Intervention: TALC
Trial phase: Phase 4
SMILES: [H][O-].[H][O-].[Mg+2].[Mg+2].[Mg+2].[O-2].[O-2].[O-2].[O-2].[O-2].[O-2].[O-2].[O-2].[O-2].[O-2].[Si+4].[Si+4].[Si+4].[Si+4]
Sex: All
Age groups: Adult | Older Adult
Healthy volunteers: No
Participants at risk: 2
Group description: This arm consists of eligible participants who are randomized to the Talc arm and would receive Talc therapy instilled into the pleural catheter.

Talc: All patients randomized to the Talc arm will receive Talc therapy through the pleural catheter.
Eligibility criteria:
Inclusion Criteria:

Male or female, at least 18 years of age, inclusive.

Subject has a symptomatic MPE requiring intervention. For an effusion to be defined as malignant, at least one of the following must be true:

There is histocytological confirmation of pleural malignancy
The effusion is an exudate (per Light's criteria) in the context of histocytologically proven malignancy elsewhere, with no other clear cause for fluid identified.
Subject has a history of at least 1 ipsilateral pleural effusion causing dyspnea that responded to thoracentesis where the lung expanded and the dyspnea was improved.
Subject is willing and able to provide written informed consent.
Subject is willing and able to meet all study requirements, including follow-up visits and receiving study-related telephone calls.
Subject has sufficient pleural fluid to allow safe insertion of an IPC.
Subject has negative pregnancy test if appropriate.
Subject or caregiver is able to perform home drainage of the pleural effusion (a caregiver can be a friend, family member, or paid healthcare professional).

Exclusion Criteria:

Subject has significant trapped lung, or a proximal bronchial obstruction which is likely to lead to trapped lung. For a subject to be eligible for this study, two separate study center clinicians must agree that there is no significant trapped lung on the same CXR using visual estimation (reference guide). The CXR used to make this decision must have been performed ≤30 days preceding the consent form being signed, and must have been performed preferably on the same day, but no more than 7 calendar days after tunneled pleural catheter insertion. Significant trapped lung is deemed present if any 1 of the following criteria is met:

A CXR shows hydropneumothorax other than small (< 1 cm between chest wall and pleural line) apical pneumothoraces.
A CXR shows ≥20% of the affected hemithorax to be free of the expected lung parenchymal markings and there is no suggestion of pleural fluid.
A CXR shows ≥20% of the affected hemithorax to be occupied with pleural fluid AFTER a pleural aspiration which resulted in symptoms suggestive of trapped lung (e.g., chest pain or cough).
Subject has a Karnofsky score <50, or a World Health Organization (WHO)/ Eastern Cooperative Oncology Group (ECOG) performance status ≥3. Subjects who have a performance status of 3 may be considered for the study if the removal of their fluid would likely improve their performance score by 1 or more.
Subject is pregnant, planning to become pregnant, or is lactating.
Subject has a history of empyema.
Subject has a history of chylothorax.
Subject has an uncorrected coagulopathy.