Top Ten Tips Palliative Care Clinicians Should Know About Designing a Clinical Trial in Palliative Care.

The palliative care field is experiencing substantive growth in clinical trial-based research. Randomized controlled trials provide the necessary rigor and conditions for assessing a treatment's efficacy in a controlled population. It is therefore important that a trial is meticulously designed from the outset to ensure the integrity of the ultimate results. In this article, our team discusses ten tips on clinical trial design drawn from collective experiences in the field. These ten tips cover a range of topics that can prove challenging in trial design, from developing initial methodologies to planning sample size and powering the trial, as well as collaboratively navigating the ethical issues of trial initiation and implementation as a cohesive team. We aim to help new researchers design sound trials and continue to grow the evidence base for our specialty. The guidance provided here can be used independently or in addition to the ten tips provided by this team in a separate article focused on what palliative care clinicians should know about interpreting a clinical trial.

Top Ten Tips Palliative Care Clinicians Should Know About Interpreting a Clinical Trial.

Evidence-based practice is foundational to high-quality palliative care delivery. However, the clinical trials that compose the evidence base are often methodologically imperfect. Applying their conclusions without critical application to the clinical practice context can harm patients. The tips provided can help clinicians infer judiciously from clinical trial results and avoid credulously accepting findings without critique. We suggest that statistical and mathematical expertise is unnecessary, but rather a keen curiosity about investigators' rationale for certain design choices and how these choices can affect results is key. For a more comprehensive understanding of clinical trials, this article can be used with the authors' corresponding ten tips article that focuses on designing a clinical trial.

Cannabidiol oil or placebo in advanced cancer-disease progression and survival: a secondary analysis.

OBJECTIVES: Medical cannabinoids have become increasingly popular over the last decade. Preclinical trials suggest cannabinoids, for example, cannabidiol (CBD), may provide an anticancer effect; however, good-quality clinical information supporting this is lacking. We assessed the effect of CBD treatment on disease progression and survival in patients enrolled in a study of CBD versus placebo for symptom management in patients with advanced cancer (MEDCAN-1). METHODS: We reviewed the clinical records of all patients enrolled in the MEDCAN-1 Study (CBD vs placebo) at days 14, 28 and 56 of study follow-up, for evidence of disease progression. The proportion of participants with disease progression by treatment arm at each time point was compared, as was survival between both groups from study entry to the censor date (end of study period) and the effect of treatment arm and disease progression status on survival. RESULTS: Of the 135 patient records assessed, 128 were included in the final analysis. 36% (n=46) had progressive disease documented at day 28, rising to 49.2% (n=63) by day 56. No significant difference in disease progression was noted between the two groups at days 14 (p=0.33), 28 (p=0.67) or 56 (p=0.50). There was no difference in survival between both groups from study entry to censor date (p=0.38). Disease progression at day 14 was highly predictive of mortality (p<0.001). CONCLUSIONS: In this substudy analysis, treatment with CBD oil did not affect disease progression or survival over the course of 56 days in patients with advanced cancer.

Palliative radiotherapy and the introduction of a Rapid Access Palliative Clinic in a national radiation oncology network.

BACKGROUND: Palliative radiotherapy (PRT) is commonly used to treat symptoms of advanced cancer. PRT has been associated with elevated 30-day mortality (30DM). A Rapid Access Palliative Clinic (RAPC) can streamline the treatment process for patients receiving treatment. AIMS: We reviewed the PRT practices in a radiation oncology network in Ireland, and the implementation of a RAPC. Patient outcomes were assessed to inform future treatment decisions. METHODS: A retrospective review of all patients who received PRT over 6 months in 2018 in St. Luke's Radiation Oncology Network (SLRON) was undertaken. We assessed 30DM rates, demographics and referral to specialist palliative care (SPC) services. Subsequently, a retrospective analysis was conducted of a RAPC which ran for 6 months from 2019 to 2020. We assessed treatment data and mortality. RESULTS: Over 6 months, 645 patients commenced PRT in the SLRON. The 30DM for this cohort was 15.8% (n = 102), with most patients having lung primaries. Of the 30DM cohort, only 55% (n = 56) were referred to SPC services and only 26.4% (n = 27) had performance status recorded. Over 6 months, 40 patients attended 28 RAPCs. Of these, 88% (n = 35) received PRT. Single fraction therapy was utilised in 60% and 48% of patients underwent CT simulation and treatment on the same day. Ultimately, 75% of patients received SPC referral. CONCLUSIONS: Referral rates to SPC services and documentation of performance status were low in our 30DM retrospective review cohort. The RAPC facilitated quick treatment turnaround, fewer hospital visits and referral to SPC services.

