Locoregional Delivery Research Articles

CTIM-02. PIONEERING QUAD-TARGETING CAR T CELL THERAPY IN PEDIATRIC CNS TUMORS – ANALYSIS FROM THE INITIAL PATIENTS TREATED ON THE FIRST-IN-HUMAN PHASE 1 TRIAL BRAINCHILD-04

Abstract BACKGROUND BrainChild-04 is a first-in-human clinical trial of quad-chimeric antigen receptor (CAR) T cell therapy for children and young adults with central nervous system (CNS) tumors. This trial administers repeated locoregional CAR T cells targeting B7-H3, EGFR, HER2, and IL-13Ralpha2 (“quad-CAR T cells”), leveraging multi-antigen targeting to address the tumor heterogeneity of high-grade CNS tumors. METHODS The primary endpoints are feasibility and safety, and secondary endpoints are disease response and correlative studies of CAR T cell activity. The trial utilized a Bayesian Optimal Interval (BOIN) statistical design with three planned dose regimens(DR). There are 2 arms with weekly delivery for 3 weeks of a 4-week cycle:(A) –diffuse intrinsic pontine glioma (DIPG), (B) –non-pontine diffuse midline glioma (DMG) or other relapsed CNS tumors. RESULTS Enrolled patients include DMG N=6, DIPG N=5, other CNS tumors N=4. Of the 15 enrolled patients, 7 have been infused with 8 awaiting infusions. A total of 33 intracranial CAR T doses have been delivered, including Arm A DR 1 (N=1), Arm B DR 1 (N=3), DR2 (N=3). The most common adverse events have been grade 1-2 fever (7/7 patients), grade 1-3 headache (6/7), and grade 1-2 nausea/vomiting (6/7). There have been no DLTs and no cytokine release syndrome (CRS) or immune effector cell-associated neurotoxicity (ICANS). CTCAE and tumor inflammation-associated neurotoxicity are both being captured. All treated patients are alive with median follow up time post-initial infusion of 93(14-198) days. CAR T cells were detected by flow cytometric analysis of CSF post-infusion in 14/24 CSF samples. Radiographic response, CSF circulating tumor DNA, targeted mass spectrometry, and cytokine analysis will be presented. CONCLUSIONS Our preliminary experience suggests tolerability of locoregional delivery of quad-CAR T cells at doses currently evaluated. The trial remains ongoing and these data support continued evaluation of this product to better assess anti-tumor activity in patients with CNS tumors, including DIPG/DMG.

Engineered oncolytic virus expressing B7H3-targeting BiTE enhances antitumor T-cell immune response

BackgroundBispecific T-cell engagers (BiTEs) are recombinant bispecific proteins designed to stimulate polyclonal T-cell immunity. In recent years, B7H3, a pan-cancer antigen, has been considered a promising target for future immunotherapy....

Thermosensitive multivesicular liposomal hydrogel: a potential platform for loco-regional drug delivery in the treatment of osteomyelitis caused by antibiotic-resistant biofilm-forming bacteria.

Biofilm-mediated osteomyelitis presents significant therapeutic challenges. Given the limitations of existing osteomyelitis treatment approaches, there is a distinct need to develop a localized drug delivery system that is biocompatible, biodegradable, and capable of controlled antibiotic release. Multivesicular liposomes (MVLs), characterized by their non-concentric vesicular structure, distinct composition, and enhanced stability, serve as the system for a robust sustained-release drug delivery platform. In this study, various hydrogel formulations composed of poloxamer 407 and other hydrogels, incorporating vancomycin hydrochloride (VAN HL)-loaded MVLs (VAN HL-MVLs), were prepared and evaluated. The optimized VAN HL-MVL sol-gel system, consisting of poloxamer 407 and hyaluronic acid, successfully maintained drug release for up to 3 weeks and exhibited shear-thinning behavior at 37°C. While complete drug release from MVLs alone took place in 312 h, the hydrogel formulation extended this release to 504 h. The released drug effectively inhibited the Staphylococcus aureus biofilms growth within 24 h and methicillin-resistant S. aureus biofilms within 72 h. It also eradicated preformed biofilms of S. aureus and methicillin-resistant S. aureus in 96 and 120 h, respectively. This injectable in situ gel system incorporating VAN HL-MVLs holds potential as an alternative to undergoing multiple surgeries for osteomyelitis treatment and warrants further studies.

