Iontophoretic device delivery for the localized treatment of pancreatic ductal adenocarcinoma

Drug delivery to pancreatic tumors is impaired by a unique desmoplastic response and poor tumor vascularization. A drug delivery device capable of overcoming these barriers could provide substantial benefit for patients with pancreatic cancer. In this study, we show that local iontophoretic delivery of folinic acid (leucovorin), fluorouracil, irinotecan, and oxaliplatin (FOLFIRINOX) resulted in better tumor response and tolerability compared with i.v. FOLFIRINOX. Given the low systemic exposure of FOLFIRINOX using iontophoretic delivery, it may be possible to use in combination with systemic delivery to treat micrometastatic disease. Local iontophoretic delivery of cytotoxic agents should be considered as a neoadjuvant approach to improve resection rates and outcome in patients with localized and locally advanced pancreatic cancer

Evaluation of drug loading, pharmacokinetic behavior, and toxicity of a cisplatin-containing hydrogel nanoparticle

Cisplatin is a cytotoxic drug used as a first-line therapy for a wide variety of cancers. However, significant renal and neurological toxicities limits it clinical use. It has been documented that drug toxicities can be mitigated through nanoparticle formulation, while simultaneously increasing tumor accumulation through the enhanced permeation and retention effect. Circulation persistence is a key characteristic for exploiting this effect, and to that end we have developed long-circulating, PEGylated, polymeric hydrogels using the Particle Replication In Non-wetting Templates (PRINT®) platform and complexed cisplatin into the particles (PRINT-Platin). Sustained release was demonstrated, and drug loading correlated to surface PEG density. A PEG Mushroom conformation showed the best compromise between particle pharmacokinetic (PK) parameters and drug loading (16 wt %). While the PK profile of PEG Brush was superior, the loading was poor (2 wt %). Conversely, the drug loading in non-PEGylated particles was better (20 wt %), but the PK was not desirable. We also showed comparable cytotoxicity to cisplatin in several cancer cell lines (non-small cell lung, A549; ovarian, SKOV-3; breast, MDA-MB-468) and a higher MTD in mice (10 mg/kg versus 5 mg/kg). The pharmacokinetic profiles of drug in plasma, tumor, and kidney indicate improved exposure in the blood and tumor accumulation, with concurrent renal protection, when cisplatin was formulated in a nanoparticle. PK parameters were markedly improved: a 16.4-times higher area-under-the-curve (AUC), a reduction in clearance (CL) by a factor of 11.2, and a 4.20-times increase in the volume of distribution (Vd). Additionally, non-small cell lung and ovarian tumor AUC was at least twice that of cisplatin in both models. These findings suggest the potential for PRINT-Platin to improve efficacy and reduce toxicity compared to current cisplatin therapies

Docetaxel-Loaded PLGA Nanoparticles Improve Efficacy in Taxane-Resistant Triple-Negative Breast Cancer

Novel treatment strategies, including nanomedicine, are needed for improving management of triple-negative breast cancer. Patients with triple-negative breast cancer, when considered as a group, have a worse outcome after chemotherapy than patients with breast cancers of other subtypes, a finding that reflects the intrinsically adverse prognosis associated with the disease. The aim of this study was to improve the efficacy of docetaxel by incorporation into a novel nanoparticle platform for the treatment of taxane-resistant triple-negative breast cancer. Rod-shaped nanoparticles encapsulating docetaxel were fabricated using an imprint lithography based technique referred to as Particle Replication in Nonwetting Templates (PRINT). These rod-shaped PLGA-docetaxel nanoparticles were tested in the C3(1)-T-antigen (C3Tag) genetically engineered mouse model (GEMM) of breast cancer that represents the basal-like subtype of triple-negative breast cancer and is resistant to therapeutics from the taxane family. Thi..

EGFR Targeted Theranostic Nanoemulsion for Image-Guided Ovarian Cancer Therapy

Platinum-based therapies are the first line treatments for most types of cancer including ovarian cancer. However, their use is associated with dose-limiting toxicities and resistance. We report initial translational studies of a theranostic nanoemulsion loaded with a cisplatin derivative, myrisplatin and pro-apoptotic agent, C6-ceramide

