Monday, Mesoblast Limited ( MESO ) announced that the FDA supports an accelerated approval pathway for rexlemestrocel-L, its allogeneic mesenchymal precursor cell product, for end-stage ischemic heart failure with reduced ejection fraction (HFrEF) and a left ventricular assist device (LVAD). 

In the placebo-controlled LVAD-MPC Study #2, 70 patients with end-stage ischemic HFrEF were randomized at the time of LVAD implantation surgery to either a single intervention with rexlemestrocel-L (150 million STRO3-immunoselected and culture-expanded allogeneic cells) or placebo injected directly into the left ventricular myocardium. Key findings were:

Ischemic controls were characterized by persistently elevated levels of the inflammatory cytokine IL-6, by reduced ability to be weaned from LVAD support, and by high mortality.

In contrast, in ischemic patients treated with rexlemestrocel-L, IL-6 levels returned to normal by two months and remained low through 12 months.

63% of ischemic patients who received a single administration of rexlemestrocel-L successfully underwent temporary weaning from full LVAD support as early as month two, compared with 36% of controls (p = 0.008).

The cumulative incidence of successful temporary weans off the LVAD device over six months was also increased by 1.55-fold over control in ischemic patients who received rexlemestrocel-L.

Only 4.9% of ischemic patients treated with a single administration of rexlemestrocel-L died from month 2 through month 12, as compared with 26.9% of ischemic controls, an 82% reduction (p = 0.02).

Mesoblast intends to request a pre-BLA meeting with the FDA to discuss data presentation, timing, and FDA expectations for an accelerated approval filing in end-stage ischemic HFrEF patients with LVAD implantation.

Every year in the U.S., over 100,000 patients progress to end-stage HFrEF. In these patients, more than 2,500 life prolonging LVADs are implanted in the U.S. annually, of whom approximately 80% undergo the procedure as destination or permanent therapy.

Price Action: MESO shares are up 17.2% at $2.52 during the premarket session on the last check Monday.