StemCell Therapy

This case study was developed as one of a set of three studies, focusing on somewhat mature but rapidly evolving technologies. These case studies are intended to draw out lessons for the development of a cross-sectoral governance framework for emerging technologies in health and medicine. The focus of the case studies is the governance ecosystem in the United States, though where appropriate, the international landscape is included to provide context. Each of these case studies:

Each case study begins with two short vignettes designed to highlight and make concrete a subset of the ethical issues raised by the case (seeBox 1andBox 2). These vignettes are not intended to be comprehensive but rather to provide a sense of the kinds of ethical issues being raised today by the technology in question.

The cases are structured by a set of guiding questions, outlined subsequently. These questions are followed by the historical context for the case to allow for clearer understanding of the trajectory and impact of the technology over time and the current status (status quo) of the technology. The bulk of the case consists of a cross-sectoral analysis organized according to the following sectors: academia, health care/nonprofit, government, private sector, and volunteer/consumer. Of note, no system of dividing up the world will be perfectthere will inevitably be overlap and imperfect fits. For example, government could be broken into many categories, including international, national, tribal, sovereign, regional, state, city, civilian, or military. The sectoral analysis is further organized into the following domains: science and technology, governance and enforcement, affordability and reimbursement, private companies, and social and ethical considerations. Following the cross-sectoral analysis is a broad, nonsectoral list of additional questions regarding the ethical and societal implications raised by the technology.

The next section of the case is designed to broaden the lens beyond the history and current status of the technology at the center of the case. The Beyond section highlights additional technologies in the broad area the focal technology occupies (e.g., neurotechnology), as well as facilitating technologies that can expand the capacity or reach of the focal technology. The Visioning section is designed to stretch the imagination to envision the future development of the technology (and society), highlighting potential hopes and fears for one possible evolutionary trajectory that a governance framework should take into account.

Finally, lessons learned from the case are identifiedincluding both the core case and the visioning exercise. These lessons will be used, along with the cases themselves, to help inform the development of a cross-sectoral governance framework, intended to be shaped and guided by a set of overarching principles. This governance framework will be created by a committee of the National Academies of Sciences, Engineering, and Medicine (https://www.nationalacademies.org/our-work/creating-a-framework-for-emerging-science-technology-and-innovation-in-health-and-medicine).

Regenerative medicine as a field is quite broad but is generally understood to focus on the regeneration, repair, and replacement of cells, tissues, and organs to restore function (Mason and Dunnill, 2008). The aspect of regenerative medicine on which this case study focuses relates to the ability to treator curegenetic hematologic disease safely and effectively, and the significant trade-offs that come with these novel therapies.

The story of this therapy begins in the history of bone marrow transplants. The medicinal value of bone marrow has long been recognized and was first discussed in the 1890s as a potential treatment (administered orally) of diseases believed to be characterized by defective hemogenesis (Quine, 1896).

While allogeneic bone marrow transplant (in which stem cells from a donor are collected and transplanted into the recipient) may be the most broadly known form of hematopoietic stem and progenitor cell (HSPC) transplant, a range of other cell types are also used. HSPCs used in transplant can be either allogeneic (i.e., from a donor) or autologous (i.e., from the person who will also receive the transplant). The cells used in transplant research and clinical care can come from bone marrow, peripheral blood stem cells (PBSCs), umbilical cord blood, and pluripotent stem cell-derived cells.

A major challenge throughout the history of HSPC transplantation has been the dire risks associated with these transplants, including the morbidity and mortality caused by immunological reactions between the transplanted cells and the tissues of the recipient. In particular, graft-versus-host disease (GVHD) is a serious response in which the transplanted stem cells view the recipients tissues as foreign and mount an immune response, attacking the recipients body. If an autologous transplant is not possible given the nature of the disease to be treated, an immunologically well-matched healthy donor for allogeneic transplant is critical. For genetic hematologic disease, a new approach that would not only treat but cure the condition is now being tested: genetic modification of the patients own HSPCs to correct or compensate for the defect, followed by transplantation of the corrected autologous cells.

