Efficacy and Safety Evaluation of Recombinant Human Growth Hormone (r-hGH), Saizen®, on a Population of Children With Hypochondroplasia, Treated at Least 3 Years or Until Near Final Height, When Applicable, in Comparison With a Historic Cohort of Non-treated Children

Inclusion Criteria

• Male or female children with hypochondroplasia defined by a disproportional short limb height and a X-ray evidence of shortening of the long bones and failure of increase in the interpedicular distance between lumbar vertebrae L1 and L5
• Result of genetic analysis for mutation of gene FGFR3 already known or ongoing analysis at the beginning of the study
• Chronological age greater than or equal to 3 years
• Height for chronological age less than or equal to - 2 SDS
• Bone age less than or equal to 11 years for girls and 13 years for boys
• A written informed consent at the beginning of the pre-treatment period must be obtained from the parent(s)/legal guardian(s). Children able to understand the trial should personally sign and date the written informed consent

Additional inclusion criteria for each study prolongation:

• Bone age at Month 36 or Month 60 is compatible with treatment prolongation according to investigator opinion
• Subject is still under r-hGH treatment with Saizen® at Month 36 or Month 60
• Height gain greater than or equal to + 1 SDS after the 2 first years of treatment for treatment prolongation at Month 36 and growth velocity greater than or equal to 5 centimeter (cm) per year, with bone age less than 14 years for females or less than 16 years for males for treatment prolongation at Month 60
• According to investigator opinion, gene mutations of the subjects are not in connection with observed side effects during the 3 or 5 first years of treatment
• An updated written informed consent must be obtained from the parent(s)/legal guardian(s) before the start of each study prolongation. Children able to understand the trial should personally sign and date the written informed consent

Exclusion Criteria

• Turner's Syndrome in girls
• Active malignant neoplastic disease
• Severe congenital malformations
• Proliferative or preproliferative diabetic retinopathy
• Evidence of any progression or recurrence of an underlying intra-cranial space occupying lesion
• Severe psychomotor retardation
• Diabetes mellitus or history of significant glucose intolerance as defined by a fasting blood glucose greater than 6.4 millimole per liter (mmol/L)
• Known renal insufficiency as defined by serum creatinine level 1.0 milligram per deciliter (mg/dL) (88 micromole per liter [mcmol/L])
• Known hepatic disease as defined by elevated liver enzymes or total bilirubin (* 2 Normal)
• Current congestive heart failure, untreated hypertension, serious chronic edema of any cause
• Chronic infectious disease
• History of intracranial hypertension with papilledema
• Previous or ongoing treatment with sex steroid therapy such as estrogens or testosterone
• Previous or ongoing treatment with any therapy that may directly influence growth, including Growth Hormone (GH), Growth Hormone Releasing Hormone (GHRH) and long duration corticosteroids therapy
• Known hypersensitivity to somatropin or any of the excipients
• Epiphyseal fusion
• Participation to any clinical study within the 30 days preceding study entry
• Pregnant females