What is remission? Can a chronic lymphocytic leukemia patient achieve remission?

What is remission? Can a CLL patient achieve remission?

So yes, we can achieve remission, and it's important to define what is remission and what is cure. So remission means that for all the tools that we have available, we cannot detect disease. So you don't see any disease on the scans or we don't see any disease in the bloodwork. So remission means the disease is not detectable.

Is it cured?

No, because we don't really expect to cure CLL. We have ways to cure CLL. Patients can go through transplant and potentially cure CLL but it's probably— the treatment is worse than the disease itself. So, achieving remission nowadays is actually relatively common. We have very effective therapies that have demonstrated enormous responses of great responses, really with undetectable disease, even with the most sensitive tests possible. But the expectation is that you're going to achieve that deep remission, but eventually we're going to see disease again. Remission is defined as a normalization of your blood counts and the ability to no longer to detect any of the cancerous lymphocytes in the blood or the bone marrow. Patients can achieve remission. Some of the drugs that we used to use in the past
had somewhat lower rates of remission. Drugs that we use now are able to achieve at least a partial remission in a greater proportion of patients for longer periods of time. Complete remission, on the other hand, which I just defined as total absence of the cells from the bone marrow and blood and normalization of counts, is seen with some classes of drugs, more so than others. But it has been seen that the need to achieve a complete remission with certain classes of drugs is not paramount. These drugs can actually prolong remission in patients, even if they're in partial remission. They will not need alternative therapies for long periods of time. The class of drugs called BTK inhibitors doesn't usually produce deep responses, but it produces long responses, though most responses are partial. On the other hand, drugs are the class of venetoclax, which is another drug class used for treatment of chronic lymphocytic leukemia. You can actually expect MRD negativity and deep responses. Are there different types of remissions? Yes, you do have definitions for complete remission, partial remission and partial remission with lymphocytosis persistant. Those are things that we know in CLL can also be, with certain classes of drugs, prognostic, but not always.

What's the goal of therapy for CLL?

It's the goal of therapy in CLL depends on the type of therapy employed because certain classes of drugs do not produce deep remissions. As we said, BTK inhibitors just prolong remission as possible with even a partial remission state. Whereas with the class of drugs like BCL-2 inhibitors like venetoclax, depth of remission does seem to correlate with duration of remission. Does it matter if I'm in a complete or partial remission? So these are discussions that you have with each patient as to what their goal of therapy is with venetoclax, you have finite duration therapy. You can give therapy for one or two years and stop and then resume when the disease recurs. With the BTK inhibitors, the duration of therapy is still a time of progression, and they do not produce the deep remissions, but both classes of drugs seem to provide a similar benefit in terms of the duration of remission. And you use one and use the other subsequently. In fact, new trials are looking at combining the drugs to give both drugs in a finite period of therapy paradigm.