NCT03517449

Who might be able to join this trial:

• You have been diagnosed with endometrial cancer (cancer of the lining of the uterus), confirmed by a tissue sample (biopsy)
• Your cancer has spread, come back, or reached an advanced stage
• Your cancer got worse after receiving at least one chemotherapy treatment containing platinum (you may have had one additional round of platinum-based chemotherapy before or after surgery)
• You are able to provide a tissue sample (either from a previous biopsy or a new one) so researchers can check a specific feature of your tumour called mismatch repair (MMR) status
• Your cancer can be measured on a scan, with at least one visible area of disease confirmed by an independent review team
• You are generally well enough to carry out light activity and care for yourself (confirm with trial site for exact fitness level required), assessed within 7 days of starting treatment
• You are not pregnant or breastfeeding, and you agree to use a highly effective form of contraception during treatment and for at least 120 days after your last dose (or 180 days, depending on which treatment you receive)

Who may not be able to join:

• You have a specific type of uterine cancer called carcinosarcoma, leiomyosarcoma, or endometrial stromal sarcoma
• You have cancer that has spread to the brain and is not stable
• You have had another active cancer (other than endometrial cancer, certain fully treated skin or in-situ cancers) within the past 2 years
• You have a condition affecting how your digestive system absorbs medication, such as certain bowel problems or previous bowel surgery (confirm with trial site)
• You have a pre-existing severe abnormal passage or channel (fistula) between organs, rated Grade 3 or higher (confirm with trial site)
• Scans show that your cancer has grown into or around a major blood vessel
• You have had significant coughing up of blood or tumour bleeding within the 2 weeks before starting the trial
• You have had serious heart problems — such as heart failure, unstable chest pain, a heart attack, a stroke, or a dangerous irregular heartbeat — within the past 12 months
• You currently have an infection that requires treatment with antibiotics or other medicines
• You have not fully recovered from a major operation before starting the trial
• You are HIV positive
• You have active Hepatitis B or Hepatitis C
• You have had lung inflammation (pneumonitis) in the past that needed steroid treatment, or you currently have lung inflammation
• You have a psychiatric illness or substance use problem that would make it difficult to follow the trial requirements
• You have an immune system deficiency, are taking steroid medicines above a certain dose, or are on other medicines that suppress your immune system
• You have an active autoimmune disease (a condition where your immune system attacks your own body) that has needed treatment in the past 2 years — except for psoriasis
• You are pregnant or breastfeeding
• You have received an organ or tissue transplant from another person
• You have received more than one chemotherapy treatment (outside of pre- or post-surgery treatment) for endometrial cancer
• You have received any cancer treatment within the past 28 days, or have not recovered from side effects of previous treatments (with some exceptions such as hair loss)
• You have previously been treated with certain targeted or immunotherapy drugs, including anti-VEGF therapies or immune checkpoint drugs (such as anti-PD-1, anti-PD-L1, or anti-PD-L2 agents)
• You previously received a different type of immune-based therapy and had to stop it due to a serious (Grade 3 or higher) immune-related side effect (confirm with trial site)
• You have had radiotherapy within the past 21 days (radiation to bone for pain relief may be allowed if finished at least 2 weeks before, and you have recovered from any side effects)
• You have received a live vaccine within the past 30 days
• You are known to be intolerant or allergic to any of the medicines used in this trial
• You have previously taken part in a clinical trial studying the combination of pembrolizumab and lenvatinib for endometrial cancer
• You are currently taking part in, or have recently been involved in, another trial of an experimental medicine or device within the past 4 weeks
• Your urine protein levels are