I believe that's the point, or at least should be.
One patient showing 'signs' of tumor regression reported informally during an investors' conference isn't exactly substantial or convincing evidence, esp without any details whatsoever.
It's better than nothing but it shouldn't change your investment thesis much if any.
What if the shrinkage was at 30mg/m^2 and was about 10%? It wouldn't mean anything and I would hope that the company wouldn't announce it. On the other hand if there was a trend going from stabilization to shrinkage as dosage increased that would be another thing entirely.
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