Dr. Matthew Davids reviews current chronic lymphocytic leukemia (CLL) treatment approaches and discusses the role of watch and wait.
Dr. Matthew Davids is the Associate Director of the CLL Center at Dana-Farber Cancer Institute. More about this expert.
Dr. Matthew Davids: So, we’re very fortunate in CLL that we have a number of very effective treatment options. But I would like to start by highlighting the fact that, for the majority of CLL patients when they’re first diagnosed, a watch and wait or observation strategy is generally preferred.
And this goes back to many years of research showing that there’s no survival advantage to starting early with chemotherapy-based approaches.
And we have some recent data with the newer drugs that, even with these better agents in terms of the tolerability, that early intervention strategies still probably don’t make a difference for our patients and are associated still with side effects and risks. So, the first important thing is to understand that it’s okay to be observed and go on to this watch and wait strategy, and that many patients can stay on this type of approach for many years.
However, once treatment is indicated, we do have a number of therapy options for CLL patients. And these go back to chemotherapy-based approaches, which have been around for quite a while now and now include some newer drugs that we call novel agents that are really transforming how we manage the disease. So, for younger, fitter patients, we can still think about chemoimmunotherapy, and in particular a regimen called FCR, which includes two chemotherapy drugs, fludarabine and cyclophosphamide, and a third drug which is an antibody called rituximab.
And this combination works very well, in particular for patients who are very fit and can tolerate it and remains a viable option. An advantage of this approach is that it’s time limited. It’s a six-month course. But there are some significant side effects from chemotherapy and some longer-term risks. And so, it’s something that we think carefully about before we recommend.
We really think about the novel agents now as being a good option for most of our patients with CLL. And these novel agents are typically pills that, in general, tend to be well tolerated, although each one has its unique risks and potential side effects. We’ve been using the drug ibrutinib now for a few years for the initial treatment of CLL. And this drug targets one of the pathways in the CLL that the cell relies on for its survival. And it’s a drug that patients take once per day. And once they start on it, they usually continue on it for a long period of time. We’ve had patients on this drug up to seven or eight years now who continue to do well.
Ibrutinib doesn’t tend to completely eradicate the CLL. But it often gets patients into very good remissions. And if they tolerate the drug well, then they can stay on it long term and control the disease. But typically, the drug is given as a continuous therapy. So, we don’t have as much experience with stopping it at this point. And so, that’s typically how we recommend giving it, is as a continuous drug.
Now, another new option for the initial therapy of CLL patients is called venetoclax, which is another pill that we have had a lot of experience with over the last few years in clinical trials. It was approved for patients who had previously had treatment for CLL for the last three years or so. And then just recently, the FDA gave approval to venetoclax as a first therapy for CLL patients. And we typically give this in combination with a different antibody drug called obinutuzumab, which is given intravenously.
So, this regimen, which we call venetoclax plus obinutuzumab, is typically given for a six-month combination course, followed by about six additional months of venetoclax pills. And then patients stop therapy at that point.
So, one of the advantages of this approach is that, like the chemotherapy, it’s a time-limited approach for one year. And we can often see very deep remissions that allow patients to remain off therapy for a period of time afterwards.
One of the issues so far is just that we don’t have as long-term follow up as we do with ibrutinib. So, we don’t know what’s gonna happen to these patients seven or eight years after they’ve started venetoclax plus obinutuzumab. We certainly hope that this one year of therapy provides a durable response for patients, and it certainly looks promising in that regard so far. But we currently have more long-term experience with ibrutinib as an initial treatment.
So, these are kind of the main options that we think about for patients who need their first therapy for CLL. We always think about observation first. But when patients do need treatment, we move toward either a chemoimmunotherapy-based approach with a regimen like FCR, or ibrutinib, or venetoclax plus obinutuzumab. And so, it’s great to have all these very valuable and effective options for our patients.