ASH 2014

Pembrolizumab may bring hope for patients with Hodgkin lymphoma

Dr Craig Moskowitz - Memorial Sloan Kettering Cancer Center, New York, USA

These were patients who you pretty well hit them with everything, including brentuximab, and what did you do with them with this pembrolizumab?

These patients had failed… almost all the patients had failed stem cell transplant and they all failed brentuximab vedotin so they were then enrolled on this phase Ib study where they received pembrolizumab in standard fashion, dosing that is being done in solid tumours. The patients were treated for twelve weeks and then they had repeat imaging. Those who had evidence of tumour shrinkage or lack of disease progression could continue. The bottom line is that almost three-quarters of the patients are still on treatment. The follow-up is still short but we’ve seen a number of complete responses, partial responses and stable disease. What to do in the long term with these patients is unclear to me, with this drug as well as with the competitors’ in patients who are in remission. Whether or not to continue this treatment or to take the patients off the treatment then offer them a transplant.

Now it seems that you’ve taken the brakes off the immune system. Is there evidence that it has actually worked then, this approach?

The response rate is extremely high in Hodgkin lymphoma.

What are your conclusions for doctors then? What are the clinical implications that might come out of this?

These drugs are on a fast track for approval. Will doctors in the community actually be using this or will this be used at major centres? It’s unclear to me. Because patients who have heavily pre-treated Hodgkin lymphoma tend to seek out more expertise but in the beginning when the drugs are approved they’ll be approved for patients where brentuximab vedotin failed and they’ll be given for a finite period of time and then decisions will be made on how to treat the patients further. It’s a treatment strategy in evolution.

Now it’s a phase I study, Ib, 29 patients, what is the basis on which you discuss this as being excellent activity because it was basically for safety, wasn’t it?

Yes, but almost all the patients responded to the treatment and there is a registration trial which will be initiated probably by April by Merck, which is the manufacturer of pembrolizumab, which will be a fairly broad study in Hodgkin lymphoma for accelerated approval.

So what should doctors be taking home, briefly, from this?

As of now this particular drug has unheard of response rates in patients who are heavily pre-treated. And in patients who have failed brentuximab vedotin there is no treatment, the patients are destined to be not with us. So now we have hope for patients who are seeking it.

Could it be applied earlier in different stages of the disease?

It may very well be but we’re a little bit away from that for now.