Last reviewed 2026-04-23 · How we verify

Placebo (PLB) Injectable

Placebo is an inert injectable formulation used as a control comparator in clinical trials to establish the efficacy of investigational therapeutics through blinded comparison.

Placebo is an inert injectable formulation used as a control comparator in clinical trials to establish the efficacy of investigational therapeutics through blinded comparison. Used for Clinical trial control arm (indication-dependent on parent study).

At a glance

Mechanism of action

Placebo contains no active pharmaceutical ingredient and serves as a negative control in randomized controlled trials. By comparing patient outcomes between placebo and active drug groups, researchers can isolate the true therapeutic effect of the investigational agent from natural disease progression and psychological expectation effects. Placebo is essential for establishing statistical significance and regulatory approval of new drugs.

Approved indications

• Clinical trial control arm (indication-dependent on parent study)

Common side effects

• Injection site reactions
• Nocebo effects (adverse events attributed to expectation)

Key clinical trials

• Trial of Naltrexone/Bupropion for the Treatment of Methamphetamine Use Disorder (PHASE3)
• Extended-Release Naltrexone and Monthly Extended-Release Buprenorphine for Cocaine Use Disorder (CURB-2) (PHASE2)
• Cocaine Use Reduction With Buprenorphine (PHASE2, PHASE3)
• Accelerated Development of Additive Pharmacotherapy Treatment (ADAPT-2) for Methamphetamine Use Disorder (PHASE3)

Primary sources

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