Treatment should be initiated and monitored by physicians who are qualified and experienced in the diagnosis and management of paediatric patients with GHD. The amount and concentration of lonapegsomatropin is always expressed in terms of mg somatropin referring to the content of the somatropin moiety and not including mPEG-linker in order to prevent medication errors when patients switch from daily somatropin therapy.
4 Posology The posology and administration should be individualised for each patient. 24 mg somatropin/kg body weight, given once weekly. The recommended starting dose strengths for such a dose by weight range can be found in Table 1.
24 mg somatropin/kg/week, calculate the total weekly dose (in mg somatropin) and select the appropriate dose strength as follows: • Total weekly dose (mg somatropin) = prescribed dose (mg somatropin/kg) x patient’s body weight (kg) • Round the total weekly dose (mg somatropin) to the closest dose strength while also considering treatment goals and clinical response.
Starting dose for patients switching from daily somatropin medicinal products If changing therapy to once-weekly lonapegsomatropin from daily somatropin, there should be at least 8 hours between the final dose of once-daily somatropin and the first dose of lonapegsomatropin.
In children switching from daily somatropin, physicians may adjust the starting dose taking into consideration the current somatropin dose, individual clinical response, and clinical considerations specific to the patient. 24 mg somatropin/kg body weight (Table 1).
24 mg somatropin/kg body weight, use the previously prescribed weekly dose as the recommended starting dose of lonapegsomatropin (see equation above). Dose titration The dose of lonapegsomatropin should be individually adjusted for each patient based on clinical response, adverse reactions, and/or serum insulin-like growth factor-1 (IGF-1) concentrations outside the targeted range.
Available somatropin dose strengths can be found in section 1. 5 Average IGF-1 standard deviation score (SDS) levels (drawn 4-5 days after dosing) can be used as guidance for dose titration (Table 2). It is necessary to wait a minimum of 2 weeks after initiation of lonapegsomatropin or after any dose change before assessing the resulting IGF-1 SDS levels.
e. between -2 and +2 (preferably close to 0 SDS). IGF-1 SDS levels may vary over time, and therefore routine monitoring of serum IGF-1 SDS levels throughout the course of treatment is recommended, especially during puberty. Table 2 Recommended change in somatropin dose strength for average IGF-1 SDS categories Average IGF-1 SDS range (drawn on post-dose day 4-5) Recommended change in somatropin dose strength > +4 Reduce by 3 dose strengths +3 to +4 Reduce by 2 dose strengths +2 to +3 Reduce by 1 dose strength -2 to +2 No change < -2 Increase by 1 dose strength Treatment evaluation Evaluation of efficacy and safety should be considered at approximately 6- to 12-month intervals and may be assessed by evaluating auxological parameters, biochemistry (IGF-1, hormones, glucose, and lipid levels), and pubertal status.
More frequent evaluations should be considered during puberty. Treatment should be discontinued in patients with annualised height velocity < 2 cm/year, final height achievement, height velocity SDS < + 1 after the first year of treatment, or in case bone age is > 14 years (girls) or > 16 years (boys) which corresponds to the closure of the epiphyseal growth plates.
Once the epiphyses are fused, patients should be clinically re-evaluated for the need for growth hormone treatment. 4). Missed dose If a dose is missed, it should be administered as soon as possible and no more than 2 days after the missed dose.
If more than 2 days have passed, the missed dose should be skipped, and the next dose should be administered on the regularly scheduled day. In each case, patients can then resume their regular once-weekly dosing schedule. Changing the dosing day The day of weekly injection can be changed to a different day of the week.
Lonapegsomatropin can be administered 2 days before or 2 days after the scheduled dosing day. It should be ensured that at least 5 days will pass between the last dose and the newly-established regular once-weekly dosing day. Special populations Renal impairment No information in patients with renal impairment is available and dose recommendations cannot be given.
6 Hepatic impairment No information in patients with hepatic impairment is available and dose recommendations cannot be given. Paediatric population The safety and efficacy of lonapegsomatropin in children under 3 years of age has not been established.
1 but no recommendation on a posology can be made. Method of administration Each injection should be administered […]