Cancer research is typically slow, and new treatments are rare. In fact, the United States Food and Drug Administration (FDA) has approved only two new mesothelioma treatments in the past two decades. Nonetheless, researchers continue to look for new treatments, and their work continues to offer new hope.
As we saw in a previous blog, only a small fraction of all research leads to clinical trials. That makes it all the more meaningful when a treatment heads into trials and then advances to the next stage. This is the case for the promising new CAR-T treatment that has recently started into Phase 2 trials.
What does it mean when a treatment enters Phase 2 trials?
As the FDA notes, most new treatments, drugs and medical devices must pass through four phases of clinical trials before they become available to the public. These often follow months or years of theoretical research and tests with animals. The first phases start with small numbers of volunteers. Later phases involve more volunteers. The FDA also identifies separate goals for each phase:
- Phase 1: Researchers work with a small group of volunteers, typically fewer than 100. The main focus is to measure the safety of the treatment, determine safe dosages and identify side effects.
- Phase 2: Researchers work with up to several hundred volunteers. This phase aims to measure the effectiveness of the treatment and continue to track its safety.
- Phase 3: The final stage before the FDA might grant approval. Researchers work with large groups of volunteers to compare the treatment to the treatments already in use. Researchers continue to track side effects and safety information.
- Phase 1V: After the FDA grants approval for public use, researchers continue to track data on the treatment’s risks, benefits and best uses.
While clinical trials for new treatments, such as CAR-T may differ from those for new drugs, the FDA notes that Phase 2 drug trials typically run from several months to two years. That means if all goes well in the Phase 2 trials, more mesothelioma victims might be able to participate in Phase 3 trials within a year or two. They should also have a better understanding of the treatment’s effectiveness and possible side effects.
There’s more to learn, but Phase 1 results were encouraging
Given that only 18 volunteers participated in the Phase 1 CAR-T trials, it may be too early to get excited, but the early results were promising. As reported by Healio, the one-year survival rate for the trial participants was 83%. The median survival rate was 23.9 months. Those numbers compare favorably to the general one-year survival rate of 73% and median survival rate of 18 months.
Importantly, the volunteers suffered no serious side effects. Moderate side effects included:
- Trouble swallowing
- Blood clotting
These side effects were largely blood-related, and this owes to the fact the treatment manipulates patients’ white blood cells. In the CAR-T treatment, physicians remove some of the patients’ T cells. They then program these cells in the lab to attack the patients’ cancer cells. Finally, the physicians delivered the modified T cells straight to the diseased tissue.
Who can participate in clinical trials?
Clinical trials require volunteers willing to participate. Researchers typically screen potential volunteers, and your screening would likely involve a review of your health history, plus things like a physical examination and blood test.
Because clinical trials take months or years to complete, there are often multiple clinical trials running at the same time. You can talk with your doctor about the trials that are looking for volunteers and to determine if one might be right for you.