Version July 2025
Note: Test for tuberculosis (TB) infection (using purified protein derivative [PPD] or IFNγ release assay) and evaluate for TB risk factors prior to emapalumab treatment. Monitor for TB, adenovirus, Epstein-Barr virus, and cytomegalovirus every 2 weeks (and as clinically indicated) during emapalumab treatment. Premedication is recommended (see below). Dosing should be based on actual body weight.
Hemophagocytic lymphohistiocytosis, primary: IV: Initial: 1 mg/kg twice a week (every 3 or 4 days); subsequent doses may be increased based on clinical and laboratory criteria. After the clinical condition is stabilized, decrease dose to the previous level to maintain clinical response. Continue until hematopoietic stem cell transplantation (HSCT) or unacceptable toxicity; discontinue when therapy is no longer required for hemophagocytic lymphohistiocytosis.
Dosage modification:
Treatment day and dose:
Day 1 initial dose: 1 mg/kg
Day 3: May increase to 3 mg/kg if meet criteria for dose increase
Day 6 and beyond: Increase to 6 mg/kg if meet criteria for dose increase
Day 9 and beyond: Increase to 10 mg/kg if (based on initial signs of response) assessment by health care provider indicates that a further increase in emapalumab dose may be of benefit
Criteria for dose increase:
Unsatisfactory improvement in clinical condition (assessed by health care provider) AND at least one of the following:
Fever (persistent or recurrent)
Platelets: Baseline <50,000/mm3 without improvement to >50,000/mm3 or baseline >50,000/mm3 and <30% improvement, or baseline >100,000/mm3 and any decrease to <100,000/mm3
Neutrophils: Baseline <500/mm3 without improvement to >500/mm3 or baseline >500 to 1,000/mm3 and decrease to <500/mm3 or baseline 1,000 to 1,500/mm3 and decrease to <1,000/mm3
Ferritin: Baseline ≥3,000 ng/mL and <20% decrease or baseline <3,000 ng/mL and any increase to >3,000 ng/mL.
Splenomegaly (any worsening)
Coagulopathy (both D-dimer and fibrinogen must apply): D-Dimer: Abnormal at baseline and no improvement; Fibrinogen: Baseline levels ≤100 mg/dL and no improvement or baseline levels >100 mg/dL and any decrease to <100 mg/dL.
Premedication and concomitant therapy: Administer prophylaxis for herpes zoster, pneumocystis jirovecii, and for fungal infections prior to emapalumab administration. Administer tuberculosis (TB) prophylaxis to patients at risk for TB, or known to have a positive PPD test result or a positive IFNγ release assay. For patients not receiving baseline dexamethasone treatment, begin dexamethasone at a dose of at least 5 to 10 mg/m2/day beginning 1 day prior to initiation of emapalumab. For patients receiving baseline dexamethasone, continue the regular dexamethasone dose, as long as the dose is at least 5 mg/m2/day. Dexamethasone may be tapered according to clinical judgement.
Dosage adjustment for concomitant therapy: Significant drug interactions exist, requiring dose/frequency adjustment or avoidance. Consult drug interactions database for more information.
There are no dosage adjustments provided in the manufacturer's labeling; however, renal impairment (including dialysis) had no clinically meaningful effect on emapalumab pharmacokinetics.
There are no dosage adjustments provided in the manufacturer's labeling; however, mild, moderate, or severe hepatic impairment had no clinically meaningful effect on emapalumab pharmacokinetics.
Infusion reaction: If an infusion reaction occurs, interrupt infusion and manage appropriately, then continue with the infusion rate reduced.
Refer to adult dosing.
(For additional information see "Emapalumab: Pediatric drug information")
Note: Tuberculosis screening should be completed prior to emapalumab therapy. Dose should be based on actual body weight.
Hemophagocytic lymphohistiocytosis, primary (HLH): Infants, Children, and Adolescents: IV: Initial dose: 1 mg/kg/dose twice weekly (ie, every 3 to 4 days); subsequent doses may be increased based on clinical and laboratory criteria. After the clinical condition is stabilized, decrease dose to the previous level to maintain clinical response. Continue until hematopoietic stem cell transplantation (HSCT) or unacceptable toxicity; discontinue when therapy is no longer required for HLH.
