01. Cancer Vaccine Overview
What Are Cancer Vaccines?
Cancer vaccines are treatments that help empower the immune system against cancer. They are a form of immunotherapy. In recent years, other immunotherapies have become more common for mesothelioma patients. Researchers are now looking into the potential of using cancer vaccines to help treat mesothelioma.
The U.S. Food and Drug Administration (FDA) has approved vaccines to treat some cancers. For example, FDA-approved vaccines may be used to treat bladder cancer and prostate cancer.
Clinical trials are also looking into using vaccines to treat other forms of cancer. Researchers have begun looking into the possibility of treating mesothelioma with a vaccine.
Small studies have achieved positive results among patients with malignant pleural mesothelioma. These studies provide encouragement for continuing research. At least one clinical study is ongoing.
Types of Cancer Vaccines
Several types of cancer treatment vaccines are available. Each type works in a different way to achieve an immune response. Types of vaccines generally used to treat different cancers include:
- Bacteria-based vaccines: Vaccines may use bacteria for different purposes. Some bacteria can be modified to teach the immune system to attack cancer cells. Other bacteria have the ability to directly target cancer cells when injected.
- Cell-based vaccines: These vaccines use certain types of cells to stimulate an immune response. For example, some vaccines use immune cells called dendritic cells. These cells are given pieces of a tumor to teach them to recognize and attack tumor cells. Many cell-based vaccines must be custom-made from a patient’s own cells.
- DNA- and RNA-based vaccines: DNA and RNA vaccines enlist healthy cells to manufacture the proteins that vaccinate a person. The DNA or RNA teaches healthy cells to make a protein that is in cancer cells. Another part of the vaccine teaches the immune system to recognize this protein as a target for attack.
- Protein-based vaccines: These vaccines use specific proteins that cancer cells make a lot of (called “antigens”), mixed with an irritant to stimulate an immune response. They teach the immune system to recognize and attack tumor antigens and the cells that make them.
- Virus-based vaccines: Vaccines may use viruses to help treat cancer. For example, some vaccines may use modified viruses called oncolytic viruses. These infect and potentially kill tumor cells. The viruses generally only multiply in tumor cells. So they don’t pose a serious threat to healthy cells.
Researchers are testing different types of cancer vaccines on mesothelioma. The goal of this experimental research is to find a vaccine that encourages the immune system to find and attack mesothelioma cancer cells.
02. Mesothelioma Cancer Vaccines
Cancer Vaccines and Mesothelioma
Vaccines for mesothelioma and lung cancer are areas of interest for researchers. Some mesothelioma vaccine clinical trials have already published promising results. But the full benefits of vaccines are unknown because research is still in its early stages. Other studies are currently underway.
In general, researchers are looking for ways to use vaccines to help treat mesothelioma, not prevent it. Cancer prevention vaccines help protect the body against cancer-causing viruses. The only known cause of mesothelioma is asbestos exposure. Therefore, a vaccine for asbestos is unlikely because asbestos is a mineral, not a virus. However, research into general tumor progression may find a way to help prevent mesothelioma growth.
Vaccines for treating mesothelioma are still experimental. Eligibility for a vaccine will depend on the clinical trial. Patients interested in joining a trial can talk to their mesothelioma doctors. A doctor at a qualified cancer center can explain eligibility for specific clinical trials. They can also explain potential vaccine treatment side effects.
Galinpepimut-S (GPS) Vaccine Clinical Trials
At least two studies have looked at galinpepimut-S (GPS) as a potential mesothelioma vaccine. GPS is a protein-based vaccine that targets antigens produced by tumor cells. Both studies were small but had promising results.
Both studies used GPS as a second line of treatment after other cancer therapies.
In a 2017 study, pleural mesothelioma patients received GPS after surgery. They received six injections spaced two weeks apart. The study reported the following median survival results in the pleural mesothelioma patients:
- Patients who received GPS: 23 months
- Patients who did not receive GPS: 18 months
The study also reported only mild side effects, like injection site reactions and fatigue.
A 2022 study also treated pleural mesothelioma patients with GPS. Patients had already undergone standard chemotherapy with Alimta® (pemetrexed). They were then given GPS and Opdivo® (nivolumab), an immunotherapy drug. The study reported the following results for patients treated with GPS and Opdivo:
- Median survival: 11 months
- Time until disease progression: 3 months
Treatment in this study increased survival almost 35% compared to other forms of second-line treatment.
HSV-1716 Vaccine Clinical Trial
In one small study, researchers used a virus-based vaccine to treat pleural mesothelioma patients. The vaccine consisted of an oncolytic virus derived from the herpes virus. Oncolytic viruses have the benefit of being able to infect and kill cancer cells while being unable to survive in healthy cells.
The 13 patients in the study all had inoperable pleural mesothelioma. Some had received prior chemotherapy treatment. The patients received several doses of the vaccine, called HSV-1716.
The study produced several encouraging results. After treatment, six patients showed no observable signs of tumor progression. The treatment was also well tolerated.
The study notes that these results encourage future research. With additional research, HSV-1716 may become a treatment option for people with inoperable pleural mesothelioma.
Other Clinical Trials for Mesothelioma Cancer Vaccines
Some clinical trials are currently investigating vaccine treatments for mesothelioma, including:
- Poly-ICLC Vaccine Trial: The Poly-ICLC clinical trial is ongoing. Poly-ICLC is an RNA-based vaccine. The study will test the safety and potential efficacy of the vaccine for treatment before surgery.
- UV1 Vaccine Trial: This clinical trial is ongoing. UV1 is a protein-based vaccine. To enroll in this trial, patients must have already received chemotherapy treatment. Study participants will receive Opdivo and Yervoy® (ipilimumab) plus the UV1 vaccine. Opdivo and Yervoy are both types of immunotherapy drugs called immune checkpoint inhibitors.
Resources for Mesothelioma Patients
03. Mesothelioma Survival
How Vaccines Impact Mesothelioma Patients
Vaccines may be able to help improve mesothelioma prognosis. They are a form of immunotherapy. Researchers are interested in several types of immunotherapy for mesothelioma. They have already seen success with therapies like immune checkpoint inhibitors. Vaccines may provide another way to use this innovative form of treatment to improve mesothelioma life expectancy.
Different vaccine treatments have different goals and researchers will measure their results accordingly. This is because vaccines have the potential to provide different types of benefits to cancer patients. Studies may examine survival, time before disease progression or other potential vaccine benefits.
For example, the GPS plus Opdivo study reported on disease progression and median survival. Patients treated with the GPS vaccine went three months without any evidence their mesothelioma had progressed. This may mean these patients experienced a better quality of life during these months.
Researchers are suggesting further mesothelioma vaccine research based on their early results. This may mean larger studies could lead to positive outcomes for mesothelioma patients. Future research could help establish benefits of mesothelioma cancer vaccines.
