In the last decade new and more advanced microvascular imaging techniques have become available for use in clinical research. As it became more evident that microvascular dysfunction might prelude (cardio) vascular events, microvascular measurements have gained increasing interest for their applicability in the clinic and research. In this narrative review we aim to provide an updated oversight of microvascular measurement techniques. We have made an outline of the most common and latest techniques for microvascular cutaneous and retinal measurements and included the most frequently used challenges used together with these measurements. Furthermore this review includes an updated evaluation of the mechanistic background of microcirculatory dysfunction. Hereby this narrative literature review aims to assist with the identification of the most adequate microvascular imaging technique(s) for clinical application and research

Aim To evaluate feasibility of intradermal (i.d.) adalimumab administration using hollow microneedles, and to compare a single i.d. dose of adalimumab using a hollow microneedle with a single subcutaneous (s.c.) dose using a conventional needle. Methods In this single-centre double-blind, placebo-controlled, double-dummy clinical trial in 24 healthy adults we compared 40 mg adalimumab (0.4 mL) administered i.d. using a hollow microneedle with a s.c. dose using a conventional needle. Primary parameters were pain, acceptability, and local tolerability; secondary parameters safety, pharmacokinetics and immunogenicity. We explored usability of optical coherence tomography (OCT), clinical photography, thermal imaging, and laser speckle contrast imaging (LSCI) to evaluate skin reaction after i.d. injections. In vitro protein analysis was performed to assess compatibility of adalimumab with the hollow microneedle device. Results While feasible and safe, injection pain of i.d. adalimumab was higher compared to s.c. adalimumab (35.4 vs. 7.9 on a 101-point VAS scale). Initial absorption rate and bioavailability were higher after i.d. adalimumab (Tmax=95h(47-120); F=129%(6.46%)) compared to s.c. adalimumab (Tmax=120h(96-221)). In 50% and 83% of the subjects anti-adalimumab antibodies were detected after i.d. and s.c. adalimumab, respectively. We observed statistically significantly more erythema and skin perfusion after i.d. adalimumab, compared to s.c. adalimumab and placebo injections (p<0.0001). Cytokine secretion after whole blood LPS challenge was comparable between administration routes. Conclusion Intradermal of adalimumab using hollowing microneedles was perceived as more painful, and less accepted than s.c. administration, however, yields a higher bioavailability with similar safety and pharmacodynamic effects.

Aim: To investigate the safety, tolerability, pharmacokinetics (PK) and pharmacodynamics (PD) of the highly selective oral p38α/β MAP-kinase inhibitor Org 48775-0, a first-in-human study was conducted. Methods: In the SAD study part, an oral dose of Org 48775-0 ranging from 0.3 mg to 600 mg was evaluated in healthy males. In the MAD study part, dose levels of 30, 70 and 150 mg were evaluated with dosing for six consecutive days, twice daily. Both studies were performed in a double-blind, randomized, placebo-controlled, cross-over fashion and evaluated pharmacokinetics (PK), pharmacodynamics (PD; inhibition of LPS-induced TNFα release) and routine clinical and laboratory data. Moreover, the effect of a standardized fat meal on PK and PD parameters of Org 48775-0 was evaluated, and PK and PD parameters of Org 48775-0 were compared between healthy males and postmenopausal females. Results: All adverse events observed in the SAD and MAD cohorts were mild, transient and completely reversible without medical intervention. Pharmacokinetics were linear up to single dose s of 400 mg. Org 48775-0 doses equal to and greater than 30 mg significantly inhibited LPS-induced TNFα release (42.3% increase in inhibition, 95% CI=-65.2; -4.3) compared to placebo. In the MAD study, Org 48775-0 treatment inhibited the LPS-induced TNFα release during the entire steady state period. Levels of inhibition amounted 30-75% for 30 mg, 53-80% for 70 mg, and 77-92% for 150 mg Org 48775-0. Conclusion: This study demonstrates that Org 48775-0 has the capacity to significantly inhibit MAP-kinase activity in humans, without raising safety concerns.