Ultrasound and x-ray imageable poloxamer-based hydrogel for loco-regional therapy delivery in the liver

Intratumoral injections have the potential for enhanced cancer treatment efficacy while reducing costs and systemic exposure. However, intratumoral drug injections can result in substantial off-target leakage and are invisible under standard imaging modalities like ultrasound (US) and x-ray. A thermosensitive poloxamer-based gel for drug delivery was developed that is visible using x-ray imaging (computed tomography (CT), cone beam CT, fluoroscopy), as well as using US by means of integrating perfluorobutane-filled microbubbles (MBs). MBs content was optimized using tissue mimicking phantoms and ex vivo bovine livers. Gel formulations less than 1% MBs provided gel depositions that were clearly identifiable on US and distinguishable from tissue background and with minimal acoustic artifacts. The cross-sectional areas of gel depositions obtained with US and CT imaging were similar in studies using ex vivo bovine liver and postmortem in situ swine liver. The gel formulation enhanced multimodal image-guided navigation, enabling fusion of ultrasound and x-ray/CT imaging, which may enhance targeting, definition of spatial delivery, and overlap of tumor and gel. Although speculative, such a paradigm for intratumoral drug delivery might streamline clinical workflows, reduce radiation exposure by reliance on US, and boost the precision and accuracy of drug delivery targeting during procedures. Imageable gels may also provide enhanced temporal and spatial control of intratumoral conformal drug delivery.

Prospects of Synergy: Local Interventions and CAR TCell Therapy in Solid Tumors.

Chimeric antigen receptor Tcell therapy has been established in the treatment of various Bcell malignancies. However, translating this therapeutic effect to treat solid tumors has been challenging because of their inter-tumoral as well as intratumoral heterogeneity and immunosuppressive microenvironment. Local interventions, such as surgery, radiotherapy, local ablation, and locoregional drug delivery, can enhance chimeric antigen receptor Tcell therapy in solid tumors by improving tumor infiltration and reducing systemic toxicities. Additionally, ablation and radiotherapy have proven to (re-)activate systemic immune responses via abscopal effects and reprogram the tumor microenvironment on a physical, cellular, and chemical level. This review highlights the potential synergy of the combined approaches to overcome barriers of chimeric antigen receptor Tcell therapy and summarizes recent studies that may pave the way for new treatment regimens.

Ultrasound and x-ray imageable poloxamer-based hydrogel for loco-regional therapy delivery in the liver.

Intratumoral injections have the potential for enhanced cancer treatment efficacy while reducing costs and systemic exposure. However, intratumoral drug injections can result in substantial off-target leakage and are invisible under standard imaging modalities like ultrasound (US) and x-ray. A thermosensitive poloxamer-based gel for drug delivery was developed that is visible using x-ray imaging (computed tomography (CT), cone beam CT, fluoroscopy), as well as using US by means of integrating perfluorobutane-filled microbubbles (MBs). MBs content was optimized using tissue mimicking phantoms and ex vivo bovine livers. Gel formulations less than 1% MBs provided gel depositions that were clearly identifiable on US and distinguishable from tissue background and with minimal acoustic artifacts. The cross-sectional areas of gel depositions obtained with US and CT imaging were similar in studies using ex vivo bovine liver and postmortem in situ swine liver. The gel formulation enhanced multimodal image-guided navigation, enabling fusion of ultrasound and x-ray/CT imaging, which may enhance targeting, definition of spatial delivery, and overlap of tumor and gel. Although speculative, such a paradigm for intratumoral drug delivery might streamline clinical workflows, reduce radiation exposure by reliance on US, and boost the precision and accuracy of drug delivery targeting during procedures. Imageable gels may also provide enhanced temporal and spatial control of intratumoral conformal drug delivery.

