Sc Administration Research Articles

750-P: Novel Approach for Development of Oral GLP-1 Receptor Agonist with Superior Bioavailability and Antidiabetic Efficacy

While glucagon-like peptide 1 receptor agonists (GLP-1 RAs) are highly effective at lowering HbA1c, currently available GLP-1 RA delivery options are suboptimal; SC administrations hinder patient adherence and oral administrations have lower bioavailability due to enzymatic instability and insufficient gastrointestinal absorption. A novel approach to deliver GLP-1 RAs with superior bioavailability and better patient adherence would further improve the antidiabetes efficacy of GLP-1 RAs. Hence, this study assesses an oral formulation facilitating intestinal absorption of DD02S, a new GLP-1RA. Biological activities, gastrointestinal stabilities and Caco-2 permeability study of DD02S were performed in vitro. The in vivo efficacy of the oral formulation was evaluated by intraduodenal injection in rats. DD02S was formulated as enteric coated tablets and orally administered in dogs. Pharmacological efficacy was demonstrated by repeated dosing in db/db mice. DD02S was designed to introduce a ligand and fatty acid to facilitate cellular uptake via intestinal transporters, increase enzyme stability, and enable reversible plasma protein binding without loss of potency. The oral formulation enhanced the intestinal stability as well as permeation via trans and paracellular routes. The increased intestinal absorption was confirmed by intraduodenal injection in rats. Following the oral administration of the enteric coated tablets to dogs, the mean bioavailability ranged from 5.0-10.1% with variability of 78-117% and pharmacokinetic parameters were suitable for once daily oral dosing. In the antidiabetes efficacy study of DD02S, significant reduction of HbA1c was observed in a dose-dependent manner. This study demonstrates the potential antidiabetes efficacy of DD02S with once daily oral dosing. Our novel approach for oral delivery is promising to development of other oral peptide therapeutics. Disclosure E.Park: Employee; D&D Pharmatech. O.Jeon: Employee; D&D Pharmatech. J.Park: Employee; D&D Pharmatech. J.Choi: Employee; D&D Pharmatech. J.Shin: Employee; D&D Pharmatech. S.Lim: Board Member; D&D pharmatech. S.Park: Board Member; D&D Pharmatech. S.Lee: Board Member; D&D Pharmatech.

Optimization of Renal Delivery of an MMP2‐inhibitory Peptide Delivered Using the Elastin‐like Polypeptide Carrier

Chronic kidney disease (CKD) is a global health issue associated with the development of renal fibrosis. Renal fibrosis is caused by the excessive deposition of extracellular matrix (ECM) leading to organ failure and is the final common pathway in CKD. ECM homeostasis and degradation are mediated by matrix metalloproteinases (MMPs). Imbalances in MMP activity exacerbate renal damage and fibrosis. While increased expression of some MMPs can be anti‐fibrotic, other MMPs, such as MMP2, activate pro‐inflammatory and fibrotic chemokines and cytokines. Our group has developed an MMP2 inhibitory biologic by fusing an MMP2 inhibitory peptide to a protein biopolymer (ELP‐MMP2i). We hypothesize that ELP‐MMP2i will accumulate in the kidney after systemic administration and reduce or reverse the effects of renal fibrosis. ELP‐MMP2i has potent MMP2 inhibitory activity in vitro (IC50 = 1.1 mM). A pilot study utilizing continuous infusion of ELP‐MMP2i demonstrated reduced proteinuria and albuminuria in a hypertension induced glomerulosclerosis rat model (Dahl Salt Sensitive Rat). The aim of the current study was to optimize the renal delivery of ELP‐MMP2i. Three ELP‐MMP2i proteins using ELP domains of varying molecular weights (26 kDa, 50 kDa, and 99 kDa) were constructed. Pharmacokinetics and biodistribution of these proteins were determined following iv or sc injections (600 nmol/kg) in Sprague Dawley Rats (n= 4/group). The plasma clearance following an iv injection was inversely proportional to the molecular weight, and half‐lives were 0.4, 0.6, and 1.1 hours for the 26, 50, and 99 kDa proteins respectively (Figure A3). Similar results were observed with sc administration, with the smallest protein exhibiting the fastest absorption and the highest peak plasma levels (400 nM, 240 nM, and 180 nM peak plasma, respectively; Figure B2). Bioavailability was 55.3, 25.1, and 16.7% for 26, 50, and 99 kDa proteins respectively following sc administration. Both iv and sc injections exhibited significant deposition in the kidney (Figures A1 & B1), and an inverse correlation between protein size and renal tissue concentrations of 6.2 ± 1.9, 3.6 ± 0.2, and 2.5 ± 0.4 mM renal concentrations for the 26, 50, and 99 kDa proteins, respectively, following iv administration (two‐way ANOVA p<0.0001 Figure A2), and 2.0 ± 0.7, 0.6 ± 0.1, and 0.5 ± 0.1 mM renal concentrations following sc injections (two‐way ANOVA p<0.0001, Figure B2). To further elucidate the pharmacokinetic properties of the protein in a model with renal injury and to test the effects of various doses, Dahl Salt Sensitive rats on an 8% NaCl diet were given a daily sc injections of 300 nmol/kg, 600 nmol/kg or 1,200 nmol/kg of the smallest ELP‐MMP2i peptide (n=3/group) for 7 days. ELP‐MMP2i accumulated almost exclusively in the kidneys with renal concentrations of 7.1 ± 0.3, 12.9 ± 1.2, and 25.0 ± 2.8 mM (p<0.0001, two‐way ANOVA) following doses of 300, 600, and 1,200 nmol/kg/day respectively). These studies revealed that the smallest 26 kDa ELP‐MMP2i protein achieved the best balance of bioavailability and renal deposition. The results indicate that therapeutic doses of ELP‐MMP2i above the IC50can be achieved by daily sc administration.

