Efficacy and safety of recombinant human follicle-stimulating hormone in men with isolated hypogonadotropic hypogonadism

FERTILITY AND STERILITY威 VOL. 77, NO. 2, FEBRUARY 2002 Copyright ©2002 American Society for Reproductive Medicine Published by Elsevier Science Inc. Printed on acid-free paper in U.S.A.

Efficacy and safety of recombinant human follicle-stimulating hormone in men with isolated hypogonadotropic hypogonadism Pierre Bouloux, M.D.,a David W. Warne, Ph.D.,b and Ernest Loumaye, M.D.,c for the FSH Study Group in Male Infertility Royal Free Hospital, London, United Kingdom; Northern General Hospital, Sheffield, United Kingdom; Hoˆpital de l’Antiquaille, Lyon, France; Centre Hospitalier Universitaire Re´gional, Lille, France; Hoˆpital Kremlin Biceˆtre, Kremlin Biceˆtre, France; Medizinisches Zentrum fu¨r Hautkrankheiten der Phillips-Universita¨t, Marburg, Germany; Serono International S.A., Geneva, Switzerland

Received May 15, 2001; revised and accepted October 8, 2001. Financial support provided by Serono International, S.A., Geneva, Switzerland. Presented at the 190th Meeting of the Society for Endocrinology, London, England, November 8 –9, 1999. Reprint requests: Ernest Loumaye, M.D., Serono Inc., 100 Longwater Circle, Norwell, Massachusetts 02061 (FAX: 781-681-2989; E-mail: ernest.loumaye@ serono.com). a Centre for Neuroendocrinology, Royal Free Hospital. b Research and Development—Biometrics, Serono International S.A. c Clinical Development and Regulatory Affairs, Serono Inc., Norwell, Massachusetts. 0015-0282/02/$22.00 PII S0015-0282(01)02973-9

270

Objective: To assess the efficacy and safety of recombinant human follicle-stimulating hormone (rhFSH; follitropin alpha) in increasing sperm concentration in 26 men with severe isolated hypogonadotropic hypogonadism (IHH). Design: Clinical and endocrine studies using an open design. Setting: Six university clinical sites in three European countries. Patient(s): Azoospermatic patients aged 16 to 48 years with IHH. Intervention(s): Patients received hCG for up to 6 months before 18 months of treatment with rhFSH. Sperm count, motility, and morphology were assessed every 3 months. Main Outcome Measure(s): Achievement of a sperm concentration of 1.5 ⫻ 106/mL. Result(s): Spermatogenesis was achieved in 15 of 19 patients who could be evaluated, 12 achieving a sperm concentration of ⱖ 1.5 ⫻ 106/mL. Conclusion(s): With hCG, rhFSH is effective in initiating spermatogenesis in patients with IHH, and is well tolerated. (Fertil Steril威 2002;77:270 –3. ©2002 by American Society for Reproductive Medicine.) Key Words: Male, hypogonadotropic hypogonadism, recombinant human follicle-stimulating hormone, hCG, spermatogenesis, testis

Isolated hypogonadotropic hypogonadism (IHH) in men is a congenital disorder characterized by delayed or absent sexual maturation. Patients with IHH require prolonged treatment with both hCG and FSH to induce and maintain spermatogenesis (1). Previously, gonadotropin therapy has involved the use of urine-derived hCG and urine-derived hMG as a source of FSH. Recombinant human FSH (rhFSH) has now been shown to be both well tolerated and effective for the stimulation of follicular development in infertile women (2). This paper reports the safety and efficacy of rhFSH in men with severe IHH.

