The treatment of precocious puberty with cyproterone acetate

Experience with cyproterone acetate in the treatment of precocious puberty

The authors review their experience (1967-present) in the use of cyproterone acetate (CPA) in precocious puberty. CPA was found effective in persistently suppressing pituitary gonadotropic secretion when administered orally at a dose of 50 mg b.i.d. (70-100 mg/d). After the introduction of gonadotropic analogues (GnRHa) for treatment of central precocious puberty, short term use of CPA was found useful to counteract the initial stimulatory effect of the GnRHa as well as an adjunct drug in case of very active adrenarche causing advanced bone age during GnRHa treatment. The final heights of girls treated with CPA and girls treated with D-Trp6-LHRH were found comparable: 157.8+/-5.1 cm vs 159.6+/-6.3 cm, respectively. The main adverse effects were occasional fatigue due to partial adrenal insufficiency with CPA and gynecomastia in a few boys. Liver function tests were normal in all patients with the exception of one boy with severe hypothalamic disease, including precocious puberty, who developed liver cirrhosis 3 years after stopping CPA following 5 years treatment. Other indications for CPA treatment during childhood and adolescence, such as fast puberty, congenital adrenal hyperplasia and acne, are also mentioned.

The effect of cyproterone acetate on the growth of children with central precocious puberty

We have examined the growth and skeletal maturation of 19 children (6 male, 13 female) with central precocious puberty. The aetiology in nine patients (5 male, 4 female) was secondary to a hypothalamic hamartoma. Six children (2 male, 4 female) received no treatment whereas 13 children (4 male, 9 female) were treated with cyproterone acetate in a mean dose of 68 mg/m2 per day (range, 34-260) for a mean duration of 4.5 years (range, 0.8-7.9). There was no significant difference between height SDS for bone age at the beginning and end of observation in either treated or untreated groups. No significant relationship between the mean dose of cyproterone acetate used and change in height SDS for bone age could be determined. We conclude that cyproterone acetate has no beneficial effect on the growth prognosis of children with central precocious puberty.

Clinical and endocrinologic study of precocious puberty in girls

We describe 30 girls with precocious puberty whom we have seen during the last ten years. Modern procedures such as cerebral computer tomography and abdominal sonography increase diagnostic accuracy so that the incidence of idiopathic precocious puberty is likely to diminish. Abdominal sonography is of value in detecting and monitoring the growth of ovarian cysts and thus exploratory laparotomy can be avoided in those cases in which cysts regress rapidly. A modified classification of precocious is proposed.

3H-cyproterone acetate: binding characteristics to human uterine progestagen receptors

The availability of tritium labeled cyproterone acetate (CPA) facilitated the systematic investigation of the binding characteristics of this compound for human uterine progesterone receptors (PgR). The binding parameters of 3H-CPA are compared to those of 3H-R5020 and 3H-progesterone. The rate constants of association (k1M-1sec-1) to PgR were 7.8 X 10(3) for 3H-R5020, 4.5 X 10(4) for 3H-progesterone and 4.0 X 10(4) for 3H-CPA. The rate constants of dissociation (k-1, sec-1) were 3.6 X 10(-5) for 3H-R5020, 21.3 X 10(-5) for 3H-progesterone and 17.8 X 10(-5) for 3H-CPA. The Kd-values (M), as obtained by titration analysis and subsequent Scatchard plot analysis were 1.2 X 10(-9) for 3H-R5020, 6.0 X 10(-9) for 3H-progesterone and 5.2 X 10(-9) for 3H-CPA. On sucrose density gradient analysis binding in the 3.5, 5 and 8 S area could be observed using 3H-R5020. For 3H-progesterone and 3H-CPA binding was exclusively found in the 5 S area. The specificity of the steroid binding site of PgR is identical for 3H-R5020 and 3H-CPA. The order of potency of binding for various competitors decreases identically for both radioactive ligands: R5020 less than progesterone less than R1881 less than CPA less than dihydrotestosterone less than dexamethasone less than cyproterone less than 15 beta-OH-cyproterone. CPA resembles progesterone very closely in its binding characteristics to human uterine PgR.

