A study looking at pembrolizumab for children and teenagers with a solid tumour or lymphoma (KEYNOTE 051)

You may be able to join this study if all of the following apply.

• You have advanced melanoma, or a solid tumour including brain tumours or lymphoma that has continued to grow or has come back despite treatment, or that has spread elsewhere in your body. If you have a cancer other than melanoma, it must produce a protein called PD-L1 (your doctor will test for this)
• Your cancer can be measured using a scan
• If you are between 6 months and 16 years old, you must be up and around even if you are not playing as energetically as normal and spend less time than usual playing (Lansky Play Scale of 70 or more)
• If you are 17 years old, you must be able to care for yourself even if you are not able to carry on with all your normal activities or do active work (Karnofsky score of 70 or more)
• You have satisfactory blood test results
• You are at least 6 months old but haven’t yet reached your 18th birthday. If you have melanoma you must be at least 12 years old but haven't reached your 18th birthday
• You are willing to use reliable contraception during the time of the study and for up to 4 months afterwards if you are sexually active and there is any chance you or your partner could become pregnant

You cannot join this study if any of these apply. You

• Are already taking part in a clinical trial or research study, or have had an experimental treatment in the last 4 weeks
• Have already had an anti PD-L1 or anti PD-L2 drug such as ipilimumab, unless you have had this as a treatment for melanoma
• Are having treatment that affects your immune system, though certain steroid therapy may be allowed (your doctor can advise you about this)
• Have had treatment with an anti cancer  monoclonal antibody in the last 4 weeks
• Have not recovered from any side effects due to having had a monoclonal antibody in the past
• Have had chemotherapy, other cancer drugs or radiotherapy in the last 2 weeks
• Have had a stem cell transplant using donor stem cells in the last 5 years
• Have not recovered from any major surgery
• Have had a live vaccine in the last 30 days
• Have another type of cancer that needs treatment except for successfully treated squamous cell skin cancer or carcinoma in situ of the cervix
• Have cancer that has spread to your brain, including the brain stem or spinal cord and is causing symptoms (you can take part if cancer spread to your brain was treated at least 4 weeks ago and is not causing symptoms)
• Have a problem with your immune system making you more likely to get infections
• Have an autoimmune disease for which you have had treatment that reaches your whole body (systemic treatment) such as drugs that suppress the immune system in the last 2 years (some other types of drugs are allowed and your doctor can advise you about this)
• Have a lung condition called pneumonitis or you have had pneumonitis in the past and needed treatment with steroids
• Have an infection which needs treatment
• Have HIV or active hepatitis B or C
• Have any other medical or mental health problems that the study team think could prevent you taking part
• Are pregnant or breastfeeding