Silver Nitrate-coated versus Standard Indwelling Pleural Catheter for Malignant Effusions: The SWIFT Randomized Trial.

Rationale: Tunneled, indwelling pleural catheters (IPCs) have been demonstrated to be an effective method of managing malignant pleural effusions. However, they allow pleurodesis and can therefore be removed in only a subset of patients. A novel, silver nitrate-coated IPC was developed with the intention of creating a rapid, effective chemical pleurodesis to allow more frequent and earlier catheter removal. This study represents the pivotal clinical trial evaluating that catheter versus the standard IPC. Objectives: To compare the efficacy of a novel silver nitrate-eluting indwelling pleural catheter (SNCIPC) with that of a standard, uncoated catheter. Methods: The SWIFT [A Pivotal Multi-Center, Randomized, Controlled, Single-Blinded Study Comparing the Silver Nitrate-Coated Indwelling Pleural Catheter (SNCIPC) to the Uncoated PleurX® Pleural Catheter for the Management of Symptomatic, Recurrent, Malignant Pleural Effusions] trial was a multicenter, parallel-group, randomized, controlled, patient-blind trial. Central randomization occurred according to a computer-generated schedule, stratified by site. Recruitment was from 17 secondary or tertiary care hospitals in the United States and 3 in the United Kingdom and included adult patients with malignant pleural effusion needing drainage, without evidence of lung entrapment or significant loculation. The intervention group underwent insertion of an SNCIPC with maximal fluid drainage, followed by a tapering drainage schedule. The control group received a standard, uncoated catheter. Follow-up was conducted until 90 days. The primary outcome measure was pleurodesis efficacy, measured by fluid drainage, at 30 days. Results: A total of 119 patients were randomized. Five withdrew before receiving treatment, leaving 114 (77 SNCIPC, 37 standard IPC) for analysis. The mean age was 66 years (standard deviation, 11). More patients in the SNCIPC group were inpatients (39% vs. 14%; P = 0.009). For the primary outcome, pleurodesis rates were 12 (32%) of 37 in the control group and 17 (22%) of 77 in the SNCIPC group (rate difference, -0.10; 95% confidence interval, -0.30 to 0.09). Median time to pleurodesis was 11 days (interquartile range, 9 to 23) in the control group and 4 days (interquartile range, 2 to 15) in the SNCIPC group. No significant difference in treatment-related adverse event rates was noted between groups. Conclusions: The SNCIPC did not improve pleurodesis efficacy compared with a standard IPC. This study does not support the wider use of the SNCIPC device. Clinical trial registered with www.clinicaltrials.gov (NCT02649894).

Local and systemic effects of a silver nitrate coated indwelling pleural catheter in an animal model of pleurodesis.

Purpose/Aim of the study: This study assessed the safety and potential toxicity of a silver nitrate coated indwelling pleural catheter (SNCIPC) designed to create pleurodesis in a large animal model. MATERIALS AND METHODS: Sixteen animals underwent insertion of either a SNCIPC or an uncoated silicone catheter. Half of the animals were sacrificed at day 7 and the others at day 30. Animal weight and assessment of well-being, pleural fluid and blood collection were performed at regular intervals. Pleurodesis was assessed at necropsy and histopathological examination of organs performed. RESULTS: No mortality or significant clinical findings were observed throughout the experiment. SNCIPC treated animals had increased pleural fluid drainage overall (p < 0.001) and specifically on days 1-4. No differences in hemoglobin, white blood cell count or neutrophil counts were detected between groups. No treatment related histological findings were observed in any of the evaluated tissues outside of the treated area. Serum silver levels in SNCIPC catheter treated animals peaked on Day 4 (0.185 µg/mL, 30 day group) then gradually decreased for the remainder of the study period. The highest tissue silver concentrations were noted in the SNCIPC groups in tissues close to the treatment site in addition to the liver (59.8ug/g +/- 8.6 and 73.3ug/g +/- 25). Pleurodesis scores were significantly higher in SNCIPC treated animals for both the 7 day (median 6.5 vs. 1.0, p = 0.029) and 30 day cohorts (median 7.0 vs. 1.5, p = 0.029). CONCLUSIONS: SNCIPC are well tolerated and not associated with any significant signs of toxicity. Silver levels were elevated in local tissues, serum and liver but without evidence of pathological impact. Effective pleurodesis was present by day 7 and more established by day 30. Clinical studies to investigate the safety and efficacy of this device in patients with malignant pleural effusions appear warranted.