BACKGROUND

CNS diseases are expected to reach 14.7% of the global disease burden by 2020, making it the largest burden of any disease group. With increasing demand from patients and national health authorities, and the approval of Zolgensma®, development of gene therapies for rare CNS diseases is expected to increase.

OBJECTIVES

To conduct an initial landscape of gene therapy clinical trials (CTs) for rare CNS diseases in order to later understand and anticipate their arrival in market access processes and implications for budget.

METHODS

A systematic review of rare CNS diseases and rare CNS disease gene therapy clinical trials was conducted using the U.S. Department of Health and Human Services, National Center for Advancing Translational Sciences, Genetic and Rare Diseases Information Center, and the U.S. National Library of Medicine Clinical Trials databases.

RESULTS

The systematic review of rare CNS diseases yielded 1274 rare CNS diseases. Of which, 13 were reclassified as not rare and excluded. 609, of the remaining 1261 diseases, were found to have CT information available. Only 33 rare CNS diseases were found to have gene therapy CT information available. These 33 rare CNS diseases had 75 CTs. Of the 75 CTs, 33 were currently recruiting, 18 active and not recruiting, 18 completed, 3 terminated, 1 not yet recruiting, 1 withdrawn, and 1 had an unknown status. In addition 33% were in Phase 1/2, 28% in Phase 1, 8% in Phase 3, 2% in Phase 2/3, and 2% in Phase 2, while 3.4% had “not applicable” phase status.

CONCLUSIONS

Of 1274 CNS disease, less than 3% have gene therapy CT information available. As the majority of gene therapy clinical trials are recruiting and in phase 1/2 for rare CNS diseases, the field merits further investigation to anticipate and address the unique challenges of their impending arrival in current, traditional market access frameworks.