Researchers at Barts Cancer Institute (BCI) say a new drug known as ADI-PEG20 “starves” mesothelioma cells, resulting in cell death, while leaving the body’s healthy cells alone. ADI-PEG20 is “particularly promising,” said the team, “because a key issue with chemotherapeutic drugs is their tendency to be quite toxic, due to the fact they affect healthy cells as well as tumor cells. The new drug used in this trial only affects the tumor cells and seems to lack serious side effects.”
In an early trial that included 68 participants, researchers discovered that ADI-PEG20 “deprives tumors of their external source of arginine in the blood (from digested food) by breaking it down.” The tumor cells “then die because they don't have this essential building block to make proteins needed for survival.” This deprivation “changes the way the tumor cells make and distribute their DNA building blocks, and because some chemotherapy drugs target DNA construction, a combination of ADI-PEG20 with chemotherapy could show an even better effect than arginine deprivation alone.”
The results showed that treatment with the arginine-lowering drug significantly slowed down disease progression in 44 patients receiving the drug and best supportive care, nearly doubling the progression-free survival, compared with the 24 patients receiving best supportive care alone. “This the first time a targeted drug treatment has been designed for this type of cancer with a positive effect in a randomized study of patients with mesothelioma,” said the team.
A number of clinical trials for ADI-PEG20 on treating pleural mesothelioma are underway, with possible regulatory approval for one of the indications coming in 2018. One current trial—TRAP (Tumors Requiring Arginine to Assess ADI-PEG20 with Pemetrexed and Platinum)—revealed “unprecedented responses” from a small group of patients with cancers no longer responding to current treatments. The results showed a “100% disease control rate, including a 78% partial response rate, or tumors actually shrinking.” The TRAP Trial includes patients who have diagnoses of aggressive mesothelioma including the sarcomatoid type, which until now, has been untreatable.
Larger Phase II and III trials (to include 150 to 300 or more participants) are currently recruiting in the US, UK, Australia, South Africa, Taiwan, and a number of European countries.
If you have been diagnosed with mesothelioma, talk to your doctor about participating in a clinical trial for potentially life-saving drugs such as ADI-PEG20. Drugs such as these could be effective at treating your specific type of mesothelioma.
Sources
Leech, Zoe. "Encouraging Results for a New Mesothelioma Chemotherapy." Barts Cancer Institute. Barts Cancer Institute (BCI), 27 Apr. 2017. Web. 23 Oct. 2017.
