Clinical trial doctor

We often discuss the results of clinical trials so let’s discuss clinical trials in more depth: who participates, what’s being tested, how clinical trials change treatment of future mesothelioma patients.

Clinical trials often form the foundation for treatments given to most cancer patients. Physicians design some clinical trials to identify a disease mechanism. Other clinical trials test whether treatment A is better than treatment B: a clinical trial compares their efficacy--how well the tumor is killed, how long before a tumor begins growing again, the patient’s length of survival or preferably total cure-- and the side effect profile--how well patients feel during therapy, any serious complications. Some clinical trials check the safety of a new drug and determine the appropriate dosage for treating humans.

Participants in clinical trials help future mesothelioma patients. In some but not all cases, participants may benefit from participating in a clinical trial if the treatment they receive works better in them than the standard care. It’s important to discuss potential participation in any clinical trial with your family and your doctor.

Many clinical trials are testing new therapies or new combinations of therapies for mesothelioma. Here are three clinical trials that are recruiting patients.

Placebo Controlled Study of VS-6063 in Subjects With Malignant Pleural Mesothelioma

Briefly, VS-6063 blocks one of the major signaling proteins, focal adhesion kinase or FAK, in cancer stem cells. Although cancer stem cells make up a minor portion of the tumor mass (about 4%), cancer stem cells have the ability to renew and produce more cancer stem cells and cancer cells. If all cancer stem cells die, then the tumor will eventually die.

This phase II study compares the ability of VS-6063 versus a placebo to eventually kill mesothelioma. Clinicians will report overall survival, the duration of response to tumor, and the quality of life. The clinical trial is scheduled to continue recruiting mesothelioma patients through July 2016.

Pemetrexed Disodium and Cisplatin With or Without Cediranib Maleate in Treating Patients With Malignant Pleural Mesothelioma

Many mesothelioma patients are treated with the chemotherapeutic agents, pemetrexed disodium and cisplatin. This phase I/II clinical trial adds a third drug, Cediranib, to the regimen. This clinical trial is determining the side effect profile of cediranib and its best dose in humans.

Evidence in animals and human cells suggest that cediranib blocks the tumor’s signals to the cells lining arteries and veins and the making of more blood vessels. Since tumor cells need more blood vessels for the tumor nodules to grow (a process called angiogenesis), cediranib may hinder tumor growth by blocking growth of its blood supply. Cediranib actually blocks the signaling of the vascular endothelial growth factor (VEGF) receptors to tell the cells lining the blood vessels to grow more blood vessels.

Cediranib has been tested in patients with alveolar soft part sarcomas and ovarian cancer so the side effect profile in humans is becoming evident.1 Although grade 3 toxicity was experienced in 50% of patients, Dr. Raja stated that “the addition of cediranib to platinum-based chemotherapy is sufficiently well tolerated …to progress to stage II [phase II trial].”1

Intrapleural Administration of HSV1716 to Treat Patients With Malignant Pleural Mesothelioma

HSV1716 is a crippled virus that replicates in tumor cells but not normal cells. It belongs to the class of biologics called oncolytic viruses: viruses that kill cancer cells, acting like pac-man. This phase I/II clinical study involves HSV-1716 administration into the chest cavity of mesothelioma patients who are not eligible for tumor removal or reduction by surgery. Clinicians seek to evaluate the safety profile and appropriate dosage of HSV1716 in mesothelioma patients.

A trial of 12 patients with glioblastoma observed a very low side effect profile and 3 patients had longer than expected survival.2 Dr. Harrow concluded that “the survival and imaging data, in addition to the lack of toxicity, gives us confidence to proceed to a clinical trial to demonstrate efficacy of HSV1716 in glioma patients.”

Choosing to Participate in a Clinical Trial

There are multiple clinical trials that are currently recruiting new patients with mesothelioma.

Joining a clinical trial is a personal decision. The potential participant should also discuss the possibility of joining a clinical trial with their physician and family. Some questions to ask are:

  • What are the potential benefits to the mesothelioma community and to me particularly?
  • What are the potential risks to me? Do I have any diseases that are in common with the known side effects of the agent in the clinical trial? If so, could it aggravate it?
  • Would you as the physician, recommend this to your loved one? Why?

Several cancer centers have more than one clinical trial that is recruiting patients.