Randomized controlled trial of brain-derived neurotrophic factor in Guillain-Barré syndrome: a pilot study. CSF filtration is an effective treatment of Guillain-Barré syndrome: a randomized clinical trial. A randomized controlled trial of recombinant interferon-beta 1a in Guillain-Barré syndrome. [Effect of Tripterygium polyglycoside on interleukin-6 in patients with Guillain-Barre syndrome].
Brain-derived neurotrophic factor (BDNF) has the theoretical potential to protect neurones from axonal degeneration. The objective of this study was to discover whether brain-derived neurotrophic factor is safe in Guillain-Barré syndrome, and to make preliminary observations of its efficacy. This was a parallel group randomized controlled trial of subcutaneous brain-derived neurotrophic factor 25 microg/kg daily compared with placebo for up to 24 weeks or until patients could walk without aid. Six patients received brain-derived neurotrophic factor, of whom three had serious adverse events including one death. Four patients received placebo, of whom two had serious adverse events including one death. The rate and extent of recovery were similar in the two groups. This pilot study did not detect any serious adverse events attributed to brain-derived neurotrophic factor treatment. To compare CSF filtration (CSFF) and plasma exchange (PE) in the treatment of patients with Guillain-Barré syndrome (GBS).
                In a prospective controlled clinical trial, 37 patients with acute GBS were randomized to receive either CSFF or PE. Inclusion criteria were fulfillment of National Institute of Neurological and Communicative Disorders and Stroke criteria and disability to walk >5 m unassisted.
                With similar baseline features in both groups (initial disability grades on the six-point grading scale of the GBS Study Group) the primary outcome variable (improvement within 28 days after randomization) was almost identical (test for equivalence p = 0.0014), the mean grade values being 0.82 in the CSFF group and 0.80 in the PE group. After 56 days, 56% (9 of 16 patients) of the CSFF group and 37% (7 of 19 patients) of the PE group had reached grade 2 (i.e., ability of unassisted walking >5 m). After 6 months, the probability to reach grade 2 was about 80% in both groups. In the CSFF group, transient pleocytosis occurred without apparent clinical complications. Clinically relevant complications were higher in the PE-treated group.
                Although the number of patients was small, the authors found that the treatment of GBS with CSFF is at least as effective as with PE. CSFF might work by removing from the CSF inflammatory mediators, autoantibodies, or other factors. The authors recruited 19 nonambulant patients with Guillain-Barré syndrome into a pilot, double-blind, randomized, placebo-controlled safety trial of interferon beta 1a (IFN[beta]-1a) (Rebif). Participants received IFN[beta]-1a or placebo subcutaneously three times weekly, 22 microg for the first week and then 44 microg for up to 24 weeks, in addition to IV immunoglobulin (IVIg). IFN[beta] did not have any unexpected interaction with IVIg and there was no significant difference in rate of improvement. To study the action of interleukin-6(IL-6) in pathogenesis and effect of patients with Guillain-Barre syndrome (GBS).
                Forty-three patients of GBS were selected according to Asbury's standard and divided into two groups on layer randomize principle, they were treated with adrenal corticosteroid and Tripterygium polyglycoside (TP) respectively. Serum and cerebrospinal fluid (CSF) content of IL-6 were measured by double antibody sandwich ELISA method.
                (1) The serum and CSF content of IL-6 in GBS group was higher than those in the normal control group significantly; (2) There was positive correlation between CSF IL-6 and clinical severity (P < 0.01) before treatment; (3) After treatment the clinical symptoms were improved in both groups, but the TP treated group showed better effect than the control group in improving symptoms and lowering serum IL-6 level (P < 0.05).
                CSF level of IL-6 could be taken as one of the criteria for severity evaluation of patient's condition. TP is superior in suppressing abnormal immune reaction to adrenal corticosteroid in GBS patients.
The quality of the evidence was very low. Three small RCTs, of interferon beta-1a, brain-derived neurotrophic factor and cerebrospinal fluid filtration, showed no significant benefit or harm. A fourth small trial showed that the Chinese herbal medicine tripterygium polyglycoside hastened recovery significantly more than corticosteroids but this result needs confirmation. It was not possible to draw useful conclusions from the few observational studies.