Testosterone and Erythrocyte Lifespan.

Context: Endogenous and exogenous androgens increase circulating erythrocytes and hemoglobin but their effects on erythrocyte lifespan is not known.

Objective: To investigate androgen effects on immature and mature erythrocyte lifespan in humans and mice using novel nonradioactive minimally invasive methods.

Design: Human erythrocyte lifespan was estimated using alveolar carbon monoxide concentration and blood hemoglobin in Levitt's formula in hypogonadal or transgender men before and up to 18 weeks after commencing testosterone (T) treatment.

Dried blood spot sampling of testosterone microdosing in healthy females.

Capillary dried blood spot (DBS) analysis coupled with multi-analyte steroid liquid chromatography mass spectrometry (LCMS) is attractive for field studies, home-based self-sampling as well as clinical trials by eliminating costly and laborious sample processing involving venipuncture and frozen storage/shipping while providing multiple steroid measurements from a single small sample. We investigated steroid measurements in DBS samples stored for four years at room temperature prior to analysis compared with the original venipuncture serum samples. Healthy women (n=12) provided paired DBS and blood samples over two weeks run-in before seven days treatment with daily transdermal T gel (12.

Single and multi-dose pharmacology of recombinant and urinary human chorionic gonadotrophin in men.

Objective: Human choriogonadotrophin (hCG) treatment of gonadotrophin-deficient infertile men uses hCG of urinary (uhCG) or recombinant (rhCG) origin, but these treatments have not been compared nor are there studies defining rhCG dosing in men.

Design: hCG products were studied in randomized cross-over single-dose studies of standard (Study 1, 1500 IU and 62.5 µg, respectively) or high (Study 2, 5000 IU and 250 µg) dose and a multi-dose population pharmacology study of hCG use.

Depot Pure GnRH Antagonist for Long-term Treatment of Ovarian Hyperthecosis Monitored by Multisteroid LCMS Profiling.

Ovarian hyperthecosis (OHT), severe hyperandrogenism after menopause in the absence of ovarian or adrenal tumors, is usually treated by surgical excision. We report a 58-year-old woman presenting with severe hyperandrogenism (serum testosterone 15.7-31.

Detection of testosterone microdosing in healthy females.

The ready detectability of synthetic androgens by mass spectrometry (MS)-based antidoping tests has reoriented androgen doping to using testosterone (T), which must be distinguished from its endogenous counterpart making detection of exogenous T harder. We investigated urine and serum steroid and hematological profiling individually and combined to determine the optimal detection model for T administration in women. Twelve healthy females provided six paired blood and urine samples over 2 weeks prior to treatment consisting of 12.

Optimal injection interval for testosterone undecanoate treatment of hypogonadal and transgender men.

Objective: To define the optimized inter-injection interval of injectable testosterone undecanoate (TU) treatment for hypogonadal and transmen based on individual dose titration in routine clinical practice.

Design And Methods: A prolective observational study of consecutive TU injections in men undergoing testosterone replacement therapy for pathological hypogonadism or masculinization of female-to-male transgender (transmen) subject to individual dosing titration to achieve a stable replacement regimen.

Results: From 2006 to 2019, 6899 injections were given to 325 consecutive patients.

Rate and Extent of Recovery from Reproductive and Cardiac Dysfunction Due to Androgen Abuse in Men.

Context: Androgen abuse impairs male reproductive and cardiac function, but the rate, extent, and determinants of recovery are not understood.

Objective: To investigate recovery of male reproductive and cardiac function after ceasing androgen intake in current and past androgen abusers compared with healthy non-users.

Methods: Cross-sectional, observational study recruited via social media 41 current and 31 past users (≥3 months since last use, median 300 days since last use) with 21 healthy, eugonadal non-users.

Testosterone for Androgen Deficiency-Like Symptoms in Men Without Pathologic Hypogonadism: A Randomized, Placebo-Controlled Cross-over With Masked Choice Extension Clinical Trial.

Background: Off-label testosterone prescribing for androgen deficiency (AD)-like sexual and energy symptoms of older men without pathologic hypogonadism has increased dramatically without convincing evidence of efficacy.

Methods: In a randomized, double-blind, placebo-controlled study with three phases, we entered 45 men aged at least 40 years without pathologic hypogonadism but with AD-like energy and/or sexual symptoms to either daily testosterone or placebo gel treatment for 6 weeks in a cross-over study design with a third, mandatory extension phase in which participants chose which previous treatment they preferred to repeat while remaining masked to their original treatment. Primary endpoints were energy and sexual symptoms as assessed by a visual analog scale (Lead Symptom Score [LSS]).

Pharmacokinetics and Acceptability of Subcutaneous Injection of Testosterone Undecanoate.

Context: Can injectable testosterone undecanoate (TU) be administered effectively and acceptably by the subcutaneous (SC) route?

Objective: To investigate the acceptability and pharmacokinetics (PK) of SC injection of TU.

Design: Randomized sequence, crossover clinical study of SC vs IM TU injections.

Setting: Ambulatory clinic of an academic andrology center.

Urine and Serum Sex Steroid Profile in Testosterone-Treated Transgender and Hypogonadal and Healthy Control Men.

Background: The impact of testosterone (T) treatment on antidoping detection tests in female-to-male (F2M) transgender men is unknown. We investigated urine and serum sex steroid and luteinizing hormone (LH) profiles in T-treated F2M men to determine whether and, if so, how they differed from hypogonadal and healthy control men.

Method: Healthy transgender (n = 23) and hypogonadal (n = 24) men aged 18 to 50 years treated with 1000 mg injectable T undecanoate provided trough urine and blood samples and an additional earlier postinjection sample (n = 21).