Last reviewed 2026-04-22 · How we verify

Placebo comparator - Microcrystalline cellulose

Microcrystalline cellulose is an inert, insoluble polysaccharide that serves as a placebo comparator and has no active pharmacological mechanism.

Microcrystalline cellulose is an inert, insoluble polysaccharide that serves as a placebo comparator and has no active pharmacological mechanism. Used for Placebo comparator in clinical trials (non-therapeutic use).

At a glance

Mechanism of action

Microcrystalline cellulose is a purified, partially depolymerized cellulose commonly used as an inactive pharmaceutical excipient and placebo control in clinical trials. It is poorly absorbed in the gastrointestinal tract and passes through largely unchanged, providing no therapeutic effect. Its use as a placebo comparator allows for blinded assessment of investigational drug efficacy against an inert control.

Approved indications

• Placebo comparator in clinical trials (non-therapeutic use)

Common side effects

• Gastrointestinal disturbance (minimal, attributable to vehicle)
• No clinically significant adverse events expected

Key clinical trials

• Adenosine 2A Receptor Antagonism and AIH in ALS (PHASE1, PHASE2)
• IRELAnD: Investigating the Role of Early Low-dose Aspirin in Diabetes (PHASE3)
• Magnesium Supplementation in Advanced Non-small Cell Lung Cancer (NSCLC) (PHASE2, PHASE3)
• Effect of Oral Microbiota on MDRO Decolonization (PHASE1, PHASE2)
• Bisnorcymserine in Healthy Adult Volunteers (PHASE1)
• First-in-Human Study of VNT-101: Safety, Tolerability, and Pharmacokinetics (PHASE1)
• VE303 for Prevention of Recurrent Clostridioides Difficile Infection (PHASE3)
• Milk Volume Outcomes Following Oral Nicotinamide Riboside Supplementation in Mothers of Extremely Preterm Infants (PHASE2, PHASE3)

Primary sources

Every claim on this page is sourced from regulatory or scientific primary sources. See our editorial policy for full methodology.