Mets Day 1019: Georgetown's clinical trial

Today I met with Dr. Nancy A. Dawson at Georgetown University Hospital to discuss the MPDL3280a trial. She explained that the only trial that she had open was the Phase III trial that compared patients who received the anti-PD-L1 drug to patients receiving a taxene-based chemotherapy. The Phase II trial that had everyone getting the anti-PD-L1 drug had been fully subscribed last Fall, and was closed to all patients who had previously received chemotherapy (the so-called "cohort 2" of the trial). The reason why that Phase II trial showed on clinicaltrials.gov that it was still recruiting was that it still had openings in cohort 1, which was limited to patients who had metastatic bladder cancer and who never had received chemotherapy. She added that she was not aware of any currently open clinical trials that ensured that all patients would receive the MPDL3280a drug.

Dr. Dawson also spent some time dialing back my expectations for the MPDL3280a drug. While she acknowledged that the preliminary results that were reported at the 2014 ASCO meeting showing a 50% response rate were very promising, she said that those data did not match her own personal experience, or the experiences of other doctors that she had spoken with who were helping run the Phase II trial. She said that she had enrolled 13 patients in the Phase II trial, and of those 13, one had a complete response, and two had a partial response. The tumors of the other 10 patients continued to grow non-stop. She said that other doctors had also told her that they were seeing a 20% response rate. Based upon that, she said that she would not be surprised if the Phase III trial showed that the response rate for MPDL3280a was about the same as for the taxene-based chemo.

We also discussed how the randomization would work if I was to enroll in the Phase III trial. She said that, as soon as she certified that I met the criteria, Hoffman-La Roche would enter my information, would conduct the computer-based randomization, and we'd be told of the results. She encouraged me to be ready to go through with the trial regardless of the results -- she did not want me (or other patients) to shop for clinical trials, dropping out if I don't get into the arm that I wanted. I understand that from the viewpoint of the objective of the clinical trial, but from my own selfish point of view, I'd rather get the anti-PL-L1 drug than the taxene.

Dr. Dawson asked whether I had considered Dr. Apolo's current cabozanatinib clinical trial. I told her that Dr. Apolo and I had discussed it, and that the preliminary results did not appear to be as compelling as those for MPDL3280a, and the side effects were much more serious.

We discussed other clinical trials involving anti-PD-L1 drugs that were also available to me. She said that a number of companies were studying those drugs: Merck has pembrolizumab (MK-3475) that is in a Phase III trial for metastatic bladder cancer (No. NCT02256436). Bristol-Myers Squibb has nivolumab (BMS-936558) that is in a Phase 1/2 trial at Johns Hopkins for metastatic bladder cancer (No. NCT01928394). Dr. Apolo is planning a Phase I trial for nivolumab and cabozantinib on bladder cancer patients (No. NCT02308943), but that is not yet open. CureTech is working on pidilizumab, which is being studied for lymphoma and myeloma, but is not in any clinical trials for metastatic bladder cancer.

Dr. Dawson said that she would email Dr. Rosen and MSKCC to determine whether he was in fact running a trial relating to PD-L1. I will email Drs. Apolo and Aragon-Ching and get their thoughts. My initial thoughts are that I'll roll the dice and with the MPDL3280a trial and see if I'm randomized into the immunotherapy arm. If so, I'll do it. If not, I'll decide whether to get the taxene chemo, or stall while I look into either the Merck or Bristol-Myers trials relating to PD-L1.

In almost unrelated news, this afternoon I received an email from Dr. Agarwal's nurse, reporting on the results of the samples he took from my neobladder during the cystoscopy:

Good news, the pathology from your recent procedure looked fine – no sign of tumor. Likewise, Dr. Agarwal did not see any strictures, lesions, or any other obvious source of the bleeding you’ve been experiencing.If you’d like to further discuss the results with Dr. Agarwal or myself, just let us know!

 Good news there, at least.