The IMmunotherapy Pleural 5-ALA PDT

Inclusion Criteria:

• ECOG Performance status (PS) 0-1 (WHO)

• Unresectable Malignant Pleural Mesothelioma

• suffering from unresectable MPM (n=20), relapsing after one or 2 lines of treatmentwith platinum-based doublet of chemotherapy (including pemetrexed) [Note: MPMpatients having contra-indications for, or refusing chemotherapy may also berecruited], and candidate for palliative pleural procedure (i.e. thoracoscopy forpleurodesis by talc or by insertion of indwelled pleural catheter, IPC)

• Documented progression after previous 1 or 2 lines of chemotherapy includingPlatinum/Pemetrexed chemotherapy*

• Measurable disease according to modified RECIST 1.1. for MPM

• Malignant pleural lesion assessed to be accessible by local PDT treatment duringthoracoscopy, as validated by expert MTB ("MESOCLIN", Lille, France)

• Histological diagnosis confirmed by national expert pathology panel ("MESOPATH" -Institut Léon Bérard, Lyon, France)

• Weight loss <10%

• available tumor tissue (archival or fresh)

• obtention of an informed written consent before any specific procedure of the study

• Decision to treat the patient within this clinical trial taken during MPM dedicatedmultidisciplinary board (RCP MESOCLIN in France )

• Patient affiliated to and covered by social security for standard care

• Women of child-bearing potential must use a highly effective method of contraceptionfor 28 days prior to the first dose of investigational product, and must agree tocontinue using such precautions for 5 months after the final dose of investigationalproduct

• Women of child-bearing potential must have a negative pregnancy test within 24hbefore administration of investigational product

• First line patients may also be recruited if they declined or if they havecontra-indications for chemotherapy.

Exclusion Criteria:

• lack of informed written consent; or refusal to sign or to participate

• Pregnant, breastfeeding patients, and female patients of childbearing potential whoare unwilling or unable to use a highly effective method of contraception asoutlined in the protocol for the duration of the study and for at least 5 monthsafter the last dose of nivolumab

• Male patients who are unwilling or unable to use contraception methods for theduration of the study and for at least 7 months after the last dose of nivolumab

• a previous treatment by anti-PD-1 or anti-PD-L1 antibodies for their cancer or anyother cancer in the last 5 years

• hypersensitivity to Nivolumab (anti-PD-1 antibodies)

• contra-indications for 5-ALA or PDT

• contra-indications for thoracoscopy (VATS)

• any other comorbidity precluding the feasibility of the therapeutic protocol:uncontrolled cardiac failure, pulmonary hypertension, liver or kidney severedysfunction (creatinin clearance <60 ml/min), uncontrolled infection, or otherdisease according to the investigator

• other cancer treated within 5 years before inclusion except baso-cellular skincarcinoma or cervical / bladder in situ carcinoma

• inability to receive study information and to give informed consent

• patient unable to have a clinical follow-up due to psychological, familial, socialor geographical reasons

• legal incapacity (people in jail), or under supervision (i.e. guardianship orcuratorship)

• treatment with experimental drug within 30 days before the start of the study