Attenuation of osteoarthritis progression via locoregional delivery of Klotho-expressing plasmid DNA and Tanshinon IIA through a stem cell-homing hydrogel

BackgroundOsteoarthritis (OA) is an aging-related degenerative joint disorder marked by joint discomfort and rigidity. Senescent chondrocytes release pro-inflammatory cytokines and extracellular matrix-degrading proteins, creating an inflammatory microenvironment that hinders chondrogenesis and accelerates matrix degradation. Targeting of senescent chondrocytes may be a promising approach for the treatment of OA. Herein, we describe the engineering of an injectable peptide-hydrogel conjugating a stem cell–homing peptide PFSSTKT for carrying plasmid DNA-laden nanoparticles and Tanshinon IIA (pPNP + TIIA@PFS) that was designed to attenuate OA progression by improving the senescent microenvironment and fostering cartilage regeneration.ResultsSpecifically, pPNP + TIIA@PFS elevates the concentration of the anti-aging protein Klotho and blocks the transmission of senescence signals to adjacent healthy chondrocytes, significantly mitigating chondrocyte senescence and enhancing cartilage integrity. Additionally, pPNP + TIIA@PFS recruit bone mesenchymal stem cells and directs their subsequent differentiation into chondrocytes, achieving satisfactory chondrogenesis. In surgically induced OA model rats, the application of pPNP + TIIA@PFS results in reduced osteophyte formation and attenuation of articular cartilage degeneration.ConclusionsOverall, this study introduces a novel approach for the alleviation of OA progression, offering a foundation for potential clinical translation in OA therapy.

Abstract B017: Novel mesothelin-based CAR T cells targeting MUC16 as an intravesical bladder cancer therapy

Abstract Intravesical therapies have been the mainstay of non-muscle invasive bladder cancer (BC) management; however, their efficacy is limited by toxicities, recurrences, and supply shortages. Consequently, many patients are recommended cystectomy, which is fraught with high complication rates. Thus, bladder-sparing treatments present a major, unmet clinical need. Chimeric antigen receptor (CAR) T cell therapy, wherein T cells are engineered to express an artificial receptor to a target, is an immunotherapeutic approach with efficacy in hematologic malignancies. Similar success in solid tumors has been hindered by a lack of suitable targets, reduced T cell infiltration/activity, and major toxicities, including on-target off-tumor effects and cytokine release syndromes. To overcome these limitations, locoregional delivery of CAR T cells is being investigated. Yet, to date, no studies have examined their potential as intravesical therapies. In this study, we used a computational pipeline using large-scale BC transcriptomics data to discover potential CAR targets which met strict criteria of high cell-surface expression on BC and minimal expression on normal tissue. We identified MUC16, a surface-bound mucinous glycoprotein, as a top candidate from this pipeline, which has more reduced pan-tissue expression than targets of precision-guided therapies in BC. Consistent with prior reports, MUC16 transcript and protein levels increase with grade and T stage and correlates with chemotherapeutic resistance. We also find MUC16 expression persists in recurrent tumors after BCG-therapy. To target MUC16, we designed second-generation CARs based on scFv derived from the antibody 3a5 (3a5-28z) and natural-ligands based on the high-affinity MUC16-mesothelin interaction (MSLN-28z) or its truncated binding domain (truncMSLN-28z) which were fused to CD28 co-stimulatory domains and CD3z chains of the T cell receptor. Using human BC lines with a broad range of MUC16 levels, we show MSLN-28z more effectively lyses MUC16+, but not MUC16−, cells than compared to 3a5-28z or truncMSLN-28z CAR T cells. Ablation of MUC16 by CRISPR/Cas9 or modification of MSLN-based CAR to lack signaling domains abolishes the cytotoxicity of MSLN-28z CAR T cells, demonstrating dependency on MUC16 engagement. Using multiplex assays and intracellular cytokine staining, we further demonstrate MSLN-28z CAR T cells have potent polyfunctionality through secretion of cytokines IL-2, IFN-g, and TNF-a by both CD4+ and CD8+ subsets. Last, in immunodeficient mice orthotopically xenografted with HT1376 cells, intravesical delivery of MSLN-28z CAR T cells enhances survival compared to CAR T cells delivered intravenously. This enhanced anti-tumor response correlates with reduced tumor weights and increased T cell infiltration. Notably, intravesically delivered CAR T cells are not detectable in peripheral circulation of tumor-bearing mice. Together, our findings substantiate MUC16 as a targetable antigen in BC and validate MSLN-based CAR T cells as a potential intravesical therapy. Citation Format: Parwiz Abrahimi, Jonathan Khan, Renier Brentjens, Taha Merghoub, Jedd Wolchok. Novel mesothelin-based CAR T cells targeting MUC16 as an intravesical bladder cancer therapy [abstract]. In: Proceedings of the AACR Special Conference on Bladder Cancer: Transforming the Field; 2024 May 17-20; Charlotte, NC. Philadelphia (PA): AACR; Clin Cancer Res 2024;30(10_Suppl):Abstract nr B017.

