Table 1.
Results of studies of the histrelin implant for the treatment of central precocious puberty
| Study | Number of patients | Peak stimulated LH results (mIU/ml) | Radiographic findings | Growth velocity SDS | Adverse events |
|---|---|---|---|---|---|
| Pilot study4 | 11 (all girls) | Baseline 1.3 ± 1.34 6 mo 0.2 ± 0.06* 9 mo 0.25 ± 0.08* 12 mo 0.28 ± 0.08* 24 mo 0.25 ± 0.08* |
BA–CA: Baseline 1.7 ± 0.5 9 mo 0.6 ± 0.4 |
Baseline 2.8 ± 1.7 9 mo −3.1 ± 2.2 |
Minor local infection (1) Suture inserted into implant (1) Spontaneous extrusion at 6 weeks (1) |
| Phase III study9 | 36 (33 girls) (20 naïve) |
Naïve group Baseline 28.2 ± 20 1 mo 0.8 ± 0.4* Pretreated group Baseline 2.1 ± 2.1 1 mo 0.5 ± 0.3* |
Δ(BA/CA) Baseline to 12 months: Naïve group −0.08 ± 0.08* Pretreated group −0.09 ± 0.06* All −0.08 ± 0.07* |
Naïve group 12 mo −1.8 ± 2.5 Pretreated group 12 mo 0.6 ± 2.3 |
Implant site reactions (18) Implant broken upon removal (7) Ultrasound localization needed for removal (1) |
| Two-year results10 | 31 (29 girls) (18 naïve) |
Naïve 12 mo 0.92 ± 0.58 24 mo 0.51 ± 0.33* Pretreated group 12 mo 0.74 ± 0.50 24 mo 0.45 ± 0.35* |
Δ (BA/CA) 12 to 24 months: −0.07 ± 0.04* |
12 mo −0.42 ± 2.4 24 mo −1.75 ± 3.05* |
Implant site reactions (19) Ultrasound localization needed for removal (3) Breakage upon removal (5) Scar (2 reported, 1 keloid) |
*
statistically significant change from baseline (p < 0.05).
Abbreviations: BA, bone age; CA, chronological age; LH, luteinizing hormone; SDS, standard deviation score; Δ(BA/CA), change in ratio of bone age to chronological age.