Evolutionary Instability of Symbiotic Function in Bradyrhizobium japonicum

Bacterial mutualists are often acquired from the environment by eukaryotic hosts. However, both theory and empirical work suggest that this bacterial lifestyle is evolutionarily unstable. Bacterial evolution outside of the host is predicted to favor traits that promote an independent lifestyle in the environment at a cost to symbiotic function. Consistent with these predictions, environmentally-acquired bacterial mutualists often lose symbiotic function over evolutionary time. Here, we investigate the evolutionary erosion of symbiotic traits in Bradyrhizobium japonicum, a nodulating root symbiont of legumes. Building on a previous published phylogeny we infer loss events of nodulation capability in a natural population of Bradyrhizobium, potentially driven by mutation or deletion of symbiosis loci. Subsequently, we experimentally evolved representative strains from the symbiont population under host-free in vitro conditions to examine potential drivers of these loss events. Among Bradyrhizobium genotypes that evolved significant increases in fitness in vitro, two exhibited reduced symbiotic quality, but no experimentally evolved strain lost nodulation capability or evolved any fixed changes at six sequenced loci. Our results are consistent with trade-offs between symbiotic quality and fitness in a host free environment. However, the drivers of loss-of-nodulation events in natural Bradyrhizobium populations remain unknown

Local iontophoretic administration of cytotoxic therapies to solid tumors

Parenteral and oral routes have been the traditional methods of administering cytotoxic agents to cancer patients. Unfortunately, the maximum potential effect of these cytotoxic agents has been limited because of systemic toxicity and poor tumor perfusion. In an attempt to improve the efficacy of cytotoxic agents while mitigating their side effects, we have developed modalities for the localized iontophoretic delivery of cytotoxic agents. These iontophoretic devices were designed to be implanted proximal to the tumor with external control of power and drug flow. Three distinct orthotopic mouse models of cancer and a canine model were evaluated for device efficacy and toxicity. Orthotopic patient-derived pancreatic cancer xenografts treated biweekly with gemcitabine via the device for 7 weeks experienced a mean log2 fold change in tumor volume of −0.8 compared to a mean log2 fold change in tumor volume of 1.1 for intravenous (IV) gemcitabine, 3.0 for IV saline, and 2.6 for device saline groups. The weekly coadministration of systemic cisplatin therapy and transdermal device cisplatin therapy significantly increased tumor growth inhibition and doubled the survival in two aggressive orthotopic models of breast cancer. The addition of radiotherapy to this treatment further extended survival. Device delivery of gemcitabine in dogs resulted in more than 7-fold difference in local drug concentrations and 25-fold lower systemic drug levels than the IV treatment. Overall, these devices have potential paradigm shifting implications for the treatment of pancreatic, breast, and other solid tumors

Effect of angiotensin-converting enzyme inhibitor and angiotensin receptor blocker initiation on organ support-free days in patients hospitalized with COVID-19

IMPORTANCE Overactivation of the renin-angiotensin system (RAS) may contribute to poor clinical outcomes in patients with COVID-19. Objective To determine whether angiotensin-converting enzyme (ACE) inhibitor or angiotensin receptor blocker (ARB) initiation improves outcomes in patients hospitalized for COVID-19. DESIGN, SETTING, AND PARTICIPANTS In an ongoing, adaptive platform randomized clinical trial, 721 critically ill and 58 non–critically ill hospitalized adults were randomized to receive an RAS inhibitor or control between March 16, 2021, and February 25, 2022, at 69 sites in 7 countries (final follow-up on June 1, 2022). INTERVENTIONS Patients were randomized to receive open-label initiation of an ACE inhibitor (n = 257), ARB (n = 248), ARB in combination with DMX-200 (a chemokine receptor-2 inhibitor; n = 10), or no RAS inhibitor (control; n = 264) for up to 10 days. MAIN OUTCOMES AND MEASURES The primary outcome was organ support–free days, a composite of hospital survival and days alive without cardiovascular or respiratory organ support through 21 days. The primary analysis was a bayesian cumulative logistic model. Odds ratios (ORs) greater than 1 represent improved outcomes. RESULTS On February 25, 2022, enrollment was discontinued due to safety concerns. Among 679 critically ill patients with available primary outcome data, the median age was 56 years and 239 participants (35.2%) were women. Median (IQR) organ support–free days among critically ill patients was 10 (–1 to 16) in the ACE inhibitor group (n = 231), 8 (–1 to 17) in the ARB group (n = 217), and 12 (0 to 17) in the control group (n = 231) (median adjusted odds ratios of 0.77 [95% bayesian credible interval, 0.58-1.06] for improvement for ACE inhibitor and 0.76 [95% credible interval, 0.56-1.05] for ARB compared with control). The posterior probabilities that ACE inhibitors and ARBs worsened organ support–free days compared with control were 94.9% and 95.4%, respectively. Hospital survival occurred in 166 of 231 critically ill participants (71.9%) in the ACE inhibitor group, 152 of 217 (70.0%) in the ARB group, and 182 of 231 (78.8%) in the control group (posterior probabilities that ACE inhibitor and ARB worsened hospital survival compared with control were 95.3% and 98.1%, respectively). CONCLUSIONS AND RELEVANCE In this trial, among critically ill adults with COVID-19, initiation of an ACE inhibitor or ARB did not improve, and likely worsened, clinical outcomes. TRIAL REGISTRATION ClinicalTrials.gov Identifier: NCT0273570