A pilot study on the use of prednisolone-encapsulated liposomes for the treatment of moderate-to-severe Graves' orbitopathy with reduced systemic steroid exposure.

PURPOSE: To demonstrate that long-circulating PEGylated liposomal prednisolone is a safe and effective therapy in patients with active moderate-to-severe Graves' orbitopathy. METHODS: Open-label, proof-of-concept, multicentre pilot study. Ten patients with moderate-to-severe Graves's orbitopathy, who were euthyroid for at least three months. Long-circulating PEGylated liposomal prednisolone 150 mg was administered intravenously twice, with 2-week interval. Total follow-up was 12 months, with visits at baseline, week 2, 6, 13, 26 and 52. Physical, laboratory and ophthalmological examinations were performed. Response to treatment was defined as a reduction in Clinical Activity Score by ≥2 points; palpebral aperture by ≥3 mm; soft tissue signs by ≥2 grades; exophthalmos by ≥2 mm; and motility by >8 degrees or improvement in diplopia score. A response was sustained when equally observed at weeks 6 and 13. RESULTS: One patient achieved a sustained response according to the predetermined definition. All patients showed a decrease in Clinical Activity Score after one infusion, with a mean decrease of two points. The Clinical Activity Score was ≤1 at week 52 for all patients. Improvement was also observed in the soft tissue signs. Most of the adverse events were mild and of a transient nature. Two patients required further treatment with intravenous methylprednisolone. CONCLUSION: This pilot study showed a positive effect of long-circulating PEGylated liposomal prednisolone on the Clinical Activity Score in patients with moderate-to-severe Graves's orbitopathy, resulting in fewer hospital visits and possibly less glucocorticoid-related side-effects.

The role of functional health literacy in long-term treatment outcomes in psychosocial care for adolescents.

Although among adolescents with psychosocial problems low health literacy may increase the risk of poor treatment outcomes, the contributing mechanisms within treatment remain unclear. A better understanding of these mechanisms could contribute to improved treatment processes and outcomes. This study aims to examine the relationship between functional health literacy, treatment processes (treatment adherence, learning processes), and treatment outcome (level of psychosocial problems) in adolescents in psychosocial care. We used data from a prospective cohort study among adolescents aged 12-18 (N = 390), collected in four successive measurements: at entry into care, and 3, 12, and 24 months thereafter. We used a mixed effect model to investigate the association between level of functional health literacy (adequate vs. inadequate) and treatment processes (treatment adherence, learning processes) and treatment outcome (level of psychosocial problems). Between adolescents with adequate and inadequate functional health literacy, we found no differences or change over time in adherence or learning processes. The level of psychosocial problems significantly declined over time (ß = - 1.70, 95% CI [- 2.72, - 0.69], p = .001) to a similar degree in both groups, though, in all measurements, the level was consistently higher for adolescents with inadequate health literacy. We conclude that health literacy levels did not affect change in treatment processes nor in outcomes of psychosocial treatment. However, the consistently higher level of psychosocial problems among adolescents with inadequate health literacy suggests an unaddressed need in psychosocial care.

Overcoming multidrug resistance using folate receptor-targeted and pH-responsive polymeric nanogels containing covalently entrapped doxorubicin.

Multidrug resistance (MDR) contributes to failure of chemotherapy. We here show that biodegradable polymeric nanogels are able to overcome MDR via folic acid targeting. The nanogels are based on hydroxyethyl methacrylamide-oligoglycolates-derivatized poly(hydroxyethyl methacrylamide-co-N-(2-azidoethyl)methacrylamide) (p(HEMAm-co-AzEMAm)-Gly-HEMAm), covalently loaded with the chemotherapeutic drug doxorubicin (DOX) and subsequently decorated with a folic acid-PEG conjugate via copper-free click chemistry. pH-Responsive drug release is achieved via the acid-labile hydrazone bond between DOX and the methacrylamide polymeric network. Cellular uptake and cytotoxicity analyses in folate receptor-positive B16F10 melanoma versus folate receptor-negative A549 lung carcinoma cells confirmed specific uptake of the targeted nanogels. Confocal microscopy demonstrated efficient internalization, lysosomal trafficking, drug release and nuclear localization of DOX. We also show that DOX resistance in 4T1 breast cancer cells results in upregulation of the folate receptor, and that folic acid targeted nanogels can be employed to bypass drug efflux pumps, resulting in highly efficient killing of resistant cancer cells. In conclusion, folic acid functionalized nanogels with pH-controlled drug release seem to hold significant potential for treating multidrug resistant malignancies.

