They weren't trying to get results, only giving a low dose to verify acceptable side effects. Wait for the larger doses to render judgement on clinical results of the treatment modality itself.
I completely agree with you. If there was even one response I would be much more optimistic. Since there is no clinical signal this is at best a proof of concept and safety.
> Although the efficacy of the treatment was low, the researchers used relatively small doses of T cells to establish the safety of the approach, says Ribas. “We just need to hit it stronger the next time,” he says.