Chronic tympanic membrane perforation repair with a collagen-based scaffold: An in vivo model.

OBJECTIVE: The aim of this study was to assess the in vivo efficacy of a novel regenerative collagen-based scaffold developed by the Royal College of Surgeons in Ireland in a chronic tympanic membrane perforation (TMP) using a chinchilla model. METHODS: Bilateral TMPs were induced in 17 mixed gender chinchillas using tympanic membrane resection followed by a mixture of topical Mitomycin C and dexamethasone for 3 days. These were monitored with weekly otoscopy for 8 weeks. Animals were excluded if signs of infection developed in the follow up period (n = 8). At 8 weeks, intervention began and 18 TMPs were assigned to either treatment with the collagen-based scaffold (treated group) or spontaneous healing (control group). Animals were euthanized 6 weeks post-intervention. Otoscopic imaging and auditory brain response (ABR) were conducted at baseline, 8 weeks post-TMP induction and 6 weeks post-intervention. All TMPs were then evaluated at 6 weeks post-intervention and bullae underwent histologic evaluation. RESULTS: At 6 weeks post-intervention, otoscopic imaging demonstrated various degrees of healing in the treated ears. The treated group was noted to have an increased rate of healing when compared to the control group. Histologic evaluation demonstrated a variation in the degree of perforation healing within groups, with some animals in the treated group showing high levels of perforation healing. At 8 weeks after the TMP procedure, most of the animals had worsened hearing response. At 6-week post the collagen-based scaffold treatment, about 50 % (4/8) of the treated ears had improved in hearing response as compared to those of non-treated ears. CONCLUSION: Given the initial histologic evidence of partial healing in scaffold-treated ears, the post-intervention period should be extended to monitor the potential for complete healing. Given the overall positive findings related to healing with the scaffold-treated ears, this material warrants further investigation.

Targeted Therapies for Kirsten Rat Sarcoma (KRAS) G12C Mutant Metastatic Non-Small-Cell Lung Cancers.

Non-small-cell lung cancer (NSCLC) is a prevalent and often fatal malignancy. Advancements in targeted therapies have improved outcomes for NSCLC patients in the last decade. Kirsten rat sarcoma virus (KRAS) is a commonly mutated oncogene in NSCLC, contributing to tumorigenesis and proliferation. Though classically difficult to target, recently developed KRAS G12C inhibitors (sotorasib and adagrasib) have now overcome this therapeutic hurdle. We discuss the evidence for these medications, their pitfalls and adverse effects, as well as future directions in this space. Though these medications demonstrate substantial response rates in a heavily pre-treated advanced NSCLC cohort, as phase-3 evidence does not yet demonstrate an overall survival benefit versus standard-of-care chemotherapy, docetaxel. Additionally, these medications appear to have a negative interaction in combination with immunotherapies, with substantially greater hepatotoxicity rates observed. Despite this, it is undeniable that these medications represent an important advancement in targeted and personalised oncological treatment. Current and future trials assessing these medications in combination and through sequencing strategies will likely yield further clinically meaningful outcomes to guide treatment in this patient cohort.

Vedolizumab-induced acute interstitial nephritis with failure of steroid prophylaxis on vedolizumab rechallenge.

