Pembrolizumab showed clinical benefit in malignant pleural mesothelioma

Share :
Published: 29 Apr 2015
Views: 3457
Rating:
Save
Dr Evan Alley - University of Pennsylvania, Philadelphia, USA

Dr Alley talks to ecancertv at AACR 2015 about the results of a phase I multi-centre trial looking at the use of pembrolizumab in the treatment of a variety of cancers. The drug showed signs of clinical benefit in patients with malignant pleural mesothelioma.

Read the news story for more.

 

 

 

 

 

Presented today, a study today, was the preliminary results, safety and efficacy of a study called KEYNOTE-028. This is a trial using a drug, pembrolizumab, that’s a PD1 antibody.

This was a phase Ib multicentre international study using the drug in twenty different tumour types. Now, what we presented today was the mesothelioma cohort.

The design of the study is patients who have had prior treatment for mesothelioma and had failed that therapy. Patients were all screened, the tumours were screened, for the presence of marker called PDL1, so these were all PDL1 positive mesothelioma.

Patients received treatment with pembrolizumab at a dose of 10mg/kg every two weeks and then were assessed for response after every eight weeks of therapy.

The results that we presented today were the initial safety and preliminary efficacy results.

What we found was that overall the treatment was well tolerated, there were no unexpected toxicities, nothing that was new in any way.

No patients had to discontinue with treatment due to any kind of treatment related adverse events.

Our efficacy data, at least the preliminary data so far, we found we had a total of seven patients who responded to the treatment, that’s a 28% response rate.

But in addition to that we also found twelve patients who had stable disease, the disease didn’t progress during the course of therapy. So overall we have a disease control rate of 76%.

This is important in this patient population, these were all in the second line treatment patients.

Historically there is no proven second line therapy for this disease and chemotherapy has response rates usually 10% or less so we felt these results were encouraging and certainly warrant further investigation of pembrolizumab in mesothelioma.

I think this is a glimpse of the future in this disease.

This is showing that immunotherapy has a role in the treatment of mesothelioma, I believe.

Certainly we need larger studies, this was a small 25 patient, highly selected, enriched patient population.

There is a study just opened that will be looking at in a larger context the treatment for patients with mesothelioma.

It’s, again, pembrolizumab but looking at not only just the PDL1 positive patients but also PDL1 negative patients.

Then beyond that, looking at this drug in combination with other treatments, in combination with chemotherapy, in combination with other immunotherapies, ways to enhance the response.

A 28% response rate is very encouraging but certainly that means that there are a lot of patients who aren’t responding.

If there’s a way that we can try and enhance that response and enhance the duration of response it would be even better.

If you look at mesothelioma it’s really a uniformly fatal disease.

From the time of diagnosis with standard treatment, there’s a standard chemotherapy regimen - a combination of cisplatin and pemetrexed, the overall survival, the median overall survival for this disease, is around 13 months.

So it’s a bad disease and a bad prognosis.

In the second line there really is no therapy so patients who relapse, there’s no proven second line treatment.

So this is why this patient population is particularly at need for treatment.

So we feel that this initial data are encouraging in that regard.