Abstract 1419: Locoregional delivery with engineered stem cells modulates immunosuppressive tumor microenvironment in brain leptomeningeal metastasis

Abstract Leptomeningeal metastasis (LM) is one of the severe disease conditions in brain metastasis (BM) and results in poor prognosis and reduction of quality of life. Immunotherapies such as anti-Programmed cell Death (PD)-1 antibodies have shown improved overall survival against non-small cell lung cancer (NSCLC).. However, the clinical benefit of patients with NSCLC derived LM is still limited due to poor penetration of therapeutic agents into the brain and cerebrospinal fluid (CSF) and lack of understanding of the tumor microenvironment in LM. In this study, we first developed immune-competent mouse models of LM which show significantly decreased immune cells and increased PD-1+ T cells in the tumor microenvironment as compared to primary NSCLC tumors, thus mimicking primary and LM NSCL in patients. Next, we explored the use of oncolytic herpes simplex virus (oHSV) that selectively replicate in tumor cells and illicit an antitumor effect via oncolysis and production of neoantigens for targeting LM NSCLC. Given that virus neutralization, and inefficient extravasation are the major barriers to the effective systemic delivery of oHSV to target metastatic tumor lesions in the brain, we utilized mesenchymal stem cells (SC) and created two population of mesenchymal SC types: one for loading oncolytic herpes simplex virus (oHSV) and another one, engineered with knockout of Nectin-1 receptor by CRISPR/Cas9 technique to be resistant to oHSV, for secreting single-chain variable fragment (scFv) anti-PD-1. We show that locoregional treatment improved therapeutic outcomes by inducing oHSV-mediated immunogenic cell death, and activation of anti-tumor T cell signaling in mouse NSCLC LM tumors. Our novel SCs based immunotherapeutic strategy provides a roadmap towards treatment of lung to brain leptomeningeal metastatic patients. Citation Format: Nobuhiko Kanaya, Waleed Seddiq, Kok-Siong Chen, Yoshinori Kajiwara, Lucia Moreno Lama, Shinji Kuroda, Toshiyoshi Fujiwara, Hiroaki Wakimoto, Khalid Shah. Locoregional delivery with engineered stem cells modulates immunosuppressive tumor microenvironment in brain leptomeningeal metastasis [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 1419.

Abstract 4011: Locoregional GPC3 chimeric antigen receptor (CAR)-T cell therapy is associated with improved tumor control in hepatocellular carcinoma by enhancing CAR-T cell trafficking and functionality

Abstract Despite the rapid development of anti-cancer immunotherapy, the prognosis of hepatocellular carcinoma (HCC) patients is far from satisfactory. Glypican-3 (GPC3) CAR-T cell therapy has shown varied patient response. One of the potential reasons of low response rates may be due to the limited CAR-T cell infiltration. Therefore, locoregional GPC3 CAR-T therapy has been a promising option, with a hope of enhancing CAR-T cell tumor penetration. In this study, the therapeutic efficacy and underlying mechanisms of locoregional GPC3 CAR-T cell delivery were explored using HCC mouse xenografts. Orthotopic NOD-scid IL2Rgnull (NSG) HCC models were established by tumor fragment implantation into the liver. CAR-T cell injections were performed via the tail vein and portal vein to simulate systemic and locoregional administrations, respectively. Compared to the systemic treatment, locoregional therapy could better control the tumor growth, and was associated with improved liver function. In addition, the locoregional therapy group demonstrated a higher percentage of tumor-infiltrating CAR-T cells which showed an increased expression level of the cytotoxicity marker GZMB and a reduced level of the exhaustion marker LAG3. Moreover, significantly higher IFN-gamma level was found in the blood of the locoregional therapy group, indicating a better CAR-T cell functionality. In conclusion, we have demonstrated that locoregional administration of CAR-T cells is associated with increased CAR-T cell infiltration and better therapeutic efficacy. Additionally, CAR-T cells being injected locoregionally are correlated with enhanced functionality and reduced exhaustion phenotype. These findings highlight the potential of locoregional GPC3 CAR-T therapy as a promising treatment strategy for HCC patients. Citation Format: Jue Wang, Kinching Tsang, Jiale Qiu, Bo Feng. Locoregional GPC3 chimeric antigen receptor (CAR)-T cell therapy is associated with improved tumor control in hepatocellular carcinoma by enhancing CAR-T cell trafficking and functionality [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 4011.

