A phase 3 trial of Sylentis’ dry eye disease candidate tivanisiran has missed (PDF) its primary endpoints. The PharmaMar subsidiary failed to link the siRNA eye drops to improved scores on scales of ocular pain and corneal staining compared to artificial tears.
Sylentis advanced tivanisiran into phase 3 in the belief that inhibiting the production of ion channels involved in the transmission of ocular pain would improve the lives of people with dry eye disease. To test that idea, investigators enrolled 330 patients and randomized them to receive daily doses of tivanisiran or artificial tears for four weeks.
The Madrid-based biotech emerged from the study with data suggesting tivanisiran is no better than artificial tears at controlling ocular pain or addressing damage to corneal cells. That resulted in the trial missing its primary endpoints.
Sylentis used its release to disclose the news on other, more positive aspects of the data, starting with a statistically significant improvement in central corneal staining, a measure of cell damage. If the performance against the secondary endpoint is reproducible, it would suggest that tivanisiran is effective at improving one part, but not all, of the cornea.
Chief Operating Officer Ana Isabel Jiménez said in a statement that improvements in parts of the cornea have “been recognized by agencies for the approval of other products.” Sylentis plans to discuss the finding and other data points with the FDA and other regulators in the second quarter before deciding on a path forward.
Other results shared by Sylentis include biomarker data that suggest tivanisiran is better than the control in some regards, and findings that show the siRNA improved ocular pain symptoms and corneal staining over baseline. The drug’s inability to perform better than artificial tears in those areas overshadows its performance against baseline, though.
PharmaMar’s stock opened up a bit in Madrid before sliding back toward its starting point as the morning progressed.