MATERIALS AND METHODS The relevant institutional review boards approved the protocol, patient Informed Consent

Form, and Investigator Brochure. Informed consent was obtained from all patients. Thirty-two azoospermic men with IHH, aged 16 to 48 (mean 25.9 ⫾ 7.7) years, took part in the study. In 20 patients, IHH was idiopathic; in 12 it was due to Kallmann’s syndrome. Eligibility criteria for enrollment in the study included a mean testicular volume ⱕ4 mL (assessed using a Prader Orchidometer); no testosterone therapy for 5 weeks and no hCG therapy for 2 weeks before entry; no evidence of pituitary or hypothalamic lesion; and no use of drugs that could affect testicular function. The serum levels of cortisol, FSH, LH, prolactin, testosterone, thyroxine, and TSH for participants were within predetermined ranges. Body mass index was measured at ⱕ 30.9 kg/m2. No patient was to have an illness that could affect testicular function (two

patients later diagnosed with cryptorchidism were withdrawn from the primary efficacy evaluation). Patients were pretreated for up to 6 months with hCG (Profasi, Serono, Aubonne, Switzerland), 2,000 IU twice weekly; the dose was titrated after 2 months to maintain serum testosterone within the normal range. Patients then received 18 months of treatment with hCG together with rhFSH (follitropin alpha; Gonal-F, Serono), 150 IU three times a week, which could be increased to 225 IU after 9 months. Both hormones were administered subcutaneously. Hormone (testosterone, estradiol, FSH, and inhibin) assays, semen analysis, physical and urogenital examinations, hematology and clinical chemistry assessments, and assays for FSH antibodies in serum were carried out at regular (generally 3-month) intervals. The primary efficacy end point was achievement of a sperm concentration ⱖ 1.5 ⫻ 106/mL, which is compatible with fertility (3). Secondary end points were mean testicular volume, serum inhibin concentration, ejaculate volume, sperm count per ejaculate, sperm morphology and motility, and pregnancy in couples desiring fertility. Secondary sexual characteristics and safety were assessed. Changes in efficacy variables at the end of rhFSH treatment were compared with two-sided paired t-tests where appropriate. Mean values ⫾ SD are shown in the text.

RESULTS Of 32 patients screened for eligibility, 26 received rhFSH and were assessed at least once. Seven were excluded from the principal efficacy analysis because of protocol violations, leaving 19 patients to evaluate. In three patients (11.5%), the FSH dose was increased to 225 IU three times per week after 9 months. Twelve of 19 (63.2%) eligible patients achieved a sperm concentration of 1.5 ⫻ 106/mL, three (15.8%) achieved a sperm concentration of 1.0 ⫻ 106/mL, and four remained azoospermic. The mean increase in sperm concentration at 9 months was 2.8 ⫻ 106/mL (P⫽.027). The median time to initiation of spermatogenesis was 9 months, and to achieve a sperm concentration of 1.5 ⫻ 106/mL was 18 months (Fig. 1A). Mean sperm count per ejaculate was significantly increased at 12 months (P⫽.037) and reached 32.5 ⫻ 106 at the end of treatment. After 9 months, 39.1% (P⫽.001) of sperm showed a normal morphology with no subsequent significant change. The proportion of sperm with normal motility (WHO Grade A) reached 25.6% at 9 months (P⫽.001); from 12 months, it reached approximately 40%, which was maintained for the remainder of the study. There was no statistically significant change in ejaculate volume during treatment. Changes in serum testosterone, estradiol, and FSH concentrations are summarized in Figure 1B–D. Mean testicular FERTILITY & STERILITY威

volume increased from 2.5 ⫾ 1.0 mL to 12.2 ⫾ 4.9 mL during 18 months of rhFSH treatment (see Fig. 1E). Six pregnancies, five of which went successfully to term, occurred in four of seven couples who wished to conceive. Four serious adverse events occurred, only one of which, testicular surgery for undiagnosed cryptorchidism, was thought related to rhFSH treatment. Analysis of 5762 rhFSH injection site observations showed 0.1% (seven injections), 1.3%, and 6.4% evoked severe, moderate, or mild reactions, respectively. Serum antibodies to FSH were not detected. Increases in red blood cell count, hemoglobin, packed cell volume, and creatinine over the course of the study reflected increases in testosterone concentrations.

