“Immunotherapy for gastric cancer” take 3.
The Study: Stuck in phase 2, at least in the West. This fall the phase 3 trial ATTRACTION-2 demonstrated a “significant” one month survival advantage among Asian patients treated with third- (or more) line nivolumab versus...placebo. On this side of the globe, pembrolizumab has now followed suit of nivo (plus ipi, of course) and avelumab with its own phase 2 trial KEYNOTE-059 reported last week. 259 patients with EGJ and gastric cancers failing at least two previous regimens received single arm pembro until progression. 30 (12%) achieved a "durable" response (lasting at least 2 months) while 46 (18%) experienced grade 3 to 5 toxicities, including two treatment-related deaths. That's a pretty rough response to toxicity ratio, similar to other immunotherapies evaluated single arm in this setting. Including the part about improved response rates (RR) among those with >1% PD-L1 expression, which was associated with a 23% RR here. We await official reporting of several phase 3 components that actually compare these agents to chemo, but it ain’t lookin' good for avelumab or pembro. Nivo, on the other hand, is taking its shot at debuting first-line.
Bottom Line: We still don’t know which treatment is best for your patient with advanced gastric cancer who fails a standard taxane-containing regimen, but it’s not for lack of trying. | Fuchs, JAMA Oncol 2018