Select Excerpts from the Discussion

CD 1, Tracks 2, 4

DR LOVE: Tom, do you agree or disagree with the statement that for a patient who would have met the entry criteria for ECOG-E4599, the current standard of care is chemotherapy with bevacizumab?

DR LYNCH: Agree.

DR LOVE: Should bevacizumab be continued until disease progression?

DR LYNCH: Agree.

DR LOVE: Why do you feel that way?

DR LYNCH: If I’m going to practice evidence-based medicine, I’d want to treat my patients the way they were treated on ECOG-E4599 (Sandler 2005), until we have evidence that dictates otherwise. I also like the idea of continuing bevacizumab after finishing the chemotherapy because micrometastatic disease or smaller-volume disease might be present that you may be influencing.

DR LOVE: I’ll ask Alan the same questions.

DR SANDLER: The answers are yes and yes. It’s interesting that other clinical investigators don’t necessarily have the same thoughts. The objections raised include the fact that this is only one randomized Phase III study, and we’re waiting for a second. That is fair, and I usually reply, “Is anybody using erlotinib?”

Only one randomized Phase III study supports erlotinib (Shepherd 2005), and everybody has pretty much jumped on that one. I personally wouldn’t want to put a family member on a study that included a control arm without bevacizumab. More toxicity is associated with bevacizumab and chemotherapy than with chemotherapy alone, but I believe it’s clinically acceptable.

DR LOVE: What about bevacizumab and other chemotherapy agents?

DR LYNCH: I need to see data to suggest that you can safely administer bevacizumab with carboplatin/docetaxel and carboplatin/gemcitabine, but I suspect you can.

DR LOVE: Does “suspect” mean you’re comfortable with using it off protocol?

DR LYNCH: Last night, I was driving to the airport with a practicing oncologist who’s going to use carboplatin/docetaxel with bevacizumab. He said he has administered it to patients and had no problems. I expect that it will probably be okay. However, I won’t use it off protocol until I see some data suggesting it’s safe. I expect it will be safe, but I’ve stayed with carboplatin/paclitaxel until we have some of the initial data, which we’ll have very soon.

DR LOVE: Ed, specifically which chemotherapy regimens are you using with bevacizumab?

DR KIM: At MD Anderson, we’re enrolling patients in a trial of carboplatin/ docetaxel and bevacizumab. We have about 14 patients on the trial, and we haven’t seen many serious toxicities. We had one person with hemoptysis who had an adenocarcinoma, a noncavitary lesion.

It wasn’t in the mediastinum, but it was more centrally located. It was an incidental hemoptysis that occurred, and we took him off the study.

It was interesting because the tumor response was cavitary. We also had one person who had febrile neutropenia, but you expect some of that with chemotherapy alone.

DR LILENBAUM: It’s the gemcitabine-based doublets that remain somewhat worrisome. I believe most people feel comfortable using docetaxel as opposed to paclitaxel. Many people have done it safely. I’m not sure why it should be a concern.

Gemcitabine is more of a concern. We are doing a Phase II study of oxaliplatin and gemcitabine with bevacizumab. We haven’t seen any significant complications, such as bleeding or thrombocytopenia, or more episodes of febrile neutropenia than expected. So I expect it to turn out okay. The best evidence for that is that in an NCI Phase III adjuvant study, a setting in which you want to be extra careful about toxicities, most people felt comfortable including a gemcitabine-based regimen.

DR HERBST: I believe one of the reasons people feel comfortable is that the registration trial in Europe, evaluating bevacizumab with chemotherapy, is being conducted with gemcitabine combinations. Although those data are talked about, we haven’t seen them, but one would assume that people have considered that database as they’ve gone forward. My feeling is that we can probably use all the combinations, but I agree that we need to see the data.

CD 1, Track 6

DR LOVE: Roy, can you comment on the mechanism of action of bevacizumab?

