Last reviewed 2026-04-19 · How we verify

Odalasvir 75 mg

Odalasvir inhibits hepatitis C virus NS5A protein to block viral replication and assembly.

Odalasvir 75 mg is a hepatitis C virus (HCV) NS5A inhibitor developed by Janssen Research & Development that was discontinued before FDA approval. The drug was designed to inhibit the NS5A protein, a multifunctional regulator essential for HCV replication and virion assembly, and was evaluated in combination with other direct-acting antivirals (DAAs) including simeprevir and AL-335. Clinical development included 9 trials across Phase 1 and Phase 2, with Phase 2 data demonstrating efficacy in chronic hepatitis C patients when combined with other DAAs; however, the program was terminated as the competitive HCV landscape shifted toward all-oral, fixed-dose combination regimens with superior efficacy and tolerability profiles. The discontinuation reflects the rapid evolution of HCV therapeutics and Janssen's strategic pivot away from this particular combination approach in favor of more advanced DAA regimens. No approved indications, revenue, or commercial data exist for this asset.

At a glance

Mechanism of action

Odalasvir is a direct-acting antiviral (DAA) that targets the NS5A protein of hepatitis C virus. NS5A is a multifunctional, zinc-binding phosphoprotein that plays critical roles in HCV RNA replication, virion assembly, and host cell interactions. By binding to and inhibiting NS5A, odalasvir disrupts the viral replication complex, preventing the virus from making copies of itself and assembling infectious particles. This mechanism is distinct from protease inhibitors (which block viral protein processing) and polymerase inhibitors (which block RNA synthesis), allowing odalasvir to be combined with drugs targeting other viral proteins for enhanced antiviral activity. The drug was developed as part of a multi-DAA combination strategy to achieve high cure rates in hepatitis C patients across different viral genotypes.

Approved indications

No approved indications tracked.

Pipeline indications

• Chronic hepatitis C (genotype 1) — Phase 2
• Chronic hepatitis C (treatment-naïve and treatment-experienced) — Phase 2
• Chronic hepatitis C (Japanese population) — Phase 2

Common side effects

No common side effects on file.

Drug interactions

• Simeprevir
• AL-335

Key clinical trials

• Study to Investigate the Pharmacokinetic Interaction Between 2 Direct Acting Antiviral Agents Odalasvir and AL-335 and Between 3 Direct Acting Antiviral Agents Simeprevir, Odalasvir and AL-335 at Steady State in Healthy Japanese Participants (PHASE1)
• A Pharmacokinetic Interaction Study Between Odalasvir, Given as a Single Agent or in Combination With Simeprevir, and Dabigatran Etexilate Mesylate in Healthy Participants (PHASE1)
• Efficacy and Safety of Combinations of AL-335, Odalasvir (ODV) and Simeprevir (SMV) in the Treatment of Chronic Hepatitis C Infection (PHASE2)
• A Study to Investigate the Safety, Pharmacokinetics, and Efficacy of Combination Treatment of AL-335, Odalasvir, and Simeprevir in Japanese Participants With Chronic Hepatitis C Genotype 1 or 2 Virus Infection, With or Without Compensated Cirrhosis Who Are Direct Acting Antiviral Treatment-naive (PHASE2)
• A Study to Evaluate the Safety, Pharmacokinetics and Efficacy of the Combination of AL-335, Odalasvir, and Simeprevir (PHASE2)
• Study to Assess the Relative Bioavailability of Fixed-Dose Combination (FDC) Tablet (Simeprevir, Odalasvir and AL-335) Compared With Single Agents Administered Together, and to Assess the Effect of Multiple-Dose Lansoprazole or Omeprazole on Single-Dose Pharmacokinetics of SMV, ODV, and AL-335 (FDC) (PHASE1)
• A Study to Evaluate the Cardiac Safety of a Single Dose of AL-335 Administered on a Background of Simeprevir and Odalasvir and of Repeated Doses of Odalasvir Administered Alone in Healthy Participants (PHASE1)
• A Study to Investigate the Pharmacokinetics, Safety, and Tolerability of Odalasvir and AL-335 Alone and in Combination With Simeprevir in Participants With Moderately Impaired Hepatic Function (PHASE1)

Primary sources

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