Efficacy
Efficacy
ELIGARD® delivers powerful and sustained testosterone suppression that reflects current science.
ELIGARD® achieves low castration 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. [1]
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. [2]
Castration levels in 2-4 weeks
Testosterone levels increased above baseline during the first week, declining thereafter to baseline levels or below by the end of the second or third week in the majority of patients. Castration levels were generally reached within two to four weeks.
Castration levels maintained
Castration testosterone levels were maintained for the duration of the treatment with ELIGARD 7.5 mg. No increases above the castration level occurred in any of the patients.
Castration levels were maintained for the duration of treatment with ELIGARD 22.5 mg with only one patient demonstrating breakthrough following 1st injection; that patient remained at castration levels following the second injection.
Once castration levels were achieved with ELIGARD 30 mg, most (86/89) patients remained suppressed throughout the study.
Once castration levels were achieved with ELIGARD 45 mg, only one patient (< 1%) experienced a breakthrough, with testosterone levels > 50 ng/dL.
Serum PSA decrease
Serum PSA decreased in all patients in all studies whose baseline values were elevated above the normal limit. [1]
A total of 91% to 95% of patients achieved normal serum PSA values at study conclusion. [1]
Response to ELIGARD should be monitored by periodic measurement of serum concentrations of testosterone and prostate specific antigen.
Dose | 7.5 mg | 22.5 mg | 30 mg | 45 mg |
Mean PSA reduction at study conclusion | 94% | 98% | 86% | 97% |
Patients with normal PSA at study conclusion | 94% | 91% | 93% | 95% |
In all studies, ELIGARD decreased serum PSA in all patients whose baseline values were elevated above normal. [1] |
References
- 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