Enclomiphene citrate: A treatment that maintains fertility in men with secondary hypogonadism

Pharmacological management of testosterone deficiency in men current advances and future directions

INTRODUCTION

Testosterone deficiency (TD) is relatively common in aging men, affecting around 2% of the general population. Testosterone replacement therapy (TRT) represents the most common medical approach for subjects who are not interested in fathering.

AREAS COVERED

This review summarizes advances in TRT, including approved or non-approved pharmacological options to overcome TD. When possible, a meta-analytic approach was applied to minimize subjective and biased interpretations of the available data.

EXPERT OPINION

During the last decade, several new TRT formulations have been introduced on the market, including oral, transdermal, and parenteral formulations. Possible advantages and limitations have been discussed appropriately. Anti-estrogens, including selective estrogen modulators or aromatase inhibitors still represent further possible off-label options. However, long-term side effects on sexual function and bone parameters constitute major limitations. Glucagon-like peptide 1 analogues can be an alternative option in particular for massive obesity-associated TD. Weight loss obtained through lifestyle modifications including diet and physical exercise should be encouraged in all overweight and obese patients. A combination of TRT and lifestyle changes can be considered in those subjects in whom a reversal of the condition cannot be expected in a reasonable time frame.

Comprehensive analysis of prohibited substances and methods in sports: Unveiling trends, pharmacokinetics, and WADA evolution

This review systematically compiles sports-related drugs, substances, and methodologies based on the most frequently detected findings from prohibited lists published annually by the World Anti-Doping Agency (WADA) between 2003 and 2021. Aligned with structure of the 2023 prohibited list, it covers all proscribed items and details the pharmacokinetics and pharmacodynamics of five representatives from each section. Notably, it explores significant metabolites and metabolic pathways associated with these substances. Adverse analytical findings are summarized in tables for clarity, and the prevalence is visually represented through charts. The review includes a concise historical overview of doping and WADA's role, examining modifications in the prohibited list for an understanding of evolving anti-doping measures.

Selective modulation of estrogen receptor in obese men with androgen deficiency: A systematic review and meta-analysis

BACKGROUND

Although selective estrogen receptor modulators have been proposed as a treatment for men with central functional hypogonadism, only a few data have been produced in men with obesity-related functional androgen deficiency.

OBJECTIVE

To determine whether and to what extent selective estrogen receptor modulators are an effective and safe therapy in men with obesity-related functional androgen deficiency.

MATERIALS AND METHODS

A thorough search of PubMed, Web of Science, Scopus, and Cochrane Library databases was performed to identify studies comparing testosterone levels before and after treatment. Mean differences with 95% coefficient intervals were combined using random effects models. Funnel plot, Egger's test, and trim-and-fill analysis were used to assess publication bias.

RESULTS

Seven studies met the inclusion criteria providing information on 292 men with obesity-related functional androgen deficiency treated with clomiphene citrate (12.5-50 mg daily) or enclomiphene citrate (12.5-25 mg daily) for 1.5-4 months. The pooled estimates indicated a significant increase in testosterone levels both with clomiphene (mean difference: 11.56 nmol/L; 95% coefficient interval: 9.68, 13.43; I2  = 69%, pfor heterogeneity  = 0.01) and enclomiphene citrate (mean difference: 7.50 nmol/L; 95% coefficient interval: 6.52, 8.48; I2  = 4%, pfor heterogeneity  = 0.37). After the exclusion of one study on severely obese men, who exhibited the highest response rate to clomiphene citrate, the heterogeneity disappeared (mean difference: 10.27 nmol/L; 95% coefficient interval: 9.39, 11.16; I2  = 0%, pfor heterogeneity  = 0.66). No publication bias was revealed by Egger's test and trim-and-fill analysis. No treatment-related unexpected findings regarding safety profile were registered.

DISCUSSION AND CONCLUSION

Treatment with clomiphene citrate and enclomiphene citrate may be an effective and safe alternative to testosterone replacement therapy in men with obesity-related functional androgen deficiency. Further long-term studies are warranted to define clinical reflections of the selective estrogen receptor modulators-induced increase in testosterone levels and to better clarify the safety profile.