Locoregional delivery of IL-13Rα2-targeting CAR-T cells in recurrent high-grade glioma: a phase 1 trial

Chimeric antigen receptor T cell (CAR-T) therapy is an emerging strategy to improve treatment outcomes for recurrent high-grade glioma, a cancer that responds poorly to current therapies. Here we report a completed phase I trial evaluating IL-13Rα2-targeted CAR-T cells in 65 patients with recurrent high-grade glioma, the majority being recurrent glioblastoma (rGBM). Primary objectives were safety and feasibility, maximum tolerated dose/maximum feasible dose and a recommended phase 2 dose plan. Secondary objectives included overall survival, disease response, cytokine dynamics and tumor immune contexture biomarkers. This trial evolved to evaluate three routes of locoregional T cell administration (intratumoral (ICT), intraventricular (ICV) and dual ICT/ICV) and two manufacturing platforms, culminating in arm 5, which utilized dual ICT/ICV delivery and an optimized manufacturing process. Locoregional CAR-T cell administration was feasible and well tolerated, and as there were no dose-limiting toxicities across all arms, a maximum tolerated dose was not determined. Probable treatment-related grade 3+ toxicities were one grade 3 encephalopathy and one grade 3 ataxia. A clinical maximum feasible dose of 200 × 106 CAR-T cells per infusion cycle was achieved for arm 5; however, other arms either did not test or achieve this dose due to manufacturing feasibility. A recommended phase 2 dose will be refined in future studies based on data from this trial. Stable disease or better was achieved in 50% (29/58) of patients, with two partial responses, one complete response and a second complete response after additional CAR-T cycles off protocol. For rGBM, median overall survival for all patients was 7.7 months and for arm 5 was 10.2 months. Central nervous system increases in inflammatory cytokines, including IFNγ, CXCL9 and CXCL10, were associated with CAR-T cell administration and bioactivity. Pretreatment intratumoral CD3 T cell levels were positively associated with survival. These findings demonstrate that locoregional IL-13Rα2-targeted CAR-T therapy is safe with promising clinical activity in a subset of patients. ClinicalTrials.gov Identifier: NCT02208362.

Different leukocyte subsets are targeted by systemic and locoregional administration despite conserved nanomaterial characteristics optimal for lymph node delivery.

Lymph nodes (LNs) house a large proportion of the body's leukocytes. Accordingly, engineered nanomaterials are increasingly developed to direct therapeutics to LNs to enhance their efficacy. Yet while lymphatic delivery of nanomaterials to LNs upon locoregional injection has been extensively evaluated, nanomaterial delivery to LN-localized leukocytes after intravenous administration has not been systematically explored nor benchmarked. In this work, a panel of inert, fluorescent nanoscale tracers and drug delivery vehicles were utilized to interrogate intravenous versus locoregionally administered nanomaterial access to LNs and leukocyte subsets therein. Hydrodynamic size and material effects on LN accumulation extents were similar between intravenous versus intradermal injection routes. Nanomaterial distribution to various LN leukocyte subsets differed substantially with injection route, however, in a manner not proportional to total LN accumulation. While intravenously administered nanomaterials accumulated in LNs lowly compared to systemic tissues, in sharp contrast to locoregional delivery, they exhibited size-dependent but material-independent access to immune cells within the LN parenchyma, which are not easily accessed with locoregional delivery.

Penetration enhancers strengthen tough hydrogel bioadhesion and modulate locoregional drug delivery.