Solutions à la pénurie de médecins de famille

The disposition and tissue distribution of angiopeptin, a long-acting octapeptide analogue of somatostatin, were studied in rats following single iv and sc administration of the drug. Similar plasma levels and excretion values of angiopeptin were observed by using radioimmunoassay and radiolabeling techniques. Angiopeptin was absorbed fairly rapidly, with a mean peak plasma level of 25 +/- 4.1 ng/ml at 10-15 min after administration. The kinetics of angiopeptin following sc administration closely resembled those following iv administration due to rapid absorption. The pharmacokinetics of angiopeptin can be described by a two-compartment model. The plasma half-life of the drug ranged from 2.6-2.9 hr when administered sc and 1.98-2.5 hr when given iv. Distribution of angiopeptin was rapid, with the highest concentration appearing in the liver. Half-lives in the liver and bile were short. Most of the drug was excreted in the feces via the bile, while approximately 10% was excreted in the urine. Angiopeptin was also found to be secreted in the saliva. TLC and HPLC of blood, urine, feces, and bile samples did not reveal the presence of any metabolites. In conclusion, the in vivo fate of angiopeptin is characterized by little or no hepatic metabolism and rapid biliary excretion.

Neuroprotective Effects of Myrtenal in an Experimental Model of Dementia Induced in Rats.

There is growing attention on natural substances capable of stimulating the cholinergic system and of exerting antioxidant effects, as potential therapeutic agents in Alzheimer’s disease (AD). The aim of the present study is to evaluate the expected neuroprotective mechanisms of myrtenal (M) in an experimental model of dementia in rats. Dementia was induced in male Wistar rats by scopolamine (Sc) administration (0.1 mg/kg for 8 days and 20.0 mg/kg on day 9). The animals were divided into 5 groups (1) Controls; (2) Sc; (3) Sc + Myrtenal (40 mg/kg), (4) Sc + Galantamine (1 mg/kg); (5) Sc + Lipoic acid (30 mg/kg). Changes in recognition memory and habituation were evaluated via the Novel Object Recognition and Open Field tests. Acetylcholinesterase (AChE) activity, ACh levels, and changes in oxidative status of the brain were measured biochemically. The histological changes in two brain regions—cortex and hippocampus, were evaluated qualitatively and quantitatively. Myrtenal improved recognition memory and habituation, exerted antioxidant effects and significantly increased ACh brain levels. Histologically, the neuroprotective capacity of myrtenal was also confirmed. For the first time, we have demonstrated the neuroprotective potential of myrtenal in an experimental model of dementia. Our study provides proof-of-concept for the testing of myrtenal, in association with standard of care treatments, in patients affected by cognitive decline.

Real-world dosing characteristics and utilization of parenteral treprostinil in the outpatient setting.

Real‐world dosing and titration of parenteral (subcutaneous, SC; intravenous, IV) prostacyclin, a mainstay of pulmonary arterial hypertension (PAH) treatment, is not always consistent with prescribing information or randomized trials and has yet to be adequately characterized. The current study describes real‐world outpatient dosing and titration patterns over time, in PAH patients initiated on SC or IV treprostinil. A longitudinal, cross‐sectional analysis of medication shipment records from US specialty pharmacy services between 2009 and 2018 was conducted to determine dosing and titration patterns of SC or IV treprostinil in the outpatient setting beginning with the patient's first shipment. The sample for analysis included shipment records for 2647 patients (IV = 1040, SC = 1607). Although more patients were started on SC treprostinil than IV, median initial outpatient IV treprostinil dose (11 ng/kg/min at month on therapy one [MOT1]) was consistently and statistically significantly higher than initial outpatient SC dose (7.5 ng/kg/min at MOT1; p < 0.01). However, the SC treprostinil dose acceleration rate (DAR) was more aggressive from MOT1 to MOT6, MOT12, and MOT24, leading to a higher dose achieved at later timepoints. All between‐group DAR differences were statistically significant (p < 0.001). This study provides evidence that real‐world prescribing patterns of parenteral treprostinil in the outpatient setting differs from dosing described in pivotal trials, with important differences between SC and IV administration. Although initial outpatient IV treprostinil dosing was higher, SC titration was accelerated more aggressively and a higher dose was achieved by MOT3 suggesting that factors specific to SC administration (e.g., site pain) may not limit dosing and titration as previously thought.

