Results
Forty-seven subjects underwent medical screening. Twenty-four subjects
(male:female ratio 1:1) with Fitzpatrick skin type II were administered
40 mg adalimumab (volume of 0.4 mL) i.d. or s.c. in the lateral upper
thigh and placebo (volume of 0.4 mL) s.c. or i.d. in the contralateral
thigh. One subject was randomized but excluded before treatment due to
medical reasons and replaced (Figure 1 ). The mean age was 26.1
years (range 20-42). Demographic characteristics were comparable between
groups (Table 1 ). For both s.c. and i.d. adalimumab injections
a minor spill (1-15% of intended volume not injected) occurred in 2 of
12 (17%) injections, and there was one (8%) major spill (15-50% of
intended volume not injected) in an i.d. adalimumab injection. Both the
minor spills and the major spill during i.d. injection occurred when
high resistance during injection was encountered, whereas the minor
spill of s.c. injection was due to backflow. Inspection of the hollow
microneedles after injection using bright field microscopy did not show
damaged microneedle tips (not shown).