Human embryonic and induced pluripotent stem cells in clinical trials.

BACKGROUND: Human embryonic and induced pluripotent stem cells (hESC and hiPSC) have tremendous potential for clinical implementation. In spite of all hurdles and controversy, clinical trials in treatment of spinal cord injury, macular degeneration of retina, type 1 diabetes and heart failure are already ongoing. SOURCES OF DATA: ClinicalTrials.gov database, International Clinical Trials Registry Platform, PubMed and press releases and websites of companies and institutions working on hESC- and iPSC-based cellular therapy. AREAS OF AGREEMENT: The initial results from multiple clinical trials demonstrate that hESC-based therapies are safe and promising. AREAS OF CONTROVERSY: Are iPSC cells safe in the clinical application? Is there a room for both hESC and iPSC in the future clinical applications? GROWING POINTS: Increasing number of new clinical trials. AREAS TIMELY FOR DEVELOPING RESEARCH: Development of hESC- and/or iPSC-based cellular therapy for other diseases.