New treatment option made available for advanced womb cancers

Dostarlimab (also called Jemperli) has been recommended by the National Institute of Health and Care Excellence (NICE) to treat some types of advanced or recurrent womb cancer. 

The drug, which is given alongside chemotherapy, is recommended in people with mismatch repair deficient cancers and/or high microsatellite instability.  

That means cancers that have mutations that prevent them from repairing mistakes in DNA, and those with several mutations in long, repeated sequences of DNA called microsatellites. 

NICE estimates this decision will affect around 500 people with these types of cancer. 

What is dostarlimab?

Dostarlimab is a type of immunotherapy called a monoclonal antibody, which stimulates the immune system to destroy cancer cells.  

It works by attaching to a protein called PD-1 on the surface of cancer cells. This helps the immune system to recognise and attack the cancer. 

It’s administered intravenously for about 30 minutes at a time. 

The main treatment for womb cancer is surgery. This may be followed by radiotherapy or chemotherapy. Dostarlimab will be offered to people whose cancer is stage 3 or 4 or has returned after initial treatment. 

How effective is it?

The NICE committee based their recommendation on evidence from the RUBY-1 trial, which compared treatment with dostarlimab combined with the chemotherapy drugs carboplatin and paclitaxel with a placebo and the same chemotherapy drugs. 

The results showed that dostarlimab was associated with extended time before people’s cancers got bigger compared to those who were given the placebo, and significantly improved overall survival. 

However, the trial only investigated 88 people over a short period of time, leaving the long-term benefits unclear. As such, the long-term cost effectiveness, which NICE uses to determine whether a drug is a suitable use of NHS resources, of dostarlimab is uncertain. 

Therefore, dostarlimab will be made available through the Cancer Drugs Fund while more evidence is collected on its long-term efficacy. 

NICE decisions apply to England and are usually adopted in Wales and Northern Ireland. Scotland has a different process for deciding which drugs can be used on the NHS.