OPTIMIZING THE PHARMACODYNAMICS AND EVALUATING CARDIOGENIC EFFECTS OF THE INJECTABLE ANESTHETIC ALFAXALONE IN PRAIRIE RATTLESNAKES (CROTALUS VIRIDIS)

North American vipers are commonly housed in zoological institutions or studied as free-ranging populations. Because of their venomous predatory and defensive mechanism, sedation or anesthesia is frequently employed to facilitate safe handling and medical procedures, especially of the head. A new formulation of alfaxalone with proprietary preservatives was recently approved and indexed for 28-d use post-vial puncture. Pharmacodynamic effects of alfaxalone in its prior formulation have been researched in nonvenomous species, but the optimal dose and route of administration in vipers have not been reported. In part one, 10 prairie rattlesnakes (Crotalus viridis) participated in a complete four-route crossover study evaluating 20 mg/kg alfaxalone administered intracoelomically (ICo), SC cranial to the heart, IM cranial to the heart, and IV in the ventral coccygeal vein. HR significantly decreased from baseline during IV (P= 0.024), IM (P= 0.024), and SC (P= 0.028) administration. Respiratory rate significantly decreased following alfaxalone delivered IV (P = 0.027). Time to first effects was significantly faster in IV compared with IM (P= 0.01), SC (P= 0.001), and ICo (P= 0.036). All IV and IM administrations resulted in deep sedation, but 70% of the IV and 10% of the IM sedation events resulted in apnea and required intermittent positive ventilation via endotracheal tube. Fifty percent of the ICo sedation events and 10% of the SC sedation events did not result in sedation. One successful SC sedation event resulted in apnea. In part two, echocardiograms were performed in the same rattlesnakes at baseline and at maximum effect of sedation with 20 mg/kg alfaxalone administered IM. Cardiac contractility and output were unaffected. Administration of alfaxalone at 20 mg/kg IM cranial to the heart should facilitate safe handling and minimally invasive procedures in prairie rattlesnakes and related species.

Pharmacokinetic / Pharmacodynamic (PK/PD) Simulations Guide Selection of the Dose for Administration of Efgartigimod Subcutaneously in a Phase 3 Clinical Trial in Patients with Primary Immune Thrombocytopenia

IntroductionEfgartigimod (ARGX-113) is a human IgG1-derived Fc fragment that binds with high affinity to FcRn in a pH dependent way, resulting in a blockade of FcRn-mediated recycling of IgGs. This leads to rapid degradation of all IgGs, including disease associated autoantibodies.The efficacy, safety, tolerability, and pharmacokinetic (PK) and pharmacodynamic (PD) profile of intravenously (IV) administered efgartigimod have been assessed during a Phase 1 study in healthy subjects (Ulrichts P. JCI. 2018;128), Phase 2 studies in patients with Myasthenia gravis (MG) (Howard JF. Neurol. 2019;92) and Immune Thrombocytopenia (ITP) (Newland AC. Am J Hematol. 2020;95:178-187), and a Phase 3 study in MG (Howard JF. Lancet Neurol. 2021;20). These studies have demonstrated that a dose of 10 mg/kg efgartigimod, administered in four weekly (qw) IV infusions, achieves close to maximal immunoglobulin G (IgG) reduction and a significant reduction of pathogenic autoantibodies in patients with ITP and MG. Furthermore, this dose was well-tolerated in all populations. Based on the results of the Phase 2 study in Primary ITP, a Phase 3 study was designed for IV administration in patients with persistent or chronic primary ITP (ADVANCE NCT04188379).To allow for a convenient SC administration of efgartigimod at a dose that achieves a similar PD effect comparable to IV 10 mg/kg, a co-formulation with rHuPH20 SC was developed (recombinant human hyaluronidase PH20, an enzyme used to increase the dispersion and absorption of co-administered substances when administered subcutaneously). Here we describe the dose selection process for the SC dose to be used in a Phase 3 study of patients with persistent or chronic ITP.MethodsPK and PD data from a Phase 1 study, including 32 healthy adult male subjects receiving 750 mg, 1250 mg, 1750 mg, or 10 mg/kg single SC injections of efgartigimod co-mixed with rHuPH20 (8 subjects/dose group), were used for a PK/PD analysis to predict the efgartigimod PH20 SC dose that would result in a similar PD effect compared to the benchmark dose from previous studies of 10 mg/kg IV (1 hour infusion and body weight of 70 kg).ResultsWeekly SC administration of 1000 mg efgartigimod co-mixed with 2000 U/mL rHuPH20 was predicted to result in comparable maximum total IgG reduction after the 4 th SC injection (days 22-29) as after the 4 th IV infusion of 10 mg/kg administered qw (Figure 1). Additionally, the area under the curve for total IgG concentration after the 4th dose (days 22-29) and trough IgG reduction (measured prior to dose on day 29) were predicted to be comparable between weekly 1000 mg SC and the weekly 10 mg/kg IV benchmark dose.No statistically significant effect of body weight on the PK and PD of efgartigimod PH20 SC was found.DiscussionThese results informed the weekly SC dose administration schedule in ADVANCE SC, a Phase 3, multicenter, randomized, double-blinded, placebo-controlled trial (NCT04687072) for evaluation of efficacy and safety of efgartigimod PH20 SC in adults with persistent or chronic primary ITP. Efgartigimod PH20 SC or placebo PH20 SC will be given weekly on visits 1-4 and then either weekly or every other week from visits 5 to 16, as determined by platelet counts. The frequency of administration will remain unchanged for the last 7 weeks (visits 17 to 24) to evaluate the sustainable platelet count improvement as the primary objective. Secondary objectives include extent of disease control (overall platelet count response, use of rescue treatment, and changes in concurrent ITP therapy), bleeding events, and quality of life assessments. ADVANCE SC recruitment is currently ongoing across approximately 70 sites in Asia-Pacific, Europe, Japan, Latin America, Middle East, Africa, and USA. [Display omitted] DisclosuresGhanima: Amgen: Honoraria, Membership on an entity's Board of Directors or advisory committees; Bristol-Myers Squibb: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Novartis: Honoraria, Membership on an entity's Board of Directors or advisory committees; Principia: Membership on an entity's Board of Directors or advisory committees; Sanofi: Membership on an entity's Board of Directors or advisory committees; Bayer: Honoraria, Research Funding; Pfizer: Research Funding. McDonald: Bayer, Sobi, Novartis, Amgen, argenx: Honoraria; Grifols: Research Funding. Jain: GBT: Speakers Bureau; Novartis: Speakers Bureau; Argenx: Other: advisory board; Sanofi: Other: advisory board; DOVA: Other: advisory board. Oliva: Novartis, Celgene, Bristol-Myers Squibb: Membership on an entity's Board of Directors or advisory committees; Daiichi: Consultancy; Alexion, argenx, Amgen: Consultancy, Membership on an entity's Board of Directors or advisory committees. Hultberg: argenx: Current Employment, Patents & Royalties. Gandini: argenx: Current Employment, Current equity holder in publicly-traded company, Divested equity in a private or publicly-traded company in the past 24 months. Hofman: argenx: Current Employment. Van Bragt: Curare Consulting BV: Other: Partner; argenx: Consultancy. Parys: argenx: Current Employment. van Hoorick: argenx: Current Employment. Miyakawa: Sanofi: Consultancy; Zenyaku Kogyo: Consultancy; Sanofi: Research Funding; argenx: Consultancy, Research Funding. Broome: Alexion, argenx, Apellis, Sanofi: Honoraria.

