ADA: A ‘Breakthrough’ for Diabetic Peripheral Neuropathy

LY333531, is the first drug to attack the cause of nerve-damaging diabetic peripheral neuropathy. LY333531 inhibits PKC-beta, an enzyme involved in the process of microvascular damage.
"Treating glucose variations and offering symptom relief has been about all we could for our patients up to this point," said Aaron Vinik, M.D., professor of internal medicine at Eastern Virginia Medical Center in Norfolk, United States. "We found that LY333531 gets to the root of the function of PKC-beta activity. With LY333531, we believe that we are getting at the bottom of the disease process, and we can begin to modify that process rather than just treat its destructive and painful symptoms."

Symptoms of peripheral neuropathy include numbness, prickling, aching pain, burning pain, and allodynia or lancing pain caused by ordinary skin-object contact. Over half of all diabetics develop diabetic peripheral neuropathy, according to the International Diabetes Federation. There is no FDA-approved treatment for the underlying process of microvascular damage causing diabetic peripheral neuropathy.

In a year-long, double-blind, placebo-controlled trial, Dr. Vinik and his research team randomized 205 Type 1 and Type 2 diabetics with peripheral neuropathy to receive LY333531 at 32mg/day, 64mg/day or to receive a placebo. At both dosages, LY333531 improved neurological examination scores, notably in the limbs and reflexes most affected by diabetic peripheral neuropathy. These positive findings were corroborated by a battery of other standardized tests.

"This is a potential breakthrough in diabetes treatment," said Anne Meyer, M.D., an endocrinologist and diabetes specialist practicing in San Francisco. "We can really begin for the first time to talk about stopping and healing nerve damage caused by this terrible disease."

Based upon results collected to date, the manufacturer of the compound, Eli Lilly and Company, will conduct three new global trials studying diabetic peripheral neuropathy. This will make six Phase 3 trials underway using LY333531. The three new trials will begin this year. Lilly plans to file with the FDA in 2004 for approval of LY333531 for the treatment of symptoms of diabetic peripheral neuropathy.

Lilly is also investigating the PKC-beta inhibitor as a treatment for diabetic retinopathy and diabetic macular edema, microvascular complications that can lead to blindness. American Diabetes Association’s 62nd Annual Scientific Sessions