Acute interstitial nephritis (AIN) is a common cause of acute kidney injury and renal failure. It is typically drug induced but can also be idiopathic or secondary to chronic infective or inflammatory conditions. Recent case reports suggest vedolizumab can be a causative agent for AIN. We report the case of a young man who presented with renal failure, fevers and constitutional symptoms. He had a complex history of refractory ulcerative colitis, prior colectomy and ileo-pouch-anal anastomosis with recurrent pouchitis. He had been receiving regular vedolizumab infusions for 6 months by the time of his presentation. A renal biopsy 4 months into his follow-up demonstrated AIN. Steroid prophylaxis with vedolizumab was trialled but ultimately failed, with worsening AIN and incomplete renal function recovery. To our knowledge, this is the first case of vedolizumab-induced AIN demonstrating a failure of steroid prophylaxis to prevent recurrence of AIN following vedolizumab rechallenge.

Development of tissue-engineered tracheal scaffold with refined mechanical properties and vascularisation for tracheal regeneration.

Introduction: Attempted tracheal replacement efforts thus far have had very little success. Major limiting factors have been the inability to efficiently re-vascularise and mimic the mechanical properties of native tissue. The major objective of this study was to optimise a previously developed collagen-hyaluronic acid scaffold (CHyA-B), which has shown to facilitate the growth of respiratory cells in distinct regions, as a potential tracheal replacement device. Methods: A biodegradable thermoplastic polymer was 3D-printed into different designs and underwent multi-modal mechanical assessment. The 3D-printed constructs were incorporated into the CHyA-B scaffolds and subjected to in vitro and ex vivo vascularisation. Results: The polymeric backbone provided sufficient strength to the CHyA-B scaffold, with yield loads of 1.31-5.17 N/mm and flexural moduli of 0.13-0.26 MPa. Angiogenic growth factor release (VEGF and bFGF) and angiogenic gene upregulation (KDR, TEK-2 and ANG-1) was detected in composite scaffolds and remained sustainable up to 14 days. Confocal microscopy and histological sectioning confirmed the presence of infiltrating blood vessel throughout composite scaffolds both in vitro and ex vivo. Discussion: By addressing both the mechanical and physiological requirements of tracheal scaffolds, this work has begun to pave the way for a new therapeutic option for large tracheal defects.

Engineering Large Airways.

A key issue facing trachea replacement attempts has been the discrepancy of the mechanical properties between the native tracheal tissue and that of the replacement construct; this difference is often one of the major causes for implant failure in vivo and within clinical efforts. The trachea is composed of distinct structural regions, with each component fulfilling a different role in maintaining overall tracheal stability. The trachea's horseshoe-shaped hyaline cartilage rings, smooth muscle and annular ligament collectively produce an anisotropic tissue that allows for longitudinal extensibility and lateral rigidity. Therefore, any tracheal substitute must be mechanically robust in order to withstand intra-thoracic pressure changes that occur during respiration. Conversely, they must also be able to deform radially to allow for changes in the cross-sectional area during coughing and swallowing. These complicated native tissue characteristics, coupled with a lack of standardised protocols to accurately quantify tracheal biomechanics as guidance for implant design, constitute a significant hurdle for tracheal biomaterial scaffold fabrication. This chapter aims to highlight the pressure forces exerted on the trachea and how they can influence tracheal construct design and also the biomechanical properties of the three main components of the trachea and how to mechanically assess them.

Tissue engineering and regenerative medicine strategies for the repair of tympanic membrane perforations.

Despite the high success rate of autologous grafts in tympanic membrane repair, clinical alternatives are required for the closure of unresponsive chronic perforations that can lead to recurring infection and hearing loss. Tissue engineering and regenerative medicine approaches have emerged as another strategy to repair the eardrum, in addition to negating the need for donor tissue harvest and related surgical iatrogenicities. This review highlights the main approaches using biomaterials, growth factors, and cell therapies towards the healing of complex TM perforations. In addition, we discuss the challenges and advances for the development of reliable animal models, which will allow the optimisation and development of novel techniques. Finally, we indicate technologies that are currently used clinically and others that are closer to the market. The advances here discussed on tissue engineering and regenerative medicine strategies applied to the field of TM perforations will allow otologists, surgeons, and researchers to better bring novel technologies to the bedside as well as to develop new ones.

Development and clinical translation of tubular constructs for tracheal tissue engineering: a review.

