The purpose of this article is to report the translational process of an implantable microdevice platform with an emphasis on the technical and engineering adaptations for patient use, regulatory advances, and successful integration into clinical workflow. Methods: We developed design adaptations for implantation and retrieval, established ongoing monitoring and testing, and facilitated regulatory advances that enabled the administration and examination of a large set of cancer therapies simultaneously in individual patients. Results: Six applications for oncology studies have successfully proceeded to patient trials, with future applications in progress. Conclusion: First-in-human translation required engineering design changes to enable implantation and retrieval that fit with existing clinical workflows, a regulatory strategy that enabled both delivery and response measurement of up to 20 agents in a single patient, and establishment of novel testing and quality control processes for a drug/device combination product without clear precedents. Significance: This manuscript provides a real-world account and roadmap on how to advance from animal proofof-concept into the clinic, confronting the question of how to use research to benefit patients.

By observing the activity of anti-cancer agents directly in tumors, there is potential to greatly expand our understanding of drug response and develop more personalized cancer treatments. Implantable microdevices (IMD) have been recently developed to deliver microdoses of chemotherapeutic agents locally into confined regions of live tumors; the tissue can be subsequently removed and analyzed to evaluate drug response. This method has the potential to rapidly screen multiple drugs, but requires surgical tissue removal and only evaluates drug response at a single timepoint when the tissue is excised. Here, we describe a “lab-in-a-tumor” implantable microdevice (LIT-IMD) platform to image cell-death drug response within a live tumor, without requiring surgical resection or tissue processing. The LIT-IMD is inserted into a live tumor and delivers multiple drug microdoses into spatially discrete locations. In parallel, it locally delivers microdose levels of a fluorescent cell-death assay, which diffuses into drug-exposed tissues and accumulates at sites of cell death. An integrated miniaturized fluorescence imaging probe images each region to evaluate drug-induced cell death. We demonstrate ability to evaluate multi-drug response over 8 h using murine tumor models and show correlation with gold-standard conventional fluorescence microscopy and histopathology. This is the first demonstration of a fully integrated platform for evaluating multiple chemotherapy responses in situ. This approach could enable a more complete understanding of drug activity in live tumors, and could expand the utility of drug-response measurements to a wide range of settings where surgery is not feasible.

Implantable drug-delivery microdevices are a key diagnostic and therapeutic tool in medicine with increasing applications. Preparation of such combination drug-delivery devices for human studies requires the development of methods to ensure sterility, safety and integrity on both the device and drug side. Despite growing applications for these technologies, there has been a lack of clear methodology regarding sterilization and preparation to meet strict guidelines set forth by the Food and Drug Administration (FDA). Our laboratory developed a set of widely applicable and straightforward procedures to prepare drug-device combination products for clinical use that consistently achieve the high-quality standards provided by the FDA. This includes several newly developed methods for preparation of the implant including endotoxin removal, appropriate sterilization of raw materials, formulation of novel pharmaceutical agents, and loading of agents into drug delivery reservoirs. We also discuss protocols and methods developed with FDA to meet regulatory guidelines to ensure continual sterility and endotoxin testing, as well as longer-term stability testing of drugs and biologic agents. Endotoxin removal and sterilization of raw materials for clinical use. Formulation and device loading of novel pharmaceutical agents. Continued testing of pharmaceutical agents and devices to meet regulatory guidelines.

Advances in the intratumor measurement of drug responses have included a pioneering biomedical microdevice for high throughput drug screening in vivo, which was further advanced by integrating a graded-index lens based two-dimensional fluorescence micro-endoscope to monitor tissue responses in situ across time. While the previous system provided a bulk measurement of both drug delivery and tissue response from a given region of the tumor, it was incapable of visualizing drug distribution and tissue responses in a three-dimensional (3D) way, thus missing the critical relationship between drug concentration and effect. Here we demonstrate a next-generation system that couples multiplexed intratumor drug release with continuous 3D spatial imaging of the tumor microenvironment via the integration of a miniaturized two-photon micro-endoscope. This enables optical sectioning within the live tissue microenvironment to effectively profile the entire tumor region adjacent to the microdevice across time. Using this novel microimaging-microdevice (MI-MD) system, we successfully demonstrated the four-dimensional imaging (3 spatial dimensions plus time) of local drug delivery in tissue phantom and tumors. Future studies include the use of the MI-MD system for monitoring of localized intra-tissue drug release and concurrent measurement of tissue responses in live organisms, with applications to study drug resistance due to nonuniform drug distribution in tumors, or immune cell responses to anti-cancer agents.

