Clinical Trial Outcomes: Mesoblast's lead product candidates, particularly rexlemestrocel-L for chronic heart failure, depend on successful completion and positive data from ongoing or planned clinical trials to demonstrate efficacy and safety sufficient for regulatory approval.

Regulatory Approval Uncertainty: Despite positive clinical data in some indications, securing final marketing authorization from health authorities like the FDA remains challenging, as evidenced by past conditional rejections or requests for additional data, which can delay or prevent commercialization.

Commercialization and Market Adoption: Even if regulatory approval is obtained, successfully launching and gaining significant market penetration for novel cell therapies in competitive therapeutic areas requires substantial commercial infrastructure, effective marketing strategies, and favorable reimbursement policies, which may not be achievable.