Читать книгу Anti-Aging Therapeutics Volume XIV - A4M American Academy - Страница 34

Handelsman et al¹ studied the pharmacokinetics and pharmacodynamics of implanted testosterone pellets in a prospective, cross-over clinical trial of 43 androgen deficient men. Three different regimens (6 x 100 mg, 6 x 200 mg; and 3 x 200 mg) were compared. Results showed a consistent, near linear release rate, with levels of total testosterone (TT) and free testosterone (fT) peaking at 1-month. Physiological doses were maintained for approximately 4-months with the 600 mg dose and 6-months with the 1200 mg dose. No difference in TT levels was observed between the 6 x 100 mg and 3 x 200 mg pellets in TT. A difference in fT was noted initially however this was not statistically significant after the first insertion. The authors concluded: “We conclude that fused pellets of crystalline testosterone provides very satisfactory depot androgen replacement exhibiting many desirable features for androgen replacement.”

Jockenhövel et al² conducted a single-dose, non-randomized pharmacokinetic study of 14 hypogonadal men. Participants were implanted with 6 testosterone pellets, each containing 200 mg of fused crystalline testosterone. At the same time the feasibility and side-effects of testosterone pellets were evaluated in another 36 hypogonadal men. Results of the pharmacokinetic study revealed an initial short-lived burst of testosterone release, followed by a stable release level until day 63. Thereafter serum levels of testosterone declined gradually and were close to baseline concentrations by day 300. Therapeutic levels were maintained for up to180 days. Results also showed an initial decline in sex hormone binding globulin (SHBG) levels, an elevation of DHT and E2, and a lower ratio of DHT to testosterone. The only side-effect observed during 112 implantations in the total group of 50 men was 6 local infections, which lead to extrusion of 5 pellets in 3 men. All but one participant (49 of 50 men) preferred testosterone pellets to their previous testosterone medication for TRT. The authors concluded: “Testosterone pellets are the androgen formulation with the longest biological action and strongest pharmacodynamic efficacy in terms of gonadotrophin suppression. The pharmacokinetic features are advantageous compared to other testosterone preparations and the patient acceptance is high.”