Efficacy of Clomiphene Citrate Versus Enclomiphene Citrate for Male Infertility Treatment: A Retrospective Study

Introduction Infertility and hypogonadism in males can greatly affect their reproductive health and overall well-being. Since exogenous testosterone administration for hypogonadism management may disrupt the normal hormonal cascade necessary for spermatogenesis, clomiphene citrate (CC) and enclomiphene citrate (EC) are medications often used to manage hypogonadism and male infertility. This study aims to directly compare the effects of CC and EC on serum testosterone levels and semen parameters in men to determine which medication may have an advantage in managing these conditions. Materials and methods We retrospectively analyzed ≥18-year-old men presenting with primary infertility, abnormal semen parameters, or hypogonadism who received CC or EC monotherapy for at least three months between January 2021 and December 2022. We compared baseline and follow-up hormone levels, semen parameters, and demographics. Variables were compared using paired and unpaired t-tests. Significance was assessed at p<0.05. Results A total of 46 men received EC and 32 men received CC. The median age was 42 (IQR: 34-47.75) years in men who received EC and 41 (IQR: 36-44) years in men who received CC (p=0.450). The two treatment groups exhibited a significant increase in serum total testosterone, while only EC had a statistically significant increase in FSH and LH. Semen volume and concentration did not significantly change with either treatment. Sperm motility increased in both groups, but total motile sperm count (TMSC) only significantly increased in men who received EC.  Conclusions Our study found that EC and CC are effective treatments in increasing total testosterone without negatively affecting spermatogenesis. EC demonstrated to be more effective in raising gonadotropin levels and TMSC.

Reproductive axis ageing and fertility in men

Compared to women, increasing male age is not accompanied by such marked changes in reproductive function but changes certainly do happen. These include alterations to the hypothalamo-pituitary-testicular axis, with resultant implications for testosterone production and bioavailability as well as spermatogenesis. There is a decline in sexual function as men age, with a dramatic increase in the prevalence of erectile dysfunction after the age of 40, which is a marker for both clinically evident as well as covert coronary artery disease. Despite a quantitative decline in spermatogenesis and reduced fecundability, the male potential for fertility persists throughout adult life, however there are also increasingly recognised alterations in sperm quality and function with significant implications for offspring health. These changes are relevant to both natural and medically assisted conception.

Effectiveness of Clomiphene Citrate for Improving Sperm Concentration: A Literature Review and Meta-Analysis

Demographic data regarding male infertility suggest an increase in prevalence. This is an entity with multifactorial etiology, hormonal causes are often encountered. Although treatment with clomiphene was advocated to stimulate gametogenesis, it is still used off-label. We aimed to evaluate data from literature related to the effect of clomiphene as a single therapy, on the improvement of sperm count in infertile patients. Out of the 4,017 results of the search, only eight articles have been selected. The selected studies have been published between 1983 and 2020, and have included a total of 616 patients. From data reported, the treatment with clomiphene lead to a significant improvement of sperm concentration compared with placebo or with the level before starting the therapy (p<0.00001). Out of the 616 patients, in 369 (59.90%) cases improved sperm concentration was reported. In our meta-analysis, the selected studies had a high heterogeneity (I² = 97%). Nevertheless, clomiphene is not an ideal treatment, paroxysmal effects have been reported. Our findings encourage the use of clomiphene on male infertility, although the potential side effects should be clearly explained to patients.

Testosterone kinetics on hypogonadal men under clomiphene

OBJECTIVE

To evaluate total testosterone (TT) kinetics and its predictors 6 months after the discontinuation of clomiphene citrate (CC) in patients with hypogonadism.

MATERIALS AND METHODS

Consecutive patients with normal testicles and male hypogonadism defined by TT < 300 ng/dl in the presence of signs or symptoms according to the previous consensus were prospectively evaluated in a urologic outpatient clinic by TT levels at baseline (T₀), after a daily dose of 50 mg CC for 40 days (T₁), and after the washout period of 6 months of CC discontinuation (T₂).

RESULTS

Among 75 patients, mean age 56.8 years, testosterone at T₁ > 300 ng/dl was achieved by 69 (92%), 450-600 ng/dl by 32 (42.6%), and > 600 ng/dl by 27 (36.0%). 18 subjects (24%) maintained asymptomatic and TT levels over 300 ng/dl at T₂. Age negatively related to testosterone response and T₁ response > 810 ng/dl predicts a median gain of 166.5 ng/dl at 6 months of CC discontinuation.

CONCLUSIONS

CC is a compelling option to treat male hypogonadism, although a chronic treatment is needed in most patients. About one in every four patients respond to a CC short trial to "reboot" the physiology. Further understanding of TT kinetics in these patients in the long term is warranted.

Evaluating the Combination of Human Chorionic Gonadotropin and Clomiphene Citrate in Treatment of Male Hypogonadotropic Hypogonadism: A Prospective Study

Background

In this study, we evaluated MHH patients who wished to preserve fertility, assessing the efficacy of a short course (12 months) of a combined hCG +clomiphene citrate.

Materials and Methods

The cross-sectional study included 19 patients with hypogonadotropic hypogonadism who were admitted to the Andrology and Fertility Hospital of Hanoi between March 2016 and March 2018. Using hCG every three days in combination with clomiphene citrate 25mg per day until normal testosterone levels are reached, maintain the dose until spermatozoa are present.

