A major medical breakthrough brings new hope to people fighting stomach and esophageal cancers. Jazz Pharmaceuticals announced that the U.S. Food and Drug Administration (FDA) approved a targeted drug called Ziihera® (zanidatamab-hrii).
The approval includes Ziihera® in combination with Tevimbra (tislelizumab-jsgr) and chemotherapy for certain patients with HER2-positive disease, as well as Ziihera® plus chemotherapy for patients whose tumors are strongly HER2-positive.
This approval is for adults with advanced HER2-positive gastroesophageal adenocarcinoma, a type of cancer affecting the stomach and the tube connecting the mouth to the stomach (the esophagus). Ziihera® is approved as a first-line treatment, meaning patients can receive it as part of their initial care plan when combined with standard chemotherapy (with or without an immunotherapy drug like tislelizumab).
This approval represents an important step forward for patients facing HER2-positive gastroesophageal cancer, offering a dual-targeted option right at the start of their treatment journey.
How Does Ziihera® Work?
Ziihera® is a targeted therapy known as a bispecific antibody. Many stomach and esophageal tumors have too much of a specific protein on their surface called HER2, which acts like an accelerator pedal, causing cancer cells to grow and spread quickly.
Unlike older treatments that attach to only one spot on the protein, Ziihera® attaches to two different sites on the HER2 protein at the same time. This double-action approach blocks growth signals more effectively and helps the body's immune system locate and destroy the cancer cells.
What Do the Clinical Trial Results Show?
The FDA based its approval on powerful results from the global HERIZON-GEA-01 clinical trial. Researchers studied how well Ziihera® worked when added to standard chemotherapy:
Tumor Shrinkage: Patients who received Ziihera® alongside chemotherapy saw a significantly higher objective response rate, meaning more patients experienced noticeable tumor shrinkage compared to standard care alone.
Longer Progression-Free Survival: The treatment successfully slowed down the disease, giving patients more time before the cancer advanced. The risk of cancer progression or death was reduced by 35%.
Brain & Bone Coverage: Because advanced gastroesophageal cancers can spread, researchers monitored overall disease control closely, noting durable responses across diverse patient groups.
Common Side Effects to Expect
Like all cancer treatments, Ziihera® can cause side effects. During clinical trials, the most common side effects reported by patients included:
Diarrhea
Allergic or infusion-related reactions (during or shortly after receiving the IV)
Nausea and fatigue
Low potassium levels
Rash
Nerve-related symptoms known as neuropathy
Can lower the heart ejection fraction ( how well it pumps); doctors should check heart function before and during treatment
Your care team will monitor you closely during infusions and can prescribe medications to help manage side effects like nausea or diarrhea.
Finding the Right Care and Next Steps
If you or a loved one has been diagnosed with advanced stomach or esophageal cancer, knowing your tumor's biomarker status is essential.
Ask for Biomarker Testing: Talk to your oncologist to confirm whether your cancer is HER2-positive. Ziihera® is specifically designed for tumors with this genetic feature.
Discuss First-Line Options: Ask your doctor if adding Ziihera® to your initial chemotherapy plan is right for your specific stage of care.
Explore Local Care & Research: Accessing top-tier treatment often involves seeking care at specialized cancer centers near you.
