Atezolizumab (Tecentriq) is an immunotherapy drug currently under study in clinical trials to treat mesothelioma. It is already used to treat bladder, breast, and lung cancers.[1] If you are interested in getting involved in a trial with atezolizumab, talk to your specialists to determine if you qualify for clinical trials.
What Is Atezolizumab?
Atezolizumab is the generic name for a drug with the brand name Tecentriq®. It is an immunotherapy drug made by the biotech company Genentech.
What Is Atezolizumab Used to Treat?
Atezolizumab was first approved by the U.S. Food and Drug Administration (FDA) to treat advanced and metastatic urothelial carcinoma, also known as bladder cancer.[2]
The FDA gave accelerated approval of the drug for special cases of bladder cancer. These include patients who cannot be given platinum-based chemotherapy drugs or who were given chemotherapy but experienced progression of the tumors.[2]
The FDA has granted full approval to atezolizumab for patients with non-small cell lung cancer in similar situations.[3] Those who see their disease progress after treatment with platinum chemotherapy drugs can be given atezolizumab. It’s given to patients with this type of lung cancer along with carboplatin, paclitaxel, and another immunotherapy drug, bevacizumab.
More recently, the FDA granted full approval for atezolizumab to be used as first-line treatment in extensive-stage small cell lung cancer and accelerated approval for use in triple-negative breast cancer with the PD-L1 receptor-positive.[4]
Is Atezolizumab Chemo or Immunotherapy?
Atezolizumab is an immunotherapy drug. It is not a type of chemotherapy, although it is often used along with chemotherapy drugs. Atezolizumab immunotherapy works with the body’s immune system to attack and kill cancer cells.
As an immunotherapy drug, atezolizumab immunotherapy works with the body’s immune system to attack and kill cancer cells.
How Atezolizumab Works
Atezolizumab is an antibody that has been designed to target a specific protein on the outside of cancer cells. Immune system cells, known as T-cells, need to recognize the tumor cells and distinguish them from healthy cells.
Normal cells in the body have proteins on their surfaces known as immune checkpoints. When a T-cell binds to one of these, it recognizes it as normal and not a threat.
Cancer cells have evolved to trick the immune system into thinking they are normal healthy cells. They express checkpoint proteins that signal to the immune cells the same way healthy cells do.
Different types of tumors and individuals with cancer have cancer cells that may express different types of these checkpoint proteins.
Atezolizumab inhibits the interaction between immune T-cells and a specific checkpoint protein on cancer cells known as PD-L1. It works by binding to PD-L1 and preventing T-cells from binding there. In this way, the drug unmasks the cancer cells, and the immune system can recognize they are unhealthy and should be targeted for destruction.[5]
Atezolizumab is specific to tumors whose cells express PD-L1. Some types of cancers express more of this protein than others, like bladder cancer.
Still, there are also individual differences, so one person may have cancer with more PD-L1 and may benefit from this treatment more than another. Some cancers have been shown to respond to this treatment even though they may not express any PD-L1.
Can Mesothelioma Be Treated with Immunotherapy Like Atezolizumab?
Potentially, any type of cancer can be treated with immunotherapy. There are many promising new immunotherapy treatments for mesothelioma, including atezolizumab.
Immunotherapy effectiveness often varies by individual. Some mesothelioma patients might get major benefits from atezolizumab while others do not.
Atezolizumab/Bevacizumab Mesothelioma Clinical Trial
The success rate of atezolizumab for mesothelioma treatment has been limited when used alone. A clinical trial that is active but not recruiting combined atezolizumab with bevacizumab hoping for better results.
Bevacizumab is an antiangiogenic drug, meaning it stops the growth of blood vessels that support tumors.
The trial includes patients with peritoneal mesothelioma. At the one-year mark, researchers recorded overall survival at 85% and progression-free survival at 61%. This is a significant improvement from standard therapy.[6]
Atezolizumab Clinical Trials Recruiting Mesothelioma Patients
Mesothelioma tumors often overexpress PD-L1, making it a good candidate for trials using atezolizumab. These are some current clinical trials involving atezolizumab, some of which are recruiting patients with mesothelioma, mostly outside of the U.S.:
- Integration of the PD-L1 Inhibitor Atezolizumab and WT1/DC Vaccination Into Platinum/Pemetrexed-based First-line Treatment for Epithelioid Malignant Pleural Mesothelioma (Immuno-MESODEC). The purpose of this study is to determine the safety of platinum and pemetrexed chemotherapy with atezolizumab and a vaccine and to see if it induces an immune response in patients.[7]
- Chemotherapy With or Without Immunotherapy for Peritoneal Mesothelioma. This study is a rare opportunity for peritoneal mesothelioma patients to benefit from a new treatment. Participants receive either standard treatment (surgery plus HIPEC) or standard treatment with atezolizumab. Study locations include Arizona, Illinois, Kentucky, Massachusetts, Minnesota, North Dakota, Ohio, Oklahoma, Pennsylvania, and South Dakota.[8]
- Mesothelioma Stratified Therapy (MiST): A Multi-drug Phase II Trial in Malignant Mesothelioma (MiST). This study, ongoing in the UK, is using atezolizumab and other drugs to develop more personalized treatments for mesothelioma patients with recurrences.[9]
- Immunological Variables Associated to ICI Toxicity in Cancer Patients. This study is ongoing in Belgium and is recruiting a range of patients with solid tumors, including mesothelioma. The purpose of the study is to determine adverse events in patients receiving immunotherapies like atezolizumab.[10]
While many of these studies are out of reach for American mesothelioma patients, they should provide useful results that help patients everywhere.
Potential Side Effects
Immunotherapy drugs typically cause milder and fewer side effects than chemotherapy because they are more targeted, but they can still have undesirable consequences.
The most common side effects and adverse events of atezolizumab include:[2]
- Fatigue
- Constipation
- Nausea
- Loss of appetite
- Diarrhea
- Fever
- Urinary tract infections
- Cough
- Difficulty breathing
Contact your doctor immediately if you have an unusual cough or diarrhea, as these side effects can quickly become dangerous.
Atezolizumab is not yet approved for treatment in patients with mesothelioma, but it is accessible through clinical trials. Researchers are hoping that it can help shrink tumors or slow the growth of cancer in mesothelioma. Results are not yet available, and trials are ongoing. To find out if you qualify for a clinical trial, talk to your medical team.