Results

The mean age was 30.2 ± 5.6. Differences in penis length between the time before and after treatment were significant (p=0.005). The average dose of hCG using in our study was 5579 ± 1773.7 IU. After treatment 6 months and 12 months, the changes in clinical features in all patients and the total hypogonadotropic hypogonadism group were statistically significant (p<0.001). In particular, the differences in testosterone hormone levels in the partial hypogonadotropic hypogonadism group were also statistically significant (p=0.03). No adverse event was observed in our study. The number of patients appearing sperm in the semen is 9 patients (47.4%) after 12 months, but most of the sperm were completely deformed (<1%), and the average motility in the progressive motility group was below 8%.

Conclusion

In conclusion, a combination of hCG and clomiphene citrate may be an option for MHH patients who desired fertility. After 12 months, 47.4% of patients have sperm in semen but almost all of them were deformity. Hormone profile and secondary sexual characteristics improved significantly. There was no adverse event in our study that considered it as safe therapy.

Anabolic steroid misuse and male infertility: management and strategies to improve patient awareness

Introduction: Anabolic androgenic steroid use is an uncommon but important cause of male infertility. As paternal age and anabolic steroid use increases, providers are more likely than ever to encounter men with infertility and prior or concurrent anabolic steroid use. In this review, we outline the background, epidemiology and pathophysiology of anabolic steroid induced male infertility and provide recommendations regarding the diagnosis, management, and future prevention of this condition.Areas covered: Male reproductive physiology is a tightly regulated process that can be influenced by exogenous sources such as anabolic steroids and selective androgen receptor modulators (SARMs). Data suggest that a combination of selective estrogen receptor modulators (SERMs), human chorionic gonadotropin (hCG), aromatase inhibitors (AIs), and recombinant follicle-stimulating hormone (rFSH) may lead to spermatogenesis recovery.Expert opinion: Anabolic steroid and SARM users continue to exhibit lack of understanding regarding the potential side effects of their use on male fertility. Current literature suggests that spermatogenesis can be safely recovered using a combination of SERMs, hCG, AIs and rFSH although additional studies are necessary. While anabolic steroid prevention strategies have largely been focused on the individual level, further investigation is necessary and should be approached in a socioecological manner.

Leydig stem cells and future therapies for hypogonadism

PURPOSE OF REVIEW

In this review, we outline the most recent advances in the development of Leydig stem cells (LSCs) and summarize the current and upcoming treatments for hypogonadism.

RECENT FINDINGS

In-vitro and in-vivo studies show that inducing stem cells to differentiate into testosterone-producing adult Leydig cells is possible. In addition, LSCs can be grafted with Sertoli cells to increase testosterone levels in vivo. This therapy causes minimal effects on luteinizing hormone and follicle stimulating hormone levels. Novel therapies for hypogonadism include varying methods of testosterone delivery such as intranasal and oral agents, as well as novel selective estrogen and androgen receptor modulators.

SUMMARY

LSC therapies provide an effective way of increasing testosterone levels without detrimentally affecting gonadotropin levels. Next steps in developing viable Leydig cell grafting options for the treatment of hypogonadism should include the assessment of efficacy and potency of current animal models in human trials. Recently, both intranasal and oral testosterone have been made available and shown promising results in treating hypogonadism while maintaining fertility. Enclomiphene citrate and selective androgen receptor modulators have been suggested as future therapies for hypogonadism; however, further studies assessing efficacy and adverse effects are needed.

New testosterone 2% gel using Ferring Advanced Skin Technology (FAST), for the treatment of testosterone deficiency in men, with a novel applicator

INTRODUCTION

Testosterone deficiency (TD) is an increasing problem that can affect a man's physical and psychological health, and quality of life. Testosterone replacement therapy (TRT), combined with weight reduction, lifestyle advice, and the treatment of co-morbidities, is the treatment of choice in men who are not concerned about fertility. However, there remains an unmet need in this therapeutic area, relating to factors such as inconvenient or painful administration, fluctuations in testosterone levels, supra-physiologic testosterone levels, poor tolerability, and secondary safety issues, which may be associated with the current TRT options. Advances in transdermal delivery systems have resulted in the development of a new 2% transdermal testosterone gel, that may offer some additional features over the other currently available TRTs.

AREAS COVERED

We performed a comprehensive review of the published and gray literature to identify randomized studies and non-randomized studies (NRS) involving adult men receiving treatment for low testosterone levels.

EXPERT OPINION

Topical gels are often the most convenient first-line treatment for testosterone deficiency, but options are important as patient preference is more important than virtually any other clinical area of medicine. The chosen therapy must be convenient to use and reach reliable therapeutic levels to effectively and consistently relieve symptoms. Testavan, a new 2% testosterone gel, goes some way to achieving these goals.

