Sex Steroids and the Serotonin Transporter

Medical University of Vienna

Status and phase: Completed; Phase 4

Conditions: Transsexualism

Treatments: Drug: Testolactone undecanoate; Drug: Lynestrenol; Drug: Cyproterone Acetate; Drug: Estradiol; Drug: 5-alpha reductase inhibitor

Study type: Interventional

Funder types: Other

Identifiers

NCT01065220

AP13214ONB

Details and patient eligibility

About

The aim of this study is to prove the influence of the sex steroid hormones estrogen, progesterone and testosterone on the serotonin transporter (5-HTT) binding using positron emission tomography (PET) and the selective radioligand [11C]DASB. Specifically, the 5-HTT binding will be quantified before and after hormone therapy underwent by 10 male-to-female (MtF) and 10 female-to-male (FtM) transsexuals urging for hormone treatment. The high-level, long-term administration of opsite sex steroid hormones in transsexuals provide the unique opportunity to investigate the influence of sex steroid hormones on the serotonergic system. Since the serotonin transporter serves as a primary target molecule for antidepressant treatment, the results of the study will be of benefit for the assessment of the clinical relevance of estrogen and testosterone as modulatory and neuroactive agents.

Enrollment: 32 patients

Sex: All

Ages: 18 to 55 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• somatic health
• no previous sex hormone medication
• willingness to sign the written informed consent

Exclusion criteria

• severe diseases
• steroid hormone treatment within 6 months prior inclusion
• treatment with psychotropic agents such as selective serotonin reuptake inhibitors (SSRIs)
• any implant or stainless steel graft
• positive urine pregnancy test in women at the screening visit at each PET day

Trial design

Primary purpose: Basic Science

Allocation: Non-Randomized

Interventional model: Single Group Assignment

Masking: None (Open label)

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32 participants in 2 patient groups

hormone treatment for MtF

Experimental group

Description:

* cyproterone acetate * estradiol * alpha-5-reductase-inhibitor

Treatment:

Drug: 5-alpha reductase inhibitor

Drug: Estradiol

Drug: Cyproterone Acetate

hormone treatment for FtM

Experimental group

Description:

* testosterone undecanoate * lynestrenol

Treatment:

Drug: Lynestrenol

Drug: Testolactone undecanoate