If you are facing a recurrence of classic Hodgkin lymphoma, or you have become resistant to your treatment, there is some good news that may help. The FDA approved Keytruda (pembrolizumab), which is a PD-1 inhibitor, for people who relapse after their first treatment or who don't respond to first-line treatment. Many people with relapsed or treatment-resistant classic Hodgkin lymphoma may have already been taking the drug off-label (that’s when you take a drug for one condition, though it’s FDA approved for a different condition) or through clinical trials.
Read More“The FDA approval is welcome news and will prevent issues with insurance approval for what has already become standard of care in this disease.”
Keytruda Extends Survival
Keytruda earned the FDA nod based on the results of the Phase 3 KEYNOTE-204 trial in which Keytruda reduced the risk of disease progression or death by 35% compared to the drug Adcetris (brentuximab vedotin). Median progression-free survival was 13.2 months on Keytruda versus 8.3 on Adcetris.Easy-to-miss symptoms can lead to late diagnosis in lymphoma, Dr. Elise Chong says.
"The improvement in progression-free survival was in part due to better tolerability for pembrolizumab and a greater likelihood that patients could remain on pembrolizumab for a longer period of time compared to patients receiving brentuximab vedotin," Stephen Ansell, MD, PhD, tells SurvivorNet. Ansell researches immune response in blood cancers at Mayo Clinic in Rochester, MN.
Releasing the Brakes on the Immune System
Keytruda is a checkpoint inhibitor that blocks PD-1. That's a protein on the surface of immune cells that prevents the immune system from attacking healthy cells. PD-1 serves as a checkpoint for other cells in the body. Whenever immune cells with PD-1 on the surface detect other cells with PD-L1 on their surface, the immune cells know to leave those cells alone. Those cells get to pass through the checkpoint. The problem is that some cancer cells have PD-L1 on their surface. That's how they manage to grow and spread in your body without any pushback from the immune system. Essentially, the cancer cells are masquerading as normal cells and tricking your immune system.
Related: 7 Sneaky Symptoms of Hodgkin Lymphoma
Keytruda and other drugs in its class block the PD-1 protein. That way, your immune cells no longer have a checkpoint system that allows cancer cells to move freely about the body. Eliminating this checkpoint causes your immune cells to unleash an all-out attack on the cancer cells.
FDA has already approved Keytruda for use in numerous other cancers, including certain non-small cell lung cancers, melanomas and renal cell carcinomas among multiple others. Classic Hodgkin lymphoma is the latest to join the list of indications.
"Antibodies that block PD-1 signaling, such as pembrolizumab, are now the preferred treatment for relapsed and refractory classical Hodgkin lymphoma," Ansell says.
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