<br>        Main Study Inclusion Criteria:<br><br>          1. Pre-pubertal children aged =3 years , and not yet 11 years for girls or not yet 12<br>             years with either isolated GHD, or GH insufficiency as part of multiple pituitary<br>             hormone deficiency.<br><br>          2. Confirmed diagnosis of GHD by two different GH provocation tests defined as a peak<br>             plasma GH level of =10 ng/mL,<br><br>          3. Bone age (BA) is not older than chronological age and should be less than 10 for girls<br>             and less than 11 for boys.<br><br>          4. Without prior exposure to any r-hGH therapy (naïve patients).<br><br>          5. Impaired height and height velocity defined as:<br><br>               -  Annualized height velocity (HV) below the 25th percentile for CA (HV < -0.7 SDS)<br>                  and gender according to sponsor calculator using Tanner, Prader, and Hermanussen<br><br>               -  The interval between 2 height measurements should be at least 6 months, but<br>                  should not exceed 18 months prior to inclusion<br><br>          6. Baseline IGF-I level of at least 1 SD below the mean IGF-1 level standardized for age<br>             and sex (IGF-1 SDS =-1)<br><br>          7. Normal calculated GFR per updated bedside Schwartz formula<br><br>          8. Children with multiple hormonal deficiencies must be on stable replacement therapies<br>             (no change in dose) for other hypothalamo-pituitary-organ axes for at least 3 months<br>             prior ICF signing<br><br>          9. Normal 46XX karyotype for girls.<br><br>         10. Provide consent/assent<br><br>             LT-OLE Inclusion Criteria:<br><br>         11. Completion of the main study (12 months of treatment) with adequate compliance.<br><br>         12. Provide consent/assent<br><br>         13. Agree to refrain from sexual activity<br><br>        Main Study Exclusion Criteria:<br><br>          1. Children with prior history of leukemia, lymphoma, sarcoma or any other forms of<br>             cancer.<br><br>          2. History of radiation therapy or chemotherapy<br><br>          3. Malnourished children defined as BMI < -2 SDS for age and sex<br><br>          4. Children with psychosocial dwarfism<br><br>          5. Children born small for gestational age (SGA - birth weight and/or birth length <-2<br>             SDS for gestational age)<br><br>          6. Presence of anti-hGH antibodies at screening<br><br>          7. Any clinically significant abnormality likely to affect growth or the ability to<br>             evaluate growth, such as, but not limited to, chronic diseases like renal<br>             insufficiency, spinal cord irradiation, etc.<br><br>          8. T2 and T1 diabetic patients, who in the opinion of the investigator are not receiving<br>             standard of care treatment or are non-compliant with their prescribed treatment or who<br>             are in poor metabolic control.<br><br>          9. Chromosomal abnormalities including Turner's syndrome, Laron syndrome, Noonan<br>             syndrome, Prader-Willi syndrome, Russell-Silver syndrome, SHOX mutations/deletions and<br>             skeletal dysplasias.<br><br>         10. Concomitant administration of other treatments that may have an effect on growth such<br>             as anabolic steroids, or sex steroids, with the exception of ADHD drugs or HRT<br>             (thyroxin, hydrocortisone, desmopressin)<br><br>         11. Children requiring glucocorticoid therapy (e.g. for asthma) that are taking<br>             chronically a dose greater than 400 µg/d of inhaled budesonide or equivalent<br><br>         12. Major medical conditions and/or presence of contraindication to r-hGH treatment.<br><br>         13. More than one closed epiphyses<br><br>         14. Known or suspected HIV-positive patient, or patient with advanced diseases such as<br>             AIDS or tuberculosis.<br><br>         15. Drug, substance, or alcohol abuse.<br><br>         16. Known hypersensitivity to the components of study medication.<br><br>         17. Other causes of short stature such as celiac disease, uncontrolled primary<br>             hypothyroidism and rickets.<br><br>         18. Possible non-compliance in respect to study conduct<br><br>         19. Participation in any other trial of an investigational agent within 30 days prior to<br>             consent<br><br>         20. Study enrollment has been met or study is closed by sponsor prior to completion of<br>             screening process.<br><br>             LT-OLE Exclusion Criteria:<br><br>         21. Concomitant administration of other treatments that may have an effect on growth such<br>             as anabolic steroids, or sex steroids, with the exception of ADHD drugs or HRT<br>             (thyroxin, hydrocortisone, desmopressin)<br><br>         22. Change in medical condition during the treatment period (such as, but not limited to,<br>             development of a serious inter-current critical illness, a severe adverse drug<br>             reaction, etc.)<br><br>         23. Positive pregnancy test<br><br>         24. Unresolved drug related (Genotropin or MOD-4023) SAE from the treatment period as per<br>             medical monitor judgement.<br>