Ailsa Craig & Marek Poszepczynski, portfolio managers of the International Biotechnology Trust
Not only is a cancer diagnosis no longer a guaranteed death sentence, it does not always lead to a toxic chemotherapy regime. Breakthrough scientific developments have created targeted therapies to address the challenging disease, with particular success treating breast and lung cancer. The companies developing these revolutionary new treatments have prolonged life expectancy and reduced patient suffering, while also alleviating the burden on the healthcare system.
However, significant further investment is required to enable these cutting-edge businesses to broaden their reach. Demographic trends threaten a huge growth in cancer cases in the coming decades, and many areas of the disease remain unaddressed.
The treatment of breast cancer changed when the first targeted therapy, Herceptin, was introduced in the 1990s by Genentech, which is now a subsidiary of the Swiss group Roche. Instead of killing all cells in the process of replicating their DNA and dividing to form two new cells – the approach taken by traditional chemotherapy – targeted therapies only attack cancerous cells.
Targeted therapies are possible because oncologists no longer think of cancer as a single disease. For example, breast cancer is now divided into three major subsets – patients that are HER2-positive, hormone receptor-positive, and those that are ‘triple negative’. The initial approval of Herceptin was for patients with metastatic HER2+, after data showed a 20% reduction in mortality compared to chemotherapy alone. Herceptin is now used in earlier stage patients, where the five-year survival rate is now 90%.
Increased research and clinical successes have since led to at least 14 new targeted breast cancer drugs being launched on the market, with three approved only last year. Dozens more are in clinical trials and hundreds in initial development. One of the most recently launched targeted therapies to treat breast cancer is Gilead’s (IBT portfolio company) Trodelvy, developed for breast cancer patients whose tumours are triple negative and have historically seen few successful therapies.
Certain lung cancer patients have also seen survival rates improve. Lung cancer is the leading cause of cancer-related death globally, with 1.4 million dying each year. Chemotherapy has little impact on these patients, with a five-year survival rate of only 5-10%. However, targeted therapies for this disease started to emerge just over a decade ago and there are now nine such drugs, three of which have been approved since May of this year.
The genetic picture is more complex for lung cancer than it is for breast cancer. Non-small cell lung cancer (NSCLC) accounts for 85% of all lung cancers, and 17 different genetic mutations have been identified for this disease. Lung cancer sufferers with the EGFR and the ALK mutations have benefited from the launch of targeted therapies. In addition, Amgen has just launched a targeted therapy against the KRAS mutation, which makes up 10-15% of lung cancer patients, while Mirati Therapeutics is set to launch its version of the drug in the coming year. Both companies are holdings within International Biotechnology Trust (IBT).
No room for complacency
While the development of targeted therapies has had a significant positive impact, there is room for improvement. For instance, targeted lung cancer therapies lead many patients to develop additional mutations, which can then cause resistance to therapy.
With better understanding of the tumour micro-environment and scientific advances, we expect an increase in the personalisation of treatment for these and other tumours leading to improved survival and quality of life. This involves patients being screened for mutations and sub-type of tumour. The most appropriate treatment can then be selected rather than a ‘one size fits all’ approach which is the case with chemotherapy.
In addition, other forms of cancer such as liver and pancreatic cancer are still being treated with traditional chemotherapy, as effective targeted therapies for these diseases have yet to be developed. Further research is needed in these areas and there are hundreds of pipeline programs being run by both pharma and biotech companies aiming to address these unmet medical needs.
The ageing of populations across the world is another concern, with the number of older persons projected to double from 2019’s total to 1.5 billion by 2050. This could cause the incidence of cancers to increase dramatically over the coming decades, putting further pressure on society to develop more effective therapies.
Ultimately, much more innovation is needed to combat these issues. Our investments into companies operating in these areas will enable them to continue the development of targeted therapies, which will, in time, have a significant impact on this large unmet need.