Effective restoration of extensive tracheal damage arising from cancer, stenosis, infection or congenital abnormalities remains an unmet clinical need in respiratory medicine. The trachea is a 10-11 cm long fibrocartilaginous tube of the lower respiratory tract, with 16-20 tracheal cartilages anterolaterally and a dynamic trachealis muscle posteriorly. Tracheal resection is commonly offered to patients suffering from short-length tracheal defects, but replacement is required when the trauma exceeds 50% of total length of the trachea in adults and 30% in children. Recently, tissue engineering (TE) has shown promise to fabricate biocompatible tissue-engineered tracheal implants for tracheal replacement and regeneration. However, its widespread use is hampered by inadequate re-epithelialisation, poor mechanical properties, insufficient revascularisation and unsatisfactory durability, leading to little success in the clinical use of tissue-engineered tracheal implants to date. Here, we describe in detail the historical attempts and the lessons learned for tracheal TE approaches by contextualising the clinical needs and essential requirements for a functional tracheal graft. TE manufacturing approaches explored to date and the clinical translation of both TE and non-TE strategies for tracheal regeneration are summarised to fully understand the big picture of tracheal TE and its impact on clinical treatment of extensive tracheal defects.

A Tissue-Engineered Tracheobronchial In Vitro Co-Culture Model for Determining Epithelial Toxicological and Inflammatory Responses.

Translation of novel inhalable therapies for respiratory diseases is hampered due to the lack of in vitro cell models that reflect the complexity of native tissue, resulting in many novel drugs and formulations failing to progress beyond preclinical assessments. The development of physiologically-representative tracheobronchial tissue analogues has the potential to improve the translation of new treatments by more accurately reflecting in vivo respiratory pharmacological and toxicological responses. Herein, advanced tissue-engineered collagen hyaluronic acid bilayered scaffolds (CHyA-B) previously developed within our group were used to evaluate bacterial and drug-induced toxicity and inflammation for the first time. Calu-3 bronchial epithelial cells and Wi38 lung fibroblasts were grown on either CHyA-B scaffolds (3D) or Transwell® inserts (2D) under air liquid interface (ALI) conditions. Toxicological and inflammatory responses from epithelial monocultures and co-cultures grown in 2D or 3D were compared, using lipopolysaccharide (LPS) and bleomycin challenges to induce bacterial and drug responses in vitro. The 3D in vitro model exhibited significant epithelial barrier formation that was maintained upon introduction of co-culture conditions. Barrier integrity showed differential recovery in CHyA-B and Transwell® epithelial cultures. Basolateral secretion of pro-inflammatory cytokines to bacterial challenge was found to be higher from cells grown in 3D compared to 2D. In addition, higher cytotoxicity and increased basolateral levels of cytokines were detected when epithelial cultures grown in 3D were challenged with bleomycin. CHyA-B scaffolds support the growth and differentiation of bronchial epithelial cells in a 3D co-culture model with different transepithelial resistance in comparison to the same co-cultures grown on Transwell® inserts. Epithelial cultures in an extracellular matrix like environment show distinct responses in cytokine release and metabolic activity compared to 2D polarised models, which better mimic in vivo response to toxic and inflammatory stimuli offering an innovative in vitro platform for respiratory drug development.

Repositioning Natural Antioxidants for Therapeutic Applications in Tissue Engineering.

Although a large panel of natural antioxidants demonstrate a protective effect in preventing cellular oxidative stress, their low bioavailability limits therapeutic activity at the targeted injury site. The importance to deliver drug or cells into oxidative microenvironments can be realized with the development of biocompatible redox-modulating materials. The incorporation of antioxidant compounds within implanted biomaterials should be able to retain the antioxidant activity, while also allowing graft survival and tissue recovery. This review summarizes the recent literature reporting the combined role of natural antioxidants with biomaterials. Our review highlights how such functionalization is a promising strategy in tissue engineering to improve the engraftment and promote tissue healing or regeneration.

The Fabrication and in vitro Evaluation of Retinoic Acid-Loaded Electrospun Composite Biomaterials for Tracheal Tissue Regeneration.

