Infliximab-dyyb neutralize the biological activity of TNFα by binding with high affinity to the soluble and transmembrane forms of TNFα and inhibit binding of TNFα with its receptors. Infliximab-dyyb has shown biological activities, such as TNFα neutralization activity and TNFα binding affinities, complement 1q (C1q) binding affinity and crystallizable fragment (Fc) receptor binding affinities in a wide variety of in vitro bioasays. The relationship of these biological response markers to the mechanism(s) by which infliximab-dyyb exerts its clinical effects is unknown.

ZYMFENTRA is a tumor necrosis factor (TNF) blocker indicated in adults for maintenance treatment of: 

• moderately to severely active ulcerative colitis following treatment with an infliximab product administered intravenously.
• moderately to severely active Crohn’s disease following with an infliximab products administered intraneously. 

Important Dosage Information.

• ZYMFENTRA is indicated as maintenance treatment only, starting at Week 10 and thereafter.
• All pateitns must complete an intravenous induction regiemen with an infliximab product before starting ZYMFENTRA.
• ZYMFENTRA is for subcutaneous use only.

Recommeneded Maintenance Dosage in Ulcerative Colitis and Crohn's Direase

• Week 10 and thereafter: Inject 120 mg subcutaneously once every two weeks.
• To swift patients who are responding to maintenance therapy with an infliximab product administered intravenously, administer the first subcutaneous dose of ZYMFENTRA in place of the next scheduled intravenous infusion and every two weeks thereafter.
• See the full prescribing information on how to administer subcutaneously.

Most common adverse reactions (>3%) are:

• Ulcerative Colitis: COVID-19, anemia, arthralgia, injection site reaction, increased alanine aminotransferase, and abdominal pain.
• Crohn's Disease: COVID-19, headache, upper respiratory tract infection, injection site reaction, diarrhea, increased blood creatine phosphokinase, arthralgia, increased alanine aminotransferase, hypertension, urinary tract infection, neutropenia, dizziness, and leukopenia.

History of severe hypersentitivity reaction to infliximab-dyyb, other infliximab products, any of the inactive ingredients in ZYMFENTRA or to any murine proteins.

Serious injections, including invasive fungal infections: Avoid use of ZYMFENTRA in patients with an active infection. If infection develops during treatment, conduct a prompt and complete diagnostic workup appropriate for an immunocompromised patient and initiate antimicrobial therapy. If systemic illness develops in patients who reside or travel to regions where mycoses are endemic, consider empiric antifungal therapy.

Malignancies: The incidence of malignancies, including lymphoma, was greater in TNF blocker-treated patients than in controls. Consider the higher risk of hepatosplenic T-cell lymphoma (HSTCL) with combination therapy versus increased tisk of immunogenicity and hypersensitivity reactions with monotherapy. 

Hepatitis B virus (HBV) reactivation: Test for HBV infection before starting ZYMFENTRA. Monitor HBV carriers during and several months after therapy for active HBV infection. If reactivation occurs, stop ZYMFENTRA and begin anti-viral therapy.

Hepatotoxicity: Severe hepatic reactions, some fatal or necessitating liver transplantation with infliximab products. Monitor hepatic enzymes and liver function tests every 3 to 4 months during treatment; investigate liver enzyme elevations and interrupt treatment if drug-induced liver injury is suspected. Instruct patients to seek immediate medical attention if symptoms develop. 

Congestive heart failure (CHF): New onset or worsening symptoms may occur. Avoid ZYMFENTRA in patients with CHF. Monitor for new or worsening symptoms if a decision is made to administer ZYMFENTRA.

Hematologic Reactions: Advise patients to seek immediate medical attention if signs and symtoms of cytopenia develop; consider stopping ZYMFENTRA if significant hematologic abnormalities devlop.

Hypersensitivity and Other Administration Reactions: Serious systemic hypersensitivity reactions including anaphylaxis; institute appropriate therapy and discontinue ZYMFENTRA.

Neurologic Reactions: Exacerbation or new onset CNS demyelinating disorders may occurs; consider discontinuation of ZYMFENTRA.

Risk of infection with concurrent administration of other biological products: Concurrent use with other immunosuppressive biological products may increase the risk of injection

Risk of additive immunosuppressive effects from prior biologic products: Consider the half-life and mode of action of prior biological products. 

Autoimmunity: Formation of autoantibodies and development of lupus-like syndrome may occur; discontinue ZYMFENTRA if symptoms develop.

Vaccinations and Use of Live Vaccines/Therapeutic Infectious Agents: Prior to initiating ZYMFENTRA bring patients up to date with all vaccinations. Live vaccines or therapeutic infectious agents should not be given with ZYMFENTRA. A 6-month waiting period following birth is recommended before the administration of live vaccines to infants exposed in utero to infliximab products.