Dose modification: If inadequate response (see Criteria for dose increase), titrate dose as follows:
Day 3: May increase dose to 3 mg/kg/dose if meets criteria for dose increase
Day 6 and beyond: May increase dose to 6 mg/kg/dose if meets criteria for dose increase
Day 9 and beyond: May increase dose to 10 mg/kg/dose if (based on initial signs of response) assessment by health care provider indicates that a further increase in emapalumab dose may be of benefit.
Criteria for dose increase: Inadequate response as determined by health care provider assessment and at least one of the following criteria:
Fever (persistent or recurrent)
Platelets: Baseline <50,000/mm3 without improvement to >50,000/mm3 or baseline >50,000/mm3 and <30% improvement, or baseline >100,000/mm3 and any decrease to <100,000/mm3
Neutrophils: Baseline <500/mm3 without improvement >500/mm3 or baseline >500 to 1,000/mm3 and decrease to <500/mm3 or baseline 1,000 to 1,500/mm3 and decrease to <1,000/mm3
Ferritin: Baseline ≥3,000 ng/mL and <20% decrease or baseline <3,000 ng/mL and any increase to >3,000 ng/mL
Splenomegaly (any worsening)
Coagulopathy (both D-dimer and fibrinogen criteria must apply): D-Dimer: Abnormal at baseline and no improvement AND Fibrinogen: Baseline levels ≤100 mg/dL and no improvement or baseline levels >100 mg/dL and any decrease to <100 mg/dL
Premedication and concomitant therapy: Administer prophylaxis for herpes zoster, Pneumocystis jirovecii, and for fungal infections prior to emapalumab administration. Administer tuberculosis prophylaxis to patients at risk for tuberculosis or known to have a positive purified protein derivative (PPD) test result or a positive interferon gamma (IFNγ) release assay. If patient is not receiving baseline dexamethasone treatment (≥5 mg/m2/day), begin dexamethasone at a dose of at least 5 to 10 mg/m2/day beginning 1 day prior to initiation of emapalumab. For patients receiving baseline dexamethasone, continue the regular dexamethasone dose, as long as the dose is at least 5 mg/m2/day. Dexamethasone may be tapered according to clinical judgement.
Dosage adjustment for concomitant therapy: Significant drug interactions exist, requiring dose/frequency adjustment or avoidance. Consult drug interactions database for more information.
There are no dosage adjustments provide in the manufacturer's labeling; however, renal impairment (including dialysis) had no clinically meaningful effect on emapalumab pharmacokinetics.
There are no dosage adjustments provide in the manufacturer's labeling; however, hepatic impairment had no clinically meaningful effect on emapalumab pharmacokinetics.
The following adverse drug reactions and incidences are derived from product labeling unless otherwise specified.
>10%:
Cardiovascular: Hypertension (41%), tachycardia (12%)
Central nervous system: Irritability (12%)
Dermatologic: Skin rash (12%)
Endocrine & metabolic: Hypokalemia (15%)
Gastrointestinal: Appendicitis (≤32%), constipation (15%), abdominal pain (12%), diarrhea (12%)
Hematologic & oncologic: Lymphocytosis (12%)
Infection: Infection (56%), viral infection (32% to 41%), bacterial infection (35%), bacteremia (≤32%), histoplasmosis (≤32%), necrotizing fasciitis (≤32%), sepsis (≤32%), cytomegalovirus disease (12%)
Respiratory: Pneumonia (≤32%), cough (12%), tachypnea (12%)
Miscellaneous: Infusion related reaction (27%), fever (24%)
1% to 10%:
Cardiovascular: Bradycardia (<10%), peripheral edema (<10%)
Gastrointestinal: Gastrointestinal hemorrhage (<10%), vomiting (<10%)
Immunologic: Antibody development (3% to 5%)
Infection: Fungal infection (9%)
Neuromuscular & skeletal: Asthenia (<10%)
Renal: Acute renal failure (<10%)
Respiratory: Dyspnea (<10%), epistaxis (<10%)
Miscellaneous: Multi-organ failure (≥3%)
There are no contraindications listed in the manufacturer's labeling.