Although relatively rare, major trauma to the tracheal region of the airways poses a significant clinical challenge with few effective treatments. Bioengineering and regenerative medicine strategies have the potential to create biocompatible, implantable biomaterial scaffolds, with the capacity to restore lost tissue with functional neo-trachea. The main goal of this study was to develop a nanofibrous polycaprolactone-chitosan (PCL-Chitosan) scaffold loaded with a signaling molecule, all-trans retinoic acid (atRA), as a novel biomaterial approach for tracheal tissue engineering. Using the Spraybase® electrospinning platform, polymer concentration, solvent selection, and instrument parameters were optimized to yield a co-polymer with nanofibers of 181-197 nm in diameter that mimicked tracheobronchial tissue architecture. Thereafter, scaffolds were assessed for their biocompatibility and capacity to induce mucociliary functionalization using the Calu-3 cell line. PCL-Chitosan scaffolds were found to be biocompatible in nature and support Calu-3 cell viability over a 14 day time period. Additionally, the inclusion of atRA did not compromise Calu-3 cell viability, while still achieving an efficient encapsulation of the signaling molecule over a range of atRA concentrations. atRA release from scaffolds led to an increase in mucociliary gene expression at high scaffold loading doses, with augmented MUC5AC and FOXJ1 detected by RT-PCR. Overall, this scaffold integrates a synthetic polymer that has been used in human tracheal stents, a natural polymer generally regarded as safe (GRAS), and a drug with decades of use in patients. Coupled with the scalable nature of electrospinning as a fabrication method, all of these characteristics make the biomaterial outlined in this study amenable as an implantable device for an unmet clinical need in tracheal replacement.

Tissue Engineering: Understanding the Role of Biomaterials and Biophysical Forces on Cell Functionality Through Computational and Structural Biotechnology Analytical Methods.

Within the past 25 years, tissue engineering (TE) has grown enormously as a science and as an industry. Although classically concerned with the recapitulation of tissue and organ formation in our body for regenerative medicine, the evolution of TE research is intertwined with progress in other fields through the examination of cell function and behaviour in isolated biomimetic microenvironments. As such, TE applications now extend beyond the field of tissue regeneration research, operating as a platform for modifiable, physiologically-representative in vitro models with the potential to improve the translation of novel therapeutics into the clinic through a more informed understanding of the relevant molecular biology, structural biology, anatomy, and physiology. By virtue of their biomimicry, TE constructs incorporate features of extracellular macrostructure, molecular adhesive moieties, and biomechanical properties, converging with computational and structural biotechnology advances. Accordingly, this mini-review serves to contextualise TE for the computational and structural biotechnology reader and provides an outlook on how the disciplines overlap with respect to relevant advanced analytical applications.

Emerging Nanomedicine Therapies to Counter the Rise of Methicillin-Resistant Staphylococcus aureus.

In a recent report, the World Health Organisation (WHO) classified antibiotic resistance as one of the greatest threats to global health, food security, and development. Methicillin-resistant Staphylococcus aureus (MRSA) remains at the core of this threat, with persistent and resilient strains detectable in up to 90% of S. aureus infections. Unfortunately, there is a lack of novel antibiotics reaching the clinic to address the significant morbidity and mortality that MRSA is responsible for. Recently, nanomedicine strategies have emerged as a promising therapy to combat the rise of MRSA. However, these approaches have been wide-ranging in design, with few attempts to compare studies across scientific and clinical disciplines. This review seeks to reconcile this discrepancy in the literature, with specific focus on the mechanisms of MRSA infection and how they can be exploited by bioactive molecules that are delivered by nanomedicines, in addition to utilisation of the nanomaterials themselves as antibacterial agents. Finally, we discuss targeting MRSA biofilms using nano-patterning technologies and comment on future opportunities and challenges for MRSA treatment using nanomedicine.

Retinoic Acid-Loaded Collagen-Hyaluronate Scaffolds: A Bioactive Material for Respiratory Tissue Regeneration.

