The Mesoblast Limited (ASX: MSB) share price has plunged 43% after giving an update about its COVID-19 ARDS trial.
What happened?
As a reminder, Mesoblast conducted a randomised controlled trial of remestemcel-L in ventilator-dependent patients with moderate to severe acute respiratory distress syndrome (ARDS) due to COVID-19 infection after the Data Safety Monitoring Board (DSMB) performed a third interim analysis on the trial’s first 180 patients.
The trial was powered to achieve a primary endpoint of 43% reduction in mortality at 30 days for treatment with remestemcel-L on top of the highest level of care in a trial of 300 patients. This projected mortality reduction was based on pilot data observed during the initial stages of the pandemic when control mortality rates were exceedingly high and prior to new evolving treatment regimens that have reduced disease mortality in ventilated patients.
The DSMB reported that there were no safety concerns and noted that the trial is not likely to meet the 30-day mortality reduction endpoint at the planned 300 patient enrolment. The DSMB recommended that the trial complete with the currently enrolled 223 patients, and that all be followed-up as planned.
What now?
The trial has not yet accrued data on the secondary endpoints, which include days alive off mechanical ventilation at 60 days after randomisation, overall survival, days in intensive care and so on. Additionally, measures of circulating cytokines and inflammatory markers will be evaluated. None of these were included in the interim analysis. As such, the trial will evaluate all 223 enrolled patients through 60 days of follow-up to study potential treatment effects on these outcomes.
Mesoblast explained that numerous changes to the treatment of COVID-19 patients has occurred, including both before and while on mechanical ventilation that may have an effect on the mortality endpoint of the trial. All of these changes may have changed the natural course of ventilated patients and reduced overall mortality rates during the trial compared to the early stages of the pandemic.
Mesoblast and Novartis, which the ASX share has an agreement with, will both analyse these results to identify meaningful clinical outcomes that may guide decisions on the development program for remestemcel-L in non-COVID ARDS.
Summary thoughts
I’m not a medical expert, but clearly this has disappointed investors. I’m not much of a fan of investing in businesses that result in a binary outcome like this – it’s great or terrible – I prefer ASX growth shares where it’s much more likely to deliver a solid result for investors like Pushpay Holdings Ltd (ASX: PPH).
