Clinical Experience with Genotropin in Growth Hormone Deficient Children

Abstract

The efficacy of Genotropin (recombinant somatropin, KabiVitrum AB, Sweden) was analysed in 194 children with GH deficiency, comprising a combined series of four multicentre trials. The linear height velocity increased from 3.3±1.4 to 9.3±2.6 cm/year in 149 prepubertal children with 12 months’data available. In 18 pubertal children the pretreatment height velocity was 4.0±1.2, and increased to 8.4±1.7 cm/year during 12 months of treatment. There was a positive correlation between the gain in height velocity and the weekly dose of Genotropin. Covariance analysis revealed significantly greater height velocity with 6‐7 injections/week compared to 2‐3 injections/week; corrections for chronological age, bone age, height SD score and dose were made. On average, a regimen of 6‐7 injections/week was 25% more effective than one of 2‐3 injections/week corresponding to an extra gain in height velocity of 1.8±0.6 cm/year. At 12 months, only 0.9% of the children had developed anti‐GH antibodies. Very few side‐effects have been reported from more than 1000 children on Genotropin.

Evaluation of Biosimilarity Based on an Empirical Bayes Method

“…Details are listed in Table 2. We use the result in the paper of Wilton and Gunnarsson [17] and that in the paper of Romer et al [18] to illustrate the empirical Bayes method for assessing biosimilarity.…”

“…According to the paper of Wilton and Gunnarsson [17], the average height velocity, in 149 prepubertal children with GHD, increased from 3.3 to 9.3 cm/yr. Genotropin is widely used as a replacement therapy of hGH for children with GHD or Prader-Willi syndrome (PWS).…”

“…The result from Wilton and Gunnarsson [17] is regarded as the historical information of the innovator drug, Gneotrope. Therefore, we knew that (   For assessing high similarity, the limit for allowing the similarity is selected as ρ = 0.9.…”