Logo

OpiCalc

FavoritesSpecialtiesDrugsGuidelinesMost Used

All Specialties

OpiCalc Logo
FavoritesSpecialtiesDrugsGuidelinesMost Used
FavesSpecsDrugsGuidesTop
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
OpiCalc Logo

OpiCalc

Easy, fast, and private medical tools for clinicians. Always free.

No Login Required
Ready for the Bedside

Resources

About UsEditorial PolicyMedical DisclaimerPrivacy PolicyTerms of UseCookie Policy

Support

Contact Us

Clinical Notice:OpiCalc is not a substitute for professional clinical judgment. Always verify dosages and guidelines.

OpiCalc © 2018-2026

•

All Rights Reserved

Registry Hub
Erythropoiesis-Stimulating Agent/Discontinued

OMONTYS

OMONTYS

Clinical safety rating

caution

Comprehensive clinical and safety monograph for OMONTYS (OMONTYS).


Mechanism of Action

Erythropoiesis-stimulating agent; synthetic peptide agonist of the erythropoietin receptor (EPOR) that stimulates erythropoiesis in red blood cell precursors.

What the body does with it

MetabolismNot metabolized by cytochrome P450 enzymes; degraded into small peptides and amino acids via catabolic pathways.
ExcretionPrimarily eliminated via the reticuloendothelial system; no significant renal or biliary excretion. The iron component is incorporated into hemoglobin or stored as ferritin/hemosiderin.
Half-lifeTerminal elimination half-life is approximately 14.5 hours in healthy adults; in hemodialysis patients, half-life is extended to 26.4–29.9 hours, supporting weekly dosing.
Protein bindingFerric pyrophosphate citrate moiety: <5% bound to plasma proteins; iron is rapidly transferred to transferrin.
Volume of DistributionVd approximately 0.47 L/kg (range 0.2–0.8 L/kg), indicating distribution primarily into plasma and interstitial fluid; iron distributes to bone marrow and reticuloendothelial system.
BioavailabilityNot applicable; OMONTYS is administered only intravenously. Oral bioavailability is not relevant.
Onset of ActionIntravenous administration: hemoglobin rise observed within 1–2 weeks; reticulocyte count increase within 7–10 days.
Duration of ActionHemoglobin levels maintained for up to 4 weeks following a single IV dose; weekly dosing regimen sustains correction of iron deficiency anemia in hemodialysis patients.
Molecular Weight45000

Classification & Brands

Dosing & administration

45 mg subcutaneously once every 4 weeks (monthly) in adults.

Dosage formSOLUTION
Renal impairmentNo dosage adjustment required for any degree of renal impairment, including end-stage renal disease.
Liver impairmentNo dosage adjustment recommended for mild or moderate hepatic impairment (Child-Pugh A or B). Not studied in severe hepatic impairment (Child-Pugh C).
Pediatric useSafety and efficacy in pediatric patients have not been established; no recommended dose.
Geriatric useNo specific dosage adjustment needed; consider age-related renal function and individual tolerability.

Use during pregnancy

1st trimesterLimited human data. Animal studies show embryo-fetal toxicity. Use only if benefit outweighs risk.
2nd trimesterLimited human data. Based on mechanism, potential for fetal harm. Monitor for maternal hypertension and thrombotic events.
3rd trimesterLimited human data. Use only if clearly needed. May increase risk of thrombotic events and hypertension.

Clinical note

Comprehensive clinical and safety monograph for OMONTYS (OMONTYS).

Placental transferBased on molecular weight and animal studies, omontys is expected to cross the placenta. Embryo-fetal toxicity observed in animal studies.
BreastfeedingIt is unknown if omontys is excreted in human milk. Because of the potential for adverse reactions in the breastfed infant, breast-feeding is not recommended during treatment and for at least 2 weeks after the last dose.
Lactation RatingL5
Teratogenic RiskOMONTYS (pegcetacoplan) is a complement inhibitor. There are no adequate and well-controlled studies in pregnant women. In animal reproduction studies, no adverse developmental effects were observed at maternal exposures up to 20 times the human exposure at the recommended clinical dose. Based on its mechanism of action as a complement inhibitor, there is a theoretical risk of increased susceptibility to infections for the fetus, but no specific teratogenic effects have been identified. The drug should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus.
Fetal MonitoringMonitor for signs and symptoms of infection, including encapsulated bacteria (e.g., Neisseria meningitidis, Streptococcus pneumoniae, Haemophilus influenzae). Fetal monitoring with standard prenatal care (ultrasound, fetal growth assessment) is recommended. Ensure appropriate vaccination status (e.g., meningococcal vaccine) prior to conception if possible. Monitor maternal complement activity and complete blood count (CBC) as per usual clinical practice. No specific fetal monitoring beyond routine obstetric care is indicated.
Fertility EffectsThere are no human data on the effect of pegcetacoplan on fertility. In animal studies, no adverse effects on male or female fertility were observed at exposures up to 20 times the human exposure. The drug is not expected to impair fertility based on its mechanism of action, but these data are limited.

Warnings & precautions

■ FDA Black Box Warning

Increased risk of serious cardiovascular events, myocardial infarction, stroke, venous thromboembolism, vascular access thrombosis, and mortality when targeting hemoglobin levels >11 g/dL; increased risk of tumor progression and recurrence in patients with cancer; not indicated for treatment of anemia in cancer patients due to increased risk of death and serious cardiovascular events.

Side Effect Profile

Serious Effects

Absolute Contraindications

Hypersensitivity to omontys or any component of the formulationUncontrolled hypertension

Clinical Precautions

PrecautionsIncreased mortality, serious cardiovascular events, and thromboembolic events; hypertension; seizures; pure red cell aplasia (PRCA) with neutralizing antibodies; increased risk of tumor progression in cancer patients; hemoglobin monitoring; iron deficiency management; hypersensitivity reactions including anaphylaxis.
Food/DietaryNo clinically significant food interactions reported. Administer subcutaneously, independent of meals.

Clinical Tips & Counseling

Clinical PearlsOMONTYS (pegcetacoplan) is a C3 inhibitor approved for paroxysmal nocturnal hemoglobinuria (PNH). Initiate only in patients vaccinated against encapsulated bacteria (Neisseria meningitidis, Streptococcus pneumoniae, Haemophilus influenzae type b) due to increased infection risk. Monitor for hemolysis, thrombosis, and breakthrough disease; consider dose adjustments if hemoglobin drops significantly. Do not discontinue abruptly—switch to alternative therapy under medical supervision.
Patient AdviceYou must receive vaccinations against meningococcus, pneumococcus, and Haemophilus influenzae type b before starting OMONTYS and maintain up-to-date immunizations. · Report any signs of infection immediately: fever, headache with stiff neck, confusion, chills, or rash. · Do not stop taking OMONTYS without talking to your doctor—sudden discontinuation may cause serious hemolysis. · You may experience injection site reactions; rotate injection sites and avoid injecting into tender or scarred areas. · Store OMONTYS in the refrigerator at 2°C to 8°C (36°F to 46°F). Do not freeze or shake. Protect from light.

OMONTYS Interactions

Loading safety data…

This overview is compiled from peer-reviewed clinical sources and FDA labeling. It's here to support — not replace — clinical judgment. Always verify dosing against your institution's current protocols before prescribing.

On this page

Mechanism of ActionDosing & administrationUse during pregnancyWarnings & precautionsDrug interactions

Compare with

ARANESPEPOGEN/PROCRITMIRCERAOMONTYS PRESERVATIVE FREERETACRIT

External sources

DailyMed (NIH) PubMed OpenFDA