Liposomal targeting of glucocorticoids to synovial lining cells strongly increases therapeutic benefit in collagen type II arthritis.

OBJECTIVE: To investigate the effect of a single intravenous treatment with glucocorticoids (GC) encapsulated in long-circulating PEG-liposomes on both joint inflammation and cartilage destruction and to investigate the phenomenon of selective homing of these liposomes in the inflamed synovium. METHODS: Mice with collagen type II-induced arthritis (CIA) were intravenously treated with liposomal and free prednisolone phosphate (PLP) a few days after the first signs of the disease. Joint inflammation was scored during 1 week after treatment, after which sections of the knee joints were prepared for assessment of cartilage damage. In addition, arthritic mice were treated with liposomes containing colloidal gold. 24 hours after injection, knee joint sections were prepared in which the location of liposomes was visualised. RESULTS: Treatment of CIA with 10 mg/kg liposomal PLP resulted in a strong and lasting resolution of joint inflammation. 10 mg/kg free PLP only became slightly effective after repeated daily injections. Although joint inflammation recurred 1 week after treatment with liposomal PLP, knee joint sections prepared at this time indicated that the cartilage damage was still reduced. Localisation of gold labelled liposomes in the inflamed joints was seen in the proximity of blood vessels, in the cellular infiltrate, but mainly in the synovial lining. Unaffected joints did not take up liposomes. CONCLUSIONS: By using the property of long-circulating liposomes to target the synovial lining selectively in inflamed joints, the anti-inflammatory activity of GC can be greatly increased, showing also the beneficial effect of reduced cartilage destruction.

Liposomes for intravenous drug targeting: design and applications.

Drug targeting with liposomes has been studied for over 25 years and has demonstrated its value in clinical practice. This mini review offers an overview of the design and application of liposomes for i.v. drug targeting. Two approaches are outlined: passive and active targeting. The former approach is based on liposomes with prolonged circulation and selective target localization properties, while in the latter approach specific targeting ligands are coupled to the liposome surface in order to achieve enhanced interaction with target cell membranes.

Role of complement activation in hypersensitivity reactions to doxil and hynic PEG liposomes: experimental and clinical studies.

Pegylated liposomal doxorubicin (Doxil) and 99mTc-HYNIC PEG liposomes (HPL) were reported earlier to cause hypersensitivity reactions (HSRs) in a substantial percentage of patients treated i.v. with these formulations. Here we report that (1) Doxil, HPL, pegylated phosphatidylethanolamine (PEG-PE)-containing empty liposomes matched with Doxil and HPL in size and lipid composition, and phosphatidylglycerol (PG)-containing negatively charged vesicles were potent C activators in human serum in vitro, whereas small neutral liposomes caused no C activation. (2) Doxil and other size-matched PEG-PE and/or PG-containing liposomes also caused massive cardiopulmonary distress with anaphylactoid shock in pigs via C activation, whereas equivalent neutral liposomes caused no hemodynamic changes. (3) A clinical study showed more frequent and greater C activation in patients displaying HSR than in non-reactive patients. These data suggest that liposome-induced HSRs in susceptible individuals may be due to C activation, which, in turn, is due to the presence of negatively charged PEG-PE in these vesicles.

Generation of a fast and homogeneous temperature step.

A method is described for the fast and homogeneous increase of the temperature of a biological specimen with a volume of 1 mm3 or less. Heating is obtained by joule dissipation from a 30 MHz alternating current. The step quality is determined by measuring the temporal and spatial behaviour of the temperature after a power pulse in and around the biological preparation. With the described equipment a temperature step of 3 degrees C can be obtained in 8 ms. The temperature step inhomogeneity is less than 15%. The compatibility of the method with electrophysiological and mechanical measurement and instrumentation is demonstrated by the detection of transients in transmembrane potential and force of a papillary muscle from the rabbit heart.