Hi Flsun01 and welcome to the forum.

Maybe I can help a little with your question but the synopsis below is not intended to be comprehensive or all inclusive, rather some highlites and links to other leading sites. You're correct that the drug is in trials (now Phase III) at Cornell-Weill Presbyterian Hospital in NY. Hope this helps a little.

http://care.diabetesjournals.org/cgi/reprint/29/1/68


Ranirestat is a potent aldose reductase inhibitor (ARI) in development at Dainippon Pharma (Japan) to treat diabetic sensorimotor polyneuropathy (DSP). ARI’s are thought to act by inhibiting the polyol pathway leading to nerve damage. This is important because in diabetics prolonged hyperglycemia exacerbates ADR activity which in turn leads to increased conversion of glucose to polyols, e.g. sorbitol. Accumulation of sorbitol and fructose in nerve cells leads to damage.

The initial phase II study evaluated patients randomized at 5mg/day and 20mg/day and was 12 weeks which was extended to 60wks to further assess efficacy of the treatment program.

Ranirestat was further evaluated in a small (~90 patient population) multi-center, double-blinded, randomized trial to assess the efficacy of a higher dose – the study was conducted at Toronto General Hospital, Toronto, Canada.

In the initial study there were significant reductions in nerve sorbitol concentrations at both does of ranirestat vs placebo controls. Results were ascertained by NCS (nerve conduction study) and VPT (vibration perception threshold) which were performed at 12 weeks to assess outcome and then at 60 weeks.

The study directors concluded that @ a 20mg/day dose, ranirestat maintained the improved nerve function seen at 12 weeks through 60 weeks as measured by NCV and VPT. Sensory nerve function was maintained and motor nerve function was improved.

The authors noted their findings agreed with those reported for another ARI, zanarestat in which decreases in sorbitol concentrations led to increased density of small diameter sural nerve myelinated fibers. HOWEVER, the authors also noted that their results need to be confirmed in a placebo controlled trial of long duration, e.g. 12 months which carries more statistical weight. Nonetheless, the results confirm that the polyol pathway is a major contributor to DSP.

http://news.med.cornell.edu/wcmc/wcm...06_09_05.shtml

http://www.medscape.com/viewarticle/520964

http://www.jhasim.com/files/articlef...A_p264_269.pdf

http://forum.lowcarber.org/showthread.php?t=253227

This area has been around for ~40years now since the importance of the polyol pathway in DSP was discussed in the late '60's.

Alkymst