Bizengri

Bizengri is used to treat certain types of non-small cell lung cancer (NSCLC), pancreatic adenocarcinoma, and cholangiocarcinoma in adults. It is given by intravenous infusion every 2 weeks

Bizengri (zenocutuzumab-zbco) works by binding to HER2 (Human epidermal growth factor receptor-2) and HER3, which are proteins that play a key role in the growth of certain cancers. Bizengri's mechanism of action utilizes the Merus Dock & Block mechanism to first dock onto HER2, then block HER3’s ability to bind NRG1 (Neuregulin 1 – a protein-coding gene). Bizengri belongs to the drug class called bispecific HER2- and HER3-directed antibodies.

Bizengri (zenocutuzumab) gained FDA approval for NSCLC and pancreatic adenocarcinoma on December 4, 2024, under the accelerated approval designation, which is contingent upon continued benefits being shown in confirmatory clinical trials. Full approval for cholangiocarcinoma was granted on May 6, 2026.

Bizengri is FDA-approved to treat adults with:

• Lung cancer, called non-small cell lung cancer (NSCLC): that has a neuregulin 1 (NRG1) gene fusion and cannot be removed by surgery or has spread to other parts of the body (advanced unresectable or metastatic), and whose disease has worsened on or after prior cancer treatment.
• Pancreatic cancer, called pancreatic adenocarcinoma: that has a neuregulin 1 (NRG1) gene fusion and cannot be removed by surgery or has spread to other parts of the body (advanced unresectable or metastatic), and whose disease has worsened on or after prior cancer treatment.
• Bile duct cancer, called cholangiocarcinoma: that has a neuregulin 1 (NRG1) gene fusion and cannot be removed by surgery or has spread to other parts of the body (advanced unresectable or metastatic), and whose disease has worsened on or after prior cancer treatment.

It is not known if Bizengri is safe and effective in children.

No, Bizengri (zenocutuzumab-zbco) is not chemotherapy; it is a targeted therapy. Unlike chemotherapy, which broadly targets rapidly dividing cells, Bizengri works by precisely blocking tumor-promoting signals at the HER2/HER3 receptor level.

• Bizengri will be given to you by your healthcare provider as an intravenous (IV) infusion (an infusion into your vein), usually over 4 hours.
• Bizengri is usually given 1 time every 2 weeks.
• Your healthcare provider will decide how many treatments you will need.

Bizengri carries a Boxed Warning for embryo-fetal toxicity (harm to an unborn baby).

Exposure to Bizengri during pregnancy can harm an unborn baby

If you are a woman with childbearing potential, your healthcare provider may do a pregnancy test before you start treatment with Bizengri. Use effective birth control (contraception) during treatment and for 2 months after your last dose of Bizengri. Tell your healthcare provider right away if you become pregnant or think you might be pregnant during treatment with Bizengri.

Bizengri can cause the following serious side effects:

• Infusion-related reactions, allergic (hypersensitivity), and anaphylactic reactions. Bizengri can cause serious infusion-related and allergic reactions that can be life-threatening. Infusion-related reactions are also common during Bizengri treatment. Before each Bizengri infusion, your healthcare provider will give you medicines to help reduce your chance of getting infusion-related reactions. Your healthcare provider will monitor you for signs and symptoms during your infusion and for at least 1 hour after your first infusion and as needed. Tell your healthcare provider right away if you develop any of the following signs or symptoms during or after your Bizengri infusion: chills or shaking itching or rash nausea, vomiting, or diarrhea shortness of breath or wheezing fever chest discomfort cough feeling light-headed sudden swelling of your face, tongue, dizziness throat, or troubled swallowing back or neck pain throat tightness or discomfort feeling of numbness or tingling.
• Lung problems (interstitial lung disease/pneumonitis). Bizengri can cause serious lung problems that may be life-threatening. If you develop lung problems, your healthcare provider may treat you with corticosteroid medicines. Tell your healthcare provider right away if you develop any new or worsening symptoms of lung problems, including: trouble breathing cough shortness of breath fever.
• Heart problems that may affect your heart’s ability to pump blood: Bizengri can cause serious and life-threatening heart problems that may lead to death. Your healthcare provider will check your heart function before you start treatment with BizengriI and as needed during your treatment. Tell your healthcare provider right away if you develop any new or worsening symptoms of heart problems, including shortness of breath, coughing, tiredness, swelling of your feet, ankles, or legs, irregular heartbeat, sudden weight gain, dizziness or feeling light-headed, loss of consciousness.

Your healthcare provider will check you for these side effects during your treatment with Bizengri and may delay your treatment, slow the infusion rate, or completely stop your treatment with Bizengri if you develop severe side effects.

Harm to your unborn baby

Tell your healthcare provider right away if you become pregnant or think you might be pregnant during treatment with Bizengri. Females who can become pregnant:

• Your healthcare provider will do a pregnancy test before you start treatment with Bizengri
• Use effective birth control (contraception) during treatment and for 2 months after your last dose of Bizengri.

These are not all of the possible side effects of Bizengri. Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.

Before receiving Bizengri, tell your healthcare provider about all your medical conditions, including if you:

• Have lung or breathing problems other than your lung cancer
• Have or have had any heart problems
• are pregnant or planning to become pregnant
• are breastfeeding or plan to breastfeed. It is not known if Bizengri passes into your breast milk. Do not breastfeed during treatment and for 2 months after your last dose of Bizengri.

Tell your healthcare provider about all the medicines you take, including prescription and over-the-counter medicines, vitamins, and herbal supplements.

Pregnancy

Bizengri can seriously harm an unborn baby, and you should not be pregnant when starting treatment. Tell your healthcare provider right away if you become pregnant or think you might be pregnant during treatment with Bizengri. Females who can become pregnant:

• Your healthcare provider will do a pregnancy test before you start treatment with Bizengri
• Use effective birth control (contraception) during treatment and for 2 months after your last dose of Bizengri.

Common Side Effects

The most common side effects of Bizengri are:

• diarrhea
• muscle or bone pain
• fatigue
• nausea
• infusion-related reactions
• shortness of breath (dyspnea)
• rash
• Vomiting
• abdominal pain
• edema.

The most common Grade 3 or 4 laboratory abnormalities are:

• increased liver enzymes (such as GGT, AST, ALT)
• increased alkaline phosphatase
• decreased hemoglobin and platelets
• decreased sodium, magnesium, and phosphate levels
• increased aPTT and bilirubin.

Recommended Dose of Bizengri for NSCLC, pancreatic adenocarcinoma, or cholangiocarcinoma

• 750 mg intravenously every 2 weeks until disease progression or unacceptable toxicity.
• Usually given over 4 hours.

The following premedications are recommended to be given before each Bizengri infusion to reduce the risk of infusion-related reactions:

• Corticosteroid: dexamethasone 10 mg either orally or intravenously (for the first infusion and then optional)
• Antipyretic: acetaminophen 1,000 mg either orally or intravenously
• H1 antihistamine: dexchlorpheniramine 5 mg (or another anti-H1 equivalent), either orally or intravenously.

Tell your healthcare provider about all your medicines, including prescription and over-the-counter medicines, vitamins, and herbal supplements.

Active ingredient: zenocutuzumab-zbco

Inactive ingredients: histidine, L-histidine hydrochloride monohydrate, polysorbate 20, trehalose, and water for injection

Bizengri is manufactured by Partner Therapeutics, Inc., Lexington, MA 02421.