The new treatment, which will bring hope to hundreds of thousands of people in Britain with terminal conditions, involves the combination of two different types of drug that 'reboot' the immune system.
|Scooped by Graham Player Ph.D.|
A new treatment for skin cancer which combines two drugs that help to ‘reboot’ the immune system is showing positive encouraging effects in seriously ill melanoma patients.
One of the drugs, ipilimumab, was approved by the FDA in March 2011 to treat patients with late-stage melanoma that has spread or cannot be removed by surgery. According to research presented to the European congress in Amsterdam just a few days ago, 17% of patients are cured by this drug alone.
Another class of immunotherapy drugs known as anti- PD1 drugs has been shown to block activity of the programmed death 1 (PD-1) molecule, an immune checkpoint receptor found on T cells. T cells fight infections in our bodies and also facilitate the body’s attack on tumors. The PD-1 molecule on T cells interacts with another molecule, the programmed death 1 ligand (PD-L1) that fits with PD-1 like a lock and key. This interaction helps to modulate the immune response of T cells to various stimuli, including infections. PD-L1 is found on cells throughout the body, but tumor cells can also express PD-L1, resulting in a dampened response of the immune system to the tumor. Anti-PD1 antibodies block the interaction between PD1 and PD-L1 to boost T-cell activity in response to tumors.
Initial trials have shown that combining ipilimumab with anti-PD1 drugs produces ‘spectacular levels of tumor shrinkage’ according to Dr James Larkin, of the Royal Marsden Hospital in London. Initial trial results presented earlier this year showed that tumors shrank by more than half in 11% of patients put on ipilimumab, in 41% put on anti-PD1s – but in 53% of those given both.