Treatment of Idiopathic Pituitary Dwarfism with Methionyl Human Growth Hormone

Transcription

1 Endocrinol. Japon. 1983, 30 (4), Treatment of Idiopathic Pituitary Dwarfism with Methionyl Human Growth Hormone KAZUE TAKANO1, KAZUO SHIZUME1, NAOMI HIZUKA1, ITSURO HIBI2, KIYOHIKO KATO3, HITOSHI KOHNO4, TAKUMA KONDO5, MASAMICHI OGAWA6, YOSHIAKI OKADA7, MASAKATSU SUDO8, SEIZO SUWA9 AND JIRO TAKAHARA10 Department of Medicine, Tokyo Women's Medical College1, Tokyo, National Children's Hospital2, Tokyo, Department of Pediatrics, Yamanashi Medical College3, Yamanashi, Children's Hospital Medical Center4, Fukuoka, Children's Medical Center5, Osaka, Department of Pediatrics, Nagoya University6, Nagoya, Yodogawa Christian's Hospital7, Osaka, Department of Pediatrics, Kyoto University8, Kyoto, Kanagawa Children's Medical Center9, Yokohama and Department of Medicine, Okayama University10, Okayama Abstract Ten patients with idiopathic pituitary dwarfism were treated with methionyl human growth hormone (met-hgh) produced by recombinant DNA technology. They were given 0.5IU/kg/week of met-hgh for three months. There were no significant changes in physical, blood, urine examinations. Their height increased between 1.5 and 2.7 cm during the 3 months of treatment, which was calculated to be equivalent 6.0 and 10.8 cm per year with a mean increase of 8.7cm. Anti-hGH antibody was observed in all patients between one and two months of treatment with a titer between 101 ~and 104 ~. In spite of the formation of antibodies, the growth rate did not decrease in 7 of the 10 cases. Since the success of hgh synthesis by recombinant DNA technology (Goeddel et al., 1979), several investigators have reported the properties and biological activities of methyonyl-hgh (met-hgh) in man and animals (Olson et al., 1981, Hizuka et al., 1982, Rosenfeld et al., 1982a, 1982b, Frigeri et al., 1982, Hintz et al., 1982). We have previously reported biological effects of methgh similar to those of pituitary human growth hormone in eight healthy male volunteers (Takano et al., 1983). In this Received April 25, 1983 paper, we have investigated the growth response and antigenicity of met-hgh in the treatment of patients with idiopathic growth hormone deficiency. This study was performed between October, 1982, and February, Materials and Methods Growth hormone preparations Synthetic methionyl human growth hormone (methgh) (No.82412) was obtained from AB KABI, Stockholm, Sweden. Each vial contained 4 IU hgh (by RIA), 40mg glycine, and 1mg Na-phosphate.

2 524 TAKANO et al. Endocrinol. Japon. August 1983 Table 1. Clinical data from 10 patients with GH deficiency before met-hgh treatment Patients and study design Ten patients aged 6 to 14 years with GH deficiency were investigated. Informed consent was obtained from all patients. Table 1 gives the individual data from clinical findings used in this study. The diagnosis of GH deficiency was established by failure of plasma GH to respond to insulin-induced hypoglycemia, arginine loading, and/or glucagon-propranolol test. Their birth weight was more than 2500g and their height was less than 2.5 standard deviations below normal for the corresponding chronological age. They were all euthyroid and had never been treated with hgh or anabolic steroid before. None was under treatment with hydrocortisone. One of the patients (No.9) was under treatment with DDAVP for diabetes insipidus. Another patient (No.7) was under treatment with thyroxine (100ƒÊg/d), Valproate sodium (INN) (450 mg/d), and Acetazolamide (150mg/d). The aetiology of the disease in these patients was unknown-so called idiopathic growth hormone deficiency. Each patient received 0.5 IU/w/kg of met-hgh in two to four divided doses per week by intramusclar injection for three months. During treatment, vital signs, height, and body weight were checked by the same physician. Blood count, urinalysis, routine chemistries, and measurement of thyroid hormones and antibody against met-hgh were performed before, and 2 weeks, one, two, and three months after treatment with methgh. Assay methods Antibody against hgh was estimated by a radioimmunoassay using serum obtained from patients. Incubation was performed with 50 ƒêl 125I-hGH, 50 ƒêl serum sample, 100 ƒêl 1% ƒá-globulin, and with or without 50 ƒêl of unlabelled hgh (1ƒÊg/ml) in a total volume of 500 ƒêl veronal buffer. Separation of bound and free hormone was performed using 500 ƒêl of 25% polyethylene glycol (Besbuquois & Aurbach, 1971). Serum was diluted in a ten fold series and the titer of the antibody was expressed as the final dilution of the plasma which gave the optimal binding above control. Control binding was obtained utilizing 1% bovine ƒá-globulin. As the labelled and unlabelled hgh, NIH hgh (hgh-afp-4793b) was used. Routine chemistries and blood count were measured by standard automated techniques. Serum T3 and T4 were measured with a commercial RIA kit. Statistical analysis Student's t-test and paired t-test were used for statistical analysis. Results The growth rate and titer of anti-hgh antibody during treatment are shown in Table 2. During the 3 months of treatment, height increased between 1.5 and 2.7 cm, which calculates out to between 6.0 and 10.8 cm per year. There was no relationship between the growth on the one hand and bone age, height age, or the ratio of bone age and chronological age on the other. The determination of the titer of antibody to hgh is shown in Figure 1. This is an example from some serum samples obtained 2 months after met-hgh treatment. The 125I-hGH bound serum sample was displaced by 100 ng/ml unlabelled hgh at a suitable dilution of serum. The titer of antibody in cases 4, 5, 6, 7 and 8 was determined to be 104 ~; in case 9, 103 ~; in case 3, 102 ~; and in case 1, 101 ~. There was no antibody after 2 weeks of treatment. However, in 6