The human body possesses natural barriers, such as skin and mucosa, which limit the effective delivery of therapeutics and integration of medical devices to target tissues. Various strategies have been deployed to breach these barriers mechanically, chemically, or electronically. The development of various penetration enhancers (PEs) offers a promising solution due to their ability to increase tissue permeability using readily available reagents. However, existing PE-mediated delivery methods often rely on weak gel or liquid drug formulations, which are not ideal for sustained local delivery. Hydrogel adhesives that can seamlessly interface biological tissues with controlled drug delivery could potentially resolve these issues. Here, we demonstrate that tough adhesion between drug-laden hydrogels and biological tissue (e.g. skin and tumours) can lead to effective local delivery of drugs deep into targeted tissues by leveraging the enhanced tissue penetration mediated by PEs. The drug release profile of the hydrogel adhesives can be fine-tuned by further engineering the nanocomposite hydrogel matrix to elute chemotherapeutics from 2 weeks to 2 months. Using a 3D tumour spheroid model, we demonstrated that PEs increased the cancer-killing effectiveness of doxorubicin by facilitating its delivery into tumour microtissues. Therefore, the proposed tough bioadhesion and drug delivery strategy modulated by PEs holds promise as a platform technique to develop next-generation wearable and implantable devices for cancer management and regenerative medicine.

A porcine model of thoracic aortic aneurysms created with a retrievable drug infusion stent graft mirrors human aneurysm pathophysiology

ObjectiveAneurysm pathophysiology remains poorly understood, in part from the disparity of murine models with human physiology and the requirement for invasive aortic exposure to apply agents used to create aneurysm models. A retrievable drug infusion stent graft (RDIS) was developed to isolate the aortic wall intraluminally for drug exposure. We hypothesized that an RDIS could deliver aneurysm-promoting enzymes to create a porcine model of thoracic aneurysms without major surgical exposure. MethodsRetrievable nitinol stent graft frames were designed with an isolated drug delivery chamber, covered with polytetrafluoroethylene, and connected to a delivery wire with a drug infusion catheter installed to the outer chamber. Institutional Animal Care and Use Committee-approved Yorkshire pigs (n = 5) underwent percutaneous access of the femoral artery, baseline aortogram and stent placement in the thoracic aorta followed by 30-minute exposure to a cocktail of elastase, collagenase, and trypsin. After aspiration of excess drug, stent retrieval, and femoral artery repair, animals were recovered, with angiograms at 1 and 4 weeks followed by explant. Histological analysis, in situ zymography, and multiplex cytokine assays were performed. ResultsThe RDIS isolated a segment of anterior aorta angiographically, while the center lumen preserved distal perfusion during drug treatment (baseline femoral mean arterial pressure, 70 ± 14 mm Hg; after RDIS, 75 ± 12; P = .55). Endovascular induction of thoracic aneurysms did not require prior mechanical injury and animals revealed no evidence of toxicity. Within 1 week, significant aneurysmal growth was observed in all five animals (1.4 ± 0.1 cm baseline to 2.9 ± 0.7 cm; P = .002) and only within the treated region of the aorta. Aneurysms persisted out to 4 weeks. Aneurysm histology demonstrated loss of elastin and collagen that was otherwise preserved in untreated aorta. Proinflammatory cytokines and increased matrix metalloproteinase activity were increased significantly within the aneurysm. ConclusionsAn RDIS achieves isolated drug delivery while preserving distal perfusion to achieve an endovascular porcine model of thoracic aneurysms without major surgery. This model may have value for surgical training, device testing, and to better understand aneurysm pathogenesis. Most important, although the RDIS was used to simulate aortic pathology, this tool offers intriguing horizons for focused therapeutic drug delivery directly to aneurysms and, more broadly, focused locoregional drug delivery to vessels and vascular beds.

Locoregional Delivery of IL-13Rα2–CAR-T cells Is Safe in High-Grade Glioma

Locoregional Delivery of IL-13Rα2–CAR-T cells Is Safe in High-Grade Glioma

Programmable DNA Hydrogel Assisting Microcrystal Formulations for Sustained Locoregional Drug Delivery in Surgical Residual Tumor Lesions and Lymph Node Metastasis.

