madman
Super Moderator
Converting men from Clomiphene Citrate to Natesto for hypogonadism improves libido, maintains semen parameters, and reduces estradiol
Parviz K. Kavoussi M.D., G. Luke Machen M.D., Melissa S. Gilkey M.S., Shu-Hung Chen M.S., Keikhosrow M. Kavoussi M.D., Amy Esqueda R.N.C., M.S.N., A.P.R.N., J. David Wininger P.h.D., Maya Barsky M.D., M.S.C.I., Shahryar K. Kavoussi M.D., M.P.H.
Abstract:
Objective: To evaluate outcomes including libido, semen parameters, testosterone, estradiol (E2), follicle-stimulating hormone (FSH), and luteinizing hormone (LH) when converting men with low libido on Clomiphene Citrate (CC) to Natesto.
Methods: A retrospective chart review was performed. Baseline hormones prior to treatment, and again on CC and Natesto, as well as semen parameters on CC and on Natesto, were assessed.
Results: In forty-one men, there was no difference in serum testosterone levels on CC versus Natesto, however; there was a significantly higher E2 on CC than on Natesto. Although FSH levels were significantly lower on Natesto than at baseline, the mean FSH level on Natesto remained in the normal reference range. There was no difference in LH levels at baseline versus on Natesto. There was not a significant difference in semen parameter values when men were on CC versus when they were on Natesto for 3 months. At 3 months after changing to Natesto, 38/41 (92.7%) men reported significantly improved libido on Natesto when compared to CC.
Conclusions: Men on CC and Natesto reach eugonadal testosterone levels, however; on CC the E2 level nearly doubled from baseline and converting men from CC to Natesto returned E2 3 to nearly baseline levels. There was not a detrimental effect on semen parameters, and there was subjective reporting of improved libido after converting from CC to Natesto in this cohort, but further long-term studies are needed prior to Natesto being established as a definitive treatment for hypogonadism for men desiring to maintain fertility.
Introduction
There has been a rise in the prevalence of low testosterone in adolescents and young adults, for whom current or future fertility potential may be important.1,2 Long-acting traditional testosterone replacement therapy (TRT) modalities, such as transdermal gels and intramuscular injections, suppress the gonadotropins follicle-stimulating hormone (FSH) and luteinizing hormone (LH), thereby suppressing spermatogenesis downstream by decreasing intratesticular testosterone levels. 3-5 Clomiphene Citrate (CC) is a selective estrogen receptor modulator, which is an off-label treatment for men with hypogonadism in a spermatogenic preserving manner. The mechanism of action of CC is inhibition of estradiol negative feedback to the hypothalamus resulting in increased secretion of LH stimulating Leydig cells of the testes to produce testosterone. 6 Most men have normalization of testosterone levels on CC to eugonadal levels, but estradiol (E2) levels commonly rise, and symptomatic response on CC has been reported to be less optimal than on TRT, particularly libido. 7 The 4.5% intranasal TRT, Natesto, is administered at a fairly low dose of 11 mg per dose administration and is administered at more frequent intervals of twice or three times daily, which allow FSH and LH to remain in normal reference range levels. A clinical trial by Ramasamy et al revealed that men treated with Natesto did not have significant suppression of semen parameter values from baseline. 8 The objective of the current study was to evaluate the impact of converting men who suffered from low libido on CC to Natesto and assessing the effect on serum testosterone levels, FSH, LH, E2, and semen analysis parameter values, as well as libido.
Conclusions
Although men reached eugonadal testosterone levels on both CC and Natesto, men on CC nearly doubled their E2 levels from baseline, and converting men from CC to Natesto returned E2 to nearly baseline levels. In this patient cohort, there was not a detrimental effect on semen parameters, and there was subjective reporting of improved libido after converting from CC to Natesto, however; there is a need for longer-term studies beyond six months of treatment prior to concluding that Natesto is an appropriate treatment for hypogonadal men desiring to maintain fertility.
Parviz K. Kavoussi M.D., G. Luke Machen M.D., Melissa S. Gilkey M.S., Shu-Hung Chen M.S., Keikhosrow M. Kavoussi M.D., Amy Esqueda R.N.C., M.S.N., A.P.R.N., J. David Wininger P.h.D., Maya Barsky M.D., M.S.C.I., Shahryar K. Kavoussi M.D., M.P.H.
Abstract:
Objective: To evaluate outcomes including libido, semen parameters, testosterone, estradiol (E2), follicle-stimulating hormone (FSH), and luteinizing hormone (LH) when converting men with low libido on Clomiphene Citrate (CC) to Natesto.
Methods: A retrospective chart review was performed. Baseline hormones prior to treatment, and again on CC and Natesto, as well as semen parameters on CC and on Natesto, were assessed.
Results: In forty-one men, there was no difference in serum testosterone levels on CC versus Natesto, however; there was a significantly higher E2 on CC than on Natesto. Although FSH levels were significantly lower on Natesto than at baseline, the mean FSH level on Natesto remained in the normal reference range. There was no difference in LH levels at baseline versus on Natesto. There was not a significant difference in semen parameter values when men were on CC versus when they were on Natesto for 3 months. At 3 months after changing to Natesto, 38/41 (92.7%) men reported significantly improved libido on Natesto when compared to CC.
Conclusions: Men on CC and Natesto reach eugonadal testosterone levels, however; on CC the E2 level nearly doubled from baseline and converting men from CC to Natesto returned E2 3 to nearly baseline levels. There was not a detrimental effect on semen parameters, and there was subjective reporting of improved libido after converting from CC to Natesto in this cohort, but further long-term studies are needed prior to Natesto being established as a definitive treatment for hypogonadism for men desiring to maintain fertility.
Introduction
There has been a rise in the prevalence of low testosterone in adolescents and young adults, for whom current or future fertility potential may be important.1,2 Long-acting traditional testosterone replacement therapy (TRT) modalities, such as transdermal gels and intramuscular injections, suppress the gonadotropins follicle-stimulating hormone (FSH) and luteinizing hormone (LH), thereby suppressing spermatogenesis downstream by decreasing intratesticular testosterone levels. 3-5 Clomiphene Citrate (CC) is a selective estrogen receptor modulator, which is an off-label treatment for men with hypogonadism in a spermatogenic preserving manner. The mechanism of action of CC is inhibition of estradiol negative feedback to the hypothalamus resulting in increased secretion of LH stimulating Leydig cells of the testes to produce testosterone. 6 Most men have normalization of testosterone levels on CC to eugonadal levels, but estradiol (E2) levels commonly rise, and symptomatic response on CC has been reported to be less optimal than on TRT, particularly libido. 7 The 4.5% intranasal TRT, Natesto, is administered at a fairly low dose of 11 mg per dose administration and is administered at more frequent intervals of twice or three times daily, which allow FSH and LH to remain in normal reference range levels. A clinical trial by Ramasamy et al revealed that men treated with Natesto did not have significant suppression of semen parameter values from baseline. 8 The objective of the current study was to evaluate the impact of converting men who suffered from low libido on CC to Natesto and assessing the effect on serum testosterone levels, FSH, LH, E2, and semen analysis parameter values, as well as libido.
Conclusions
Although men reached eugonadal testosterone levels on both CC and Natesto, men on CC nearly doubled their E2 levels from baseline, and converting men from CC to Natesto returned E2 to nearly baseline levels. In this patient cohort, there was not a detrimental effect on semen parameters, and there was subjective reporting of improved libido after converting from CC to Natesto, however; there is a need for longer-term studies beyond six months of treatment prior to concluding that Natesto is an appropriate treatment for hypogonadal men desiring to maintain fertility.