Introduction to Trastuzumab and HER2-Positive Cancer
Trastuzumab is a targeted cancer therapy classified as a monoclonal antibody [1.5.6]. It is pronounced 'tras-TOO-zoo-mab' [1.2.2]. This medication is specifically designed to treat cancers that have an abundance of a protein called human epidermal growth factor receptor 2, or HER2 [1.2.2]. When a cancer is deemed 'HER2-positive,' it means the cancer cells produce extra amounts of this protein, which promotes their growth and division [1.5.2, 1.5.6]. Trastuzumab works by binding to these HER2 receptors on the cancer cells, which blocks them from receiving growth signals and can help the immune system kill the cancer cells [1.2.5, 1.4.2].
This targeted approach makes trastuzumab a crucial treatment for HER2-positive breast cancer (in early, locally advanced, and metastatic stages) and certain types of HER2-positive stomach (gastric) or gastroesophageal junction cancers [1.5.2, 1.5.6]. Patients must have their cancer cells tested to confirm they are HER2-positive before this treatment is considered [1.2.2]. The drug is typically administered as an intravenous (IV) infusion or an injection under the skin [1.2.7].
The Original Brand Name: Herceptin
The first and most widely recognized brand name for trastuzumab is Herceptin [1.2.5]. Developed by Genentech, Herceptin was approved for medical use in the United States in September 1998 [1.2.7]. For many years, Herceptin was the primary form of trastuzumab available to patients. It revolutionized the treatment of HER2-positive breast cancer, significantly improving patient outcomes [1.4.2]. It can be used alone or in combination with other chemotherapy medications [1.2.7, 1.5.2].
The Rise of Biosimilars
In recent years, the landscape of trastuzumab has expanded with the introduction of biosimilars. A biosimilar is a biological product that is highly similar to an already FDA-approved biologic, known as the 'reference product' [1.7.1]. In this case, Herceptin is the reference product.
It's important to understand that biosimilars are not the same as generic drugs. Generic drugs are exact chemical copies of their brand-name counterparts [1.7.2]. Biologics like trastuzumab, however, are large, complex molecules made from living sources (like animal cells or microorganisms), making them impossible to copy exactly [1.7.2, 1.7.4]. Instead, biosimilars undergo rigorous testing and evaluation by regulatory bodies like the FDA to ensure they have no clinically meaningful differences from the reference product in terms of safety, purity, and potency [1.7.1, 1.7.3]. They are expected to provide the same treatment benefits and have the same potential side effects [1.7.2].
The primary benefit of biosimilars is that they introduce competition and can be more affordable, potentially saving the healthcare system billions of dollars and increasing patient access to critical treatments [1.7.4].
FDA-Approved Trastuzumab Biosimilars
Several biosimilar versions of trastuzumab have been approved by the U.S. Food and Drug Administration (FDA) and are available to patients. These alternatives provide the same therapeutic action as Herceptin. As of recent approvals, the following trastuzumab biosimilars are recognized in the U.S.:
- Ogivri (trastuzumab-dkst) [1.3.4]
- Herzuma (trastuzumab-pkrb) [1.3.4]
- Ontruzant (trastuzumab-dttb) [1.3.4]
- Trazimera (trastuzumab-qyyp) [1.3.4]
- Kanjinti (trastuzumab-anns) [1.3.4]
- Hercessi (trastuzumab-strf) [1.3.4, 1.8.5]
Each of these biosimilars has a unique four-letter suffix attached to the nonproprietary name 'trastuzumab' to distinguish it from the reference product and other biosimilars.
Comparison of Trastuzumab Products
| Product Name | Type | Suffix | First U.S. Approval |
|---|---|---|---|
| Herceptin | Reference Product | N/A | September 1998 [1.2.7] |
| Ogivri | Biosimilar | -dkst | December 2017 [1.8.1, 1.8.5] |
| Herzuma | Biosimilar | -pkrb | December 2018 [1.8.1, 1.8.5] |
| Ontruzant | Biosimilar | -dttb | January 2019 [1.8.1, 1.8.5] |
| Trazimera | Biosimilar | -qyyp | March 2019 [1.8.1, 1.8.5] |
| Kanjinti | Biosimilar | -anns | June 2019 [1.8.1, 1.8.5] |
| Hercessi | Biosimilar | -strf | April 2024 [1.8.2, 1.8.3] |
Potential Side Effects and Management
Like all potent medications, trastuzumab and its biosimilars can cause side effects. It is critical for patients to be monitored closely by their healthcare team. Common side effects include headaches, nausea, diarrhea, and trouble sleeping [1.2.1].
More serious potential side effects involve:
- Heart Problems: Trastuzumab can lead to cardiac issues, including congestive heart failure. Heart function is typically monitored before and during treatment [1.6.6].
- Infusion Reactions: Fever and chills can occur, especially with the first infusion. More severe reactions like shortness of breath or low blood pressure are rare but possible [1.6.6].
- Lung Problems: In some cases, lung toxicity can occur. Any new or worsening cough or shortness of breath should be reported to a doctor immediately [1.6.6].
- Low White Blood Cell Count: This can increase the risk of infection. Patients should watch for signs of infection like fever or chills [1.6.6].
Exposure to trastuzumab during pregnancy can harm an unborn baby, so effective contraception is required during and for seven months after treatment [1.5.2].
Conclusion
In summary, another name for trastuzumab is its original brand name, Herceptin. Additionally, several biosimilar versions, such as Kanjinti, Ogivri, Herzuma, Ontruzant, Trazimera, and Hercessi, are now available [1.2.1, 1.8.5]. These biosimilars have been rigorously tested and approved by the FDA, offering safe, effective, and often more affordable alternatives for treating HER2-positive cancers [1.7.2]. The availability of these different names for the same core medication reflects the evolution of cancer treatment, providing more options for physicians and patients.
Authoritative Link: For more detailed information on trastuzumab and its biosimilars, visit the National Cancer Institute [1.2.5].
