We are living in an age of disruptive information technology, driven by a relentless series of iterative advances. Blockbuster gives rise to Netflix. A cash-based society is replaced by cash-less apps. The local mall tries to meet the Amazon challenge. And all of the above are accessed by your new iPhone 12.
And so it is with biotechnology. Never has this been clearer than in reviewing the sordid history of cell-based therapy for heart disease (Figure 1) (1- 9).
While initially couched as disruptive, many of the studies turned out to be false, ambiguous, and/or premature. Upon careful review, the field has gone through a sequential series of scientific mis-steps, that, in retrospect, primarily relate to basing the therapeutic payload on non-cardiogenic cells and failing to address the issues of optimizing cell delivery, survival, grafting, scalability, and safety. A series of new technologies will be needed to reverse advanced heart failure, which remains a growing, world-wide unmet medical need. In short, it has been easier to rationalize than realize stem cell therapeutics. Nevertheless, as the old Dylan lyric goes, “the times they are a-changin’.“
In our NBT perspective (1), we outlined a daunting series of scientific and technical hurdles that must be met to unlock the therapeutic potential of heart stem cell therapy (Table 1). In the past 18 months, there have been dramatic scientific, medical, and financial advances which suggest that the field may be on the verge of an inflection point, driven by core advances in the biotechnology of human pluripotent stem cells. On the scientific level, general proof of concept that human embryonic stem (ES) cell derived cardiomyocytes can graft and reverse dysfunction in the heart post MI has been established (7). These studies raise the query of how to tackle the scalability challenge, given the need for injecting billions of cells into the heart; most of which will not survive the initial implantation and do not migrate or expand past the initial injection site. Problems of life-threatening arrhythmogenesis remain (10), as well as devising optimal approaches for percutaneous catheter-based delivery that meet strict safety and efficiency criteria. Custom device technology is likely to intersect with stem cell therapeutics to address this critical barrier. With regard to scalability, advances in 3D culture and-or robotics have allowed massive expansion of other differentiated cell types from human pluripotent stem cells (beta islet, dopaminergic, etc.) that are coming online.
For the past 7 years, our labs at Karolinska Institutet (KI; Chien) and AstraZeneca (AZ; RFD) have been working on vascular regeneration by translating work initially done in mice (11) to large animals (12) and onward to First Time in Human (FTIH) studies, that were published in Nature Communications (13) just shortly before our NPG piece. At the time, our collective thinking already was beginning to turn to heart muscle cell regeneration, based on a long series of studies spanning 15 years based on the discovery of multipotent heart progenitors that build the heart in all mammalian species (Figure 2)(14-19). Subsequently independent labs, most notably the Menasche lab have taken this further toward studies in primates (20) and a single case study in patients (21). Right before our NBT perspective was published, we established a joint effort to unlock the therapeutic potential of human ventricular heart progenitors derived from human ES cells to reverse heart failure (22-23), based on work at KI that established their potential scalability and efficacy (9). As the thinking goes, perhaps the heart progenitor would have inherent advantages over the fully differentiated cardiomyocyte in terms of generation time, ability to expand following in vivo grafting, viability, migration beyond the site of needle injection, and in integration to the native myocardium and maturing in a more normal manner without triggering ventricular tachycardia, a life threatening side effect found with all the studies employing differentiated human induced pluripotent stem cells (iPS) or ES derived cardiomyocytes. Notably, in the setting of cell therapy for Parkinsons, the projected clinical cellular payload has been proposed to be dopaminergic progenitor cells, as it appears that they may have the most potential to reconnect to the native neural circuitry.
In addition to our own work, the field of cell based therapy, initially spurred by chimeric antigen receptor T (CAR T) cell therapy for cancer, is beginning to take hold for regenerative therapeutics in general. Semma Therapeutics is merged with Vertex, and driving forward with beta islet cells for diabetes. Bluerock has been acquired by Bayer and late stage planning of dopaminergic neuronal progenitors for Parkinsons. Astellas is moving forward with human iPS derived retinal pigmental cells for eye diseases. A single case study suggests long term safety of autologous iPS derived cell based therapy for Parkinsons (24). Novo Nordisk A/S and Karolinska Institutet have entered into a collaboration to produce a cellular therapy, from human embryonic stem cells, for treating dry macular degeneration. Newcos fostering larger scale production of ES or iPS derived differentiated cell types, including Vicardiomyocytes, have now found funding. GMP cell production facilities are sprouting up due to the documented efficacy of CAR T cell therapeutics for blood diseases, and a host of next generation technologies are moving forward to advance these to non-autologous iPS derived natural killer (NK) cells, as well as the development of adjunctive therapies that could extend efficacy to solid tumors.
