Ann: Mesoblast Phase 3 Chronic Low Back Pain Results, page-312

It's a bit unclear just what will happen with Grunenthal, but it seems clear it won't happen quickly. Here is the language re: milestone payments from the announcement back in 2019:

Mesoblast will receive up to US$150 million in upfront and milestone payments prior to product launch, as well as further commercialisation milestone payments. These payments include commitments up to US$45 million within the first year comprising US$15 million on signing, US$20 million on receiving regulatory approval to begin a confirmatory Phase III trial in Europe, and US$10 million on certain clinical and manufacturing outcomes. Cumulative milestone payments could exceed US$1 billion depending on the final outcome of Phase III studies and patient adoption. Mesoblast will also receive tiered double digit royalties on product sales.
...
Grünenthal and Mesoblast have agreed on an overall development plan for MPC-06-ID to meet European regulatory requirements. As part of this plan, the companies will collaborate on the study design for a confirmatory Phase III trial in Europe. The results of the two Phase III trials are expected to support both U.S. FDA and European EMA regulatory approvals for MPC-06-ID in chronic low back pain due to degenerative disc disease.

We don't know what the "certain clinical and manufacturing outcomes" may be, but presumably, none of them are yet operative, as I think we would have heard SI touting that pretty heavily.

So the next step with Grun will be putting together the application for regulatory approval of a Phase III European trial. Upon approval from the EU, a cheeky $20 million will be added to MSB's coffers. Those other unspecified conditions could lead to an extra $10 million.

Should be a very good chance that we will get a similar partnership agreement with a US pharma in the near future, and perhaps even more likely, FDA guidance on what their expectations are for either potential approvals and/or additional trials. Clearly, approval would be the best for us here, but perhaps a joint US-EU confirmatory Phase III is more likely, given the mixed results. Maybe we will hear that the Phase III results point to a more direct approval path in Europe, too (though seems not).

Overall, what does seem clear is that it's time for MSB and Grun to get down to work on designing that next trial and for MSB to get its a*s to the FDA, PRONTO to point a way forward out of the opioid epidemic.

Either way, for any new trials, I doubt we will have the same issues with missed primary endpoints this time...