DR HERBST: We really don’t know. Is it working by enhancing chemotherapy? That’s one thought. Is it working to increase drug delivery? Probably. Is it working directly on tumor cells? Data suggest that tumor cells have VEGF receptors. Is it working in the maintenance setting to suppress angiogenesis and endothelial and tumor cells? Because we have many more compounds coming down the pike, we need to do some mechanistic studies.

CD 1, Tracks 11-12

DR LOVE: Tom, when you start a patient on chemotherapy and bevacizumab in the first-line metastatic setting, what do you tell them about the risks?

DR LYNCH: I tell them that their risk of dying from chemotherapy increases from about one percent to about three to four percent, but I emphasize that the overall risk of dying from the disease will be reduced. In the end, the chance of living longer will be greater on chemotherapy combined with bevacizumab.

We talk about hemoptysis and the fact that it’s rare but can still happen. We also talk about stroke and other thromboembolic phenomena. When we consider the colorectal experience with bevacizumab, we’re all pretty confident that bevacizumab is associated with a real but small increase in thromboembolic phenomena, which is not trivial for patients with lung cancer.

I believe that in the end, what drives our enthusiasm for bevacizumab is the fact that in a trial of patients with Stage IV disease, it demonstrated a substantial and clinically meaningful prolongation of survival (Sandler 2005). This is why I believe all of us here would endorse using it in this setting. You have to inform your patient about the risks, and I believe most patients will decide it’s worth it.

DR LOVE: It’s been said that perhaps hemoptysis is a manifestation of response. Can you comment on that?

DR SANDLER: My bias, particularly for the squamous cell histology, is that it may be a manifestation of a brisk response to treatment and that cavitation ultimately results.

CD 1, Track 14

DR LOVE: Roy, can you discuss findings from the trial combining bevacizumab with erlotinib that was presented at ASCO 2006?

DR HERBST: A randomized Phase II trial of 120 patients was reported by Lou Fehrenbacher from Kaiser at ASCO. The treatment arms included chemotherapy (docetaxel or pemetrexed) with placebo or bevacizumab versus bevacizumab with erlotinib. In this second-line setting, bevacizumab enhanced both the EGFR inhibitor, erlotinib, and chemotherapy (Fehrenbacher 2006).

The results were reasonably good regarding time to progression, but the numbers were small. The hazard ratios were 0.66 for chemotherapy in combination with bevacizumab and 0.72 for erlotinib in combination with bevacizumab. The 95 percent confidence intervals crossed one. So these were not statistically significant data, but they were suggestive of a trend. Toxicity and drug discontinuation due to adverse events were much less frequent among the patients who received the less toxic erlotinib/bevacizumab combination (Fehrenbacher 2006).

CD 1, Track 17

DR LOVE: Outside of a clinical trial, have you used or would you consider using bevacizumab for a patient with previously treated brain metastases?

DR LYNCH: No. We’re participating in the trial to answer that question. Patients have their brain metastases radiated first, and then they receive treatment. Because of the restrictions in eligibility for ECOG-E4599, I believe we have to follow an evidence-based approach, and I have not been using bevacizumab in this setting outside of a protocol.

DR LOVE: What about resected brain metastases?

DR LYNCH: Resected brain metastases would not have been included in ECOG-E4599.

DR MILLER: Aren’t we amending the current clinical trials to allow patients with previously radiated brain metastases? These contraindications have relative degrees. Certainly squamous histology and hemoptysis are much more powerful contraindications (Gordon 2001). This drug is very active in patients with glioblastoma multiforme — huge tumors with lots of edema — and we’re undertaking approval strategy trials for those patients. We usually obtain the blessing of a neurologist to use bevacizumab, but we certainly have done it.

DR HERBST: I would wait until the data are available, which I expect will be soon. One trial, called PASSPORT, will determine if you can use chemotherapy with bevacizumab for patients with previously treated brain metastases.

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