Treatment of precocious puberty with LHRH analogue in combination with cyproterone acetate-further experience

Six girls and one boy with precocious puberty were treated with a superactive LHRH analogue (D-TRP6-LHRH) for periods ranging from 1 year to 2 years and 3 months. In the first phase of the treatment it was administered in combination with cyproterone acetate (CyA) to counteract an early stimulatory effect until inhibition of gonadotrophin secretion was achieved. The gonadotrophin-dependent signs i.e. gonadarche, showed sustained arrest and even regression. Gonadal sex steroids decreased but the adrenal androgens were unaffected. In four patients who showed progression of the angrogen-dependent signs (adrenarche), despite suppression of gonadotrophins, increasing the dosage of the LHRH analogue was ineffective and combined therapy with CyA was reinstituted in three of them because of accelerated growth and bone maturation. It is concluded that at present the treatment of choice for precocious puberty is the daily administration of a superactive LHRH analogue such as D-TRP6-LHRH, together with CyA in the initial stage, and at a later state if adrenarche progresses too rapidly.

Pubertal development: normal, precocious and delayed

The present concepts on the neuroendocrine mechanisms which trigger pubertal development and modulate the progression towards sexual maturity have been reviewed. Essentially, puberty is presented as a continuum, the programming of which is initiated prenatally and which ends in adult life when all hormonal secretions become autoregulated. This continuum is dependent on a delicate equilibrium between CNS neurohormones (GnRH), neurotransmitters (biogenic amines), pituitary gonadotrophin (FSH, LH) secretion and the end-organ response (testis or ovary) through the activation of specific membrane receptors. The gonadal sex steroids (T, OE2) will activate specific cytoplasmic and nuclear receptors of target tissues and exert their biological action. Initially, the activity of the HPGA is manifested by nocturnal LH peaks, followed by increased gonadal secretion of T or OE2. Extremely sensitive to negative feedback by circulating androgen and/or oestrogen in prepuberty, an hypothalamic regulatory system called the gonadostat increases its threshold of sensitivity and eventually becomes autoregulated at a higher feedback level. Progressively, the hypothalamus becomes sensitive to positive feedback action of gonadal hormones, this phenomenon being important for the onset of ovulation. It is likely also that adrenal androgens play a permissive and supportive role in the onset and progression of pubertal development. Finally, full maturity is reached, with final adult height through fusion of the epiphysis, and fertility is achieved. The clinical manifestations of each developmental stage of puberty are described and abnormalities of sexual development reviewed. While over 90 per cent of cases of precocious pubertal development are idiopathic in girls, a space-occupying lesion in the hypothalamic-pituitary region is frequent in boys. Dissociated pubertal signs (premature adrenarche, pubarche, thelarche, menarche) are discussed, together with diagnosis and treatment of precocious puberty, whether it is idiopathic or occurring independently of the activation of the HPGA. In addition to delay of puberty on a constitutional basis, or related to chronic endocrine or non-endocrine diseases, the main clinical entities with gonadal insufficiency, primary (hypergonadotrophic) or secondary (hypogonadotrophic), are reviewed in boys and girls and their investigation and treatment discussed.

Cyproterone acetate treatment in precocious puberty

Seven girls with precocious puberty, idiopathic in 6 and associated with the McCune Albright syndrome in 1, were treated with 70 mg/M2/die of cyproterone acetate (CPA) for 11 to 36 months. Before and during treatment clinical parameters (weight, height, bone age, height velocity, prediction of adult height and pubertal development) were evaluated and plasma hormone assays in basal conditions (LH, FSH, 17 beta-estradiol, progesterone, testosterone, PRL, ACTH and cortisol) and after stimulation (LH, FSH, cortisol, GH) were carried out to assess the efficacy and eventual side effects of CPA. The regression observed in the clinical signs of puberty was considered satisfactory and the increase observed in the developmental quotient indicated an improved prognosis for adult height. No symptoms of adrenal insufficiency were observed but an adrenal suppressive effect of CPA was evident from the response to insulin hypoglycemia observed in 4 patients.

Effect of cyproterone acetate on adrenocortical function in children with precocious puberty

Seven children with precocious puberty were treated with cyproterone acetate and their adrenal function studied. In each child the drug caused significant adrenal hypofunction which was secondary to adrenocorticotrophic hormone suppression. None of these children had clinical evidence of adrenal hypofunction and it is assumed that the drug has glucocorticoid-like properties. Children receiving cyproterone acetate should carry information to warn doctors of this effect since they may require steroid cover during illness.

