Clinical evaluation of PF614, a novel TAAP prodrug of oxycodone, versus OxyContin in a multi-ascending dose study with a bioequivalence arm in healthy volunteers.

PF614, a trypsin-activated abuse protection oxycodone prodrug designed to reduce recreational drug abuse, was compared to OxyContin for safety and pharmacokinetics (PKs) of plasma oxycodone following oral administration. This study was a two-part design including a multi-ascending dose (part A) and a bioequivalence (BE) study (part B) in healthy volunteers. In part A, 24 subjects were randomized 3:1 to receive PF614 (50, 100, or 200 mg, n = 6/cohort) or OxyContin (20, 40, or 80 mg; n = 2/cohort) in ascending cohorts, delivered every 12 h for a total of nine doses. In part B, 60 subjects randomized in a four-way crossover to evaluate BE, received PF614 100 mg and OxyContin 40 mg in fasted and fed (high-fat diet) states. All subjects were naltrexone blocked prior to first study drug administration to protect against opioid-related adverse effects; repeat doses were provided on days 1-5. In part A, PF614 was well-tolerated following twice daily doses of up to 200 mg for 5 days. Plasma oxycodone maximal plasma concentration and area under the concentration time curve increased linearly with increasing doses. Part B showed that plasma oxycodone BE was achieved following 100 mg PF614 or 40 mg OxyContin under both fasted and fed conditions. Additionally, PF614 provided similar oxycodone exposures following both fasted and fed states. This study confirms findings from our single-ascending dose study, showing that PF614 100 mg releases oxycodone with a PK profile comparable to 40 mg OxyContin under both fasted and fed conditions and with a similar safety profile under naltrexone-blocked conditions.

A lung targeted miR-29 mimic as a therapy for pulmonary fibrosis.

BACKGROUND: MicroRNAs are non-coding RNAs that negatively regulate gene networks. Previously, we reported that systemically delivered miR-29 mimic MRG-201 reduced fibrosis in animal models, supporting the consideration of miR-29-based therapies for idiopathic pulmonary fibrosis (IPF). METHODS: We generated MRG-229, a next-generation miR-29 mimic based on MRG-201 with improved chemical stability due to additional sugar modifications and conjugation with the internalization moiety BiPPB (PDGFbetaR-specific bicyclic peptide)1. We investigated the anti-fibrotic efficacy of MRG-229 on TGF-ß1 treated human lung fibroblasts (NHLFs), human precision cut lung slices (hPCLS), and in vivo bleomycin studies; toxicology was assessed in two animal models, rats, and non-human primates. Finally, we examined miR-29b levels in a cohort of 46 and 213 patients with IPF diagnosis recruited from Yale and Nottingham Universities (Profile Cohort), respectively. FINDINGS: The peptide-conjugated MRG-229 mimic decreased expression of pro-fibrotic genes and reduced collagen production in each model. In bleomycin-treated mice, the peptide-conjugated MRG-229 mimic downregulated profibrotic gene programs at doses more than ten-fold lower than the original compound. In rats and non-human primates, the peptide-conjugated MRG-229 mimic was well tolerated at clinically relevant doses with no adverse findings observed. In human peripheral blood from IPF patients decreased miR-29 concentrations were associated with increased mortality in two cohorts potentially identified as a target population for treatment. INTERPRETATION: Collectively, our results provide support for the development of the peptide-conjugated MRG-229 mimic as a potential therapy in humans with IPF. FUNDING: This work was supported by NIH NHLBI grants UH3HL123886, R01HL127349, R01HL141852, U01HL145567.

Cobomarsen, an Oligonucleotide Inhibitor of miR-155, Slows DLBCL Tumor Cell Growth In Vitro and In Vivo.

PURPOSE: miRNA-155 is an oncogenic miRNA highly expressed in B-cell malignancies, particularly in the non-germinal center B-cell or activated B-cell subtype of diffuse large B-cell lymphoma (ABC-DLBCL), where it is considered a potential diagnostic and prognostic biomarker. Thus, miR-155 inhibition represents an important therapeutic strategy for B-cell lymphomas. In this study, we tested the efficacy and pharmacodynamic activity of an oligonucleotide inhibitor of miR-155, cobomarsen, in ABC-DLBCL cell lines and in corresponding xenograft mouse models. In addition, we assessed the therapeutic efficacy and safety of cobomarsen in a patient diagnosed with aggressive ABC-DLBCL. EXPERIMENTAL DESIGN: Preclinical studies included the delivery of cobomarsen to highly miR-155-expressing ABC-DLBCL cell lines to assess any phenotypic changes, as well as intravenous injections of cobomarsen in NSG mice carrying ABC-DLBCL xenografts, to study tumor growth and pharmacodynamics of the compound over time. To begin to test its safety and therapeutic efficacy, a patient was recruited who underwent five cycles of cobomarsen treatment. RESULTS: Cobomarsen decreased cell proliferation and induced apoptosis in ABC-DLBCL cell lines. Intravenous administration of cobomarsen in a xenograft NSG mouse model of ABC-DLBCL reduced tumor volume, triggered apoptosis, and derepressed direct miR-155 target genes. Finally, the compound reduced and stabilized tumor growth without any toxic effects for the patient. CONCLUSIONS: Our findings support the potential therapeutic application of cobomarsen in ABC-DLBCL and other types of lymphoma with elevated miR-155 expression.

