NCT02766582

Who might be able to join this trial:

• You have been diagnosed with advanced stage III or IV ovarian, fallopian tube, or primary peritoneal cancer (a specific type called "epithelial").
• You are 18 years of age or older.
• You are willing and able to sign a consent form agreeing to take part in the trial.
• After surgery, there was some cancer remaining, or you have measurable amounts of cancer that can be detected on scans.
• You are willing to have a fresh tissue sample (biopsy) taken from a tumor, taken within 6 weeks before starting treatment (in some cases, an older stored sample may be accepted — confirm with trial site).
• You are well enough to carry out daily activities, as measured by a standard health scale called the ECOG scale, at level 0, 1, or 2 (meaning you are fully active to capable of limited self-care — confirm with trial site).
• Your kidneys, liver, and other organs are working well enough, based on blood tests done within 28 days before starting treatment.
• If you could become pregnant, you have a negative pregnancy test within 72 hours before your first dose of the study medicine.
• If you could become pregnant, you agree to use 2 forms of birth control, or are surgically sterile, or completely abstain from heterosexual activity during the study and for 120 days after your last dose.

Who may not be able to join:

• You are currently taking part in another clinical trial or have received an experimental treatment within the past 4 weeks.
• You have been diagnosed with a condition that weakens your immune system, or you have been taking steroid or immune-suppressing medicines within the past 7 days.
• You have a known history of active tuberculosis (TB).
• You have had an allergic reaction to pembrolizumab (the study drug) or any of its ingredients.
• You have received a type of cancer treatment called a monoclonal antibody within the past 4 weeks, or you are still experiencing side effects from one.
• You have received chemotherapy, targeted therapy, or radiation therapy within the past 2 weeks, or you are still experiencing side effects from these treatments.
• You have not fully recovered from a major surgery before starting the trial.
• You have a history of lung inflammation (not caused by infection) that needed steroid treatment, or you currently have lung inflammation.
• You have had another cancer in the last 3 years that is still active or being treated (with some exceptions for certain minor skin cancers or early-stage cervical changes — confirm with trial site).
• You have cancer that has spread to your brain or the lining around it.
• You have an autoimmune disease (where your immune system attacks your own body) that has needed medical treatment in the past 2 years (simple hormone replacement therapy is generally not counted as this type of treatment — confirm with trial site).
• You have an active infection that requires treatment with medicines.
• You have a medical or mental health condition, or substance use disorder, that would make it difficult to follow the trial requirements, in the opinion of the doctor running the trial.
• You are pregnant, breastfeeding, or planning to become pregnant during the trial or within 120 days after your last dose.
• You have previously been treated with certain types of immune checkpoint therapy (anti-PD-1, anti-PD-L1, or anti-PD-L2 drugs — confirm with trial site).
• You have a known diagnosis of HIV.
• You have known active Hepatitis B or Hepatitis C infection.
• Your ovarian cancer is the borderline type, has come back after previous treatment, or is a non-epithelial type.
• You have received a live vaccine (such as certain flu or travel vaccines) within 30 days before starting the trial.

Important: Always verify eligibility with the trial site directly before applying.