FIGURE 1:

Kaplan–Meier survival curve of the 5 TK2-deficient patients with early onset severe myopathy (onset before 24 months and rapid progression defined by never acquiring ability to walk or loss of ability to walk, to breathe independently, or both within 1 year of onset) showed 100% survival for at least 2 years after treatment (range = 2.1–6.3 years; 3.93 ± 1.66 years, mean ± standard deviation). In contrast, the untreated historical control group with TK2-deficient early onset severe myopathy revealed that only 27.3% of patients survived at least 2 years after onset.^{4–6,9–13,24–30} Shading indicates upper and lower 95% confidence interval. Comparison of treated versus untreated early onset severe myopathy patients demonstrated a significant difference in postonset survival (p = 0.0078).