This challenge of matching transplantable cells to patients has driven evolution within the field of regenerative medicine, including logistical fixes in the form of HSPC registries and banks to technological approaches including the use of pluripotent stem cell-derived cell sources and genome editing (e.g., clustered regularly interspaced short palindromic repeats [CRISPR]).

This challenge of immunological matching has also driven significant ethical challenges, even beyond the substantial risks of HSPC transplantation itself. In contrast to many novel technologies, where finances are a primary barrier to access, in the case of regenerative medicine, there is the additional barrier of biology. People who are not of European descent have a lower probability of finding well-matched donors than do people of European descent. Furthermore, genetic hematologic diseases like sickle cell disease (SCD) and thalassemia, for which HSPC transplant is the only established cure (and a fraught one, at that), have struggled to garner the financial and grant support needed to move research forward. This challenge persists despite SCD being three times more prevalent in the United States than cystic fibrosis, which has historically benefited from generous public and private funding (Farooq et al., 2020; Wailoo and Pemberton, 2006). All of this stands on a background of long-understood barriers even to standard of care (e.g., adequate pain management) for individuals with SCD in particular (Haywood et al., 2009). Together, these facts raise concerns related to equity and access at multiple stages of research, development, and clinical care.

Finally, advances in this science have also attracted the attention of those who are willing to take advantage of patients under the guise of cutting-edge therapy, creating a robust market of direct-to-consumer (DTC) cell-based services and interventions that at best waste time and money and at worst cause serious harm or death (Bauer et al., 2018).

The following guiding questions were used to frame and develop this case study.

Additional guiding questions to consider include the following:

HSPC transplant was initially only attempted in terminally ill patients (Thomas, 1999). The first recorded bone marrow transfusion was given to a 19-year-old woman with aplastic anemia in 1939 (Osgood et al., 1939). This was long before the Nuremburg Code, the Declaration of Helsinki, or the Belmont Report and anything like current understandings of informed consent (NCPHSBBR, 1979; Rickham, 1964; International Military Tribunal, 1949). There was also little understanding of the factors associated with graft failureno attempts at bone marrow transfusions succeeded, and all patients died. Despite this early experience, the consequences of World War II, particularly the need to improve radiation and burn injury treatment, propelled this work forward (de la Morena and Gatti, 2010).

As human transplant work continued, experiments in mice and dogs in the 1950s and 1960s showed that after lethal radiation, these animals would recover if given autologous bone marrow. However, if given allogeneic marrow, the animal would reject the graft and die or accept the graft but then die from wasting syndrome, which later came to be understood as GVHD (Mannick et al., 1960; Billingham and Brent, 1959; Barnes et al., 1956; Rekers et al., 1950). It became clear that close immunologic matching between donor and recipient and management of GVHD in the recipient would be vital to the success of allogeneic bone marrow transplants (de la Morena and Gatti, 2010).

A 1970 accounting of the reported experience with HSPC transplants to date described approximately 200 allogeneic stem cell graft attempts (six involving fetal tissue) in subjects aged less than 1 to over 80 years, most of which had taken place between 1959 and 1962 (Bortin, 1970). (Of note, there were likely scores of unreported cases; in fact, the author ended the article with a call for reporting of all HSPC transplant attempts to the newly established American College of Surgeons-National Institutes of Health Organ Transplant Registry.) Of the reported cases (which often included the subjects initials), only 11 individuals were unequivocal allogeneic chimeras, and of those, only five were still alive at the time their case was reported. Many of the reported subjects died of opportunistic infections or GVHD, the noting of which often did not capture the true human toll of these deaths. For many years, even success (i.e., engraftment of the transplanted marrow) ended in death due to these other causes (Math et al., 1965; Thomas et al., 1959). As Donnall Thomas, a pioneer and leader in the field who won the Nobel Prize for discoveries concerning organ and cell transplantation in the treatment of human disease in 1990, reflected years later, the experience with allogeneic transplants had been so dismal that questions were raised about whether or not such studies should be continued (Thomas, 2005; Nobel Prize, 1990). In fact, the dismal experience with HSPC transplant eventually led most investigators to discontinue this work in humans, the focus returning for a time to animal studies (Little and Storb, 2002).

