At a glance
Effects
- Linear growth / height velocity: Stimulates bone elongation and increased annual height velocity in paediatric patients with GHD; demonstrated non-inferiority to daily somatropin (10.1 cm/yr vs 9.8 cm/yr in Phase 3) [2][6].
- IGF-1 elevation: Raises serum IGF-1 and IGF-binding protein-3, the principal downstream biomarkers of GH action, enabling clinical monitoring of response [4][7].
- Metabolic normalisation: Supports normal carbohydrate, lipid, and protein metabolism by replacing deficient endogenous GH signalling [1].
- Reduced injection burden: Reduces injection frequency from daily to once weekly compared to standard somatropin, improving patient adherence and quality of life [3][8].
Long-acting recombinant hGH analog (GH receptor agonist)
NGENLA (Pfizer / OPKO Health)
Subcutaneous injection (once weekly)
0.66 mg/kg/week SC
June 27, 2023 (paediatric GHD, age ≥3 yrs)
About Somatrogon-ghla
Every point here is drawn from public medical and harm-reduction sources. A bracketed number after a claim — like [1]— is a reference: tap it to open the exact source it's based on (numbered list at the bottom). It is not a rating or score. Educational information, not medical advice.
Product specifics
- Est. delivery
- 3–7 business days · EU tracked
Product details as stated by the vendor (claims, not independently verified). Delivery is our standard EU estimate.
What it is
Somatrogon-ghla (brand name NGENLA) is a long-acting, recombinant human growth hormone (hGH) analog approved by the FDA for the treatment of pediatric patients aged 3 years and older who have growth failure due to inadequate secretion of endogenous growth hormone [1][2]. Unlike daily somatropin injections, it is administered once weekly via subcutaneous injection [3].
How it works
Somatrogon-ghla binds to the growth hormone receptor and initiates a signal transduction cascade — specifically activating the STAT5b signalling pathway — which increases serum concentrations of Insulin-like Growth Factor 1 (IGF-1) [1][4]. Elevated GH and IGF-1 together stimulate metabolic changes, linear bone growth, and enhanced growth velocity in paediatric patients with GH deficiency [1]. Its extended duration is achieved by fusing the human GH amino acid sequence with three copies of the carboxy-terminal peptide (CTP) of human chorionic gonadotropin (hCG), which slows clearance and allows once-weekly dosing [5].
Risks & side effects
Most important: Somatrogon-ghla carries a Black Box Warning: increased mortality has been reported in patients with acute critical illness (e.g., open heart or abdominal surgery, multiple trauma, or acute respiratory failure) when treated with somatropin-class agents [9]. Active malignancy is a contraindication, as there is an increased risk of tumour progression with GH-class treatment [9][10].
Common
Serious
- Increased mortality in acute critical illness — BLACK BOX WARNING [9]
- Malignancy progression or recurrence (contraindicated with active cancer) [10]
- Fluid retention / peripheral oedema [11]
- Glucose intolerance / high blood sugar (GH-class drugs reduce insulin sensitivity) [11]
- Intracranial hypertension with papilloedema, visual changes, headache, nausea [10]
- Slipped capital femoral epiphysis (hip/knee pain, limping — requires immediate evaluation) [8]
- Anti-drug antibody development (77% incidence in Phase 3; neutralising antibodies in 3.7%) [7]
- Interference with hCG-based pregnancy tests — possible false positive or false negative results [12]
Rare
- Anaphylaxis / severe hypersensitivity reactions [9]
- Sudden death in Prader-Willi syndrome patients who are severely obese or have sleep apnea [9]
- Progression of pre-existing leukaemia or new neoplasm [10]
- Epiphyseal disorders / abnormal bone development [8]
- Pancreatitis (reported post-approval with somatropin class) [9]
Safety & harm reduction
- Active malignancy — risk of tumour progression [10]
