There are just a handful of chemotherapy agents approved by the U.S. Food and Drug Administration (FDA) for the treatment of mesothelioma. Right now the FDA-approved chemotherapy drugs for mesothelioma are cisplatin, carboplatin, gemcitabine and pemetrexed.
But there eventually might be one more to add to that list, thanks to new research making the case for the drug trabectedin.
Trabectedin is already approved by the FDA for treatment of liposarcoma and leiomyosarcoma. These are soft-tissue sarcomas. Patients who have those cancers get trabectedin if surgery isn’t possible and tumors have spread, despite being treated earlier with a chemo agent from the anthracycline family of drugs.
Trabectedin is already being used for mesothelioma in the U.S. But it’s only offered as an off-label treatment. Doctors are usually hesitant to prescribe anything that isn’t FDA approved.
So obtaining FDA approval for trabectedin as a mesothelioma chemotherapy agent would likely encourage its wider use.
Mesothelioma Interferes with Apoptosis
Each of those four FDA-approved mesothelioma chemotherapy drugs are effective. But they can only do so much.
As a result, mesothelioma doctors are always hoping for additional chemotherapy options. That’s why the research in support of trabectedin is welcomed.
The new research comes from scientists in Austria. They are based at the Medical University of Vienna’s Comprehensive Cancer Center and at Vienna General Hospital.
Their findings were published in the journal Molecular Cancer Therapeutics. This is a publication produced by the American Association for Cancer Research.
The purpose of the study was actually to see how well trabectedin works when paired with other agents. The other agents used were cisplatin, obatoclax and venetoclax.
The researchers found that putting trabectedin together with cisplatin worked remarkably well. Obatoclax and venetoclax also worked well, because they inhibit the protein bcl-2.
Bcl-2 is a protein that plays an important role in regulating apoptosis. Apoptosis is a term for the natural process by which damaged or diseased cells kill themselves to save neighboring healthy cells.
Mesothelioma causes bcl-2 to go haywire. This stops apoptosis from happening. Mesothelioma cells that should be killing themselves just keep on going and growing.
The researchers found that trabectedin helps obatoclax and venetoclax do a better job of getting bcl-2 back under control so that apoptosis can occur.
“When trabectedin is combined with these bcl-2 inhibitors, there is a significant improvement in destruction of malignant pleural mesothelioma cells,” said the researchers.
Trabectedin Tested on Mesothelioma Cells
The researchers made their observations using trabectedin applied to mesothelioma cells in a lab dish and then to mesothelioma cells growing inside lab mice.
They also put their findings to a test with a clinical trial conducted in Italy. The results of that study helped convince the researchers that trabectedin has a lot of potential as a mesothelioma treatment option.
Something interesting about trabectedin is that its active ingredient is based on a protein from an underwater creature called the sea squirt.
So don’t be surprised if you take trabectedin and then feel a little seasick afterward, because a common side effect of trabectedin is nausea.
That’s actually pretty mild as trabectedin side effects go. The FDA warns that trabectedin’s serious side effects may include blood infections and liver damage.
Still, the benefits of trabectedin as an FDA-approved mesothelioma chemotherapy treatment are likely to outweigh the risks. Stay tuned to see whether trabectedin goes on to become a chemo mainstay like cisplatin, carboplatin, gemcitabine and pemetrexed.