However, the discovery of human leukocyte antigen (HLA) in 1958 by Jean Dausset, which helps the immune system differentiate between what is self and what is foreign, and subsequent advances in the understanding of HLA matching and immunosuppression during the 1960s and 1970s led to a resumption of human clinical trials (Nobel Prize, 1980). In 1971, the first successful use of HSPC transplant to treat leukemia was reported (Granot and Storb, 2020). The following decades saw additional developments in HSPC transplant, improving the safety of the intervention, thus enabling its consideration for treatment of a broader array of blood diseases, including the hemoglobinopathies (Granot and Storb, 2020; Apperley, 1993).

The first use of HSPC transplant to cure thalassemia was in 1981, in a 16-month-old child, with an HLA-identical sibling donorthis patient was alive and thalassemia-free more than 20 years later (Bhatia and Walters, 2008; Thomas et al., 1982). Thalassemia major (the most serious form of the disease) requires chronic blood transfusion and chelation for life, a process which leads to gradual iron buildup and related organ damage, including heart failure, which is a common cause of death. Life expectancy for treated patients has increased substantially and varies by thalassemia type and treatment compliance, but patients can now live into their 40s and beyond (Pinto et al., 2019).

The first cure of SCD via HSPC transplant was incidental. An 8-year-old girl with acute myeloid leukemia (AML) was successfully treated for her leukemia with a bone marrow transplant, curing her SCD in the process (Johnson et al., 1984). By this time, life expectancy for an individual with SCD had improved substantially, reaching the mid-20s due to advances in understanding and treatment of the disease (particularly the use of antibiotics to manage the frequent infections that plagued those with the disease) (Wailoo, 2017; Prabhakar et al., 2010). The first five patients, all children, in whom HSPC transplants were used intentionally to treat SCD were reported in 1988 (Vermylen et al., 1988). As Vermylen and colleagues reported, In all cases there was complete cessation of vaso-occlusive episodes and haemolysis (Vermylen et al., 1988).

Around this same time, there were also advancements in the sources of transplantable hematopoietic cells, expanding beyond bone marrow to include peripheral blood stem cells and umbilical cord blood (Gluckman et al., 1989; Kessinger et al., 1988). Cord blood was particularly appealing for a number of reasons, including that it is less immunogenic than the other cell sources, reducing the risk of GVHD.

The development of cord blood transplant has a very different origin story to that of bone marrow, beginning with a hypothesis and the founding of a company (Ballen et al., 2013). The company, Biocyte Corporation (later PharmaStem Therapeutics), funded the early work and held two short-lived patents over the isolation, preservation, and culture of umbilical cord blood (Shyntum and Kalkreuter, 2009). The longevity of the science has thankfully surpassed that of the company that launched it. The first cord bloodbased HSPC transplant was conducted with the approval of the relevant institutional review boards (IRBs) and the French National Ethics Committee, to treat a 5-year-old boy with Fanconi anemia using cells from the birth of an unaffected, HLA-matched sister (Ballen et al., 2013; Gluckman et al., 1989). The success of the early cases (the 5-year-old boy was still alive and well 25 years later) led to the use of unrelated cord blood transplant and expansion of use beyond malignant disease (Ballen et al., 2013; Kurtzberg et al., 1996). Benefits of cord blood include noninvasive collection, ability to cryopreserve characterized tissue for ready use, reduced likelihood of transmitting infections, and lower immunogenicity relative to bone marrow, enabling imperfect HLA matching and expanding access, in particular for people not of European descent (Barker et al., 2010; Gluckman et al., 1997). Cord blood HSPC transplant was first used primarily in children, because it was thought that the relatively low number of cells in a cord blood unit would limit its use in adults, but over time, as techniques and supportive care have improved, so has success of cord blood transplant in adults (Eapen et al., 2010; Ballen et al., 2007). Today, cord blood is widely used for HSPC transplants in both children and adults, with outcomes as good as or better than with bone marrow. Despite these advancements, however, allogeneic HSPC transplant continued to depend on the availability of HLA-matched donors.