Clinical Administration Characteristics of Subcutaneous and Intravenous Administration of Daratumumab in Multiple Myeloma Patients at Mayo Clinic

Clinical Administration Characteristics of Subcutaneous and Intravenous Administration of Daratumumab in Multiple Myeloma Patients at Mayo Clinic

Subcutaneous Daratumumab with Rapid Corticosteroid Tapering in Relapsed or Refractory Multiple Myeloma Patients: Part 3 Update of the Open-Label, Multicenter, Phase 1b Pavo Study

Subcutaneous Daratumumab with Rapid Corticosteroid Tapering in Relapsed or Refractory Multiple Myeloma Patients: Part 3 Update of the Open-Label, Multicenter, Phase 1b Pavo Study

Evaluation of glucose absorption rates following intracoelomic or subcutaneous administration in experimentally dehydrated inland bearded dragons (Pogona vitticeps).

To evaluate glucose absorption rates as an indirect measure of fluid absorption after SC or intracoelomic (ICe) administration of 2.5% dextrose solution to experimentally dehydrated inland bearded dragons (Pogona vitticeps). 9 adult bearded dragons. In a randomized, blinded, placebo-controlled, crossover design study, bearded dragons were experimentally dehydrated with a previously described protocol and then received 2.5% dextrose solution (a 1:1 mixture of 5% dextrose in isotonic multiple electrolytes solution; 20 mL/kg), SC or ICe, or a control treatment (the same electrolytes solution without added glucose; 20 mL/kg). Blood glucose (BG) concentrations were measured at predetermined times up to 24 hours after fluid administration. There was a ≥ 14-day washout period between treatments. Mean changes in BG concentration from baseline were compared among treatments. Administration of 2.5% dextrose solution by either route increased BG concentration with a significantly greater change in values within 5 minutes, compared with control treatment results. The mean change in BG concentration after ICe administration was significantly greater than that after SC administration 15 and 30 minutes after injection, with mean differences of -50 and -36 mg/dL, respectively, for the SC treatment. Within 1 hour after fluid administration, there was no significant difference in BG values between the 2 dextrose administration routes. Findings supported that fluid therapy by SC administration, which carries a lower risk of iatrogenic complications, can provide results similar to those achieved with ICe administration.

