A Dose Finding Study of a Super Long-Acting Luteinizing Hormone-Releasing Hormone Analog (Leuprolide Acetate Depot, TAP-144-SR) in the Treatment of Central Precocious Puberty.

Abstract

The effect of leuprolide acetate (D-Leu6-[des-Gly10-NH2]-LH-RH ethylamide acetate) for depot suspension (TAP-144-SR), a synthetic analog of luteinizing hormone-releasing hormone, was examined in three doses in 36 patients (34 girls, 2 boys) with central precocious puberty. TAP-144-SR was injected subcutaneously every four weeks for twelve weeks, and clinical symptoms and plasma and urinary levels of various hormones were followed every four weeks. Eleven girls given 10 micrograms/kg showed a significant decrease in peak plasma LH and FSH responses to LH-RH test, but basal plasma LH and FSH did not change significantly. In 13 patients (11 girls and 2 boys) given 30 micrograms/kg and 12 girls given 90 micrograms/kg, both basal and peak LH and FSH were significantly suppressed. Urinary excretion of LH decreased significantly in all groups except in the 10 micrograms/kg group. Urinary excretion of FSH did not change significantly in the 10 and 30 micrograms/kg groups, but it decreased significantly in the 90 micrograms/kg group. In girls, plasma and urinary estradiol also fell greatly, but the difference was insignificant except in the 90 micrograms/kg group. Regression of sexual characteristics was observed in almost half of the patients at the 12th week of the treatment. Side effects were minimal. A dose of more than 30 micrograms/kg of TAP-144-SR is effective in suppressing gonadotropins and causing improvement of clinical symptoms, and appears to be useful in treating children with central precocious puberty.