Last reviewed 2026-04-23 · How we verify

ranirestat, (AS-3201)

Ranirestat inhibits aldose reductase, the first enzyme in the polyol pathway, to reduce sorbitol accumulation and prevent diabetic complications.

Ranirestat inhibits aldose reductase, the first enzyme in the polyol pathway, to reduce sorbitol accumulation and prevent diabetic complications. Used for Diabetic peripheral neuropathy, Diabetic complications (retinopathy, nephropathy).

At a glance

Mechanism of action

Ranirestat is an aldose reductase inhibitor that blocks the conversion of glucose to sorbitol via the polyol pathway. By reducing sorbitol accumulation in tissues, it aims to prevent or slow the progression of diabetic microvascular complications such as peripheral neuropathy, retinopathy, and nephropathy. This mechanism addresses a key metabolic pathway implicated in diabetes-related tissue damage.

Approved indications

• Diabetic peripheral neuropathy
• Diabetic complications (retinopathy, nephropathy)

Common side effects

• Hepatotoxicity / elevated liver enzymes
• Gastrointestinal disturbances
• Rash / dermatological reactions

Key clinical trials

• Evaluating the Efficacy and Safety of Oral Ranirestat (40 and 80 mg) in Mild to Moderate Diabetic Sensorimotor Polyneuropathy (PHASE2, PHASE3)
• Safety and Efficacy of AS-3201 in the Treatment of Diabetic Sensorimotor Polyneuropathy (PHASE3)

Primary sources

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Competitive intelligence

For the full competitive landscape — auto-detected comparators, recent regulatory actions across the set, upcoming PDUFA, patent timeline, sponsor landscape:

• ranirestat, (AS-3201) CI brief — competitive landscape report
• ranirestat, (AS-3201) updates RSS · CI watch RSS
• Sumitomo Pharma Co., Ltd. portfolio CI