Fensolvi® demonstrated sustained suppression of luteinizing hormone (LH) level to <4 IU/L. 
Fensolvi® demonstrated suppression of reproductive hormones to prepubertal levels. 
Effectively impacted clinical sign of pubertal progression. 
Fensolvi delivers an effective and safe therapy for patients with central precocious puberty, with benefits of subcutaneous administration and twice-yearly dosing. 
The efficacy of Fensolvi was evaluated in an uncontrolled, open-label single arm clinical trial in which 64 pediatric patients (62 females and 2 males), with central precocious puberty received at least one dose of Fensolvi at a dosing interval of 24 weeks, and were observed for 12 months. 
The mean age was 7.5 years (range 4-9 years) at the start of treatment
Subjects in the safety data set included: 53% White; 23% Black; 8% American Indian or Alaska Native; 5% Asian; and 2% Native Hawaiian or Other Pacific Islander. Additionally, 56% of the subjects self-identified as Hispanic or Latino ethnicity 
There was a transient surge in circulating levels of LH, FSH, estradiol and testosterone following the first administration. A decrease in basal and LH and FSH levels along with reductions in estradiol and testosterone were observed within several weeks and after repeat administration of Fensolvi.  Suppression of stimulated luteinizing hormone concentrations to <4 IU/L was achieved in 87% of subjects at month 6 and in 85% of patients at month 3, 9, and 12 (See Table 3). 
Table 2. Reproductive hormone levels (Mean ± SD) in children* post GnRH stimulation test
Table 3. % of children* achieving important endpoints in reproductive hormone levels post GnRH stimulation test
Eight female patients out of 62 did not meet the primary efficacy criteria for LH <4 IU/L at 6 months.
In four of the eight patients, the LH level at 6 months was between 4.2 and 4.8 IU/L. The remaining four patients had LH levels >5 IU/L. 
Post stimulation estradiol was suppressed to prepubertal levels (<20 pg/mL) in seven of the eight patients at month 6 and was maintained through month 12. 
Fensolvi suppressed LH to < 4 IU/L post GnRH stimulation test in at least 85% of subjects, and estradiol and testosterone were suppressed to prepubertal levels in 97% of subjects. Progression of growth velocity was successfully arrested or reversed in majority of patients (57/59) by Tanner staging. 
Predicted adult height in untreated patients may be reduced by up to 13.7 cm and 8.3 cm in boys and girls, respectively. 
Fensolvi reduced height velocity (Figure 6). After initiation of therapy, mean height velocity decreased steadily at each time point: Mean height velocity decreased to near normal prepubertal rates from week 4 to week 48, from 8.9 cm/year to 6.4 cm/year.  Treatment reduced mean height velocity to near prepubertal levels.
Figure 6. Mean height velocity through 48 weeks of treatment
The progression of clinical signs of puberty was arrested or reversed in 57/59 patients (97%) at month 6.
- Regression in pubertal stage for breast development was observed in 46% (26/57) of girls by week 48, and stabilization of breast stage was seen in another 51% (29/57).
- At the week 48 assessment, both boys regressed from Tanner 3 to Tanner 2 for external genitalia development (Figure 7). 
Figure 7. Regression or stabilization of Tanner staging* during treatment
- FENSOLVI® (leuprolide acetate) for injectable suspension 45 mg Prescribing Information. Dublin 2, Ireland: Tolmar International, Ltd.; 04/2020.
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