The therapeutic potential of laquinimod for Huntington's disease: A systematic review of preclinical and clinical studies.

INTRODUCTION

Neuroinflammation is a central contributor to Huntington's disease (HD) pathogenesis and represents a promising therapeutic target. Laquinimod, an oral immunomodulator with demonstrated neuroprotective effects in preclinical models, has been investigated as a potential treatment for HD. This review critically appraises its preclinical and clinical evidence.

METHODS

A systematic search (January 2025) was conducted in PubMed, Scopus, Embase, Cochrane Library, and Web of Science using terms including "Huntington's disease," "laquinimod," and "quinoline-3-carboxylic acid." Preclinical and clinical studies evaluating laquinimod in HD were included. Due to heterogeneity, findings were synthesized qualitatively.

RESULTS

Of 2638 records identified, 10 studies met the inclusion criteria. Preclinical data showed laquinimod improved motor function, reduced neuroinflammation, and promoted myelination, likely via microglial modulation, NF-κB suppression, and increased BDNF expression. Effects on myelin integrity and inflammatory markers were inconsistent. In vitro studies showed limited, variable cytokine modulation in HD patient-derived cells. Clinical trials did not demonstrate significant improvements in motor or functional outcomes, though one study reported minor cognitive and behavioral benefits.

CONCLUSION

Preclinical evidence suggests laquinimod may modulate motor, inflammatory, and myelination pathways in HD; however, clinical evidence shows no meaningful benefit. Data on long-term safety remain limited. Larger, well-designed trials using standardized biomarkers are needed to clarify its therapeutic potential.