For decades, the only options for treating cancer were surgery, chemotherapy, and radiation therapy. These remain the first-line treatments for this life-threatening disease. However, a new category of treatment has emerged in the last 10–15 years, giving new hope to cancer patients: immunotherapy.
Immunotherapy represents a class of drugs designed to boost a patient's immune system to help it fight diseases that can evade the immune system's mechanisms. Cancer, which hides from our immune system by mimicking normal, healthy cells, is one of these diseases.
One of the most common and currently considered one of the most promising types of immunotherapy is checkpoint inhibitors. These antibodies expose cancer cells to T cells, a type of white blood cell. While this class of immunotherapy has broad application in the oncology world, it is not always effective and can cause serious side effects in some patients.
The development of CAR T-cell therapies
In recent years, another class of immunotherapy has emerged: CAR T cells. This type of treatment was nominated for 2018 years Advance of the Year vid ASCO (American Society of Clinical Oncology). CAR T therapies involve extracting blood from the patient and genetically modifying the T cells. This modification causes the immune cells to express a chimeric antigen receptor (CAR), which is designed to recognize and bind to the specific cancer cells found inside the patient. The modified T cells are then returned to the patient's bloodstream where they can actively seek out and destroy cancer cells.
This personalized approach has shown remarkable results in clinical trials, in which many patients have achieved complete disease remission. The first CAR T-cell therapies received FDA approval in 2017: Novartis Kymriah and Gilead Sciences Yescarta, both for the treatment of B-cell lymphoma. Since then, four new approvals have followed. The approved treatments target a range of different forms of blood cancer.
An excellent example of success in CAR T in the Nordics
According to a article which was published at the turn of the year in Sydsvenskan was Skåne University Hospital (SUS) was the first in the Nordic region to implement CAR T as part of the treatment for cancer patients in 2020. Since then, more than 20 patients with various types of blood cancer, including lymphoma, have undergone CAR T treatment at SUS.
In a statement to Sydsvenskan said the professor Mats Jerkeman, who is a senior physician at the SUS oncology department, that about half of the patients no longer show any traces of the disease. Although there is still room for improvement, these results represent a big step in the right direction according to Professor Jerkeman. He believes that these patients would have had a significantly worse prognosis without these treatments.
High costs are a major limitation for CAR T
The CAR T therapies that have reached market approval so far have a strong safety profile. But even though CAR T treatments are promising, cost is a major limitation. According to Sydsvenskan, these treatments can cost several million kronor per patient, which means that they are currently seen as a last resort. The high cost also increases the waiting time for approval for each individual patient. This exposes patients with rapidly spreading disease to risks.
However, the high cost can be weighed against the prospect of long-term remission. Novartis' Kymriah, a single-agent treatment for acute lymphoblastic B-cell leukemia, is an example. The drug has shown a remission rate of 83 percent after three months in patients who do not respond to current standard treatments. This could not only lead to less suffering for patients, but also to a reduced overall burden on society.
For this reason, CAR T-cell therapies remain one of the most promising cancer treatments, which also means that the market potential is significant. In fact, CAR T-cell therapies, according to a report from Pharmaceutical Technology, is one of the fastest growing and potentially most profitable therapeutic areas in oncology. The report shows a market size expected to reach USD 25 billion by 2028. The area is also expected to grow at a CAGR of over 47 percent during the forecast period.
Finding ways to boost CAR molecules
One thing is certain – CAR T therapies have the potential to have a significant impact in the field of oncology, even more than they have had to date. Researchers are continuously striving to improve CAR T technology and to find new and better ways to weaponize CAR molecules to make them bind to cancer cells more specifically and effectively.
A good example is Elicera Therapeutics – currently the only biotechnology company in Sweden developing CAR T-cell candidates. Elicera's work is based on research conducted by Professor Magnus Essand and his team at Uppsala UniversityThe company is expected to enter a clinical trial with one of its candidates – ELC-301 – this year. Globally, many different biotech companies are developing a total of several hundred CAR T-cell therapies. With continued research and development, this emerging technology may be the answer cancer patients have been waiting for.