The pharmacokinetics of letrozole and its effect on gonadotropins in anestrous ewes

The aim of this study was to determine the pharmacokinetics of letrozole and its effect on FSH and LH concentrations after single (IV, IM, SC) and repeated IV doses in anestrous ewes. This study was conducted in experiments 1 and 2 by randomly dividing 24 healthy Akkaraman ewes in anestrus into two equal groups. In experiment 1, the pharmacokinetics of letrozole following single IV, IM, and SC administration at 1 mg/kg dose and its effect of a single IV dose on plasma FSH and LH concentration were determined. In experiment 2, the effect of repeated IV doses of letrozole on FSH and LH concentrations was established. Plasma concentration of letrozole was measured using high-performance liquid chromatography, and pharmacokinetic parameters were calculated by non-compartmental analysis. FSH and LH concentrations were quantified using ELISA. The elimination half-life (t1/2ʎz) for IV, IM, and SC routes were 9.94, 37.29, and 41.07 h, respectively. The IV route for letrozole had a total clearance of 0.11 L/h/kg and a volume of distribution at a steady state of 1.50 L/kg. The peak plasma concentration was 0.11 μg/mL for the IM route and 0.14 μg/mL for the SC routes. The bioavailability was 55.18% for the IM route and 75.34% for the SC route. Letrozole following single and repeated (every 24 h for 3 days) IV administrations at 1 mg/kg dose did not affect LH concentration in anestrous ewes but caused an increase in the FSH concentration. This increase in FSH concentration may create a potential for the use of letrozole in ovarian superstimulation protocols. Favorable pharmacokinetic properties (long t1/2ʎz and good bioavailability) of letrozole for IM and SC routes require further investigation before use in estrus induction or estrus synchronization protocols in sheep.

Oral supplementation of sea cucumber and its hydrolysate mitigates ultraviolet A-induced photoaging in hairless mice.

Chronic exposure to ultraviolet (UV) radiation promotes skin photoaging, which is clinically characterized by dryness, laxity, and wrinkling. Sea cucumber (Stichopus japonicus) (SC) is a marine organism with culinary and medicinal applications, especially in Asian countries. It is also a potential nutraceutical as it exhibits bioactive effects, such as antioxidant, antitumor, and anticancer activity. This study examined the effects of SC and its hydrolysate (SCH) on ultraviolet A (UVA) induced skin barrier function and wrinkle formation using hairless mice. Ultraviolet A significantly induced transepidermal water loss and wrinkle formation, which were significantly mitigated upon oral administration of SC and SCH. Sea cucumber also mitigated the UVA-induced downregulation of epidermal natural moisturizing factors and the upregulation of Aqp3, Mmp13, Tnfa, and Il6 mRNA levels in the mouse skin. Taken together, these results suggest that dietary SC and SCH exert anti-photoaging effects by modulating filaggrin synthesis and desquamation in the epidermis and regulating the NF-κB pathway in the skin. Our research indicates that SC and SCH have potential applications in nutricosmetics for photoaging. © 2021 Society of Chemical Industry.

MK-801-induced behavioral and dopaminergic responses in the shell part of the nucleus accumbens in adult male rats are disrupted after neonatal blockade of the ventral subiculum

The present study was conducted in the context of animal modeling of schizophrenia. It investigated in adult male rats, after transient neonatal blockade of the ventral subiculum (VSub), the impact of a very specific non-competitive antagonist of NMDA receptors (MK-801) on locomotor activity and dopaminergic (DAergic) responses in the dorsomedial shell part of the nucleus accumbens (Nacc), a striatal subregion described as the common target region for antipsychotics.The functional neonatal inactivation of the VSub was achieved by local microinjection of tetrodotoxin (TTX) at postnatal day 8 (PND8). Control pups were microinjected with the solvent phosphate buffered saline (PBS). Locomotor responses and DAergic variations in the dorsomedial shell part of the Nacc were measured simultaneously using in vivo voltammetry in awake, freely moving male animals after sc administration of MK-801. The following results were obtained: 1) a dose-dependent increase in locomotor activity in PBS and TTX animals, greater in TTX rats/PBS rats; and 2) divergent DAergic responses for PBS and TTX animals. A decrease in DA levels with a return to around basal values was observed in PBS animals. An increase in DA levels was obtained in TTX animals. The present data suggest that neonatal blockade of the VSub results in disruption in NMDA glutamatergic transmission, causing a disturbance in DA release in the dorsomedial shell in adults male rats. In the context of animal modeling of schizophrenia using the same approach it would be interesting to investigate possible changes in postsynaptic NMDA receptors-related proteins in the dorsomedial shell region in the Nacc.

