Ameliorating Active Ulcerative Colitis via an Orally Available Toll-Like Receptor-9 Modifier: A Prospective Open-Label, Multicenter Phase II Trial.

BACKGROUND: Treatment of active ulcerative colitis is associated with incomplete efficacy, adverse events, and loss of response. Toll-like receptor-9 mediates innate and adaptive immune response toward intestinal microorganisms. The oral synthetic oligonucleotide toll-like receptor-9 modulator has demonstrated anti-inflammatory properties in colitis murine models and a satisfactory safety profile in humans. AIM: To evaluate the efficacy and safety of BL-7040 (a Toll-like receptor-9 modulator) in patients with moderately active ulcerative colitis. METHODS: Moderately active ulcerative colitis patients were included in this multicenter, open-label phase IIa trial. Concomitant mesalamine and steroids at a stable dose were allowed. Clinical outcome was evaluated using the Mayo score, histology, and mucosal cytokine levels. Side effects were registered. RESULTS: Sixteen out of 22 patients completed a 5-week treatment course and 2-week follow-up. Six patients discontinued the study, three of them due to adverse events. Clinical remission was observed in two patients (12.5 %), and clinical response as well as mucosal healing were achieved in half (50 %) of the patients, while all others remained stable. Furthermore, mucosal neutrophil (p = 0.002) and mucosal interleukin-6 levels (p = 0.046) were significantly reduced in responders compared to non-responders. Toll-like receptor-9 was well tolerated with only one unrelated to study drug serious adverse event (hemoglobin decrease) and 29 mild-to-moderate adverse events. CONCLUSIONS: Oral administration of the Toll-like receptor-9 agonist BL-7040 appeared efficacious, safe and well tolerated in patients with moderately active ulcerative colitis.

Pharmacokinetic and efficacy study of cisplatin and paclitaxel formulated in a new injectable poly(sebacic-co-ricinoleic acid) polymer.

Injectable biodegradable polymer poly(sebacic-co-ricinoleic acid), P(SA-RA) is currently under development for intratumoral (IT) delivery of drugs for treating solid tumors. This study presents formulation development, pharmacokinetic and efficacy studies of two anticancer drugs (cisplatin and paclitaxel) formulated with P(SA-RA) polymer. In pharmacokinetic study, systemic exposure and pharmacokinetic parameters of cisplatin/paclitaxel following single intravenous (IV) or subcutaneous (SC) doses of cisplatin/paclitaxel was compared with intramuscular (IM) or SC doses of cisplatin/paclitaxel formulated with P(SA-RA) polymer in male CD rat. Simultaneously, the tumor reduction effect and toxicity for these formulations were evaluated in human FaDu head and neck tumor xenograft subcutaneous nude mouse model. Pharmacokinetic data reflect the lower maximal concentrations and sustained release of polymer-cisplatin/paclitaxel formulations compared to standard cisplatin/paclitaxel administration. Regarding efficacy study, a single IT or near the tumor injection (NT) of polymer-paclitaxel or polymer-cisplatin formulation significantly reduced the tumor size, compared to the standard paclitaxel or cisplatin treatments. No death or toxicity and no effect on body weight as well as macroscopic and/or microscopic changes in or near the injected area were observed, proving biocompatibility and acceptability of polymer-formulations. In conclusion, the developed formulation demonstrated controlled release and significant efficacy in delivering these agents and exhibit potential for further clinical development.

Engineering of targeted nanoparticles for cancer therapy using internalizing aptamers isolated by cell-uptake selection.

