Stem cells in the management of heart failure: what have we learned from clinical trials?

Abstract

Research shows that various types of stem cells (SCs) have the ability to rebuild damaged heart tissue. The TIME and Late TIME human trials shed light on the optimum timing of SC therapy administration after myocardial damage. The FOCUS study failed to show a substantial positive effect of bone marrow-derived mononuclear cells in patients suffering from ischemic heart failure; however, some completed human trials do show promise, with improvement in cardiac function. Recent clinical trials have identified a subset of marrow cells that was able to stimulate endogenous adult cardiac SCs where cardiac SCs administration showed promise in the SCIPIO trial. This review addresses some of the lessons learned from clinical trials with SC therapy in ischemic heart failure.

Keywords:

• cardiac function
• congestive heart failure
• hypertension
• ischemic heart failure
• myocardial infarction
• pharmacotherapy
• stem cell

Acknowledgements

We acknowledge J Samuel, PharmD, of the Albany College of Pharmacy and Health Sciences for initial discussions and literature searches on this topic. Editorial assistance was provided by K Keating, Pharmaceutical Research Institute, Albany College of Pharmacy and Health Sciences, Rensselaer, NY, USA.

Financial & competing interests disclosure

The authors received funding from the Pharmaceutical Research Institute at the Albany College of Pharmacy and Health Sciences, Albany, NY, USA. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties.

No writing assistance was utilized in the production of this manuscript.

Key issues

• A number of key issues still remain to be addressed in optimizing the efficacy and safety of the different stem cell (SC) therapies.

• Cardiac repair through the use of regenerative medicine has been a considerable research focus over the last decade.

• Several SC types have been investigated as potential candidates to target post-infarction heart failure.

• Different cell therapeutic approaches involve bone marrow-derived mononuclear cells and mesenchymal SCs, adipose tissue-derived SCs, cardiac-derived SCs, and cell combinations.

• Clinical trials employing mesenchymal SCs and cardiac-derived SCs have demonstrated efficacy in infarct size reduction and regional wall contractility improvement.

• The progression of investigation through the rigors of clinical trial design has provided some answers as to the potential clinical utility of SC therapies.

• Regarding delivery methods, the safety of catheter-based, transendocardial SC injection has been established plus other means of delivery are under investigation.

• Understanding the mechanisms underlying the therapeutic effects of the different SC therapies would allow for optimization of the approaches.

• Combinations of direct and indirect cell therapies are under investigation, and future studies will focus on determining the most efficacious cell type(s) and/or cell combinations.