3 Vol.30, No.4 TREATMENT OF PITUITARY DWARF WITH MET-hGH 525 Table 2. Growth rate and titer of anti-hgh antibody during the treatment with met-hgh n.t.=not tested Fig. 1. The percent binding of 125I-hGH to varying dilutions of sera from patients with met-hgh treatment for 2 months. Numbers in the figure indicate the same subjects as in Table 1. cases out of 8, the antibody appeared one month after the start of treatment. The titers of hgh antibody varied between 101 ~ and 103 ~. After 2 months of treatment, the and-hgh antibody was observed in all Table 3. The changes in blood count, blood chemistry and other values before and 3 months after met-hgh treatment (Mean }SEM) patients. The titer of the antibody increased 10 to 100 times during one month; however it did not increase further in most cases after 3 months of treatment. Before and during treatment with methgh no special changes in blood count, urinalysis, or routine chemistries were noted by paired t-test (Table 3). There were neither pyrogenic effects nor other side effects.

4 526 TAKANO et al. Endocrinol. Japon. August 1983 Discussion We investigated the effect of methionyl hgh on growth in patients with pituitary dwarfism and observed excellent growth response in all patients. Their height increased between 1.5 and 2.7cm during 3 months of treatment, which corresponded to between 6 and 10.8cm per year. There are huge amounts of records on the treatment of pituitary dwarfism with pituitary-hgh. About fifteen hundred patients with growth hormone deficiency have been treated with pituitary growth hormone in Japan and there is a remarkable height increase of between 5 and 12 cm in the first year of treatment. The effect of met-hgh on growth was comparable to that of pituitary-hgh. A remarkable difference between methgh and pituitary hgh was the antigenicity. There were many reports on the antigenicity of pituitary-hgh (Underwood et al., 1974, Fraiser et al., 1974, Kaplan et al., 1974). They reported that about 40% of the patients developed detectable antibodies during the treatment period. Kaplan et al., (1974) reported that 38 out of 98 patients treated with GH by Drs. Wilhelmi, Raben and/or Saxena had anti-hgh antibodies and that antibodies were detectable by 3 months after the onset of therapy in 3, by 6 months in 9, and thereafter in the rest of the patients. The main cause of the antigenicity was the polymeric hgh produced during the purification processes. After the improvement of purification and use of frozen pituitary gland, pituitary-hgh became less antigenic. During treatment with KABI's hgh (Crescormone(R)), only one out of twenty patients developed antibodies to hgh in serum (Hall and Olin 1972). Shizume et al. (1974) also reported that Crescormone (KABI-hGH) was less antigenic. We detected antibodies in only four out of 48 patients treated with pituitary hgh for more than six months. Even when antibodies were produced, their titers were low and did not interfere with the effect of hgh in any of the cases. After treatment with met-hgh, antibodies were produced in all patients after 2 months. In spite of the formation of anti-hgh antibody, growth rate increased between the 2 nd and 3 rd month of treatment in 4 cases (Nos. 1, 3, 5 and 7), it decreased in 3 cases (Nos. 2, 8 and 10) and did not change in 3 cases (Nos. 4, 6 and 9). High titers of anti-hgh antibody might attenuate the growth effects of hgh. However, more long-term treatment will be required to examine this possiblility. There were no denatured forms of hgh in these preparations (personal communication from Kabi); however very minute amounts of E. coli protein were presented. This antigenicity might be due to a conjugated form of met-hgh with this protein. Thus, a more purified hgh might produce antibodies much less frequently. The possibility that the methionine residue could be responsible for the production of antibodies is not completely denied at present. Acknowledgements The authors are very grateful to Sumitomo Pharmaceutical Co., Ltd. (Osaka, Japan) for supplying methionyl hgh preparations and performing statistical analysis. This report was partly supported by Grants in Aid for Scientific Research, Ministry of Education, Science and Culture, Japan (No , No and ), by a Research Grant from the Intractable Disease Division, Public Health Bureau, Ministry of Health and Welfare, and a research grant from the Foundation for Growth Science in Japan. References Besbuquois, B. and G. D. Aurbach (1971). Use of Polyethylene glycol to separate free and antibodybound peptide hormones in radioimmunossay. J. Clin. Endocrinol. Metab. 33, Frasier, S. D., T. Aceto, Jr., A. B. Hayles, M. L.