Surgical residual tumor lesions (R1 resection of surgical procedures (e.g., liver cancer infiltrating the diaphragm, surgical residual breast cancer, postoperative residual ovarian cancer) or boundary residual after ablation) and lymph node metastasis that cannot be surgically resected (retroperitoneal lymph nodes) significantly affect postoperative survival of tumor patients. This clinical conundrum poses three challenges for local drug delivery systems: stable and continuous delivery, good biocompatibility, and the ability to package new targeted drugs that can synergize with other treatments. Here, a drug-laden hydrogel generated from pure DNA strands and highly programmable in adjusting its mesh size is reported. Meanwhile, the DNA hydrogel can assist the microcrystallization of novel radiosensitizing drugs, ataxia telangiectasia and rad3-related protein (ATR) inhibitor (Elimusertib), further facilitating its long-term release. When applied to the tumor site, the hydrogel system demonstrates significant antitumor activity, minimized systemic toxicity, and has a modulatory effect on the tumor-immune cell interface. This drug-loaded DNA-hydrogel platform represents a novel modality for adjuvant therapy in patients with surgical residual tumor lesions and lymph node metastasis.

A landscape of recent advances in lipid nanoparticles and their translational potential for the treatment of solid tumors.

Lipid nanoparticles (LNPs) are biocompatible drug delivery systems that have found numerous applications in medicine. Their versatile nature enables the encapsulation and targeting of various types of medically relevant molecular cargo, including oligonucleotides, proteins, and small molecules for the treatment of diseases, such as cancer. Cancers that form solid tumors are particularly relevant for LNP-based therapeutics due to the enhanced permeation and retention effect that allows nanoparticles to accumulate within the tumor tissue. Additionally, LNPs can be formulated for both locoregional and systemic delivery depending on the tumor type and stage. To date, LNPs have been used extensively in the clinic to reduce systemic toxicity and improve outcomes in cancer patients by encapsulating chemotherapeutic drugs. Next-generation lipid nanoparticles are currently being developed to expand their use in gene therapy and immunotherapy, as well as to enable the co-encapsulation of multiple drugs in a single system. Other developments include the design of targeted LNPs to specific cells and tissues, and triggerable release systems to control cargo delivery at the tumor site. This review paper highlights recent developments in LNP drug delivery formulations and focuses on the treatment of solid tumors, while also discussing some of their current translational limitations and potential opportunities in the field.

In Vitro Assessment of Cisplatin/Hyaluronan Complex for Loco-Regional Chemotherapy

Loco-regional chemotherapy is a strategy used to achieve more precise anticancer drug effect directly on tumor mass, while decreasing whole body exposure, which can lead to undesirable side effects. Thus, the loco-regional chemotherapy is conceptually similar to the targeted drug delivery systems for delivering chemotherapeutics to cancer cells in a certain location of the body. Recently, it has been demonstrated that a novel polymeric film containing the complex between cisplatin (cisPt) and hyaluronan (sodium salt of hyaluronic acid; NaHA) enhanced in vivo efficacy and safety of cisplatin (cisPt) by loco-regional delivery in pleural mesothelioma. Biologically, hyaluronic acid (HA) binds with the CD44 receptor, which is a transmembrane glycoprotein overexpressed by other cancer cells. Thus, administering both cisPt and hyaluronan together as a complex loco-regionally to the tumor site could target cancer cells locally and enhance treatment safety. A slight excess of hyaluronan was required to have more than 85% cisPt complexation. In cell monolayers (2D model) the cisPt/NaHA complex in solution demonstrated dose- and time-dependent cytotoxic effect by decreasing the viability of pancreatic, melanoma, and lung cell lines (they all express CD44). At the same concentration in solution, the complex was as effective as cisPt alone. However, when applied as film to melanoma spheroids (3D model), the complex was superior because it prevented the tumor spheroid growth and, more importantly, the formation of new cell colonies. Hence, cisPt/NaHA complex could work in preventing metastases loco-regionally and potentially avoiding systemic relapses.