For the CVRM field, the future is likely to go beyond human ventricular progenitors (HVPs) to encompass other unmet clinical needs (25). Despite recent advances in reducing the morbidity and mortality of cardiovascular, renal and metabolic diseases such as the approvals of SGLT2 inhibitors, there is currently no therapy which stops disease progression. CVRM diseases are degenerative and the only curative option today is organ transplantation, an option for few patients due to the lack of donor organs. Recent advances in the science behind renal and liver regeneration are additional areas where cell therapy is likely to play a key role in the future.
In the past 18 months since the publication of our NBT Perspectives (1) and the “About the Paper” follow-up (26), we have been able to progress the HVP project closer to IND and towards “first-in-human studies” (Table 1). Nevertheless, many challenges remain that will ultimately require a host of new discoveries, including tackling the issues of immunosuppression, graft rejection and graft-versus-host complications, limiting batch-to-batch variations in cell production, identification of graft allo-antigens and subsequent approaches to tolerization, generation of potential universal cell lines, development of surrogate indices of early efficacy and safety in Phase 1-2 studies, and optimizing the cost-of-goods to allow widespread access to the therapeutic worldwide. Undoubtedly, by working together, the next generation of physicians-scientists-inventors-entrepreneurs, will be well-positioned to write a future NBT Perspectives on Heart Regeneration 9.0.
- Regenerating the field of cardiovascular cell therapy. Chien KR, Frisén J, Fritsche-Danielson R, Melton DA, Murry CE, Weissman IL.Nat Biotechnol. 2019 Mar;37(3):232-237. doi: 10.1038/s41587-019-0042-1. Epub 2019 Feb 18.PMID: 30778231
- Myoblast transplantation for heart failure. Menasché P,et al.Lancet. 2001 Jan 27;357(9252):279-80. doi: 10.1016/S0140-6736(00)03617-5.PMID: 11214133
- Transplantation of Progenitor Cells and Regeneration Enhancement in Acute Myocardial Infarction (TOPCARE-AMI). Assmus B, et al.Circulation. 2002 Dec 10;106(24):3009-17. doi: 10.1161/01.cir.0000043246.74879.cd.PMID: 12473544
- A randomized, double-blind, placebo-controlled, dose-escalation study of intravenous adult human mesenchymal stem cells (prochymal) after acute myocardial infarction. Hare JM,et al.J Am Coll Cardiol. 2009 Dec 8;54(24):2277-86. doi: 10.1016/j.jacc.2009.06.055.PMID: 19958962
- Administration of cardiac stem cells in patients with ischemic cardiomyopathy: the SCIPIO trial: surgical aspects and interim analysis of myocardial function and viability by magnetic resonance. Chugh AR, et al. 2012 Sep 11;126(11 Suppl 1):S54-64. doi: 10.1161/CIRCULATIONAHA.112.092627.PMID: 22965994
- Intracoronary cardiosphere-derived cells for heart regeneration after myocardial infarction (CADUCEUS): a prospective, randomised phase 1 trial. Makkar RR,et al. Lancet. 2012 Mar 10;379(9819):895-904. doi: 10.1016/S0140-6736(12)60195-0. Epub 2012 Feb 14.PMID: 22336189
- Human embryonic stem cell-derived cardiomyocytes restore function in infarcted hearts of non-human primates. Liu YW,et. al.Nat Biotechnol. 2018 Aug;36(7):597-605. doi: 10.1038/nbt.4162. Epub 2018 Jul 2.PMID: 29969440