Concerns related to adverse effects:
• Infection: Infections may commonly occur. Emapalumab may increase the risk of fatal and serious infections including specific pathogens favored by IFNγ neutralization (mycobacteria, herpes zoster virus, and Histoplasma capsulatum); do not administer emapalumab to patients with infections caused by these pathogens until appropriate treatment has been initiated. Serious infections such as pneumonia, bacteremia, sepsis, disseminated histoplasmosis, necrotizing fasciitis, viral infections, and perforated appendicitis were observed in nearly one-third of patients receiving emapalumab in clinical trials. Reported infections were predominantly viral and bacterial, although fungal infections and infections with an unidentified pathogen also occurred. Prior to initiating emapalumab, evaluate for tuberculosis (TB) risk factors and test for TB infection (latent TB) by purified protein derivative (PPD) testing, polymerase chain reaction (PCR), or IFNγ release assay. Administer TB prophylaxis to patients at risk for TB or known to have a positive PPD test result. Prophylaxis for herpes zoster, pneumocystis jirovecii, and fungal infection should also be administered during emapalumab treatment. Utilize surveillance testing during treatment. Monitor closely for signs/symptoms of infection; promptly initiate a complete diagnostic workup appropriate for an immunocompromised patient and initiate appropriate antimicrobial therapy.
• Infusion reactions: Infusion-related reactions (including drug eruption, pyrexia, rash, erythema, and hyperhidrosis) have been reported in over one-fourth of patients treated with emapalumab. Infusion-related reactions occurred during the first infusion in one-third of these patients. Infusion reactions were mild to moderate. Monitor for infusion-related reactions. If an infusion reaction occurs, interrupt infusion and manage appropriately, then continue with the infusion rate reduced.
Concurrent drug therapy issues:
• Immunizations: Do not administer live or live attenuated vaccines to patients receiving emapalumab and for at least 4 weeks following the last emapalumab dose (safety of immunization with live vaccines during or following emapalumab has not been studied).
Dosage form specific issues:
• Polysorbate 80: Some dosage forms may contain polysorbate 80 (also known as Tweens). Hypersensitivity reactions, usually a delayed reaction, have been reported following exposure to pharmaceutical products containing polysorbate 80 in certain individuals (Isaksson 2002; Lucente 2000; Shelley 1995). Thrombocytopenia, ascites, pulmonary deterioration, and renal and hepatic failure have been reported in premature neonates after receiving parenteral products containing polysorbate 80 (Alade 1986; CDC 1984). See manufacturer's labeling.
Excipient information presented when available (limited, particularly for generics); consult specific product labeling.
Solution, Intravenous [preservative free]:
Gamifant: Emapalumab-lzsg 10 mg/2 mL (2 mL); Emapalumab-lzsg 50 mg/10 mL (10 mL); Emapalumab-lzsg 100 mg/20 mL (20 mL) [contains polysorbate 80]
No
Solution (Gamifant Intravenous)
10 mg/2 mL (per mL): $2,178.96
50 mg/10 mL (per mL): $2,178.96
100 mg/20 mL (per mL): $2,178.96
Disclaimer: A representative AWP (Average Wholesale Price) price or price range is provided as reference price only. A range is provided when more than one manufacturer's AWP price is available and uses the low and high price reported by the manufacturers to determine the range. The pricing data should be used for benchmarking purposes only, and as such should not be used alone to set or adjudicate any prices for reimbursement or purchasing functions or considered to be an exact price for a single product and/or manufacturer. Medi-Span expressly disclaims all warranties of any kind or nature, whether express or implied, and assumes no liability with respect to accuracy of price or price range data published in its solutions. In no event shall Medi-Span be liable for special, indirect, incidental, or consequential damages arising from use of price or price range data. Pricing data is updated monthly.