Unfortunately, only about 35 percent of patients have HLA-matched siblings, so patients have needed to look beyond their immediate family for matched donors. This need led to the creation of HLA-typed donor registries, starting with the founding of the Europdonor registry in the Netherlands in 1970 and the International Blood and Marrow Transplant Registry at the Medical College of Wisconsin in 1972 (McCann and Gale, 2018). In 1986, the National Marrow Donor Program (NMDP), which operates the Be the Match registry, was founded by the U.S. Navy. Other registries in the United States and Europe followed, and by 1988, there were eight active registries around the world with more than 150,000 donors (van Rood and Oudshoorn, 2008). The Bone Marrow Donors Worldwide network, which connected these registries, was formed in 1988 to facilitate the identification of potential donors, and in 2017 its activities were taken over by the World Marrow Donor Association (WMDA) (Oudshoorn et al., 1994). Today, the combined registry includes more than 37,600,000 donors and more than 800,000 cord blood units from 54 different countries (seeFigure 1) (WMDA, 2021; Petersdorf, 2010).

However, even with tremendous global collaboration to identify and make available donor information, access is not equal. The NMDP estimates suggest that while approximately 90 percent of people of European descent will identify a well-matched unrelated marrow donor, the same will be true for only about 70 percent of people of Asian or Hispanic descent and 60 percent of those of African descent (Pidala et al., 2013). Causes for this disparity include higher HLA diversity among these populations compared to those of European descent and smaller numbers of racial and ethnic minority volunteers in donor registries and ultimately available for transplant (Sacchi et al., 2008; Kollman et al., 2004).

Alongside the public registries, trading on the success of cord blood HSPC transplants and playing on the fears of new parents, a thriving market of private cord blood banks has developed (Murdoch et al., 2020). These for-profit private banks market their servicescollecting and storing cord blood for potential future personal useas insurance policies for the health of ones newborn, without much data to support the claim. While donation of cord blood to a public bank is free to the donor, costs associated with private banking include a collection fee (US$1,350$2,300) and annual storage fees ($100$175/year), which are unlikely to be covered by health insurance (Shearer et al., 2017). At the same time, public banks are held to transparent, rigorous storage and quality standards that do not apply to private banks, leading to lower overall quality of cord blood in private banks (Shearer et al., 2017; Sun et al., 2010; Committee on Obstetric Practice, 2008). Finally, cord blood stored in public banks is 30 times more likely to be accessed for clinical use than samples stored in private banks, and there is broad professional consensus, and associated professional guidance, that public banking is preferable to private banking (Shearer et al., 2017; Ballen et al., 2015). Despite these differences, in 2017, there were about 800,000 cord blood units in public banks, compared with more than 5 million in private banks (Kurtzberg, 2017).

While adult stem cell sources (bone marrow, peripheral blood, and cord blood) have dominated research and clinical care for many decades, in the late 1990s and mid-2000s, new tools were added in the form of several pluripotent stem cell types, including embryonic stem cells, embryonic germ cells, nuclear transfer (NT)-derived stem cells, and most recently, induced pluripotent stem cells (iPSCs) (Tachibana et al., 2013; Yu et al., 2007; Takahashi and Yamanaka, 2006; Shamblott et al., 1998; Thomson et al., 1998). In contrast to the previous cell sources, which are restricted to repopulating blood cell types, these new pluripotent stem cells can turn into any of the approximately 220 cell types in the human body and have a correspondingly diverse array of potential applications. For the purposes of this case, the authors focus on the use of these cells in hematologic disease, but understanding some of the history of the development and use of these cells is helpful for the broader goals of the case. Importantly, these new cell types emerged in a very different regulatory and societal environment than the environment in which bone marrow transplants were first being developed.

The first derivations of human embryonic stem cells (ESCs) and embryonic germ cells (EGCs) were published in 1998 (Shamblott et al., 1998; Thomson et al., 1998). Both of these seminal papers concluded with discussion of the potential for the use of these cells in transplantation-based treatments and cures and emphasized the need to address the challenge of immune rejection, either through the development of cell banks, akin to the registries described previously, or through the genetic modification of the cells to create universal donor cells or to match the particular cellular therapy to the particular patient.