5 Vol.30, No.4 TREATMENT OF PITUITARY DWARF WITH MET-hGH 527 Parker and H. F. L. Meyer-Bahlburg (1974). Collaborative study of the effects of human growth hormone in growth hormone deficiency. II. Development and significance of antibodies to human growth hormone during the first year of therapy. J. Clin. Endocrinol. 38, Frigeri, L. G., G. Robel and N. Stebbing (1982). Bacteria-derived human growth hormone lacks lipolytic activity in rat adipose tissue. Biochem. Biophys. Res. Commun. 104, Goeddel, D. V., H. L. Heyreker, T. Hozumi, R. Arentzen, K. Itakura, D.G. Yansura, M.J. Ross, G. Miozzari, R. Crea and P. H. Seeburg (1979). Direct expression in E. coli of a DNA sequence coding for human growth hormone. Nature 281, Hall, K. and P. Olin (1972). Sulphation factor activity and growth rate during long-term treatment of patients with pituitary dwarfism with human growth hormone. Acta Endocrinol. (Kbh) 69, Hintz, R. L., R. G. Rosenfeld, D. M. Wilson, A. Bennett, J. Finno, B. McClellan and R. Swift (1982). Biosynthetic methionyl human growth hormone is biologically active in adult man. Lancet I, Hizuka, N., C.M. Hendricks, G.N. Pavlakis, D.H. Hamer and P. Gorden (1982). Properties of human growth hormone polypeptides purified from pituitary extracts and synthesized in monkey kidney cells and bacteria. J. Clin. Endocrinol. Metab. 55, Kaplan, S.L., D.C.L. Savage, S. Suter, R. Wolter and M.M. Grumbach (1974). In: Proc. Advanc. Human Growth Hormone Research Symposium, Baltimore DHEW Publication No. (NIH) , Olson, K.C., J. Fenno, N. Lin, R.N. Harkins, C. Snider, W. H. Kohr, M. J. Ross, D. Fodge, G. Prender and N. Stebbing (1981). Purified human growth hormone from E. coli is biologically active. Nature 293, Rosenfeld, R. G., B. B. Aggarwal, R. L. Hintz and L. A. Dollar (1982a). Recombinant DNA-derived methionyl human growth hormone is similar in membrane binding properties to human pituitary growth hormone. Biochem. Biophys. Res. Commun. 106, Rosenfeld, R. G., D. M. Wilson, L. A. Dollar, A. Bennett and R. L. Hintz (1982b). Both human pituitary growth hormone and recombinant DNAdrived human growth hormone cause insulin resistance at a postreceptor site. J. Clin. Endocrinol. Metab. 54, Shizume, K., R. Demura, K. Ichikawa, K. Takano, E. Odagiri, T. Maeda, T. Suda and H. Demura (1974). Treatment of idiopathic pituitary dwarfism with human growth hormone (KABI). Endocrinol. Japon. 21, Takano, K., N. Hizuka, K. Asakawa, M. Kogawa and K. Shizume (1983). Short-term study of biosynthesized hgh in man. Endocrinol. Japon. 30, Underwood, L. E., S. J. Voina and J. J. Van Wyk (1974). Restoration of growth by human growth hormone (Roos) in hypopituitary dwarfs immunized by other human growth hormone preparations: clinical and immunological studies. J. Clin. Endocrinol. 38,