IV: Infuse over 1 hour through an IV line containing a sterile, non-pyrogenic, low-protein binding 0.2 micron inline filter. Do not shake. Allow solution to reach room temperature prior to infusion. Do not infuse with other medications. If an infusion reaction occurs, interrupt infusion and manage appropriately, then continue with the infusion rate reduced.
Parenteral: IV: If diluted solution was refrigerated, allow solution to come to room temperature prior to administration. Do not shake. Administer over 1 hour through a sterile, non-pyrogenic 0.2-micron low-protein-binding filter. Do not infuse with other medications.
Rate adjustment for infusion-related reactions: Interrupt infusion and manage appropriately, then continue with the slower infusion rate.
Primary hemophagocytic lymphohistiocytosis: Treatment of primary hemophagocytic lymphohistiocytosis (HLH) in adult and pediatric (newborn and older) patients with refractory, recurrent or progressive disease or intolerance to conventional HLH therapy.
Emapalumab may be confused with avelumab, durvalumab, eculizumab, elotuzumab, emicizumab.
Gamifant may be confused with GamaSTAN.
None known.
Note: Interacting drugs may not be individually listed below if they are part of a group interaction (eg, individual drugs within “CYP3A4 Inducers [Strong]” are NOT listed). For a complete list of drug interactions by individual drug name and detailed management recommendations, use the drug interactions program by clicking on the “Launch drug interactions program” link above.
Abrocitinib: May increase immunosuppressive effects of Immunosuppressants (Therapeutic Immunosuppressant Agents). Risk X: Avoid
Androgens: Hypertension-Associated Agents may increase hypertensive effects of Androgens. Risk C: Monitor
Antithymocyte Globulin (Equine): Immunosuppressants (Therapeutic Immunosuppressant Agents) may increase adverse/toxic effects of Antithymocyte Globulin (Equine). Specifically, these effects may be unmasked if the dose of immunosuppressive therapy is reduced. Immunosuppressants (Therapeutic Immunosuppressant Agents) may increase immunosuppressive effects of Antithymocyte Globulin (Equine). Specifically, infections may occur with greater severity and/or atypical presentations. Risk C: Monitor
Baricitinib: Immunosuppressants (Therapeutic Immunosuppressant Agents) may increase immunosuppressive effects of Baricitinib. Risk X: Avoid
BCG Products: Immunosuppressants (Therapeutic Immunosuppressant Agents) may decrease therapeutic effects of BCG Products. Immunosuppressants (Therapeutic Immunosuppressant Agents) may increase adverse/toxic effects of BCG Products. Specifically, the risk of vaccine-associated infection may be increased. Risk X: Avoid
Brincidofovir: Immunosuppressants (Therapeutic Immunosuppressant Agents) may decrease therapeutic effects of Brincidofovir. Risk C: Monitor
Brivudine: May increase adverse/toxic effects of Immunosuppressants (Therapeutic Immunosuppressant Agents). Risk X: Avoid
Chikungunya Vaccine (Live): Immunosuppressants (Therapeutic Immunosuppressant Agents) may increase adverse/toxic effects of Chikungunya Vaccine (Live). Specifically, the risk of vaccine-associated infection may be increased. Immunosuppressants (Therapeutic Immunosuppressant Agents) may decrease therapeutic effects of Chikungunya Vaccine (Live). Risk X: Avoid
Cladribine: Immunosuppressants (Therapeutic Immunosuppressant Agents) may increase immunosuppressive effects of Cladribine. Risk X: Avoid
Coccidioides immitis Skin Test: Coadministration of Immunosuppressants (Therapeutic Immunosuppressant Agents) and Coccidioides immitis Skin Test may alter diagnostic results. Management: Consider discontinuing therapeutic immunosuppressants several weeks prior to coccidioides immitis skin antigen testing to increase the likelihood of accurate diagnostic results. Risk D: Consider Therapy Modification
