Safety of panitumumab-IRDye800CW and cetuximab-IRDye800CW for fluorescence-guided surgical navigation in head and neck cancers

Purpose: To demonstrate the safety and feasibility of leveraging therapeutic antibodies for surgical imaging. Procedures: We conducted two phase I trials for anti-epidermal growth factor receptor antibodies cetuximab-IRDye800CW (n=12) and panitumumab-IRDye800CW (n=15). Adults with biopsy-confirmed head and neck squamous cell carcinoma scheduled for standard-of-care surgery were eligible. For cetuximab-IRDye800CW, cohort 1 was intravenously infused with 2.5 mg/m(2), cohort 2 received 25 mg/m(2), and cohort 3 received 62.5 mg/m(2). For panitumumab-IRDye800CW, cohorts received 0.06 mg/kg, 0.5 mg/kg, and 1 mg/kg, respectively. Electrocardiograms and blood samples were obtained, and patients were followed for 30 days post-study drug infusion. Results: Both fluorescently labeled antibodies had similar pharmacodynamic properties and minimal toxicities. Two infusion reactions occurred with cetuximab and none with panitumumab. There were no grade 2 or higher toxicities attributable to cetuximab-IRDye800CW or panitumumab-IRDye800CW; fifteen grade 1 adverse events occurred with cetuximab-I RDye800CW, and one grade 1 occurred with panitumumab-IRDye800CW. There were no significant differences in QTc prolongation between the two trials (p=0.8). Conclusions: Panitumumab-IRDye800CW and cetuximab-IRDye800CW have toxicity and pharmacodynamic profiles that match the parent compound, suggesting that other therapeutic antibodies may be repurposed as imaging agents with limited preclinical toxicology data

Shell effects on acoustic performance of a drug-delivery system activated by ultrasound.

The composition of microcapsules designed for drug delivery significantly impacts their properties. Ultrasound contrast agents, consisting of stabilized microbubbles (MBs), have emerged as versatile potential drug delivery vehicles to both image and overcome challenges associated with systemic chemotherapy. In our development of polylactic acid MBs decorated with immune-shielding polyethylene glycol chains, we have shown that the balance between acoustic behavior and immune avoidance was scalable and amenable to two distinct PEGylation methods, either incorporation of 5 wt% PEGylated PLA or insertion of 1 wt% PEGylated lipid (LipidPEG) in the polymeric shell. Here we describe the effects of shell compositions on MB functionalization for use in targeted cancer therapy. We chose tumor necrosis factor-related apoptosis inducing ligand (TRAIL) as the targeting ligand, motivated by the ability to both target cells and selectively induce tumor cell death upon binding. Additionally, the MBs were designed to co-encapsulate the chemotherapeutic doxorubicin (Dox) within the shell that works with TRAIL to sensitize resistant cells. We have previously shown that the MBs shatter in response to ultrasound focused at the tumor site, delivering drug-eluting fragments. This study demonstrates the effect of shell characteristics and MB functionalization (TRAIL-ligated and Dox-loaded MBs) on the acoustic response of MBs, and the cumulative effect of shell type. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 3189-3196, 2017

First-in-human intraoperative near-infrared fluorescence imaging of glioblastoma using cetuximab-IRDye800

IntroductionMaximizing extent of surgical resection with the least morbidity remains critical for survival in glioblastoma patients, and we hypothesize that it can be improved by enhancements in intraoperative tumor detection. In a clinical study, we determined if therapeutic antibodies could be repurposed for intraoperative imaging during resection.MethodsFluorescently labeled cetuximab-IRDye800 was systemically administered to three patients 2 days prior to surgery. Near-infrared fluorescence imaging of tumor and histologically negative peri-tumoral tissue was performed intraoperatively and ex vivo. Fluorescence was measured as mean fluorescence intensity (MFI), and tumor-to-background ratios (TBRs) were calculated by comparing MFIs of tumor and histologically uninvolved tissue.ResultsThe mean TBR was significantly higher in tumor tissue of contrast-enhancing (CE) tumors on preoperative imaging (4.0 ± 0.5) compared to non-CE tumors (1.2 ± 0.3; p = 0.02). The TBR was higher at a 100 mg dose than at 50 mg (4.3 vs. 3.6). The smallest detectable tumor volume in a closed-field setting was 70 mg with 50 mg of dye and 10 mg with 100 mg. On sections of paraffin embedded tissues, fluorescence positively correlated with histological evidence of tumor. Sensitivity and specificity of tumor fluorescence for viable tumor detection was calculated and fluorescence was found to be highly sensitive (73.0% for 50 mg dose, 98.2% for 100 mg dose) and specific (66.3% for 50 mg dose, 69.8% for 100 mg dose) for viable tumor tissue in CE tumors while normal peri-tumoral tissue showed minimal fluorescence.ConclusionThis first-in-human study demonstrates the feasibility and safety of antibody based imaging for CE glioblastomas