Influence of focused ultrasound on locoregional drug delivery to the brain: Potential implications for brain tumor therapy

IntroductionEfficient delivery of therapeutics across the blood-brain barrier (BBB) for the treatment of central nervous system (CNS) tumors is a major challenge to the development of safe and efficacious therapies. Locoregional drug delivery platforms offer an improved therapeutic index by achieving high drug concentrations in the target tissue with negligible systemic exposure. Intrathecal (intraventricular) [IT] and convection-enhanced delivery [CED] are two clinically relevant methods being employed for various CNS malignancies. Both of these standalone platforms suffer from passive post-administration distribution forces, sometimes limiting the desired distribution for tumor therapy. Focused ultrasound and microbubble-mediated blood-brain barrier opening (FUS-BBBO) is a recent modality used for enhanced drug delivery. It is postulated that coupling of FUS with these alternative delivery routes may provide benefits. Multimodality FUS may provide the desired ability to increase the depth of parenchymal delivery following IT administration and provide a means for contour directionality with CED. Further, the transient enhanced permeability achieved with FUS-BBBO is well established, but drug residence and transit times, important to clinical dose scheduling, have not yet been defined. The present investigation comprises two discrete studies: 1. Conduct a comprehensive quantitative evaluation to elucidate the effect of FUS-BBBO as it relates to varying routes of administration (IT and IV) in its capacity to facilitate drug penetration within the striatal-thalamic region. 2. Investigate the impact of combining FUS-BBBO with CED on drug distribution, with a specific focus on the temporal dynamics of drug retention within the target region. MethodsFirstly, we quantitatively assessed how FUS-BBBO coupled with IT and IV altered fluorescent dye (Dextran 2000 kDa and 70 kDa) distribution and concentration in a predetermined striatal-thalamic region in naïve mice. Secondly, we analyzed the pharmacokinetic effects of using FUS mediated BBB disruption coupled with CED by measuring the volume of distribution and time-dependent concentration of the dye. ResultsOur results indicate that IV administration coupled with FUS-BBBO successfully enhances delivery of dye into the pre-defined sonication targets. Conversely, measurable dye in the sonication target was consistently less after IT administration. FUS enhances the distribution volume of dye after CED. Furthermore, a shorter time of residence was observed when CED was coupled with FUS-BBBO application when compared to CED alone. Conclusion1. Based on our findings, IV delivery coupled with FUS-BBBO is a more efficient means for delivery to deep targets (i.e. striatal-thalamic region) within a predefined spatial conformation compared to IT administration. 2. FUS-BBBO increases the volume of distribution (Vd) of dye after CED administration, but results in a shorter time of residence. Whether this finding is reproducible with other classes of agents (e.g., cytotoxic agents, antibodies, viral particles, cellular therapies) needs to be studied.

Preparation of cryopreserved chimeric antigen receptor T cells for the locoreogional delivery to the neural axis

Background aimsIntracranial (IC) locoregional delivery of chimeric antigen receptor (CAR) T cells presents an attractive delivery method to central nervous system tumors. Although IC delivery is actively being employed in early-phase clinical studies, no thaw/wash methods have been published to remove the neurotoxic cryoprotectant dimethyl sulfoxide (DMSO) from CAR T-cell products before IC administration. Thus, the aim of this study was to develop and validate a simple thaw/wash procedure. MethodsWe developed a thaw/wash procedure that consist of product thaw at 37°C, equilibration for 5 min in 1 volume of preservative-free normal saline (PFNS), dilution with an additional 8 volumes of PFNS, removal of DMSO through a washing step, resuspension in 2.0 mL of PFNS and storage in a syringe at 20–25°C. Final formulated products (FPs) were assessed for quality and safety attributes and stability over 3 h from the completion of the thaw. Stability parameters included CAR T-cell viability, transgene surface expression and cytolytic activity. ResultsThe developed procedure reduced the calculated % of DMSO to less than 0.025%. FP cell viability and recovery (versus pre-cryopreservation) were within acceptable specifications (mean viability: 85.3%, range: 83%–88%; total nucleated cell recovery mean: 76.5%, range: 65.4%–82.5%). Other prespecified quality assurance/quality control parameters including appearance/ integrity, sterility and endotoxin level (≤1.0 EU/mL), were also met by all FPs (n = 3). Three hours’ post thaw/wash stability was confirmed. All products maintained cell viability greater than 70% (mean, 80.0%; range, 79%–81%), with no significant change in transgene expression or cytolytic activity of B7-H3-CAR T cells compared with thawed not diluted/washed control CAR T cells. ConclusionsWe have developed a simple thaw/wash procedure to prepare B7-H3-CAR T cells for their locoregional delivery to the neural axis. While we focus here on CAR T cells, the methods could be readily adapted to other cryopreserved immune effector cell products.