Pharmacokinetics of tulathromycin on plasma and semen of beef bulls

The objective of this investigation was to evaluate the pharmacokinetic parameters of tulathromycin in plasma and semen of beef bulls after administering a single sc dose at two different sites in the neck. Four Simmental bulls with excellent temperament received a comprehensive physical exam that included breeding soundness examination. In addition, blood was collected and analyzed for CBC and chemical panel in order to rule out any subclinical liver or kidney disease. All bulls were diagnosed as healthy and satisfactory potential breeders. The mean plasma levels of tulathromycin for the two neck sites of sc administration were not different between posterior aspect of the ear where it attaches to the head (RP; regio parotidea; 77.9 ± 43.3 ng/mL; X ± SD) and to the middle of the neck (RC; regio collis lateralis; 73.7 ± 39.7 ng/mL; P = 0.84). The mean seminal plasma levels of tulathromycin after administration in the RP was 608 ± 374 ng/mL and for RC was 867 ± 599 ng/mL without differences between both sites (P = 0.29). The mean level of tulathromycin in plasma was 75.8 ± 40.2 ng/mL, which was lower than mean seminal plasma levels of 781 ± 482 ng/mL (P = 0.001). The plasma peak tulathromycin concentration (Cmax) was 160 ± 27 ng/mL at 21 ± 6 h (Tmax) post-administration. The seminal plasma Cmax was 1539 ± 44.4 ng/mL at 33.00 ± 18.00 h (Tmax) post-administration. The Cmax between plasma and seminal plasma were different (P = 0.008) without any differences in Tmax between plasma and seminal plasma (P = 0.35). The terminal half-life for plasma tulathromycin (81.4 ± 27.6 h) showed a tendency to be shorter than in seminal plasma (114.7 ± 21.7; P = 0.10). The plasma area under the curve concentration time from the first to the last sample (AUC0–last) was 15,440 ± 1717 ng/mL/h, which was significatively smaller compared with 171,071 ± 58,556 ng/mL/h for seminal plasma AUC0–last (P = 0.01). The plasma means residence time from the first to the last sample (MRT0-last) was 89.3 ± 5.1 h and it was shorter than for seminal plasma of 96.6 ± 5.0 h (P = 0.05). From the present investigation, it was concluded that tulathromycin is a suitable antibiotic based in its pharmacokinetic properties that could be used for treatment of bull genital infections when its application is indicated.

Mice Treated Subcutaneously with Mouse LPS-Converted PrPres or LPS Alone Showed Brain Gene Expression Profiles Characteristic of Prion Disease

Previously, we showed that bacterial lipopolysaccharide (LPS) converts mouse PrPC protein to a beta-rich isoform (moPrPres) resistant to proteinase K. In this study, we aimed to test if the LPS-converted PrPres is infectious and alters the expression of genes related to prion pathology in brains of terminally sick mice. Ninety female FVB/N mice at 5 weeks of age were randomly assigned to 6 groups treated subcutaneously (sc) for 6 weeks either with: (1) Saline (CTR); (2) LPS from Escherichia coli 0111:B4 (LPS), (3) one-time sc administration of de novo generated mouse recombinant prion protein (moPrP; 29-232) rich in beta-sheet by incubation with LPS (moPrPres), (4) LPS plus one-time sc injection of moPrPres, (5) one-time sc injection of brain homogenate from Rocky Mountain Lab (RLM) scrapie strain, and (6) LPS plus one-time sc injection of RML. Results showed that all treatments altered the expression of various genes related to prion disease and neuroinflammation starting at 11 weeks post-infection and more profoundly at the terminal stage. In conclusion, sc administration of de novo generated moPrPres, LPS, and a combination of moPrPres with LPS were able to alter the expression of multiple genes typical of prion pathology and inflammation.

Evaluation of subcutaneous versus intravenous administration of apomorphine for induction of emesis in dogs.

To prospectively compare the effectiveness and any adverse effects of apomorphine administered SC or IV for induction of emesis in dogs. 42 client-owned dogs. Dogs for which emesis induction was deemed appropriate by the attending clinician were prospectively randomized to receive apomorphine (0.03 mg/kg [0.01 mg/lb]) either SC (n = 20) or IV (22). Data collected included whether emesis was successfully induced, time from drug administration to emesis, number of emetic events, and adverse events (eg, sedation, protracted vomiting, or other). Of the 20 dogs given apomorphine SC, 16 (80%) vomited. Of the 22 dogs given apomorphine IV, 18 (82%) vomited. With regard to route of administration, the number of dogs in which emesis was induced did not differ significantly. Median time to the first emetic event was 13.5 minutes (range, 3 to 32 minutes) in the SC treatment group and 2 minutes (range, 1 to 5 minutes) in the IV treatment group; the difference was significant. There was no significant difference in the number of emetic events or frequency of adverse events between the 2 groups. Apomorphine administered SC or IV reliably induced emesis in dogs. Compared with SC administration of apomorphine, the time from drug administration to emesis associated with IV administration was significantly shorter, a finding that has clinical importance.

IL-10-Dependent Amelioration of Chronic Inflammatory Disease by Microdose Subcutaneous Delivery of a Prototypic Immunoregulatory Small Molecule

