Thinly traded AVROBIO (AVRO +7.9%) is up on increased volume in early trade following its announcement of additional positive data and the first kidney biopsy results from its two ongoing clinical trials evaluating gene therapy candidate AVR-RD-01 in patients with an inherited disorder called Fabry disease, characterized by the buildup of a type of fat (globotriaosylceramide or Gb3) in the body’s cells.
Eight patients have been dosed to date, five in the Phase 1 FACTs study and three in Phase 2 FAB-201.
The primary endpoint in FAB-201 is the change from baseline in the average number of Gb3 inclusions per peritubular capillary as measured in a kidney biopsy one year post-treatment.
The first treated patient in FAB-201 showed an 87% reduction in Gb3 substrate in the kidney and an 87% reduction in plasma lyso-Gb3 at year one (data on the other two not provided). The first four in the Phase 1 study experienced plasma lyso-Gb3 reductions of 33 – 41% from baseline (data on the fifth not provided).
The treatment effect was sustained across multiple parameters. Kidney and cardiac functions were stable and in the normal range in the first Phase 2 patient at one year.
No new safety signals were observed.