Selective estrogen receptor modulators in the prevention of breast cancer in premenopausal women: a review

The detection of premenopausal women at high risk of breast cancer is key to chemoprevention. Therapy with selective estrogen receptor modulators (SERMs) induces a significant antiproliferative effect in estrogen receptor (ER) positive breast cancer. This review was designed according the guidelines of the 2009 PRISMA statement. Searching different databases, including PubMed, MedlinePlus, PLoS One, Cochrane Breast Cancer Specialized Register, Clinical Trials.gov and American Society of Clinical Oncology. From 168 records screened, 15 full text articles were assessed for eligibility and only 7 studies met the inclusion criteria. Three of the studies included analyzed changes in Ki-67 expression, revealing weaker expression after treatment with acolbifene and raloxifene (P<0.001). Three studies also analyzed the breast volume by magnetic resonance imagining (MRI) and demonstrate a significant difference after 1 year with raloxifene treatment (P=0.0017). Moreover, a 20% reduction in breast density was observed after a 2-year treatment with tamoxifen in premenopausal women. SERMs reduce the risk of developing breast cancer. The studies reviewed here demonstrate the modulation of Ki-67 expression and changes in breast density, suggesting an important preventive role for this group of drugs in prevention for premenopausal women at high risk of developing breast cancer.

Pre-treatment estradiol does not predict testosterone response to clomiphene citrate

Background

Clomiphene citrate (CC) is a selective estrogen receptor modulator (SERM) used to stimulate ovulation in women. CC is used off-label in men to increase levels of endogenous testosterone (T) while potentially improving semen parameters by downregulating the inhibitory feedback of estradiol (E) on the male hypothalamus. Our objective was to determine whether pre-treatment E level is associated with greater total testosterone (TT) response to treatment with CC in men with low T.

Methods

Following IRB approval (The University of Miami IRB No. 20170849), retrospective chart review was performed for all men prescribed CC (25 mg every other day) between January 1, 2015 and December 31, 2018. Age, body mass index (BMI), and prescription date were recorded for all patients. Pre- and post-treatment E, total T (TT), follicle-stimulating hormone (FSH), and luteinizing hormone (LH) levels were recorded for all patients as well. Only men with pretreatment TT <300 ng/dL were included in the analysis in order to focus our study on men with low TT. Univariate linear regression analysis was performed to determinate the percent change in TT following CC treatment (dependent variable) and pre-treatment E and other variables including age, BMI, FSH, and LH (independent variables).

Results

A total of 69 men with TT <300 ng/dL received CC 25 mg every other day. Mean age and BMI were 33.3±7.31 years and 35.4±5 kg/m² respectively. Median pre-treatment E, TT, FSH, and LH were 18 [11.35–24.6] pg/mL, 226 [156–262] ng/dL, 5.1 [2.98–8.05] mIU/mL, and 4.5 [2.6–6.8] mIU/mL respectively. Post-treatment TT was 389 [263–592] ng/dL and TT% change was 102 [45.51–176.75]. Univariate linear regression showed that pre-treatment E (B=−0.595; R²=0.001; P=0.757) did not significantly predict TT% change. TT% change could be significantly predicted by age in years (B=−7.428; R²=0.057; P=0.048), pre-treatment FSH (B=−8.362; R²=0.068; P=0.041), and pre-treatment LH (B=−20.67; R²=0.096; P=0.027).

Conclusions

Pre-treatment E level does not appear to predict treatment response with CC in men with low T.

Non-testosterone management of male hypogonadism: an examination of the existing literature

Testosterone deficiency is defined as a total testosterone level <300 ng/dL confirmed on two early morning lab draws. Testosterone therapy has historically been offered to men with symptomatic testosterone deficiency in the form of injections, gels, or pellets. However, these treatments are invasive or have undesirable effects including the risk of drug transference. Additionally, testosterone therapy has been associated with increases in hematocrit and controversy remains regarding the risk of cardiovascular and thromboembolic events while on testosterone therapy. As such, much interest has recently been focused on alternative treatment options for testosterone deficiency in the form of orally-administered medications with more favorable side effect profiles. Lifestyle modifications and varicocelectomy have been shown to raise endogenous testosterone production. Similarly, SERMs and aromatase inhibitors (AIs) have been shown to raise testosterone levels safely and effectively. Human chorionic gonadotropin (hCG) remains the only FDA-approved non-testosterone treatment option for testosterone deficiency in men. However, this medication is expensive and requires patient-administered injections. Over the counter herbal supplements and designer steroids remain available though they are poorly studied and are associated with the potential for abuse as well as increased hepatic and cardiovascular risks. This review aims to discuss the existing treatment alternatives to traditional testosterone therapy, including efficacy, safety, and side effects of these options. The authors suggest that the SERM clomiphene citrate (CC) holds the greatest promise as a non-testosterone treatment option for testosterone deficiency.