Thanks - I'd forgotten that you had done this analysis. So my point here is that TN is most likely a heterogenous group, and with 13 patients you may only have a couple of patients from each subgroup, or maybe not even that. A 10-15% response rate in this group might be enough for approval, so it makes no sense to abandon it on the basis of this trial.
I think they need a 200 or so patient Phase IIB trial in TN, stratified by HG. If the results are good, that could serve as a pivotal trial.