Detection of visually occult metastatic lymph nodes using molecularly targeted fluorescent imaging during surgical resection of pancreatic cancer

Background: Although most patients with PDAC experience distant failure after resection, a significant portion still present with local recurrence. Intraoperative fluorescent imaging can potentially facilitate the visualization of involved peritumoral LNs and guide the locoregional extent of nodal dissection. Here, the efficacy of targeted intraoperative fluorescent imaging was examined in the detection of metastatic lymph nodes (LNs) during resection of pancreatic ductal adenocarcinoma (PDAC). Methods: A dose-escalation prospective study was performed to assess feasibility of tumor detection within peripancreatic LNs using cetuximab-IRDye800 in PDAC patients. Fluorescent imaging of dissected LNs was analyzed ex vivo macroscopically and microscopically and fluorescence was correlated with histopathology. Results: A total of 144 LNs (72 in the low-dose and 72 in the high-dose cohort) were evaluated. Detection of metastatic LNs by fluorescence was better in the low-dose (50 mg) cohort, where sensitivity and specificity was 100% and 78% macroscopically, and 91% and 66% microscopically. More importantly, this method was able to detect occult foci of tumor (measuring < 5 mm) with a sensitivity of 88% (15/17 LNs). Conclusion: This study provides proof of concept that intraoperative fluorescent imaging with cetuximab-IRDye800 can facilitate the detection of peripancreatic lymph nodes often containing subclinical foci of disease

Intraoperative Pancreatic Cancer Detection using Tumor-Specific Multimodality Molecular Imaging

Background: Operative management of pancreatic ductal adenocarcinoma (PDAC) is complicated by several key decisions during the procedure. Identification of metastatic disease at the outset and, when none is found, complete (R0) resection of primary tumor are key to optimizing clinical outcomes. The use of tumor-targeted molecular imaging, based on photoacoustic and fluorescence optical imaging, can provide crucial information to the surgeon. The first-in-human use of multimodality molecular imaging for intraoperative detection of pancreatic cancer is reported using cetuximab-IRDye800, a near-infrared fluorescent agent that binds to epidermal growth factor receptor. Methods: A dose-escalation study was performed to assess safety and feasibility of targeting and identifying PDAC in a tumor-specific manner using cetuximab-IRDye800 in patients undergoing surgical resection for pancreatic cancer. Patients received a loading dose of 100 mg of unlabeled cetuximab before infusion of cetuximab-IRDye800 (50 mg or 100 mg). Multi-instrument fluorescence imaging was performed throughout the surgery in addition to fluorescence and photoacoustic imaging ex vivo. Results: Seven patients with resectable pancreatic masses suspected to be PDAC were enrolled in this study. Fluorescence imaging successfully identified tumor with a significantly higher mean fluorescence intensity in the tumor (0.09 ± 0.06) versus surrounding normal pancreatic tissue (0.02 ± 0.01), and pancreatitis (0.04 ± 0.01; p < 0.001), with a sensitivity of 96.1% and specificity of 67.0%. The mean photoacoustic signal in the tumor site was 3.7-fold higher than surrounding tissue. Conclusions: The safety and feasibilty of intraoperative, tumor-specific detection of PDAC using cetuximab-IRDye800 with multimodal molecular imaging of the primary tumor and metastases was demonstrated