Efficiency and Target Derepression of Anti-miR-92a: Results of a First in Human Study.

MicroRNA (miRNA) inhibition is a promising therapeutic strategy in several disease indications. MRG-110 is a locked nucleic acid-based antisense oligonucleotide that targets miR-92a-3p and experimentally was shown to have documented therapeutic effects on cardiovascular disease and wound healing. To gain first insights into the activity of anti-miR-92a in humans, we investigated miR-92a-3p expression in several blood compartments and assessed the effect of MRG-110 on target derepression. Healthy adults were randomly assigned (5:2) to receive a single intravenous dose of MRG-110 or placebo in one of seven sequential ascending intravenous dose cohorts ranging from 0.01 to 1.5 mg/kg body weight. MiR-92a-3p whole blood levels were time and dose dependently decreased with half-maximal inhibition of 0.27 and 0.31 mg/kg at 24 and 72 h after dosing, respectively. In the high-dose groups, >95% inhibition was detected at 24-72 h postinfusion and significant inhibition was observed for 2 weeks. Similar inhibitory effects were detected in isolated CD31+ cells, and miR-92a-3p expression was also inhibited in extracellular vesicles in the high-dose group. Target derepression was measured in whole blood and showed that ITGA5 and CD93 were increased at a dose of 1.5 mg/kg. Single-cell RNA sequencing of peripheral blood cells revealed a cell type-specific derepression of miR-92a targets. Together this study demonstrates that systemic infusion of anti-miR-92a efficiently inhibits miR-92a in the peripheral blood compartment and derepresses miR-92a targets in humans.

A MicroRNA-29 Mimic (Remlarsen) Represses Extracellular Matrix Expression and Fibroplasia in the Skin.

MicroRNA-29 (miR-29) negatively regulates fibrosis and is downregulated in multiple fibrotic organs and tissues, including in the skin. miR-29 mimics prevent pulmonary fibrosis in mouse models but have not previously been tested in the skin. This study aimed to identify pharmacodynamic biomarkers of miR-29 in mouse skin, to translate those biomarkers across multiple species, and to assess the pharmacodynamic activity of a miR-29b mimic (remlarsen) in a clinical trial. miR-29 biomarkers were selected based on gene function and mRNA expression using quantitative reverse transcriptase polymerase chain reaction. Those biomarkers comprised multiple collagens and other miR-29 direct and indirect targets and were conserved across species; remlarsen regulated their expression in mouse, rat, and rabbit skin wounds and in human skin fibroblasts in culture, while a miR-29 inhibitor reciprocally regulated their expression. Biomarker expression translated to clinical proof-of-mechanism; in a double-blinded, placebo-randomized, within-subject controlled clinical trial of single and multiple ascending doses of remlarsen in normal healthy volunteers, remlarsen repressed collagen expression and the development of fibroplasia in incisional skin wounds. These results suggest that remlarsen may be an effective therapeutic to prevent formation of a fibrotic scar (hypertrophic scar or keloid) or to prevent cutaneous fibrosis, such as scleroderma.

A synthetic microRNA-92a inhibitor (MRG-110) accelerates angiogenesis and wound healing in diabetic and nondiabetic wounds.

There is a strong unmet need for new therapeutics to accelerate wound healing across both chronic and acute indications. It is well established that local tissue hypoxia, vascular insufficiency, and/or insufficient angiogenesis contribute to inadequate wound repair in the context of diabetic foot ulcers as well as to other chronic wounds such as venous stasis and pressure ulcers. microRNA-92a-3p (miR-92a) is a potent antiangiogenic miRNA whose inhibition has led to increases in angiogenesis in multiple organ systems, resulting in an improvement in function following myocardial infarction, limb ischemia, vascular injury, and bone fracture. Due to their pro-angiogenic effects, miR-92a inhibitors offer potential therapeutics to accelerate the healing process in cutaneous wounds as well. This study investigated the effect of a development stage locked nucleic acid-modified miR-92a inhibitor, MRG-110, in excisional wounds in db/db mice and in normal pigs. In both acute and chronic wounds, MRG-110 increased granulation tissue formation as assessed by histology, angiogenesis as assessed by immunohistochemistry and tissue perfusion, and wound healing as measured by time to closure and percent closure over time. The effects of MRG-110 were greater than those that were observed with the positive controls rhVEGF-165 and rhPDGF-BB, and MRG-110 was at least additive with rhPDGF-BB when co-administered in db/db mouse wounds. MRG-110 was found to up-regulate expression of the pro-angiogenic miR-92a target gene integrin alpha 5 in vitro in both human vascular endothelial cells and primary human skin fibroblasts and in vivo in mouse skin, demonstrating its on-target effects in vitro and in vivo. Additional safety endpoints were assessed in both the mouse and pig studies with no safety concerns noted. These studies suggest that MRG-110 has the potential to accelerate both chronic and acute wound healing and these data provide support for future clinical trials of MRG-110.

