WinRho-SD (anti-D) was recently licensed for the treatment of ITP. We report the results of anti-D therapy of 104 non-splenectomized, HIV negative children with acute (n=43) and chronic (n=61) ITP, treated at NY Hospital from 1987 to 1994. The mean platelet increase (plt incr) following the first infusion for all 104 pts was 120 × 103/ul (120k) with a median of 82k; the overall response rate (% of pts with plt incr >20k) was 83%. None of 4 variables (pre-treatment plt ct, duration of ITP, dose of anti-D, and gender) had any effect on response. There was a mean plt incr of 117k when the pre-treatment plt ct was < 20k and 123k for ≥ 20k. Pts with chronic and acute ITP responded equally well. The anti-D dose had no effect on the plt incr: 1) 20-30 ug/kg,n=17, mean plt incr 106k; 2) 30-40 ug/kg,n=23,125k; and 3) 40-60 ug/kg, n=35, 109k. The duration of effect was >14 days in 73% of responders. Table 35 pts received 3 consecutive infusions and the response rates were 100%, 89% and 80% respectively. 7 responding pts received > 10 anti-D infusions as maintenance therapy with a response rate of 94%. The mean hemoglobin decrease was 0.9 gm/dl. No variable had a significant effect on hemolysis. Anti-D is an efficacious and safe therapy for children with ITP. Its ease of administration and lack of tachyphylaxis make IV anti-D optimal for maintenance.
