A phase II trial with new triptorelin sustained release formulations in prostatic carcinoma

Area of Science:

• Endocrinology
• Oncology
• Pharmacology

Background:

• Prostatic carcinoma treatment often requires androgen deprivation therapy.
• Gonadotropin-releasing hormone (GnRH) agonists are used to achieve medical castration.
• Sustained-release formulations aim to improve treatment adherence and efficacy.

Purpose of the Study:

• To evaluate the efficacy of a single intramuscular injection of triptorelin pamoate sustained release (SR) 11.25 mg in inducing and maintaining pharmacological castration.
• To assess testosterone levels in the castrate range (< 1.735 nmol/l) for up to 3 months in patients with prostatic carcinoma.
• To compare two formulations of triptorelin pamoate 11.25 mg for their pharmacokinetic and safety profiles.

Main Methods:

• Two groups of 10 patients with prostatic carcinoma received one intramuscular injection of triptorelin pamoate SR 11.25 mg.
• Plasma testosterone and triptorelin levels were monitored over a 3-month period.
• Clinical endpoints including pain, micturition, performance status, tolerance, and adverse events were assessed.

Main Results:

• Both triptorelin pamoate formulations successfully induced castration levels of testosterone within 3-4 weeks.
• Testosterone levels remained below 1.735 nmol/l through the 3-month study period.
• One formulation (DLGSD-3-95-21) showed greater bioavailability, leading to a quicker onset of castration and better maintenance of low testosterone levels.

Conclusions:

• Triptorelin pamoate 11.25 mg in microgranules is a safe and effective 3-month sustained-release treatment for advanced prostatic carcinoma.
• The formulation DLGSD-3-95-21 was selected for further clinical use due to its superior bioavailability.
• The study supports the use of this triptorelin formulation for long-term management of prostate cancer.