- Transplantation of Human Embryonic Stem Cell-Derived Cardiovascular Progenitors for Severe Ischemic Left Ventricular Dysfunction. Menasché P,et. al.J Am Coll Cardiol. 2018 Jan 30;71(4):429-438. doi: 10.1016/j.jacc.2017.11.047.PMID: 29389360
- Human ISL1+ Ventricular Progenitors Self-Assemble into an In Vivo Functional Heart Patch and Preserve Cardiac Function Post Infarction. Foo KS,et. al.Mol Ther. 2018 Jul 5;26(7):1644-1659. doi: 10.1016/j.ymthe.2018.02.012. Epub 2018 Feb 17.PMID: 29606507
- Human Embryonic Stem Cell-Derived Cardiomyocytes Regenerate the Infarcted Pig Heart but Induce Ventricular Tachyarrhythmias. Romagnuolo R, et al. Stem Cell Reports. 2019 May 14;12(5):967-981. doi: 10.1016/j.stemcr.2019.04.005. Epub 2019 May 2.PMID: 31056479
- Modified mRNA directs the fate of heart progenitor cells and induces vascular regeneration after myocardial infarction. Zangi L,et al.Nat Biotechnol. 2013 Oct;31(10):898-907. doi: 10.1038/nbt.2682. Epub 2013 Sep
- Biocompatible, Purified VEGF-AmRNA Improves Cardiac Function after Intracardiac Injection 1 Week Post-myocardial Infarction in Swine.Carlsson L, et al. Mol Ther Methods Clin Dev. 2018 Apr 10;9:330-346. doi: 10.1016/j.omtm.2018.04.003. eCollection 2018 Jun 15.PMID: 30038937
- Intradermal delivery of modified mRNA encoding VEGF-A in patients with type 2 diabetes. Gan LM,et al.Nat Commun. 2019 Feb 20;10(1):871. doi: 10.1038/s41467-019-08852-4.PMID: 30787295
- Postnatal isl1+ cardioblasts enter fully differentiated cardiomyocyte lineages. Laugwitz KL, et al 2005 Feb 10;433(7026):647-53. doi: 10.1038/nature03215.PMID: 15703750
- Multipotent embryonic isl1+ progenitor cells lead to cardiac, smooth muscle, and endothelial cell diversification. Moretti A,et al . 2006 Dec 15;127(6):1151-65. doi: 10.1016/j.cell.2006.10.029. Epub 2006 Nov 22.PMID: 17123592
- The renewal and differentiation of Isl1+ cardiovascular progenitors are controlled by a Wnt/beta-catenin pathway. Qyang Y,et al.Cell Stem Cell. 2007 Aug 16;1(2):165-79. doi: 10.1016/j.stem.2007.05.018. Epub 2007 Jun 14.PMID: 18371348
- Human ISL1 heart progenitors generate diverse multipotent cardiovascular cell lineages. Bu L, et al. 2009 Jul 2;460(7251):113-7. doi: 10.1038/nature08191.PMID: 19571884
- Generation of functional ventricular heart muscle from mouse ventricular progenitor cells. Domian IJ, et al. 2009 Oct 16;326(5951):426-9. doi: 10.1126/science.1177350.PMID: 19833966
- Superselective endovascular tissue access using trans-vessel wall technique: feasibility study for treatment applications in heart, pancreas and kidney in swine.Grankvist R. et al. J Intern Med. 2019 Apr;285(4):398-406. doi: 10.1111/joim.12841. Epub 2018 Oct 28.PMID: 30289186
- A purified population of multipotent cardiovascular progenitors derived from primate pluripotent stem cells engrafts in postmyocardial infarcted nonhuman primates. Blin G, et al J Clin Invest. 2010 Apr;120(4):1125-39. doi: 10.1172/JCI40120. Epub 2010 Mar 24.PMID: 20335662
- Human embryonic stem cell-derived cardiac progenitors for severe heart failure treatment: first clinical case report. Menasché P, et al .Eur Heart J. 2015 Aug 7;36(30):2011-7. doi: 10.1093/eurheartj/ehv189. Epub 2015 May 19.PMID: 25990469
- Personalized iPSC-Derived Dopamine Progenitor Cells for Parkinson's Disease. Schweitzer JS, et al N Engl J Med. 2020 May 14;382(20):1926-1932. doi: 10.1056/NEJMoa1915872.PMID: 32402162