Typically, the first line of treatment for ovarian cancer is chemotherapy. However, researchers and doctors such as Oliver Dorigo are investigating alternatives for initial treatment for ovarian cancer, as well as alternative options for maintenance therapy.
One of the drugs that they are working with is called atezolizumab, which is the molecular name for the drug Tecentriq.READ MORE
Checkpoint inhibitors help enhance the immune system’s ability to fight cancer.
“Those immune checkpoint inhibitors have made a huge difference for patients,” says Dorigo. Many tumors have been responsive to immune checkpoint inhibitors—including melanoma tumors and lung cancer tumors among many other types, according to Dorigo.
Now, clinical trials are being conducted to evaluate how ovarian cancer tumors will respond to checkpoint inhibitors.
Clinical trials for ovarian cancer are testing to see if atezolizumab can be helpful in ovarian cancer treatment as a part of initial treatment for patients. Researchers are looking to see about the efficacy of atezolizumab in the first line of treatment.
“We are adding atezolizumab in a clinical trial,” says Dorigo.
Atezolizumab is a monoclonal antibody, which is a newer type of targeted cancer therapy.
Chemocare.com explains how the drug works to fight cancer:
“The immune system utilizes activators/stimulators (accelerators) and checkpoints (breaks) to maintain the balance. One of those checkpoints is the interaction between two proteins, called PD-L1 and PD-1, that can cause suppression of the immune system and thus diminished attack against cancer cells. Both cancer cells and immune system cells can may over-express on their surface PD-L1, and this can reduce the attack of the immune system against cancer cells. Atezolizumab is a monoclonal antibody that attaches to PD-L1 and “blocks” its checkpoint function, thus ‘unleashing’ the brake on the immune system, to attack cancer cells.”
Atezolizumab, is administered to the patient intravenously, says chemocare.com. For the first infusion, the drug will be given to the patient for 60 minutes and then for the treatments thereafter, in 30 minute increments. The treatment cycle for atezolizumab is 21 days, or three weeks. The most common side effect of atezolizumab is fatigue.
In this trial atezolizumab will be added to a chemotherapy regimen and combined with the already FDA-approved immunotherapy drug, Avastin, to see if it helps to treat patients with ovarian cancer.
Clinical trials are also being done with atezolizumab for maintenance therapy. Maintenance therapy is given to help treat cancer patients after initial treatment, or first line treatment, to halt any cancer growth.
The ultimate goal, using immunotherapy, and any other treatment, should be to stop cancer from coming back entirely, according to Dorigo.
“And this is where we are going to make a meaningful impact on overall survival,” says Dorigo.
“I think that drugs like atezolizumab have the potential to generate what we call memory immune responses. There are a variety of cells in the immune system that are very capable of remembering what the cancer looks like. And as time goes by, the key is controlling any cancer cell that might regrow.”
If the immune system can remember what the cancer looks like, it can help stop a relapse from occurring.
Dorigo says that while the data might take a long time to collect, these are promising, exciting new strategies that take advantage of new drugs that have been developed, including, he says, in the space of immunotherapy.