DISCUSSION Although clinical experience with rhFSH is considerable in female indications, it is still very limited in male patients with IHH because of the rarity of this condition. Therefore, this study with rhFSH in IHH was performed to determine the efficacy and safety of rhFSH treatment in such men. An open design was used because IHH does not resolve without treatment, so each patient could serve as his own control, and because inclusion of a comparative group would not have improved the objectivity of the assessments. Furthermore, gonadotropin replacement is established therapy for IHH, and thus the inclusion of a placebo group would have been unacceptable on ethical grounds. The results of this study show that rhFSH is effective in initiating spermatogenesis in the majority of patients with IHH. The primary end point, achievement of a sperm concentration of at least 1.5 ⫻ 106/mL, was reached in 63% of patients, and some degree of spermatogenesis was achieved in 79%. It is known that gonadotropin replacement therapy may not always result in the attainment of normal sperm concentrations (⬎ 20 ⫻ 106/mL); however, Burris et al. (3) have previously shown that a low sperm concentration (⬍1 ⫻ 106/mL) does not preclude fertility in men with IHH. Treatment with rhFSH in the present study was also associated with significant improvements in the secondary efficacy end points of sperm motility and morphology. Successful pregnancies were achieved in four out of seven couples who wished to conceive. Although spontaneous pregnancies are known to occur in patients with IHH treated with hCG and FSH, the use of assisted reproductive technologies, in particular intracytoplasmic sperm injection (ICSI), would be appropriate for couples wishing to conceive. Unlike assessment of the primary efficacy end point, which was determined in the evaluable patient population, secondary end points were assessed in all 26 patients who received rhFSH. The rationale for this decision was that assessment of all patients who received rhFSH and who had undergone at least one assessment more accurately reflected the situation likely to be seen by the clinician. The inclusion 271

FIGURE 1 (A), The proportion (cumulative %) of 19 evaluable patients with IHH who achieved a detectable sperm density (⬎ 0/mL, dashed line) and a sperm density ⱖ 1.5 million/mL (solid line) during 18 months of treatment with hCG and rhFSH. (B), The mean (⫾ SD) levels of testosterone (nmol/L) at the start of the study, after pretreatment with hCG, and during 18 months of treatment with hCG and rhFSH. The change during pretreatment with hCG was statistically significant (P ⬍.001, Student’s paired t-test). (C), The mean (⫾ SD) levels of estradiol (pmol/L) at the start of the study, after pretreatment with hCG, and during 18 months of treatment with hCG and rhFSH. The change during pretreatment with hCG was statistically significant (P⫽.028, Student’s paired t-test). (D), The mean (⫾ SD) levels of FSH (IU/L) at the start of the study, after pretreatment with hCG, and during 18 months of treatment with hCG and rhFSH. Although the peak hormone concentration was not reached for 18 months, a value close to this was achieved within 3 months of beginning rhFSH administration. (E), The mean (⫾ SD) mean testicular volume (mL) at start of study, after pretreatment with hCG, and during 18 months of treatment with hCG and rhFSH.

Bouloux. rhFSH: efficacy/safety in men with IHH. Fertil Steril 2002.

272

Bouloux et al.