Endocrine effects of cyproterone acetate in patients with prostatic cancer

Cyproterone acetate was given to patients with stages C and D prostatic cancer and its effect on endocrine parameters was studied. At a daily oral dose of 100 mg. cyproterone acetate induced marked reduction in the size and consistency of tumor, while it caused moderate suppression of serum luteinizing hormone, follicle-stimulating hormone and testosterone levels. Elevation of serum prolactin levels was observed after treatment with cyproterone acetate but was to a lesser degree than that caused by estrogens.

Effect of cyproterone acetate (CA) on growth and endocrine function in precocious puberty

16 girls with precocious puberty have been studied. Following low dosage cyproterone acetate (CA) therapy (mean daily dosage 65 mg/m2BSA) a beneficial effect on growth and skeletal maturation was observed. During high dosage therapy (150 mg/m2 per day) endocrinological studies were performed in 10 of these patients. There was no significant difference in HGH levels (insulin- and arginine-test), T3 and TSH values (TRH-test) between patients and controls, T4 concentration was significantly increased. Basal prolactin levels and prolactin response to TRH was definitely elevated. Oral glucose load and arginine infusion resulted in a significantly enhanced insulin release. There was a significant reduction in basal LH levels and an increase in FSH response to LH-RH. Basal and diurnal plasma cortisol values were markedly reduced and the cortisol release due to corticotrophin injection, lysinevasopressin (LVP) injection and insulin-hypoglycemia as well. A definite increase in basal ACTH levels was observed, during LVP- and insulin-hypoglycemia test ACTH concentrations were within or significantly above normal range. In our patients a primary adrenocortical insufficiency due to CA treatment was evident.

The LH and FSH responses to LH-releasing hormone (LH-RH) in girls with true precocious puberty treated with cyproterone acetate

Ten girls with precocious puberty ranging in age from 7 to 10 7/12 years who were treated with oral cyproterone acetate on a long term basis, were subjected to LH-RH tests, prior to and 3 to 16 months after the institution of therapy. Cyproterone acetate was given in doses from 60 to 153 mg/m2, which proved to be clinically effective, as evidenced by the slowing down of sexual maturation. The basal levels of LH were found to be unaffected by therapy and corresponded to the pubertal stages of the individual girls. The peak increment of LH after LH-RH stimulation was markedly suppressed by the therapy. FSH secretion and its responsiveness to LH-RH was not affected by cyprotereone acetate. The basal levels of FSH were higher during therapy than before, but the peak FSH increment remained the same. An escape phenomenon in the LH peak response was evident in 2 patients upon retesting after prolonged therapy. It is possible that the antigonadotrophic action of cyproterone acetate is due to its progestational nature.

Cyproterone acetate in treatment of precocious puberty

Twenty-nine children (23 girls, 6 boys) with precocious puberty were treated with cyproterone acetate for various periods of time ranging from 6 months to 3 years 4 months. They received an oral dose ranging from 70-150 mg/m2 per day, or an intramuscular depot injection once a fortnight or once a month at a dose ranging from 107-230 mg/m2. Both forms of therapy were found to suppress the signs of sexual maturation, but the oral form proved to be superior. Only the younger patients with a bone age under 11 years showed a beneficial effect upon linear growth and bone maturation. No side effects were noted, but additional advantageous effects upon behaviour and sociability were. It is concluded that at present cyproterone acetate by mouth is the drug of choice in the treatment of precocious puberty. The treatment should be initiated as early as possible to attain maximum benefit.

The LH response to LH releasing hormone in children with true isosexual precocious puberty treated with cyproterone acetate

Fourteen girls and one boy with isosexual precocious puberty were submitted to LHRH stimulation tests, during and without therapy with cyproterone acetate. In addition, fourteen girls with isosexual precocious puberty not receiving any therapy were tested and served as controls. It was found that cyproterone acetate induces suppression of the responsiveness of the pituitary gland to secrete LH on LHRH stimulation. Daily oral therapy was found to be more effective than the regimen of intramuscular depot injections. These findings demonstrate that cyproterone acetate has an antigonadotrophic effect.