Ruboxistaurin for the Treatment of Diabetic Peripheral Neuropathy: A Systematic Review of Randomized Clinical Trials

BACKGROUND: Diabetic peripheral neuropathy (DPN) is a common complication of diabetes mellitus. Protein kinase C (PKC) inhibitor's has been thought to be a potential disease modifying drug's in DPN as it slows or reverse neuropathy's progression. To assesses the efficacy and safety of ruboxistaurin on the progression of symptoms, signs, or functional disability in DPN. METHODS: A systematic review of the literature databases like PubMed, ProQuest, EBSCO, EMBASE, and Cochrane Central was performed up to August 2012. We included randomized controlled trials (RCTs) comparing PKC inhibitor ruboxistaurin (RBX) with control and lasting at least 6 months. Our primary outcome measure was change in neurological examination, measured by neurological total symptom score (NTSS) and vibration detection threshold (VDT). Secondary outcome measures were total quality of life (QoL), skin microvascular blood flow and others. RESULTS: Six RCTs were included in review. Change in neurological function assessed by NTSS was reported in six studies, out of which significant difference between the RBX and placebo group seen in four studies favouring treatment group while remaining two studies reported no significant difference. VDT was assessed in only one study in which no significant difference seen between RBX and placebo group. Two studies reported significant improvement in QoL data. Safety data was reported in only two studies in which none of side effect was related to RBX. CONCLUSION: RBX had effects on DPN in some studies, but the evidence is not enough for meta-analysis and firm conclusion.