From presentation and interview given by Sznol at ASCO:
Published: Wednesday, June 05, 2013
Melanoma: Long
Overall Survival in Patients Receiving Nivolumab
BY
RABIYA S. TUMA, PHD
Favorable One- and Two-Year
Survival Rates
A total of 107 patients with
metastatic melanoma enrolled in the trial, which was led by
Mario Sznol, MD, Professor of Medical Oncology at Yale Cancer Center. To
be eligible, patients had to have had at least one prior therapy but no
more than four for advanced disease and no prior treatment with ipilimumab.
Patients received intravenous nivolumab every two weeks at a dose of 0.1 to
10 mg/kg.
The patients had a median age of
61.... the
group was heavily pretreated, with 66 percent of patients having had at
least two prior therapies and 25 percent, three or more.
Additionally, 78 percent of patients had visceral metastases and 36 percent
had elevated lactate dehydrogenase, which is associated with a poorer
outcome.
The investigators saw no dose
limiting toxicities. (With all the usual side effects I've already mentioned.)
"There was no additional
safety signal seen with the additional year of follow-up," Sznol said.
The overall response rate was 31 percent across all doses, with no apparent
dose response. The median duration of response was two years and 45 percent
of the responders showed a response at the first tumor assessment at eight
weeks, indicating that the responses can be both rapid and durable.
Moreover, 12 of 17 patients who
went off drug for reasons other than disease progression continued to
respond for at least 16 weeks, and eight of those were continuing response
at the time of the data analysis (range of 16 to 56 weeks). "You don't
need continued treatment in a subset of patients in order to maintain
response," Sznol said.
Pointing to the Kaplan-Meier
curve for progression-free survival, he noted that the curve dropped
rapidly at first but then flattened out. "Although the median
progression-free survival of 3.7 months is not overly impressive, the one-
and two-year progression-free survival rates of 36 and 27 percent
are," Sznol said.
The median overall survival for
the study group is 16.8 months. The one-year estimated overall survival
rate is 62 percent and the two-year rate is 43 percent. With a median
follow-up of 22 months (range 14 to 51 months), 47 patients remain alive.
[When] asked about the optimal duration of treatment with nivolumab. Sznol
said the optimal duration remains unclear, but that his group at Yale have
discontinued therapy on two patients with near complete responses, one after
three cycles and the other after five cycles. Neither patient has relapsed.
"So at least at complete
responders, you probably don't need to continue the drug," he said.
"The question is, what do you do in patients with stable disease or
partial response. Do you continue to give them drug every two weeks or do
you decrease the interval of dosing? I don't think we have an answer to
that question."
[When] asked if
it was possible to biopsy lesions in responders to see if the lesions
really contain residual disease. "I think the rate of complete
response here is a little bit underestimated," Sznol responded.
"Of the five patients we treated at Yale who are responders, four are
complete responders or near-complete responders and the fifth patient, who
has a liver nodule, is PET negative.
“So there wasn't much for us to
biopsy in our long-term responders. We have biopsied a few patients with
progressive disease, but we haven't analyzed that tissue yet."
Brain Metastases?
...Asked about the likelihood that the drug works on brain metastases. Sznol
noted that this trial excluded patients with active brain lesions, but
accepted patients with previously-treated central nervous system tumors.
Therefore the answer to the question remains unknown. "But we have
long-term responders who didn't develop any brain metastases, so that
suggests that maybe we are controlling disease in the brain," he said.
There are now three ongoing
Phase III trials testing nivolumab in patients with metastatic melanoma. A
trial testing the drug in patients with brain metastases has been proposed,
but Sznol said he did not know if it was approved or would go forward.
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I think this is promising, but you are right. It would be really nice to have a longer response than two years, and why not let others into the study. They really have nothing to lose, but they could have the opportunity to pioneer some studies!
ReplyDeleteSounding pretty good! They just have to continue moving forward with this!
ReplyDeleteseems they are definitely on the right track...just need to know what makes one a complete responder and another not...
ReplyDeleteMy husband is doing IPI and PD 1 trial through a local hospital. He is on the IPI first, we can't see any growth on the cancer on the outside really but we are so hoping it does not spread before trying the PD1. that is really what he wanted to receive first but on trials its the luck of the draw. I wish we could get more than 2 years but that is better than just 4-5 months!
ReplyDeleteI hope he does well. The combo...regardless of order....is thought by some to offer the very best chance of success! Hang in there!
ReplyDelete