implemented into the standard of care as some may think. In the early stages, it may only be integrated by specialized hospitals and treatment centers or university settings versus being available to the broader population.
The questions for immunotherapy will be: can we identify the right patient to treat, is it endurable for the patient, does it provide significant benefit, and is it sustainable from a cost perspective? Without significant long-term benefit, it will be hard to convince patients, payers and the government to pay for these therapies. More trials need to be conducted to answer these questions and enable immunotherapies to reach their true potential and that 60 percent prediction.
About the Author
Dr. Huss is Chief Medical Officer of Definiens and has more than 20 years of training and experience in histopathology and cancer research. Prior to joining Definiens, he served as Global Head of Histopathology and Tissue Biomarkers at Roche Diagnostics. He also co-founded the biotech company APCETH.
Ralf Huss, MD, Chief Medical Officer, Definiens