Quality of life and patient benefit following transition from methotrexate to ustekinumab in psoriasis

BACKGROUND

TRANSIT (NCT01059773) compared immediate and gradual transition from methotrexate to ustekinumab in psoriasis patients via multiple measures, including patient-reported outcomes.

OBJECTIVE

To evaluate patient perception of treatment benefits in TRANSIT.

METHODS

A total of 489 psoriasis patients received ustekinumab, with immediate cessation of methotrexate (Arm 1) or 4 weeks' overlap with decreasing methotrexate dose (Arm 2). Ustekinumab was administered at weeks 0, 4, 16, 28 and 40. Dermatology Life Quality Index (DLQI), EuroQol 5-item (EQ-5D), visual analogue scale (VAS) valuation technique and patient benefit index (PBI) were employed. Mean global PBI and sub-scores were calculated from the sum of the benefit items weighted by their respective relevance at baseline. Patient-relevant benefit was defined as PBI ≥1 (scale: 0 [no benefit] to 4 [maximum benefit]). Correlations of global PBI with Psoriasis Area and Severity Index (PASI) and DLQI were examined.

RESULTS

Relationships between PBI and clinical data were evaluable in 340 patients. The most important treatment goals at baseline included: 'be healed of all skin defects', 'have confidence in therapy', 'get better skin quickly' and 'regain control of the disease'. Benefit in PBI global score was achieved at week 4 by 93% of patients in Arm 1 and 91% in Arm 2. Global PBI scores increased in both Arms between weeks 4 and 52. Global PBI correlated weakly with PASI change from baseline (correlation coefficient range: -0.22 to -0.40), and moderately with DLQI (-0.29 to -0.54). Overall DLQI score was lower than baseline at all times; and the percentage of patients with an overall score of 0 or 1 increased with time. Correspondingly, EQ VAS scores increased with time. DLQI and EQ VAS results were similar between arms.

CONCLUSIONS

Regardless of the strategy for transitioning from methotrexate, ustekinumab was associated with rapid and sustained improvement in patient-reported outcomes. PBI appears a suitable tool for assessing patient-relevant treatment benefits in psoriasis patients.

Ultrasound-mediated intracellular drug delivery using microbubbles and temperature-sensitive liposomes

A novel two-step protocol for intracellular drug delivery has been evaluated in vitro. As a first step TO-PRO-3 (a cell-impermeable dye that displays a strong fluorescence enhancement upon binding to nucleic acids) encapsulated in thermosensitive liposomes was released after heating to 42°C. A second step consisted of ultrasound-mediated local permeabilization of cell membrane allowing TO-PRO-3 internalization observable as nuclear staining. Only the combination of two consecutive steps - heating and sonication in the presence of SonoVue microbubbles led to the model drug TO-PRO-3 release from the thermosensitive liposomes and its intracellular uptake. This protocol is potentially beneficial for the intracellular delivery of cell impermeable drugs that suffer from rapid clearance and/or degradation in blood and are not intrinsically taken up by cells.

Magnetic control of vascular network formation with magnetically labeled endothelial progenitor cells

We describe the applications of new cellular magnetic labeling method to endothelial progenitor cells (EPC), which have therapeutic potential for revascularization. Via their negative surface charges, anionic magnetic nanoparticles adsorb non-specifically to the EPC plasma membrane, thereby triggering efficient spontaneous endocytosis. The label is non-toxic and does not affect the cells' proliferative capacity. The expression of major membrane proteins involved in neovascularisation is preserved. Labeled cells continue to differentiate in vitro and to form tubular structures in Matrigel (an in vitro model of neovascularization). This process was followed in situ by using high-resolution MRI. Finally, we show that magnetic forces can be used to move magnetically labeled EPC in vitro and to modify their organization in Matrigel both in vitro an in vivo. Magnetic cell targeting opens up new possibilities for vascular tissue engineering and for delivering localized cell-based therapies.

Single-cell detection by gradient echo 9.4 T MRI: a parametric study

Recent studies have shown that cell migration can be monitored in vivo by magnetic resonance imaging after intracellular contrast agent incorporation. This is due to the dephasing effect on proton magnetization of the local magnetic field created by a labelled cell. Anionic iron oxide nanoparticles (AMNP) are among the most efficient and non-toxic contrast agents to be spontaneously taken up by a wide variety of cells. Here we measured the iron load and magnetization of HeLa tumour cells labelled with AMNP, as a function of the external magnetic field. High-resolution gradient echo 9.4 T MRI detected individual labelled cells, whereas spin echo sequences were poorly sensitive. We then conducted a systematic study in order to determine the gradient echo sequence parameters (echo time, cell magnetization and resolution) most suitable for in vivo identification of single cells.

Spatial and temporal control of transgene expression in vivo using a heat-sensitive promoter and MRI-guided focused ultrasound

BACKGROUND

Among the techniques used to induce and control gene expression, a non-invasive, physical approach based on local heat in combination with a heat-sensitive promoter represents a promising alternative but requires accurate temperature control in vivo. MRI-guided focused ultrasound (MRI-FUS) with real-time feedback control allows automatic execution of a predefined temperature-time trajectory. The purpose of this study was to demonstrate temporal and spatial control of transgene expression based on a well-defined local hyperthermia generated by MRI-FUS.

METHODS

Expression of the green fluorescent protein (GFP) marker gene was used. Two cell lines were derived from C6 glioma cells. The GFP expression of the first one is under the control of the CMV promoter, whereas it is under the control of the HSP70 promoter in the second one and thus inducible by heat. Subcutaneous tumours were generated by injection in immuno-deficient mice and rats. Tumours were subjected to temperatures varying from 42 to 50 degrees C for 3 to 25 min controlled by MRI-FUS and analyzed 24 h after the heat-shock. Endogenous HSP70 expression and C6 cell distribution were also analyzed.

RESULTS

The results demonstrate strong expression at 50 degrees C applied during a short time period (3 min) without affecting cell viability. Induced expression was also clearly shown for temperature in the range 44-48 degrees C but not at 42 degrees C.

CONCLUSIONS

Heating with MRI-FUS allows a tight and non-invasive control of transgene expression in a tumour.