Researchers are looking at a new treatment for mesothelioma. It is a multimodal treatment (multiple treatments combined) consisting of the immunotherapy drug Keytruda and a new drug called OT-101. OT-101 is an antisense drug, which is a drug that blocks molecules that make certain proteins. The drug is also effective at treating COVID-19. It blocks a cellular pathway that both mesothelioma and COVID-19 use. Researchers are hoping that mesothelioma patients will benefit from a combination of OT-101 and Keytruda.
The drug manufacturer, Oncotelic Therapeutics, Inc. is making the drug for multiple types of cancer and viruses. It blocks the transforming growth factor beta two (TFG-β2) protein. This protein is targeted because it can help cancers and viruses evade the immune system. The company has found that OT-101 is effective based on information gathered from early trials. The trials involved patients with solid tumors and COVID-19 separately. One hard to treat cancer that was tested was Glioblastoma. Around one quarter of the patients treated in the trial had some type of response (tumors shrank or disappeared). Nine percent of patients did not have cancer growth or progression for a minimum of six months. Around 33 percent of the patients had a median survival of 3.5 years, which is better than the typical half year chemotherapy patients normally experience.
There were also promising results for COVID-19. All patients in the study received the standard treatment with either a placebo or OT-101. The OT-101 groups had a 75 percent lower mortality rate compared to placebo patients. This could mean that OT-101 might possibly be useful for other respiratory illnesses like the flu.
COVID-19 and mesothelioma can be treated with the same medication because they exploit similar pathways. The medication blocks the TGF-β2 protein that is involved in both illnesses. Cancer cells and the virus that causes COVID-19 use this protein to avoid the immune system. When the protein is blocked, the immune system is able to see and target the virus and cancer cells. OT-101 can even be combined with other immunotherapy drugs to make them work more effectively.
The results are promising when OT-101 treats solid tumors. A new trial will soon be announced that will help determine if the drug is effective on mesothelioma. The other part of the study, Keytruda, has already been tested for mesothelioma. When used by itself, Keytruda was not found to be any more effective than regular chemotherapy, but it has been effective alongside CAR T-cell therapy. When patients were treated with the combination of the two, survival in patients was extended by around one year.
Doctors are hopeful that OT-101 and Keytruda will be effective for mesothelioma, but it is too soon to know for sure if this will be the case. The study proposal was submitted at the end of 2021 and there is still no update on its approval status. Clinical trials like the one for OT-101 improve lives. If you think you could be eligible for a clinical trial, look at our clinical trials page to find recent trials for mesothelioma.