By Chris Wack


Ionis Pharmaceuticals Inc. said its partner, Roche Holding AG, has decided to discontinue dosing in its Phase III study of tominersen in manifest Huntington's disease.

The company said the decision was based on the results of a pre-planned review of data from the Phase III study conducted by an unblinded Independent Data Monitoring Committee.

While there were no new or emerging safety signals identified for tominersen, the iDMC made its recommendation based on the investigational therapy's potential benefit/risk profile for study participants. Participants will continue to be followed for safety and clinical outcomes.

Ionis said dosing also will be paused in the open-label extension study of tominersen while data are carefully analyzed to inform next steps on this study. Roche said the Phase I PK/PD study of tominersen and Roche's observational HD Natural History Study will continue.

Roche has stated that once full data from the studies are available and analyzed, it will share learnings and future plans with the community.

Ionis shares were down 21% to $43.86 in premarket trading.


Write to Chris Wack at


(END) Dow Jones Newswires

March 23, 2021 07:00 ET (11:00 GMT)

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