COVID-19 Vaccine (Inactivated Virus): Immunosuppressants (Therapeutic Immunosuppressant Agents) may decrease therapeutic effects of COVID-19 Vaccine (Inactivated Virus). Risk C: Monitor
COVID-19 Vaccine (mRNA): Immunosuppressants (Therapeutic Immunosuppressant Agents) may decrease therapeutic effects of COVID-19 Vaccine (mRNA). Management: Give a 3-dose primary series for all patients aged 6 months and older taking immunosuppressive medications or therapies. Booster doses are recommended for certain age groups. See CDC guidance for details. Risk D: Consider Therapy Modification
COVID-19 Vaccine (Subunit): Immunosuppressants (Therapeutic Immunosuppressant Agents) may decrease therapeutic effects of COVID-19 Vaccine (Subunit). Risk C: Monitor
Dengue Tetravalent Vaccine (Live): Immunosuppressants (Therapeutic Immunosuppressant Agents) may decrease therapeutic effects of Dengue Tetravalent Vaccine (Live). Immunosuppressants (Therapeutic Immunosuppressant Agents) may increase adverse/toxic effects of Dengue Tetravalent Vaccine (Live). Specifically, the risk of vaccine-associated infection may be increased. Risk X: Avoid
Denosumab: Immunosuppressants (Therapeutic Immunosuppressant Agents) may increase immunosuppressive effects of Denosumab. Management: Consider the risk of serious infections versus the potential benefits of coadministration of denosumab and immunosuppressants. If combined, monitor for signs/symptoms of serious infections. Risk D: Consider Therapy Modification
Deucravacitinib: May increase immunosuppressive effects of Immunosuppressants (Therapeutic Immunosuppressant Agents). Risk X: Avoid
Efgartigimod Alfa: May decrease therapeutic effects of Fc Receptor-Binding Agents. Risk C: Monitor
Etrasimod: May increase immunosuppressive effects of Immunosuppressants (Therapeutic Immunosuppressant Agents). Risk X: Avoid
Filgotinib: May increase immunosuppressive effects of Immunosuppressants (Therapeutic Immunosuppressant Agents). Risk X: Avoid
Inebilizumab: Immunosuppressants (Therapeutic Immunosuppressant Agents) may increase immunosuppressive effects of Inebilizumab. Risk C: Monitor
Influenza Virus Vaccines: Immunosuppressants (Therapeutic Immunosuppressant Agents) may decrease therapeutic effects of Influenza Virus Vaccines. Management: Administer influenza vaccines at least 2 weeks prior to initiating immunosuppressants if possible. If vaccination occurs less than 2 weeks prior to or during therapy, revaccinate 2 to 3 months after therapy discontinued if immune competence restored. Risk D: Consider Therapy Modification
Leflunomide: Immunosuppressants (Therapeutic Immunosuppressant Agents) may increase immunosuppressive effects of Leflunomide. Management: Increase the frequency of chronic monitoring of platelet, white blood cell count, and hemoglobin or hematocrit to monthly, instead of every 6 to 8 weeks, if leflunomide is coadministered with immunosuppressive agents. Risk D: Consider Therapy Modification
Mumps- Rubella- or Varicella-Containing Live Vaccines: Immunosuppressants (Therapeutic Immunosuppressant Agents) may decrease therapeutic effects of Mumps- Rubella- or Varicella-Containing Live Vaccines. Immunosuppressants (Therapeutic Immunosuppressant Agents) may increase adverse/toxic effects of Mumps- Rubella- or Varicella-Containing Live Vaccines. Specifically, the risk of vaccine-associated infection may be increased. Risk X: Avoid
Nadofaragene Firadenovec: Immunosuppressants (Therapeutic Immunosuppressant Agents) may increase adverse/toxic effects of Nadofaragene Firadenovec. Specifically, the risk of disseminated adenovirus infection may be increased. Risk X: Avoid
Natalizumab: Immunosuppressants (Therapeutic Immunosuppressant Agents) may increase immunosuppressive effects of Natalizumab. Risk X: Avoid
Nipocalimab: May decrease therapeutic effects of Fc Receptor-Binding Agents. Risk C: Monitor
