Low Castrate T Levels
Low Castrate T Levels
ELIGARD® achieves low castrate testosterone levels across all doses. In the United States, the biochemical and regulatory definition of castration is a serum testosterone (T) level <50 ng/dL.
This value is based on the sensitivity of the assays available when androgen deprivation therapy (ADT) was first developed 50 years ago. With the advent of current improved assays, it is possible to detect much lower T levels (<3 ng/dL).
Data were pooled from four prospective, open-label, fixed dose clinical trials in patients with advanced prostate cancer. Patients with no prior ADT were treated with one of four formulations of subcutaneous leuprolide acetate (ELIGARD®):
- 7.5 mg every 28 days for 24 weeks (1-month formulation; n=120)
- 22.5 mg every 84 days for 24 weeks (3-month formulation; n=117)
- 30 mg every 112 days for 32 weeks (4-month formulation; n=90)
- 45 mg every 168 days for 48 weeks (6-month formulation; n=111)
In the pooled patient population, 99%, 97%, 91% and 80% of patients reached nadir testosterone levels of ≤20, ≤10, ≤5, and ≤3 ng/dL respectively, at week 24. 
The mean proportions of time T suppression was maintained below each target were 100% for T ≤50 ng/dL, 94% to 99% for T ≤20 ng/dL, and 66% to 85% for T ≤10 ng/dL. 
All doses achieved and maintained mean serum testosterone to ≤20 ng/dL over 24 weeks with all four dose formulations, and reaching nadir T ≤3 ng/dL in 80% of patients. During the trial of the six-month formulation, testosterone suppression to ≤20 ng/dL was achieved in four weeks, and the mean serum testosterone concentration remained below this level for six months. 
- ELIGARD® (leuprolide acetate) for injectable suspension, 7.5 mg, 22.5 mg, 30 mg, 45 mg prescribing information. Fort Collins, CO: Tolmar Therapeutics, Inc.; 2019
- Pieczonka C, et al., Rev Urol 2018
National Comprehensive Cancer Network, NCCN Guidelines: Prostate Cancer, Version 4. 2019: National Comprehensive Cancer Network website. https://www.nccn.org/professionals/physician_gls/default.aspx#site. Accessed January 2019
- Shore N, et al., BJU Int. 2016