Novartis (NYSE: NVS) announced Friday September 4, 2026 that the pelacarsen Phase 3 Lp(a)HORIZON trial did not meet its primary endpoint of reducing major adverse cardiovascular events (a composite of cardiovascular death, non-fatal myocardial infarction, non-fatal stroke, and urgent coronary revascularization requiring hospitalization) versus placebo in patients with elevated lipoprotein(a) plus established cardiovascular disease on guideline-directed background therapy including lipid-lowering and antihypertensive medications. Pelacarsen (an antisense oligonucleotide targeting hepatic APO(a) production, licensed from Ionis Pharmaceuticals in 2019) did achieve substantial lower Lp(a) levels versus placebo. The trial enrolled roughly 8,000 patients globally over 6 years and represents the largest and most consequential test to date of the Lp(a)-as-causal-cardiovascular-risk-factor hypothesis. The miss substantially raises the bar for Amgen's olpasiran (RNAi, Phase 3 OCEAN(a) ongoing), Silence Therapeutics's zerlasiran (RNAi), and Lilly's lepodisiran (RNAi) — all of which are testing similar Lp(a)-lowering-plus-cardiovascular-outcome frameworks. Ionis and Royalty Pharma both hold economic interests in pelacarsen.
AstraZeneca (NASDAQ: AZN) and Ionis Pharmaceuticals (NASDAQ: IONS) presented Sunday August 30, 2026 at ESC Congress 2026 Munich the detailed subgroup analyses from the Phase 3 CARDIO-TTRansform trial of Wainua (eplontersen, an antisense oligonucleotide targeting transthyretin) in adults with transthyretin-mediated amyloid cardiomyopathy (ATTR-CM). CARDIO-TTRansform did not meet its primary composite endpoint (cardiovascular mortality plus recurrent CV events through 140 weeks) versus placebo. In the prespecified subgroup analysis, patients receiving eplontersen monotherapy achieved a nominally significant hazard ratio of 0.71 versus placebo, while patients on background TTR stabilizer therapy (tafamidis, Vyndaqel/Vyndamax) at baseline showed no treatment effect. The read-out complicates the silencer-plus-stabilizer commercial approach in ATTR-CM that Alnylam's HELIOS-B trial of vutrisiran validated with 28.2% mortality reduction and 32.8% CV event reduction on background tafamidis. AstraZeneca and Ionis will analyze the full dataset to inform next steps in the CARDIO-TTRansform program.
Biogen (NASDAQ: BIIB) presented full Phase 2 CELIA study data for diranersen (BIIB080), an investigational tau-targeting antisense oligonucleotide (ASO) delivered intrathecally, at AAIC 2026 in London on Tuesday July 14, 2026 during the Developing Topics in Phase 2 Clinical Trials Session (2:00-3:30 PM BST). The 76-week placebo-controlled study evaluated three doses (60 mg every 24 weeks, 115 mg every 24 weeks, and 115 mg every 12 weeks) and did not meet its primary endpoint of dose response on the Clinical Dementia Rating-Sum of Boxes (CDR-SB) at Week 76. Strong reductions in tau pathology occurred across all studied doses, generally consistent with the Phase 1b study. Prespecified analyses of cognitive endpoints demonstrated slowing of clinical decline across all doses, with the effect particularly pronounced at the lowest 60 mg q24w dose. Biogen framed the results as the first randomized Phase 2 evidence of a tau-directed therapy showing both biomarker impact and cognitive benefit, and plans to advance diranersen to registrational Phase 3 development.