Ocrelizumab: Immunosuppressants (Therapeutic Immunosuppressant Agents) may increase immunosuppressive effects of Ocrelizumab. Risk C: Monitor
Ofatumumab: Immunosuppressants (Therapeutic Immunosuppressant Agents) may increase immunosuppressive effects of Ofatumumab. Risk C: Monitor
Pidotimod: Immunosuppressants (Therapeutic Immunosuppressant Agents) may decrease therapeutic effects of Pidotimod. Risk C: Monitor
Pimecrolimus: Immunosuppressants (Therapeutic Immunosuppressant Agents) may increase immunosuppressive effects of Pimecrolimus. Risk X: Avoid
Pneumococcal Vaccines: Immunosuppressants (Therapeutic Immunosuppressant Agents) may decrease therapeutic effects of Pneumococcal Vaccines. Risk C: Monitor
Poliovirus Vaccine (Live/Trivalent/Oral): Immunosuppressants (Therapeutic Immunosuppressant Agents) may decrease therapeutic effects of Poliovirus Vaccine (Live/Trivalent/Oral). Immunosuppressants (Therapeutic Immunosuppressant Agents) may increase adverse/toxic effects of Poliovirus Vaccine (Live/Trivalent/Oral). Specifically, the risk of vaccine-associated infection may be increased. Risk X: Avoid
Polymethylmethacrylate: Immunosuppressants (Therapeutic Immunosuppressant Agents) may increase hypersensitivity effects of Polymethylmethacrylate. Management: Use caution when considering use of bovine collagen-containing implants such as the polymethylmethacrylate-based Bellafill brand implant in patients who are receiving immunosuppressants. Consider use of additional skin tests prior to administration. Risk D: Consider Therapy Modification
Rabies Vaccine: Immunosuppressants (Therapeutic Immunosuppressant Agents) may decrease therapeutic effects of Rabies Vaccine. Management: Complete rabies vaccination at least 2 weeks before initiation of immunosuppressant therapy if possible. If combined, check for rabies antibody titers, and if vaccination is for post exposure prophylaxis, administer a 5th dose of the vaccine. Risk D: Consider Therapy Modification
Ritlecitinib: Immunosuppressants (Therapeutic Immunosuppressant Agents) may increase immunosuppressive effects of Ritlecitinib. Risk X: Avoid
Rozanolixizumab: May decrease therapeutic effects of Fc Receptor-Binding Agents. Risk C: Monitor
Ruxolitinib (Topical): Immunosuppressants (Therapeutic Immunosuppressant Agents) may increase immunosuppressive effects of Ruxolitinib (Topical). Risk X: Avoid
Sipuleucel-T: Immunosuppressants (Therapeutic Immunosuppressant Agents) may decrease therapeutic effects of Sipuleucel-T. Management: Consider reducing the dose or discontinuing the use of immunosuppressants prior to initiating sipuleucel-T therapy. Risk D: Consider Therapy Modification
Solriamfetol: May increase hypertensive effects of Hypertension-Associated Agents. Risk C: Monitor
Sphingosine 1-Phosphate (S1P) Receptor Modulators: May increase immunosuppressive effects of Immunosuppressants (Therapeutic Immunosuppressant Agents). Risk C: Monitor
Tacrolimus (Topical): Immunosuppressants (Therapeutic Immunosuppressant Agents) may increase immunosuppressive effects of Tacrolimus (Topical). Risk X: Avoid
Talimogene Laherparepvec: Immunosuppressants (Therapeutic Immunosuppressant Agents) may increase adverse/toxic effects of Talimogene Laherparepvec. Specifically, the risk of infection from the live, attenuated herpes simplex virus contained in talimogene laherparepvec may be increased. Risk X: Avoid
Tertomotide: Immunosuppressants (Therapeutic Immunosuppressant Agents) may decrease therapeutic effects of Tertomotide. Risk X: Avoid
Tofacitinib: Immunosuppressants (Therapeutic Immunosuppressant Agents) may increase immunosuppressive effects of Tofacitinib. Management: Coadministration of tofacitinib with potent immunosuppressants is not recommended. Use with non-biologic disease-modifying antirheumatic drugs (DMARDs) was permitted in psoriatic arthritis clinical trials. Risk X: Avoid