One of the interventional strategies to reestablish the immune effector/regulatory balance, that is typically altered in chronic inflammatory diseases (CID), is the reinforcement of endogenous immunomodulatory pathways as the one triggered by interleukin (IL)-10. In a recent work, we demonstrated that the subcutaneous (sc) administration of an IL-10/Treg-inducing small molecule-based formulation, using a repetitive microdose (REMID) treatment strategy to preferentially direct the effects to the regional immune system, delays the progression of atherosclerosis. Here we investigated whether the same approach using other IL-10-inducing small molecule, such as the safe, inexpensive, and widely available polyphenol curcumin, could induce a similar protective effect in two different CID models. We found that, in apolipoprotein E deficient mice, sc treatment with curcumin following the REMID strategy induced atheroprotection that was not consequence of its direct systemic lipid-modifying or antioxidant activity, but instead paralleled immunomodulatory effects, such as reduced proatherogenic IFNγ/TNFα-producing cells and increased atheroprotective FOXP3+ Tregs and IL-10-producing dendritic and B cells. Remarkably, when a similar strategy was used in the neuroinflammatory model of experimental autoimmune encephalomyelitis (EAE), significant clinical and histopathological protective effects were evidenced, and these were related to an improved effector/regulatory cytokine balance in restimulated splenocytes. The essential role of curcumin-induced IL-10 for neuroprotection was confirmed by the complete abrogation of the clinical effects in IL-10-deficient mice. Finally, the translational therapeutic prospection of this strategy was evidenced by the neuroprotection observed in mice starting the treatment one week after disease triggering. Collectively, results demonstrate the power of a simple natural IL-10-inducing small molecule to tackle chronic inflammation, when its classical systemic and direct pharmacological view is shifted towards the targeting of regional immune cells, in order to rationally harness its immunopharmacological potential. This shift implies that many well-known IL-10-inducing small molecules could be easily reformulated and repurposed to develop safe, innovative, and accessible immune-based interventions for CID.

Novel probiotic yeast from Miso promotes regulatory dendritic cell IL-10 production and attenuates DSS-induced colitis in mice.

Yeasts are a type of fungi thought to have probiotic functions. In this study, we isolated a novel probiotic yeast (Zygosaccharomyces sapae strain I-6) from Miso (a traditional Japanese fermented food). We examined its effects on phenotypic changes in intestinal dendritic cells (DCs), and evaluated its anti-inflammatory effects in dextran sulfate sodium (DSS)-induced colitis. A single colony was selected from homogenized Miso, based on its ability to produce interleukin (IL)-10 in CD11c+ bone marrow DCs (BMDCs) in vitro. The anti-inflammatory effects of strain I-6 on CD11c+ BMDCs and CD11c+ CD103+ DCs were analyzed in mouse mesenteric lymph nodes in vitro and in a DSS mouse model. The IL-10 concentrations in the co-culture BMDC supernatants treated with I-6 were dramatically higher than in those treated with Saccharomyces cerevisiae (Sc). IL-10 production is mediated by both TLR2 and Dectin-1. β-Glucan extracted from I-6 also induced higher levels of IL-10 production in BMDCs than β-glucan from Sc. The number of mesenteric lymph node CD11c+ CD103+ DCs was significantly increased by I-6 administration, compared with Sc administration. Strain I-6 showed strong anti-inflammatory effects on DSS-induced colitis compared to Sc. Moreover, the adoptive transfer of I-6-treated BMDCs showed anti-inflammatory effects on DSS-induced colitis in mice without oral administration of I-6 cells. Strain I-6 induced phenotypic changes in intestinal CD11c+ DCs characterized by high IL-10 production and exerted strong anti-inflammatory effects on DSS-induced colitis. Traditional Japanese fermented foods may be a valuable source of probiotic yeasts for effective IBD therapy and treatment.

Weekly Dosing of Bortezomib in RVD Achieves Minimal Toxicity with No Reduction in Efficacy in a Diverse Cohort of Multiple Myeloma Patients