Tumor-infiltrating immune cells experience significant metabolic reprogramming in the tumor microenvironment (TME), and they share similar metabolic pathways and nutrient needs with malignant cells. This positions these cell types in direct nutrient competition in the TME. We currently lack a complete understanding of the similarities, differences, and functional consequences of the metabolic pathways utilized by activated immune cells from different lineages versus neoplastic cells. This study applies a novel in situ approach using implantable microdevices to expose the tumor to 27 controlled and localized metabolic perturbations in order to perform a systematic investigation into the metabolic regulation of the cellular fitness and persistence between immune and tumor cells directly within the native TME. Our findings identify the most potent metabolites, notably glutamine and arginine, that induce a favorable metabolic immune response in a mammary carcinoma model, and reveal novel insights on less characterized pathways, such as cysteine and glutathione. We then examine clinical samples from cancer patients to confirm the elevation of these pathways in tumor regions that are enriched in activated T cells. Overall, this work provides the first instance of a highly multiplexed in situ competition assay between malignant and immune cells within tumors using a range of localized microdose metabolic perturbations. The approach and findings may be used to potentiate the effects of T cell stimulating immunotherapies on a tumor-specific or personalized basis through targeted enrichment or depletion of specific metabolites.

Objective: To evaluate the safety and feasibility of implantation and retrieval of a novel implantable microdevice (IMD) in NSCLC patients undergoing operative resection. Background: Adjuvant therapy has limited impact on postsurgical outcomes in NSCLC due to the inability to predict optimal treatment regimens. Methods: An IMD measuring 6.5 mm by 0.7 mm, containing micro-reservoirs allowing for high-throughput localized drug delivery, was developed and loaded with 12 chemotherapeutic agents. Five patients with peripheral lung lesions larger than 1.0 cm were enrolled in this phase 1 clinical study. IMDs were inserted into tumors intraoperatively under direct vision, removed with the resected specimen, and retrieved in pathology. Surrounding tissues were sectioned, stained, and analyzed for tissue drug response to the IMD-delivered microdoses of these agents by a variety of pharmacodynamic markers. Results: A total of 14 IMDs were implanted intraoperatively with 13 (93%) successfully retrieved. After technique refinement, IMDs were reliably inserted and retrieved in open, Video-Assisted Thoracoscopic Surgery, and robotic cases. No severe adverse reactions were observed. The one retained IMD has remained in place without movement or any adverse effects. Analysis of patient blood revealed no detection of chemotherapeutic agents. We observed differential sensitivities of patient tumors to the drugs on the IMD. Conclusions: A multi-drug IMD can be safely inserted and retrieved into lung tumors during a variety of surgical approaches. Future studies will encompass preoperative placement to better examine specific tumor responsiveness to therapeutic agents, allowing clinicians to tailor treatment regimens to the microenvironment of each patient.

One of the major shortcomings of nano carriers-assisted cancer therapeutic strategies continues to be the inadequate tumor penetration and retention of systemically administered nanoformulations and its off-target toxicity. Stromal parameters-related heterogeneity in enhanced permeability and retention effect and physicochemical properties of the nanoformulations immensely contributes to their poor tumor extravasation. Herein, a novel tumor targeting strategy, where an intratumorally implanted micromagnet can significantly enhance accumulation of magneto-plasmonic nanoparticles (NPs) at the micromagnet-implanted tumor in bilateral colorectal tumor models while limiting their off-target accumulation, is demonstrated. To this end, novel multimodal gold/iron oxide NPs comprised of an array of multifunctional moieties with high therapeutic, sensing, and imaging potential are developed. It is also discovered that cancer cell targeted NPs in combination with static magnetic field can selectively induce cancer cell death. A multimodal caspase-3 nanosensor is also developed for real-time visualization of selective induction of apoptosis in cancer cells. In addition, the photothermal killing capability of these NPs in vitro is evaluated, and their potential for enhanced photothermal ablation in tissue samples is demonstrated. Building on current uses of implantable devices for therapeutic purposes, this study envisions the proposed micromagnet-assisted NPs delivery approach may be used to accelerate the clinical translation of various nanoformulations.

A main impediment to effective development of new therapeutics for central nervous system disorders, and for the in vivo testing of biological hypotheses in the brain, is the ability to rapidly measure the effect of novel agents and treatment combinations on the pathophysiology of native brain tissue. We have developed a miniaturized implantable microdevice (IMD) platform, optimized for direct stereotactic insertion into the brain, which enables the simultaneous measurement of multiple drug effects on the native brain tissue in situ. The IMD contains individual reservoirs which release microdoses of single agents or combinations into confined regions of the brain, with subsequent spatial analysis of phenotypic, transcriptomic or metabolomic effects. Using murine models of Alzheimer’s disease (AD), we demonstrate that microdoses of various approved and investigational CNS drugs released from the IMD within a local brain region exhibit in situ phenotypes indicative of therapeutic responses, such as neuroprotection, reduction of hyperphosphorylation, immune cell modulation, and anti-inflammatory effects. We also show that local treatments with drugs affecting metabolism provide evidence for regulation of metabolite profiles and immune cell function in hMAPT AD mice. The platform should prove useful in facilitating the rapid testing of pharmacological or biological treatment hypotheses directly within native brain tissues (of various animal models and in patients) and help to confirm on-target effects, in situ pharmacodynamics and drug-induced microenvironment remodeling, much more efficiently than currently feasible.