Melanoma treatments
In an international trial of 945 patients, 58% of the candidates found that their cancer had stopped advancing after they were given a combination treatment of immunotherapy drugs Ipilimumab and Nivolumab.
How cancer hides
Studies have consistently shown that the human body is equipped and able to fight cancer, having the ability to destroy cancer cells as they develop. Unfortunately some cancers are able to cloak or hide from the human immune system, avoiding the body's natural defences all together.
Cancer cells produce a protein called PD-L1 which in effect switches off the body's ability to fight back or attack the unhealthy cells, effectively hiding the cancer from the natural defences our bodies.
How the drugs work - Checkpoint Inhibitors
Immune checkpoint inhibitors have provided a promising avenue for clinical research.
Extract from Cancerresearch.org:
"Checkpoint inhibitors work by targeting molecules that serve as checks and balances in the regulation of immune responses. By blocking inhibitory molecules or, alternatively, activating stimulatory molecules, these treatments are designed to unleash or enhance pre-existing anti-cancer immune responses."
Ipilimumab has been at the vanguard of this new immunotherapy approach. It was the first treatment ever shown to extend survival in patients with metastatic melanoma and was approved for that indication in 2011. Based on promising results from a phase II trial, it is now being tested in phase III trials
Nivolumab has been shown to remove cancer's ability to cloak or hide itself from our immune system, by prohibiting it from creating PD-L1, giving the body the chance to fight back and destroy cancer cells. It was already approved by the FDA in March 2015 for the treatment of cancers that have failed chemotherapy. Nivolumab is still being tested in clinical trials for other indications.
Lung Cancer
In particular, Nivolumab, has been found to be effective in studies of lung cancer. The results from 582 patients were described as "giving real hope".
It was shown that people receiving the standard therapy lived for another 9.4 months whereas those that received Nivolumab went on to live an average of 12.2. In some exceptional cases patients were recorded to live up to another 19.4 months.
The data was presented by the pharmaceutical company Bristol-Myers Squibb.
Lead researcher Dr Luis Paz-Ares, from the Hospital Universitario Doce de Octubre in Madrid, Spain, was quoted as saying: "The results mark a milestone in the development of new treatment options for lung cancer."
"Nivolumab is the first PD-1 inhibitor to show a significant improvement in overall survival in a phase III trial in non-squamous non-small cell lung cancer."
Other companies are now assessing similar drugs. Dr Martin Forster, from the University College London Cancer Institute, is trialling some of them.
He told the BBC: "It's really exciting; I think these drugs will be a paradigm shift in how we treat lung cancer. After chemotherapy failed, current survival rates were dire. But in those that respond [to immunotherapy] there seems to be very prolonged disease control, I think it's a huge shift in lung cancer and for patients it's going to be dramatic".
Side effects
It’s still uncertain as to who will benefit from long term immunotherapy treatments and what the consequences of modifying the immune system are.
Dr Alan Worsley, Cancer Research UK's senior science information officer, said:
"Together these drugs could release the brakes on the immune system while blocking cancer's ability to hide from it, but combining these treatments also increases the likelihood of potentially quite severe side effects."
Mesothelioma
Although there is no mention of these drugs being particularly effective against mesothelioma, we hope that in time this disease will be eradicated.
Approaches to immunotherapy for mesothelioma have shown real promise and with advances in therapeutic vaccines such as the WT1 antigen and TroVax®, we are moving closer to a cure that one day, will save lives.