Clinical interventions for extensive tissue injury to the larger airways remain limited. Recently, respiratory tissue engineering strategies have emerged with a variety of biomimetic materials and tissue constructs to address these limitations, though rapid epithelialization of the construct with mucociliary function is still largely unresolved. The overall objective of this study was to manufacture an all-trans retinoic acid (atRA)-loaded bilayered collagen-hyaluronate (atRA-B) scaffold as a platform technology for tracheal tissue regeneration. atRA-loaded scaffolds were fabricated using a customized lyophilization process and characterized for drug loading and release properties using HPLC, followed by validation of their bioactivity using human primary tracheobronchial epithelial cells. atRA-loaded materials were reproducibly manufactured and exhibited the release of atRA following their hydration over 8-28 h that was significantly affected by collagen cross-linking. An optimal formulation consisting of 10 µg/mL atRA in a collagen-hyaluronate suspension to manufacture the scaffold film layer was identified and used to develop the atRA-B scaffold. Immunofluorescence studies and RT-PCR revealed that the atRA-loaded biomaterials increased the expression of two epithelial markers of mucociliary differentiation, MUC5AC and ß-tubulin IV, via upregulation of MUC5AC and FOXJ1 genes, both in epithelial monoculture and in a 3D scaffold coculture system with lung fibroblasts. Overall, this study has demonstrated that the atRA-B scaffold can enhance functional epithelialization in primary tracheobronchial cells and can potentially pioneer the development of a novel and biocompatible device to address a currently unmet clinical need in tracheal replacement.

The development of a tissue-engineered tracheobronchial epithelial model using a bilayered collagen-hyaluronate scaffold.

Today, chronic respiratory disease is one of the leading causes of mortality globally. Epithelial dysfunction can play a central role in its pathophysiology. The development of physiologically-representative in vitro model systems using tissue-engineered constructs might improve our understanding of epithelial tissue and disease. This study sought to engineer a bilayered collagen-hyaluronate (CHyA-B) scaffold for the development of a physiologically-representative 3D in vitro tracheobronchial epithelial co-culture model. CHyA-B scaffolds were fabricated by integrating a thin film top-layer into a porous sub-layer with lyophilisation. The film layer firmly connected to the sub-layer with delamination occurring at stresses of 12-15 kPa. Crosslinked scaffolds had a compressive modulus of 1.9 kPa and mean pore diameters of 70 µm and 80 µm, depending on the freezing temperature. Histological analysis showed that the Calu-3 bronchial epithelial cell line attached and grew on CHyA-B with adoption of an epithelial monolayer on the film layer. Immunofluorescence and qRT-PCR studies demonstrated that the CHyA-B scaffolds facilitated Calu-3 cell differentiation, with enhanced mucin expression, increased ciliation and the formation of intercellular tight junctions. Co-culture of Calu-3 cells with Wi38 lung fibroblasts was achieved on the scaffold to create a submucosal tissue analogue of the upper respiratory tract, validating CHyA-B as a platform to support co-culture and cellular organisation reminiscent of in vivo tissue architecture. In summary, this study has demonstrated that CHyA-B is a promising tool for the development of novel 3D tracheobronchial co-culture in vitro models with the potential to unravel new pathways in drug discovery and drug delivery.

Respiratory Tissue Engineering: Current Status and Opportunities for the Future.

Currently, lung disease and major airway trauma constitute a major global healthcare burden with limited treatment options. Airway diseases such as chronic obstructive pulmonary disease and cystic fibrosis have been identified as the fifth highest cause of mortality worldwide and are estimated to rise to fourth place by 2030. Alternate approaches and therapeutic modalities are urgently needed to improve clinical outcomes for chronic lung disease. This can be achieved through tissue engineering of the respiratory tract. Interest is growing in the use of airway tissue-engineered constructs as both a research tool, to further our understanding of airway pathology, validate new drugs, and pave the way for novel drug therapies, and also as regenerative medical devices or as an alternative to transplant tissue. This review provides a concise summary of the field of respiratory tissue engineering to date. An initial overview of airway anatomy and physiology is given, followed by a description of the stem cell populations and signaling processes involved in parenchymal healing and tissue repair. We then focus on the different biomaterials and tissue-engineered systems employed in upper and lower respiratory tract engineering and give a final perspective of the opportunities and challenges facing the field of respiratory tissue engineering.