Typhoid Vaccine: Immunosuppressants (Therapeutic Immunosuppressant Agents) may decrease therapeutic effects of Typhoid Vaccine. Immunosuppressants (Therapeutic Immunosuppressant Agents) may increase adverse/toxic effects of Typhoid Vaccine. Specifically, the risk of vaccine-associated infection may be increased. Risk X: Avoid
Ublituximab: Immunosuppressants (Therapeutic Immunosuppressant Agents) may increase immunosuppressive effects of Ublituximab. Risk C: Monitor
Upadacitinib: Immunosuppressants (Therapeutic Immunosuppressant Agents) may increase immunosuppressive effects of Upadacitinib. Risk X: Avoid
Vaccines (Live): Immunosuppressants (Therapeutic Immunosuppressant Agents) may decrease therapeutic effects of Vaccines (Live). Immunosuppressants (Therapeutic Immunosuppressant Agents) may increase adverse/toxic effects of Vaccines (Live). Specifically, the risk of vaccine-associated infection may be increased. Risk X: Avoid
Vaccines (Non-Live/Inactivated/Non-Replicating): Immunosuppressants (Therapeutic Immunosuppressant Agents) may decrease therapeutic effects of Vaccines (Non-Live/Inactivated/Non-Replicating). Management: Give non-live/inactivated/non-replicating vaccines at least 2 weeks prior to starting immunosuppressants when possible. Patients vaccinated less than 14 days before or during therapy should be revaccinated at least 2 to 3 months after therapy is complete. Risk D: Consider Therapy Modification
Yellow Fever Vaccine: Immunosuppressants (Therapeutic Immunosuppressant Agents) may decrease therapeutic effects of Yellow Fever Vaccine. Immunosuppressants (Therapeutic Immunosuppressant Agents) may increase adverse/toxic effects of Yellow Fever Vaccine. Specifically, the risk of vaccine-associated infection may be increased. Risk X: Avoid
Zoster Vaccine (Live/Attenuated): Immunosuppressants (Therapeutic Immunosuppressant Agents) may increase adverse/toxic effects of Zoster Vaccine (Live/Attenuated). Specifically, the risk of vaccine-associated infection may be increased. Immunosuppressants (Therapeutic Immunosuppressant Agents) may decrease therapeutic effects of Zoster Vaccine (Live/Attenuated). Risk X: Avoid
Adverse events were not observed in animal reproduction studies.
It is not known if emapalumab is present in breast milk.
According to the manufacturer, the decision to breastfeed during therapy should consider the risk of infant exposure, the benefits of breastfeeding to the infant, and benefits of treatment to the mother.
Monitor for clinical improvement based on platelet counts, neutrophil counts, ferritin, D-dimer and fibrinogen, fever, and signs/symptoms of splenomegaly.
Prior to initiating emapalumab, evaluate for tuberculosis (TB) risk factors and test for infection (latent TB) by purified protein derivative (PPD) testing, PCR, or IFNγ release assay. Monitor for TB, adenovirus, Epstein-Barr virus, and cytomegalovirus every 2 weeks (and as clinically indicated) during emapalumab treatment. Surveillance testing for herpes zoster, pneumocystis jirovecii, and fungal infection should be utilized during treatment.
Monitor closely for signs/symptoms of infection; promptly initiate a complete diagnostic workup appropriate for an immunocompromised patient. Monitor for infusion-related reactions.
Emapalumab is an interferon gamma (IFNγ) blocking monoclonal antibody. IFNγ is hypersecreted in hemophagocytic lymphohistiocytosis (HLH); emapalumab binds to IFNγ and neutralizes it.
Distribution: Vd (based on a 70 kg patient): Central: 4.2 L; Peripheral: 5.6 L
Metabolism: Emapalumab is likely degraded into small peptides and amino acids via catabolic pathways.
Half-life elimination: Healthy subjects: ~22 days; Patients with hemophagocytic lymphohistiocytosis (HLH): 2.5 to 18.9 days
Body weight: Body weight (2 to 82 kg) was a significant covariate of emapalumab pharmacokinetics (therefore supporting body weight-based dosing).