A phase I trial of PX-12, a small-molecule inhibitor of thioredoxin-1, administered as a 72-hour infusion every 21 days in patients with advanced cancers refractory to standard therapy.

PURPOSE: This phase I trial assessed the safety, dose limiting toxicity (DLT) and pharmacodynamics of PX-12 in adult patients with advanced refractory cancers. METHODS: PX-12 was administered to sequential cohorts as a 72-h infusion utilizing a portable infusion pump on days 1, 2, and 3 of a 21-day cycle at a starting dose level of 300 mg/m(2)/day and escalating dose levels till DLT was observed. Plasma thioredoxin (Trx-1), vascular endothelial growth factor (VEGF) and FGF-2 (fibroblast growth factor) levels were measured predose and during infusion of PX-12. RESULTS: Patients (n = 14) were enrolled to the following dose cohorts, 300 mg/m(2) (n = 3), 400 mg/m(2) (n = 10) and 500 mg/m(2) (n = 1). Common grade 1/2 toxicities included fatigue, taste alteration and odor caused by expired drug metabolite. DLTs were one episode each of grade 3 hypoxia at the 400 mg/m(2) and grade 3 reversible pneumonitis at the 500 mg/m(2) dose levels. Best response was stable disease in a patient with rectal cancer. Predose Trx-1 levels (n = 12) ranged from 5.1 to 30.0 ng/mL (median 12.6 ng/mL). CONCLUSION: PX-12 administered at 400 mg/m(2)/day by 72-hour infusion appears safe and tolerable. Inhibition of thioredoxin is a strategy worth evaluation with next generation of inhibitors.

A randomized phase II study of PX-12, an inhibitor of thioredoxin in patients with advanced cancer of the pancreas following progression after a gemcitabine-containing combination.

PURPOSE: This study evaluated PX-12, a novel small molecule inhibitor of the proto-oncogene (Trx-1), in patients with previously treated advanced pancreatic cancer (APC). METHODS: PX-12 (54 or 128 mg/m²) was administered by 3-hour IV infusion daily × 5 days every 21 days (n = 17). Patients were randomized to either 54 or 128 mg/m² and then stratified based on CA 19-9 level (≥ 1,000 vs. < 1,000 U/ml) and SUV values on PET scans (≥ 7.0 vs. <7.0). The primary endpoint was based on a progression-free survival (PFS) at 4 months in ≥ 40% of patients, and required 40 patients in each arm. An amendment required elevated Trx-1 levels (> 18 ng/ml) as an entry criteria after the first 17 patients were accrued. RESULTS: Plasma Trx-1 levels were elevated in 3/28 (11%) patients screened for study. The grade of the expired metabolite odor was higher in the 128 mg/m² arm. Therapy was well tolerated, and Grade ≥ 3 adverse events were uncommon. The best response was stable disease in 2 patients. There was no consistent decrease in SUV, Trx-1 levels or CA 19-9 levels with therapy. No patients had a PFS of >4 months. Median PFS and survival were 0.9 months (95% CI 0.5-1.2) and 3.2 months (95% CI 2.4-4.2), respectively. CONCLUSIONS: Due to the lack of significant antitumor activity and unexpectedly low baseline Trx-1 levels, the study was terminated early. PX-12 does not appear to be active in unselected patients with previously treated APC.

Interferon-gamma Added During Bacillus Calmette-Guerin Induced Dendritic Cell Maturation Stimulates Potent Th1 Immune Responses.

Dendritic cells (DC) are increasingly prepared in vitro for use in immunotherapy trials. Mature DC express high levels of surface molecules needed for T cell activation and are superior at antigen-presentation than immature DC. Bacillus Calmette-Guerin (BCG) is one of several products known to induce DC maturation, and interferon (IFN)-gamma has been shown to enhance the activity of DC stimulated with certain maturation factors. In this study, we investigated the use of IFN-gamma in combination with the powerful maturation agent, BCG. The treatment of immature DC with IFN-gamma plus BCG led to the upregulation of CD54, CD80, and CD86 in comparison with BCG treatment alone. In MLR or recall immune responses, the addition of IFN-gamma at the time of BCG-treatment did not increase the number of antigen-specific T cells but enhanced the development of IFN-gamma-producing Th1 cells. In primary immune responses, on the other hand, BCG and IFN-gamma co-treated DC stimulated higher proportions of specific T cells as well as IFN-gamma secretion by these T cells. Thus the use of IFN-gamma during BCG-induced DC maturation differentially affects the nature of recall versus naïve antigen-specific T-cell responses. IFN-gamma co-treatment with BCG was found to induce IL-12 and, in some instances, inhibit IL-10 secretion by DC. These findings greatly enhance the potential of BCG-matured dendritic cells for use in cancer immunotherapy.