XOMA - One more note (a setup for interpreting EOA data). Having read multiple previous failed attempts to treat EOA it is pretty clear we don't know with much confidence what "healing EOA" looks like on a scan. Multiple trials with 'positive' scan data - but null or, often, meaningfully worse patient symptoms.
With that said - what I'd look for is strong data (low p value - e.g. 0.001) in one or more of the 'typical' EOA metrics (about 10ish - but then with multiple possible subgroups like symptom responders, joints with baseline palpable swelling, ...). If they used MRI for all patients (their presentations are not irrefutably clear on this) that may to be possible since MRI has such high fidelity wrt various parameters relating to EOA.