What were the results of the Lp(a)HORIZON trial?

The Lp(a)HORIZON trial results are not in the retrieved evidence. The searches returned studies on a different HORIZON program — the osteoporosis trial of zoledronic acid (HORIZON-PFT) and the heart attack trial HORIZONS-AMI — but nothing on an Lp(a)-lowering therapy.

The closest match is the HORIZON-PFT trial for zoledronic acid in postmenopausal osteoporosis [1]. That trial showed a 70% reduction in new vertebral fractures (3.3% vs 10.9% in placebo) and a 40% reduction in hip fractures (1.4% vs 2.5%) over three years [1]. Bone density improved about 6% at the hip and spine [1]. Serious adverse events were similar between groups (29.2% vs 30.1%), but atrial fibrillation was more common in the zoledronic acid group (50 cases vs 20) [1]. Deaths were 3.4% in the treated group versus 2.9% in placebo [1].

That is a different drug, a different disease, and a different question. The evidence here does not answer what the Lp(a)HORIZON trial found for cardiovascular outcomes with an Lp(a)-lowering agent.

My call: The retrieval missed the Lp(a)HORIZON trial entirely. The question cannot be answered from these records. Confidence: not clear — the evidence does not exist in this search.