Phase III chronic lower back pain primary end point

.So,
it seems with the recent announcements people have been very critical of the primary end points chosen by mesoblast in both heart failure and covid ARDS AFTER the results were released, as if like we never knew or had access to knowing what it was before hand. So let’s all begin discussing the chosen primary end point in lower back pain trial BEFORE the release of results. From what I understand, mesoblast want to see:

a primary endpoint that comprises of both pain relief and improved function, consisting of a 50% reduction in lower back pain as measured by visual analog score and a 15 point improvement in owestry disability index with NO additional interventions.

i have provided links to the visual analog score and owestry disability index below

these patients have likely failed epidural steroid therapy and are on the cusp of requiring surgery (this again is not a primary intervention in the trial, it is a salvage therapy).

what do we think the likelihood of passing this is? I was looking at the successful trial of tanezumab phase three which inhibits nerve growth, which is something that has been observed when administering our stem cells or at least recession of the nerve growth at the site of injury. Let’s have a look at their primary end points for comparison also

visual analog score

owestry disability index
https://www.worksafe.qld.gov.au/__data/assets/pdf_file/0014/23036/oswestry-low-back-disability-questionnaire1.pdf