Last reviewed 2026-04-23 · How we verify

RHB-104

RHB-104 is a combination of three antibiotics (clarithromycin, rifabutin, and clofazimine) designed to target Mycobacterium avium subspecies paratuberculosis (MAP) in Crohn's disease.

RHB-104 is a combination of three antibiotics (clarithromycin, rifabutin, and clofazimine) designed to target Mycobacterium avium subspecies paratuberculosis (MAP) in Crohn's disease. Used for Crohn's disease (moderate to severe, MAP-positive or MAP-negative).

At a glance

Mechanism of action

RHB-104 combines antimicrobial agents with activity against intracellular bacteria, particularly MAP, which has been hypothesized to play a role in Crohn's disease pathogenesis. The triple-drug combination aims to achieve synergistic bacterial killing while minimizing resistance development. The rationale is based on the theory that MAP infection may trigger or perpetuate chronic intestinal inflammation in genetically susceptible individuals.

Approved indications

• Crohn's disease (moderate to severe, MAP-positive or MAP-negative)

Common side effects

• Gastrointestinal disturbances
• Nausea
• Abdominal pain
• Diarrhea
• Discoloration of skin/body fluids

Key clinical trials

• Open Label Efficacy and Safety of Anti-MAP (Mycobacterium Avium Ssp. Paratuberculosis) Therapy in Adult Crohn's Disease (PHASE3)
• Efficacy and Safety of Anti-MAP Therapy in Adult Crohn's Disease (PHASE3)
• Proof of Concept Study of RHB-104 as Add-On Therapy to Interferon Beta-1a in Relapsing Remitting Multiple Sclerosis (RRMS) (PHASE2)

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:

• RHB-104 CI brief — competitive landscape report
• RHB-104 updates RSS · CI watch RSS
• RedHill Biopharma Limited portfolio CI