Figure 1.

Survival and clinical progression of post-symptomatic AAV-treated SD cats and untreated SD cats. (a) Age of symptom onset is shown for untreated SD cats (mean ± s.d, n = 14). The scale is based on gait defects, which ultimately define humane endpoint, with initial deficits at 2.1 months old. However, disease onset begins at 1.3 months old with subtle tremors of the head/tail that progress to overt whole-body tremors at 2.4 months old. Neurologic humane endpoint is reached at a score of 3. (b) Kaplan-Meier survival curves for untreated SD cats (solid black line, n = 14) and SD cats treated post-symptomatically. Survival of the EPS cohort is significantly increased compared to untreated (P = 0.0010, dashed black line, n = 4) and compared to the LPS cohort (P = 0.048). Survival of the LPS cohort is not significantly increased compared to untreated (P < 0.28, solid grey line, n = 3). Normal controls (not shown) remained alive and healthy throughout the study. (c, d) Composite clinical scores are shown for untreated SD cats (n = 14) while EPS (c) and LPS (d) treated cats are depicted separately. Open symbols denote the presence of subtle tremors, and checkered symbols denote the presence of overt whole body tremors, which were absent in all EPS treated cats, but present in all LPS treated cats. Scores were assigned using two separate, independent readouts, as described in materials and methods. Normal controls (not shown) scored a 10 on the clinical rating scale and had no tremors for the duration of the study.