One of the major challenges in the development of targeted nanoparticles (NPs) for cancer therapy is to discover targeting ligands that allow for differential binding and uptake by the target cancer cells. Using prostate cancer (PCa) as a model disease, we developed a cell-uptake selection strategy to isolate PCa-specific internalizing 2'-O-methyl RNA aptamers (Apts) for NP incorporation. Twelve cycles of selection and counter-selection were done to obtain a panel of internalizing Apts, which can distinguish PCa cells from nonprostate and normal prostate cells. After Apt characterization, size minimization, and conjugation of the Apts with fluorescently labeled polymeric NPs, the NP-Apt conjugates exhibit PCa specificity and enhancement in cellular uptake when compared to nontargeted NPs lacking the internalizing Apts. Furthermore, when docetaxel, a chemotherapeutic agent used for the treatment of PCa, was encapsulated within the NP-Apt, a significant improvement in cytotoxicity was achieved in targeted PCa cells. Rather than isolating high-affinity Apts as reported in previous selection processes, our selection strategy was designed to enrich cancer cell-specific internalizing Apts. A similar cell-uptake selection strategy may be used to develop specific internalizing ligands for a myriad of other diseases and can potentially facilitate delivering various molecules, including drugs and siRNAs, into target cells.

In vivo administration of BL-3050: highly stable engineered PON1-HDL complexes.

BACKGROUND: Serum paraoxonase (PON1) is a high density lipoprotein (HDL)-associated enzyme involved in organophosphate (OP) degradation and prevention of atherosclerosis. PON1 comprises a potential candidate for in vivo therapeutics, as an anti-atherogenic agent, and for detoxification of pesticides and nerve agents. Because human PON1 exhibits limited stability, engineered, recombinant PON1 (rePON1) variants that were designed for higher reactivity, solubility, stability, and bacterial expression, are candidates for treatment. This work addresses the feasibility of in vivo administration of rePON1, and its HDL complex, as a potentially therapeutic agent dubbed BL-3050. METHODS: For stability studies we applied different challenges related to the in vivo disfunctionalization of HDL and PON1 and tested for inactivation of PON1's activity. We applied acute, repetitive administrations of BL-3050 in mice to assess its toxicity and adverse immune responses. The in vivo efficacy of recombinant PON1 and BL-3050 were tested with an animal model of chlorpyrifos-oxon poisoning. RESULTS: Inactivation studies show significantly improved in vitro lifespan of the engineered rePON1 relative to human PON1. Significant sequence changes relative to human PON1 might hamper the in vivo applicability of BL-3050 due to adverse immune responses. However, we observed no toxic effects in mice subjected to repetitive administration of BL-3050, suggesting that BL-3050 could be safely used. To further evaluate the activity of BL-3050 in vivo, we applied an animal model that mimics human organophosphate poisoning. In these studies, a significant advantages of rePON1 and BL-3050 (>87.5% survival versus <37.5% in the control groups) was observed. Furthermore, BL-3050 and rePON1 were superior to the conventional treatment of atropine-2-PAM as a prophylactic treatment for OP poisoning. CONCLUSION: In vitro and in vivo data described here demonstrate the potential advantages of rePON1 and BL-3050 for treatment of OP toxicity and chronic cardiovascular diseases like atherosclerosis. The in vivo data also suggest that rePON1 and BL-3050 are stable and safe, and could be used for acute, and possibly repeated treatments, with no adverse effects.

Quantum dot-aptamer conjugates for synchronous cancer imaging, therapy, and sensing of drug delivery based on bi-fluorescence resonance energy transfer.

We report a novel quantum dot (QD)-aptamer(Apt)-doxorubicin (Dox) conjugate [QD-Apt(Dox)] as a targeted cancer imaging, therapy, and sensing system. By functionalizing the surface of fluorescent QD with the A10 RNA aptamer, which recognizes the extracellular domain of the prostate specific membrane antigen (PSMA), we developed a targeted QD imaging system (QD-Apt) that is capable of differential uptake and imaging of prostate cancer cells that express the PSMA protein. The intercalation of Dox, a widely used antineoplastic anthracycline drug with fluorescent properties, in the double-stranded stem of the A10 aptamer results in a targeted QD-Apt(Dox) conjugate with reversible self-quenching properties based on a Bi-FRET mechanism. A donor-acceptor model fluorescence resonance energy transfer (FRET) between QD and Dox and a donor-quencher model FRET between Dox and aptamer result when Dox intercalated within the A10 aptamer. This simple multifunctional nanoparticle system can deliver Dox to the targeted prostate cancer cells and sense the delivery of Dox by activating the fluorescence of QD, which concurrently images the cancer cells. We demonstrate the specificity and sensitivity of this nanoparticle conjugate as a cancer imaging, therapy and sensing system in vitro.