- Acute critical illness (post open heart/abdominal surgery, multiple trauma, acute respiratory failure) — Black Box Warning for increased mortality [9]
- Known hypersensitivity to somatrogon-ghla or any excipient [9][10]
- Closed epiphyses (growth plates fused — no benefit, treatment not indicated) [10]
- Active proliferative or severe non-proliferative diabetic retinopathy [10]
- Prader-Willi syndrome patients who are severely obese, have sleep apnea, or severe respiratory impairment [9]
- IGF-1 serum levels — to assess therapeutic response and avoid excess GH exposure [4]
- Fasting glucose / HbA1c — GH-class agents reduce insulin sensitivity [11]
- Thyroid function (TSH, free T4) — hypothyroidism reported in ≥5% of patients [9]
- Serum phosphorus, alkaline phosphatase, and parathyroid hormone if bone metabolism abnormalities arise [8]
- Ophthalmologic assessment if symptoms of intracranial hypertension develop [10]
- Tumour surveillance / neuroimaging in patients with prior intracranial neoplasms treated with radiation [8]
- Hip/knee assessment (slipped capital femoral epiphysis) if limp or hip/knee pain develops [8]
- Skin surveillance for changes in existing naevi [8]
- Anti-drug antibody testing if growth response is unexpectedly poor [7]
- Oral oestrogens — larger doses of somatrogon-ghla may be required; oral oestrogen impairs GH-stimulated IGF-1 generation [13]
- Insulin and antihyperglycaemic agents — dose adjustment may be required as GH reduces insulin sensitivity [13]
- Glucocorticoids — high-dose or prolonged corticosteroid use inhibits GH response; dose adjustment may be needed [13]
- CYP450-metabolised drugs (e.g., ciclosporin, anticonvulsants, sex steroids) — GH may alter CYP450 enzyme activity; monitor levels [13]
- Must be prescribed and supervised by a healthcare provider experienced in paediatric GHD management [10]
- All preexisting malignancies must be confirmed inactive before initiating treatment [10]
- Inject subcutaneously into abdomen, thigh, or upper arm; rotate sites weekly to minimise local reactions [3]
- Refrigerate at 2–8 °C; once opened, use within 28 days [11]
- If a dose is missed, administer as soon as possible — but must be at least 3 days before the next scheduled dose [3]
Dosage context
The FDA-approved dose for paediatric GHD is 0.66 mg/kg/week administered once weekly by subcutaneous injection [2][6]. This was the dose used throughout the pivotal Phase 3 trial (NCT02968004) across a body weight range of approximately 10–54 kg [2]. Exposure decreases as body weight increases, but the 0.66 mg/kg/week regimen provides adequate systemic exposure across this range [2]. No adult dosing has been established; somatrogon-ghla is not approved for adults. These figures are from the FDA label — not a prescription.
Sources
- 1.WikiDoc – Somatrogon-ghla (FDA label-based)
- 2.Pfizer Medical – NGENLA Clinical Pharmacology
- 3.MedlinePlus – Somatrogon-ghla Injection
- 4.Drugs.com – Somatrogon-ghla Monograph (Professionals)
- 5.Wiley / Clin Pharmacol Drug Dev – Manners et al. 2024 (PK Crossover Study)
- 6.Pfizer Press Release – FDA Approval of NGENLA June 2023
- 7.Pfizer Medical – NGENLA Adverse Reactions
- 8.Drugs.com – Ngenla FDA Approval History
- 9.RxList – Ngenla Side Effects, Warnings, Dosage
- 10.Pfizer Labeling – NGENLA Full Prescribing Information
- 11.WebMD – Ngenla (somatrogon-ghla) Drug Details
- 12.FDA.gov – NGENLA Prescribing Information (2025 label)
- 13.WikiDoc – Somatrogon-ghla Drug Interactions
- 14.FDA Drug Trials Snapshots – NGENLA (link unavailable)
- 15.PMC – Long-acting GH review (NCT02968004 Phase 3 data)
This information is provided for educational and harm-reduction purposes only. It is not medical advice. These substances can carry serious health risks; effects and safe use vary by individual. Consult a qualified healthcare professional before use. Legal status varies by country — it is your responsibility to know your local law. We do not encourage misuse.