Meridian Genomics has reported 18-month follow-up data from its in vivo gene editing trial for a rare metabolic disorder, showing that the therapeutic effect from a single infusion has remained stable well beyond the window where some earlier gene therapies began to lose efficacy.
The trial enrolled 24 patients with the condition, which causes a buildup of toxic metabolic byproducts due to a single faulty gene. The one-time treatment uses a lipid nanoparticle delivery system to edit liver cells directly, aiming to restore normal enzyme production without the viral vectors used in earlier generations of gene therapy.
At the 18-month mark, 21 of the 24 patients maintained enzyme levels within the target therapeutic range, and reported metabolic crisis events — the condition’s most dangerous complication — dropped by over 90% compared to each patient’s pre-treatment history.
The durability data matters because several prior in vivo editing approaches showed strong initial results that diminished within the first year as edited cell populations turned over. Meridian’s delivery mechanism specifically targets long-lived hepatocytes, which the company believes is the key difference.
A pivotal trial is expected to begin enrollment in the coming months.