Formulation of functionalized PLGA-PEG nanoparticles for in vivo targeted drug delivery.

Nanoparticle (NP) size has been shown to significantly affect the biodistribution of targeted and non-targeted NPs in an organ specific manner. Herein we have developed NPs from carboxy-terminated poly(d,L-lactide-co-glycolide)-block-poly(ethylene glycol) (PLGA-b-PEG-COOH) polymer and studied the effects of altering the following formulation parameters on the size of NPs: (1) polymer concentration, (2) drug loading, (3) water miscibility of solvent, and (4) the ratio of water to solvent. We found that NP mean volumetric size correlates linearly with polymer concentration for NPs between 70 and 250 nm in diameter (linear coefficient=0.99 for NPs formulated with solvents studied). NPs with desirable size, drug loading, and polydispersity were conjugated to the A10 RNA aptamer (Apt) that binds to the prostate specific membrane antigen (PSMA), and NP and NP-Apt biodistribution was evaluated in a LNCaP (PSMA+) xenograft mouse model of prostate cancer. The surface functionalization of NPs with the A10 PSMA Apt significantly enhanced delivery of NPs to tumors vs. equivalent NPs lacking the A10 PSMA Apt (a 3.77-fold increase at 24h; NP-Apt 0.83%+/-0.21% vs. NP 0.22%+/-0.07% of injected dose per gram of tissue; mean+/-SD, n=4, p=0.002). The ability to control NP size together with targeted delivery may result in favorable biodistribution and development of clinically relevant targeted therapies.

Clinical manifestations in Israeli cystinuria patients and molecular assessment of carrier rates in Libyan Jewish controls.

BACKGROUND: Cystinuria is an autosomal recessive disease that is manifested by the development of kidney stones. Mutations in SLC3A1 cause type I disease, while mutations in SLC7A9 are associated with non-type I disease. In Israel, cystinuria is especially common among Libyan Jews who suffer from non-type I disease. OBJECTIVES: To compare clinical manifestations of patients with mutations in SLC3A1 to those with mutations in SLC7A9, and to assess the carrier rate among unaffected Libyan Jewish controls. METHODS: Clinical manifestations were evaluated in patients with mutations in SLC3A1 and in patients with mutations in SLC7A9. Carrier rates for two SLC7A9 mutations were assessed in 287 unaffected Libyan Jewish controls. RESULTS: Twelve patients with mutations in SLC3A1 were compared to 15 patients with mutations in SLC7A9. No differences were detected between the patients with mutations in SLC3A1 and those with mutations in SLC7A9 in relation to the age of disease onset, the estimated number of stones, the number of invasive procedures, the number of patients receiving drug therapy, or the patients' urinary pH. Eleven of the unaffected Libyan Jewish controls were found to be heterozygotes for the V170M mutation, establishing a carrier rate of 1:25. The 1584 + 3 del AAGT mutation was not found in any of the Libyan Jewish controls. CONCLUSION: Mutations in SLC3A1 and SLC7A9 cystinuria patients result in indistinguishable disease manifestations. The high carrier rate among Libyan Jews is a result of a single missense mutation, V170M.

Megalencephalic leukoencephalopathy with subcortical cysts; a founder effect in Israeli patients and a higher than expected carrier rate among Libyan Jews.

Megalencephalic leukoencephalopathy with subcortical cysts (MLC) is a progressive inherited neurological disorder characterized by macrocephaly, deterioration in motor functions and cerebellar ataxia. In Israel the disease is found in an increased frequency among Libyan Jews. The disease is caused by mutations in the MLC1 gene, which encodes a putative CNS membrane transporter. We describe three novel mutations (p.G59E, p.P92S, and 134_136insC) in seven MLC families. One of these mutations, p.G59E, was found in the vast majority of MLC patients in Israel. Screening of 200 normal Libyan Jewish individuals for the p.G59E mutation, revealed a carrier rate of 1/40 compared with an expected carrier rate of 1/81. Several explanations could account for this difference the most likely one is an admixture of the Libyan Jewish population.