Introduction: Lenalidomide, bortezomib, and dexamethasone is a standard of care in the treatment of fit multiple myeloma patients due to high efficacy, with ORR exceeding 90% in the first-line setting (Richardson et al. 2010). The initial RVD regimen utilized a 21-day cycle with bortezomib administered IV 1.3 mg/m2 days 1, 4, 8, and 11; lenalidomide 25 mg administered days 1-14; and dexamethasone administered 160 to 320 mg per cycle. However, toxicity may be treatment-limiting, with bortezomib-induced neuropathy affecting up to 80% of patients. Modifications to RVD to optimize tolerance include reducing the bortezomib dose to a weekly schedule (1.6 mg/m2 IV or 1.3 mg/m2SC) and extending the cycle to 28 or 35 days (Broijl et al. 2016; O'Donnell et al. 2014). Notably, those regimens were studied in transplant-ineligible or relapsed/refractory patients. Based on regimens like CyBorD (which utilize weekly SC administration of bortezomib, are well-tolerated and are efficacious), we modified the standard 21-day RVD regimen to include 3 doses of weekly bortezomib in an attempt to preserve efficacy while minimizing toxicity. We present a retrospective analysis of both fit and transplant-ineligible patients treated at our institution using “Louisville RVD.”Methods: We identified the charts of patients who received RVD over a 21-day cycle at the following starting doses: lenalidomide 25 mg orally days 1-14; bortezomib 1.5 mg/m2 SC days 1, 8, and 15; and dexamethasone 40 mg days 1, 8, and 15. Autologous stem cell harvest took place after 4 cycles of lenalidomide-based therapy when feasible, in appropriate candidates. We noted demographic factors, ISS stage, performance status, cytogenetic risk stratification, line of therapy (initial, later-line, and consolidation), history of autologous transplant, degree of response (PD, SD, PR, VGPR, and CR based on International Myeloma Working Group criteria), EFS, OS, and toxicities.Results: We identified 23 patients who received Louisville RVD between 2009 and 2017. Median age was 59 years (range 37-77) at treatment start; 9 (39%) were 65 or older; 12 (52%) were male; 11 (48%) were African-American; ISS stages were I in 6 (26%), II in 7 (30%), III in 9 (39%), and missing in 1 patient; ECOG status was 0 in 7 (30%), 1 in 11 (48%), and 2 in 5 (21%). Line of therapy was 1 in 13 (56%) and 2 or later in 10 (44%); RVD was used as post-transplant consolidation in 4 (14%). Line of therapy ranged from 1 to 8. 16 patients (57%) were treated with intent to transplant. The median number of cycles given was 4 (range 1-64). Dose reductions and discontinuation occurred in 5 (22%) patients and 1 (4%) patient after 1 cycle, respectively. Response was assessable in 22 patients. 21 (95%) of patients achieved PR or better; 3 patients (14%) achieved CR, 7 (32%) VGPR; and 11 (50%) PR. OS and EFS at 1 year were 90% and 60%, respectively; median duration of follow-up was 15.5 months (range 1.2-95.1); follow-up time was limited for a significant fraction of our patients. There was no association of relapse with ISS stage (p=0.357), ECOG score (p=0.088), or cytogenetic risk (p=1.00). Treatment-related toxicities were reported for 11 patients. Treatment-emergent neuropathy was seen in 5 patients (22%); 4 patients experienced grade 1 neuropathy (17%), and 1 patient experienced grade 3 neuropathy (4%). 1 patient underwent dose-reduction of bortezomib to 1.3 mg/m2 after 18 cycles. 6 patients had treatment related cytopenias (26%), of which 1 (4%) was grade 3.Conclusions: Retrospective analysis of 21-day “Louisville RVD” with weekly subcutaneous bortezomib demonstrates efficacy comparable to previously published RVD regimens. Toxicity, especially peripheral neuropathy, favors the weekly SC administration schedule. Dose reductions were uncommon and treatment discontinuations were rare. Patients may ultimately achieve superior bortezomib dosing due to rarity of dose reductions. Our cohort was well-balanced with regard to ethnicity, gender, age, and performance status. Treatment was efficacious and well-tolerated in both transplant and non-transplant candidates. [Display omitted] DisclosuresNo relevant conflicts of interest to declare.

Safety and Tolerability of the Combination of Interleukin-2 (rIL-2) and Rituximab in Patients with Refractory/Relapsed Follicular Non Hodgkin Lymphoma. Preliminary Data from the Pearl Study.

Background: Rituximab (R) is a chimeric IgG1 mAb antibody directed against the CD20 antigen, expressed on greater than 90% of all B-cell lymphomas. Despite the encouraging results, responses to R monotherapy are usually partial and of limited duration. Therefore, new strategies to increase the clinical effectiveness of R are being explored. Antibody-dependent cellular cytotoxicity (ADCC) is an important mechanism of Rituximab's activity. Studies (Dunne et al. J Immunol 2001; 167:3129–3138) have provided evidence that rIL-2 can augment ADCC and thereby enhance the efficacy of antitumor antibodies such as R.Methods: A multicenter Phase II trial was conducted to evaluate the efficacy of rIL-2+R compared to R alone. Subjects were R naïve with follicular lymphoma who were relapsed or unresponsive to previous chemotherapy. Subjects were randomized 1:1 to either IV R (375 mg/m2) monotherapy (n=29) once weekly (weeks 1–4) or the same dose and schedule of R in combination with SC rIL-2 (n=27) three times weekly at 14 MIU (weeks 2–5) followed by 10 MIU (weeks 6–9). The primary and secondary objectives were to compare overall response rate (ORR) and time to progression (TTP) for subjects receiving rIL-2+R with those receiving R monotherapy. A further objective was to evaluate the safety of an 8-week SC administration of rIL-2 with 4 week IV administration of R. From October 2004 until May 2005, 69 participating centres enrolled 56 patients.Results: Twenty-seven subjects in the combination arm received a mean cumulative dosage of 82.8 MIU (range: 0–96) of rIL-2. The most common adverse events (AEs) observed in this arm were fever, chills and injection site reactions. Safety was comparable in the combination and monotherapy arms for grade 1 (33 vs. 38%) and grade 3 (11 vs. 13%) AEs. Treatment related grade 2 AEs were more common in the combination arm (44% vs 0%) with most related to skin and subcutaneous tissue reactions. No grade 4 AEs were reported. Five patients were withdrawn from the study, three in the combination arm and two in R alone group for disease progression (2 subjects in the combination arm and 1 in the R monotherapy), adverse event (1 in the combination arm related to a R reaction) and withdrawal of consent (1).Conclusions: This preliminary data confirm that the addition of rIL-2 to R therapy appears to be safe and well tolerated. The majority of the subjects were able to receive the total dose of rIL-2. The observed adverse events were manageable and related to skin reactions and flu-like symptoms, as expected with rIL-2. The main reason for study treatment discontinuation was disease progression. Trial assessment is ongoing.