Carnosine and Cognitive Training in Schizophrenia

What Was Tested

This registered phase 2, phase 3 trial tested Carnosine.

This is a double-blind placebo-controlled trial to evaluate the effects of the combination of a cognition enhancing drug, i.e carnosine, with cognitive training in patients with schizophrenia.

All participants will receive the same cognitive training sessions and will be randomised to either carnosine or placebo for the duration of the combined treatment period (2 weeks).

Before combined training and carnosine/placebo, there is a two-week carnosine/placebo only phase to examine the effects of carnosine alone on functioning without training.

It had two arms (groups): L-Carnosine (experimental) and Placebo (placebo comparator).

Matching placebo.

The registry classes the interventions as behavioral and drug.

More on the Plan

Compromised cognitive functioning is a core feature of schizophrenia, yet it remains a major unmet need in the treatment of schizophrenia.

The investigators propose a novel approach to enhance cognition in schizophrenia: combining a food supplement with cognitive training, rather than using each intervention alone.

Carnosine has antioxidant and antiglycating action and is found in food and the human body.

The investigator's choice is guided by several considerations but, primarily the evidence that L-carnosine has neuroprotective effects through its antioxidant features.

Who Took Part

Enrollment: 60 actual participants took part.

It was open to people of any sex aged from 18 years up to 60 years.

Healthy volunteers were not accepted; participants needed the condition being studied.

Examples of who could join: Age 18-60, males and females. Duration of illness equal to or greater than one year. Patients should be clinically stable in a non-acute phase for at least 8 weeks prior to the screening visit. Subjects must read and write in English at a level sufficient to understand and complete study- related procedures. Informed consent signed by participant.

The full record lists 8 inclusion and 8 exclusion criteria; among the exclusions: current treatment (within 4 weeks) with psychotropic agents known to effect cognition: amphetamines, barbiturates, maois, methylphenidate, benzodiazepines; pregnant or breast-feeding women; history of a serious neurological disorder or a systemic illness with known neurological complications.

How the Study Was Run

It was run as a randomized, parallel-group and quadruple-blind study.

Because people in this Carnosine study were split into groups at random, differences between the groups are less likely to reflect who happened to join each one.

The Carnosine group and the comparison group ran side by side rather than switching.

Blinding on both sides kept the participants and researchers unaware of who received Carnosine.

Those kept unaware of assignments: participant, care provider, investigator and outcomes assessor.

It started in 2015-12-01 with completion listed for 2022-07-19.

It ran at 1 site in United States.

Its stated primary purpose is treatment.

What Was Measured

Primary outcome: Cognitive Training Score (time frame: 8 weeks).

It also tracked 3 secondary outcomes, for example The Learning Rate, Change in Performance Advantage and Matrix Consensus Cognitive Battery (MCCB).

What This Means in Plain Language

Put simply, this is a phase 2, phase 3, randomized trial of Carnosine in 60 people.

The trial is marked completed; no results are posted to the registry yet, so nothing here describes outcomes.

More context: the Carnosine compound page, all human trials.