rhFSH: efficacy/safety in men with IHH

Vol. 77, No. 2, February 2002

of two patients who were later excluded from the study, for example, demonstrated that it is not always straightforward for the physician to distinguish retractile testis from cryptorchidism. Indeed, these more realistic assessments are being increasingly demanded by regulatory authorities. All patients in this study were azoospermic at baseline, with mean testicular volumes of 4 mL or less. These inclusion criteria were more rigorous than those used in most previous studies of gonadotropin replacement therapy in IHH, in which FSH deficiency may have been present (4). Nevertheless, response to rhFSH was comparable with that seen in previous studies, in which approximately 80% of patients showed some degree of spermatogenesis within 18 months and testicular volume increased by approximately 10 mL. The median time to response in this study was 9 months, which is shorter than that with hMG (4). This apparent difference in response times may be attributable to the fact that in most hMG studies the weekly gonadotropin dose was 225 or 300 IU, whereas in the current study and in studies with highly purified FSH the weekly dose was 450 IU. Of interest are four patients who did not respond within the allocated 18 months of therapy, although they did not present any protocol deviation. These four cases illustrate the heterogeneity of the male IHH population. In two cases, in spite of good treatment compliance, adequate FSH absorption, and appropriate testosterone levels, testicular volume increase was very slow and no spermatogenesis was recorded during 18 months of treatment. In another case with a similar response profile, addition of hGH resulted in spermatogenesis, suggesting possible hGH deficiency. Another patient may have had obstructive azoospermia associated with his hypogonadotropic hypogonadism, as his response to treatment appeared normal, including changes in testis volume. No statistically significant difference in serum T and FSH levels was recorded between the responders and nonresponders in this study, although nonresponders had lower increases in testicular volume. Absence of response in these patients may therefore reflect an undefined underlying condition (e.g., GH deficiency) or a lower sensitivity to FSH that would indicate a higher dose of FSH. Importantly, this study has shown that rhFSH is well tolerated in men with IHH. Of the four serious adverse events reported, only one was considered to be possibly related to rhFSH. In this case, testicular size increase result-

FERTILITY & STERILITY威

ing from treatment helped to identify previously undiagnosed cryptorchidism, which was treated surgically. Local reactions at the injection site occurred in fewer than 10% of patients, and the majority of such reactions were mild or moderate in severity. The increased testosterone production induced by gonadotropin therapy (Figure 1) produced the expected clinical and biochemical effects, including potentially beneficial increases in erythropoiesis and serum creatinine (a marker of increased muscle mass). Confirming observations that have been made in extensive experience with rhFSH in female patients, rhFSH was not found to be immunogenic when given as long-term treatment in male patients. This study has shown that rhFSH (follitropin alpha), at a dosage of 150 IU three times weekly, is effective in initiating spermatogenesis in the majority of male IHH patients pretreated with hCG. A minority of patients may require longer treatment duration or higher doses. Treatment has been shown to be well tolerated over periods of at least 18 months.

Acknowledgments: The authors thank Dr. G. Matfin, Dr. J. Kirk, Professor G. M. Besser, and Dr. R. Quinton for recruiting patients, and Dr. J. Illingworth, Dr. S. Lancaster, Mrs. A. Zrener, Ms. S. Rabut-Navarre, and Ms. D. Guitton-Rebrioux for clinical center monitoring and Mrs. L. Remondino for managing the database. The FSH Study Group in Male Infertility: Pierre Bouloux, M.D., Royal Free Hospital, London, UK; Thomas H. Jones, M.D., Northern General Hospital, Sheffield, UK; Michel Pugeat, M.D., Hoˆ pital de l’Antiquaille, Lyon, France; Didier Dewailly, M.D., Centre Hospitalier Universitaire Re´ gional, Lille, France; Gilbert Schaison, M.D., Hoˆ pital Kremlin Biceˆ tre, Kremlin Biceˆ tre, France; Walter Krause, M.D., Medizinisches Zentrum fu¨ r Hautkrankheiten der Phillips-Universita¨ t, Marburg, Germany; David W. Warne, Ph.D., Genevieve Decosterd, M.Sc., Ernest Loumaye, M.D., Serono International S.A., Geneva, Switzerland.

References 1. Finkel DM, Phillips JL, Snyder PJ. Stimulation of spermatogenesis by gonadotropins in men with hypogonadotropic hypogonadism. N Engl J Med 1985; 313:651–5. 2. Recombinant Human FSH Product Development Group. Recombinant follicle stimulating hormone: development of the first biotechnology product for the treatment of infertility. Hum Reprod Update 1998;4:862– 81. 3. Burris AS, Clark RV, Vantman DJ, Sherins RJ. A low sperm concentration does not preclude fertility in men with isolated hypogonadotropic hypogonadism after gonadotropin therapy. Fertil Steril 1988;50:343–7. 4. Saal W, Baum RP, Happ J, Schmidt M, Cordes U. Subcutaneous gonadotropin therapy in male patients with hypogonadotropic hypogonadism. Fertil Steril 1991;56:319 –24.

273