Effects of testosterone undecanoate administered alone or in combination with letrozole or dutasteride in female to male transsexuals.
BACKGROUND
Testosterone undecanoate (TU) has potential as androgen therapy for ovariectomized female to male (FtM) transsexual subjects; however, the long-term physiologic effects of TU treatment, the significance of testosterone (T), and the T metabolites dihydrotestosterone (DHT) and estradiol (E) on specific outcome parameters are currently unknown.


OBJECTIVE
The aim of this study was to investigate the long-term treatment of TU with regard to bone metabolism, body composition, and lipid profile in FtM subjects, and to evaluate the relationship between observed effects and circulating levels of T, E, and DHT.


METHODS
Circulating follicle-stimulating hormone, luteinizing hormone, T, E, DHT, and lipid concentrations were measured, as well as bone metabolism, body composition, and insulin resistance.


METHODS
This was a 1-year, randomized treatment, open-label, uncontrolled safety study. Fifteen ovariectomized FtM subjects from an outpatient clinic were divided into three groups to receive TU 1,000 mg alone or in combination with oral administration of letrozole (L) 2.5 mg/die or dutasteride (D) 0.5 mg/die for a period of 54 weeks.


RESULTS
TU alone and TU + D treatments were successful in terms of hormone adjustment, did not result in any adverse effects, and were well-tolerated. Bone mineral density decreased by an average of 0.9 g/cm(2) in the TU + L group, and the addition of D resulted in a failure to gain lean mass.


CONCLUSIONS
This study confirmed that TU is a successful and safe treatment for FtM subjects. These data indicate that E has an important role in bone metabolism and that DHT may play a role in muscle metabolism.
Meriggiola
Maria Cristina
MC
Department of Obstetrics and Gynecology, Center for Reproductive Health, S Orsola Hospital, University of Bologna, Bologna, Italy. cristina.meriggiola@unibo.it
Armillotta
Francesca
F
Costantino
Antonietta
A
Altieri
Paola
P
Saad
Farid
F
Kalhorn
Thomas
T
Perrone
Anna Myriam
AM
Ghi
Tullio
T
Pelusi
Carlotta
C
Pelusi
Giuseppe
G
D000293:Adolescent; D000328:Adult; D047072:Aromatase Inhibitors / Q000627:therapeutic use*; D001378:Azasteroids / Q000627:therapeutic use*; D013196:Dihydrotestosterone / Q000097:blood; D004359:Drug Therapy, Combination; D000068538:Dutasteride; D004791:Enzyme Inhibitors / Q000627:therapeutic use*; D004958:Estradiol / Q000097:blood; D005260:Female; D005640:Follicle Stimulating Hormone / Q000097:blood; D006801:Humans; D000077289:Letrozole; D007986:Luteinizing Hormone / Q000097:blood; D008297:Male; D008875:Middle Aged; D009570:Nitriles / Q000627:therapeutic use*; D012738:Sex Hormone-Binding Globulin; D013739:Testosterone / Q000031:analogs & derivatives* / Q000627:therapeutic use; D014189:Transsexualism; D014230:Triazoles / Q000627:therapeutic use*; D055815:Young Adult
D047072:Aromatase Inhibitors; D001378:Azasteroids; D004791:Enzyme Inhibitors; D009570:Nitriles; D012738:Sex Hormone-Binding Globulin; D014230:Triazoles; D013196:Dihydrotestosterone; D013739:Testosterone; D004958:Estradiol; D000077289:Letrozole; D007986:Luteinizing Hormone; D005640:Follicle Stimulating Hormone; C010792:testosterone undecanoate; D000068538:Dutasteride