The lives of thousands of Brits living with advanced Merkel cell skin cancer are set to be transformed thanks to a groundbreaking new treatment approved by the Medicines and Healthcare products Regulatory Agency (MHRA). As of today, 6th July 2026, Retifanlimab (ZYNYZ) becomes the first dedicated treatment option for adults whose cancer has spread or recurred and cannot be treated with surgery or radiotherapy.
Merkel cell carcinoma (MCC) is a rare and aggressive form of skin cancer that originates from Merkel cells – tiny neuroendocrine cells in the top layer of the skin. Its ability to rapidly spread has made it a formidable foe for patients and clinicians alike. Finding effective treatments for advanced stages has been a significant challenge, but today's approval offers new hope.
Retifanlimab works by harnessing the power of immunotherapy – boosting the body's natural immune response against cancer cells. It specifically targets and blocks a pathway that cancer cells often exploit to evade detection by the immune system. This allows the immune cells to more easily identify and destroy the cancerous cells, providing a new approach to combating MCC.
The treatment involves administering Retifanlimab via an intravenous infusion over approximately 30 minutes. Data from clinical trials involving 101 adults with advanced MCC who had not received prior treatment for their advanced disease show promising results. An impressive 53.5% of patients responded to the drug, with 16.8% experiencing no detectable signs of cancer following treatment and 36.6% seeing a reduction in tumour size. Crucially, these benefits typically lasted for over two years.
Julian Beach, Executive Director of Healthcare Quality and Access at the MHRA, welcomed this significant development. 'This approval offers new hope to adults living with advanced MCC,' he said. 'It's a crucial step forward in providing treatment options for those who need them most.' The MHRA will continue to closely monitor the safety and effectiveness of Retifanlimab as it becomes more widely used across the UK.
The approval, granted to Incyte Biosciences UK Ltd, was given via the International Recognition Procedure (IRP), which recognises assessments from trusted international regulatory partners. Details on the drug, including its Summary of Product Characteristics and Patient Information Leaflets, will be available on the MHRA Products website within seven days.