INTRODUCTION: Polyneuropathy, organomegaly, endocrinopathy, M-protein and skin 
changes (POEMS) syndrome is a fatal systemic disorder associated with plasma 
cell dyscrasia and the overproduction of the vascular endothelial growth factor 
(VEGF). Recently, the prognosis of POEMS was substantially improved by 
introduction of therapeutic intervention for myeloma. However, no randomised 
clinical trial has been performed because of the rarity and severity of the 
disease.
METHODS AND ANALYSIS: The Japanese POEMS syndrome with Thalidomide (J-POST) 
Trial is a phase II/III multicentre, double-blinded, randomised, controlled 
trial that aims to evaluate the efficacy and safety of a 24-week treatment with 
thalidomide in POEMS syndrome, with an additional 48-week open-label safety 
study. Adults with POEMS syndrome who have no indication for transplantation are 
assessed for eligibility at 12 tertiary neurology centres in Japan. Patients who 
satisfy the eligibility criteria are randomised (1:1) to receive thalidomide 
(100-300 mg daily) plus dexamethasone (12 mg/m(2) on days 1-4 of a 28-day cycle) 
or placebo plus dexamethasone. Both treatments were administered for 24 weeks 
(six cycles; randomised comparative study period). Patients who complete the 
randomised study period or show subacute deterioration during the randomised 
period participate in the subsequent 48-week open-label safety study (long-term 
safety period). The primary end point of the study is the reduction rate of 
serum VEGF levels at 24 weeks.
ETHICS AND DISSEMINATION: The protocol was approved by the Institutional Review 
Board of each hospital. The trial was notified and registered at the 
Pharmaceutical and Medical Devices Agency, Japan (No. 22-1716). The J-POST Trial 
is currently ongoing and is due to finish in August 2015. The findings of this 
trial will be disseminated through peer-reviewed publications and conference 
presentations and will also be disseminated to participants.
TRIAL REGISTRATION NUMBER: UMIN000004179 and JMA-IIA00046.