Inclusion Criteria:
* Histologically and/or cytologically confirmed malignant pleural mesothelioma.
* Unresectable disease
* Measurable disease, defined as at least 1 lesion (measurable) that can be accurately assessed at baseline by computed tomography (CT) or magnetic resonance imaging (MRI) and is suitable for repeated assessment (modified RECIST).
* Available unstained archived tumor tissue sample in sufficient quantity to allow for analyses. At least fifteen unstained slides or a tumor block (preferred). NOTE: A fine needle aspiration sample is not sufficient to make the patient eligible for enrollment. Given the complexity of mesothelioma pathological diagnosis , it is expected that they will have a core needle biopsy or surgical tumor biopsy as part of their initial diagnostic work up.
* Age ≥ 18 years.
* Eastern Cooperative Oncology Group (ECOG) performance status of 0 - 1.
* Willing to provide archived tumor tissue and blood samples for research.
* Adequate organ function as defined below
1. Haemoglobin ≥ 9.0 g/dL
2. Absolute neutrophil count (ANC) 1.5 (or 1.0) x (\> 1500 per mm3)
3. Platelet count ≥100 (or 75) x 109/L (\>75,000 per mm3)
4. Serum bilirubin ≤1.5 x institutional upper limit of normal (ULN).
5. AST (SGOT)/ALT (SGPT) ≤2.5 x institutional upper limit of normal unless liver metastases are present, in which case it must be ≤5x ULN
6. Measured creatinine clearance (CL)
1. \>40 mL/min
2. Calculated creatinine CL\>40 mL/min (Cockcroft-Gault formula)
3. 24-hour urinecollection for determination of CL
* Males: Creatinine CL (mL/min) =Weight (kg) x (140 - Age) 72 x serum creatinine (mg/dL)
* Females:Creatinine CL (mL/min)=Weight (kg) x (140 - Age)x0.85 72 x serum creatinine (mg/dL)
* Previously treated with at least one line of platinum -pemetrexed
Exclusion Criteria:
* Disease suitable for curative surgery
* Previous treatment with a PD-1 or PD-L1 inhibitor, including nivolumab or any other agent targeting immune checkpoints.
* Non-pleural mesothelioma e.g. mesothelioma arising in peritoneum, tunica vaginalis or any serosal surface other than the pleura.
* Active second malignancy other than non-melanoma skin cancer or cervical carcinoma in situ.
* Symptomatic or uncontrolled brain metastases requiring concurrent treatment, inclusive of but not limited to surgery, radiation and/or corticosteroids (prednisone \>10 mg or equivalent). Surgery, radiation and/or corticosteroids (any dose \>10 mg prednisone equivalent) must have been completed ≥ 2 weeks prior to registration.
* Uncontrolled seizures.
* Current or prior use of immunosuppressive medication within 28 days before the first dose of nivolumab, with the exceptions of intranasal and inhaled corticosteroids or systemic corticosteroids at physiological doses, which are not to exceed 10 mg/day of prednisone, or an equivalent corticosteroid. Standard steroid premedication given prior to chemotherapy or as prophylaxis for imaging contrast allergy should not be counted for this criterion.
* Active or prior documented autoimmune or inflammatory disorders (including inflammatory bowel disease, diverticulitis with the exception of diverticulosis, celiac disease, irritable bowel disease; Wegner syndrome) within the past 2 years. Subjects with vitiligo, alopecia, Grave's disease, or psoriasis not requiring systemic treatment (within the past 3 years) are not excluded.
* History of primary immunodeficiency.
* History of allogeneic organ transplant.
* Uncontrolled intercurrent illness including, but not limited to, ongoing or active infection, symptomatic congestive heart failure, uncontrolled hypertension, unstable angina pectoris, cardiac arrhythmia, active peptic ulcer disease or gastritis, active bleeding diatheses including any subject known to have psychiatric illness/social situations that would limit compliance with study requirements or compromise the ability of the subject to give written informed consent.
* Active infection including tuberculosis (clinical evaluation including: physical examination findings, radiographic findings, positive PPD test, etc.), hepatitis B (known positive HBV surface antigen \[HBsAg\] result), hepatitis C, or human immunodeficiency virus (positive HIV 1/2 antibodies as defined by a positive ELISA test). Patients with a past or resolved HBV infection (defined as the presence of hepatitis B core antibody \[anti-HBc\] and absence of HBsAg) are eligible. Patients positive for hepatitis C (HCV) antibody are eligible only if polymerase chain reaction is negative for HCV RNA. HIV testing is not required in the absence of clinical suspicion.
* Known history of leptomeningeal carcinomatosis.
* Pregnant or lactating women
* Live attenuated vaccination within 30 days prior to study entry or within 30 days of receiving nivolumab.
* Any condition that, in the opinion of the investigator, would interfere with the evaluation of study treatment or interpretation of patient safety or study results.
* History of allergy or hypersensitivity to any of the active substances or excipients in the study drug.
