P2 CELIA Results Not a Clean Win, but Data Warrants Further Development

Research evidence excerpt

P2 CELIA Results Not a Clean Win, but Data Warrants Further Development

favorable cognitive and functional Risks include commercial, regulatory, clinical,

outcomes compared to external controls. While these findings were based on a small n financing, IP, and execution risks associated with

(n=16), they indicated that the observed tau-lowering effects could translate to clinical marketed and pipeline products.

benefit and prompted advancement to P2.

Price Performance - 1 Year

• P2 CELIA results not a clean win, but data warrants further development. This USD90

morning, IONS and partner BIIB reported topline results from the P2 CELIA study

of diranersen in early AD (n=416). The actual data was not disclosed, and is being 80

presented at AAIC (July 12-15), but BIIB reported that the study did not meet its primary 70

endpoint of a dose-response change from baseline on the Clinical Dementia Rating- 60

Sum of Boxes (CDR-SB) at Week 76. However, pre-specified analyses of cognitive

endpoints showed a slowing of decline across all dose cohorts, most notably in the 50

lowest dose (60 mg Q24W) arm. BIIB also noted that P1b biomarker findings were largely 40

replicated based on robust, sustained reductions in both CSF tau and tau pathology via 30

PET imaging across all doses, along with consistent safety and tolerability. Despite the May-25 Jul-25 Sep-25 Nov-25 Jan-26 Mar-26 May-26

lack of a clear dose-response, BIIB plans to advance this to registration based on the Source: Bloomberg

consistency of the biomarker data and the observed cognitive signals.

• Our take. We don’t think investors had high expectations for this readout, though

think value for the diranersen program may work its way into shares following data

disclosure this summer.