Unlike bone marrow or cord blood, however, the source of these cells was human embryos and fetal tissue, and at the time of these publications, there was already a notable history of governance of these tissues (Matthews and Yang, 2019; Green, 1995; NIH, 1994). In addition, the Dickey-Wicker Amendment had been in place for 3 years, prohibiting the use of federal funds to create human embryos for research or to conduct research in which human embryos are destroyed, discarded, or knowingly subjected to risk of injury or death (104th Congress, 1995). Within weeks of the papers publication, a legal opinion was issued from the Department of Health and Human Services (HHS) interpreting Dickey-Wicker with regard to the new research (Rabb, 1995). Though federal dollars could not be used to create ESCs or EGCs, it was determined that federal dollars could be used to conduct research with pluripotent stem cells thus derived. This interpretation was supported later that year by a report of the National Bioethics Advisory Commission (NBCA, 1999). This did not, however, settle the issue.

A year later, President George W. Bush was elected following a campaign in which he made clear his opposition to this research (Cimons, 2001). In August 2001, in his first address to the nation, President Bush announced that federal funding would be permitted for research using the approximately 60 ESC lines already in existence at the time of his announcement, but not for research with newly derived lines (CNN, 2001). The president seemed to be attempting to walk a fine line between allowing promising research to move forward and not causing the federal government (and taxpayers) to be complicit in the destruction of human embryos. Ultimately, many of these 60 approved Bush lines proved impossible to access or difficult to work with. Furthermore, the accounting required in institutions and laboratories working with both Bush lines and newer lines was daunting (Murugan, 2009).

As ethical and policy debates raged, states began passing their own legislation governing human ESC research, beginning with California, and creating over time a patchwork of state-level policy that ranged from providing government funding for ESC research, as in California, to classifying the work as a felony, such as in Arizona (CIRM.ca.gov, n.d.; Justia US Law, 2020). In 2005, Congress passed its own bill that would permit federal funding of research with an expanded number of human ESC lines, but the bill was subsequently vetoed by President Bush (109th Congress, 2005). The same year, the National Research Council and the Institute of Medicine published its tremendously influential report titled Guidelines for Human Embryonic Stem Cell Research (IOM and NRC, 2005). These guidelines led to highly effective self-regulation in the field, as the Guidelines were adopted across the United States at institutions conducting human ESC research (Robertson, 2010). The Guidelines recommended the creation of a new institutional oversight committee to review ESC research, similar to IRBs, among other recommendations. The Guidelines remained the primary source of governance for ESC research through the end of the Bush administration.

An additional scientific innovation during this time was the announcement of the creation of iPSCs in 2006 (Nobel Prize, 2012; Takahashi and Yamanaka, 2006). iPSCs are derived from somatic tissue, not embryonic or fetal tissue, through the introduction of a small set of transcription factors that effectively reset the mature cell back to a pluripotent state. This concept had actually been introduced as an alternative to ESCs by President Bushs bioethics commission, though it had been met with skepticism, and Shinya Yamanakas announcement at the 2006 International Society for Stem Cell Research (ISSCR) annual meeting stunned the assembled scientists (Scudellari, 2016; The Presidents Council on Bioethics, 2005). This scientific end-run around the destruction of human embryos led to a flood of new researchers, as scientists now needed only somatic cells, rather than highly regulated embryonic or fetal tissue, to participate in this new wave of regenerative medicine research.

By the end of President Bushs second term, in addition to the National Academies Guidelines, guidelines were also issued from the ISSCR and a number of other academic groups (ISSCR, n.d.; The Hinxton Group, 2006). Internationally, as in the United States, a patchwork of policy responses had emerged, ranging from very restrictive to permissive to supportive, leading both domestically and internationally to a degree of brain drain as some scientists relocated to jurisdictions that permitted this research (Verginer and Riccaboni, 2021; Levine, 2012).

When President Barack Obama took office in 2009, he issued an Executive Order reversing former president Bushs prior actions (White House, 2009). Rather than establishing the final rules himself, he permitted funding of ESC research to the extent permitted by law (a nod to the Dickey-Wicker Amendment) and charged the National Institutes of Health (NIH) with developing guidelines for such funding. The NIH guidelines, which largely followed the Guidelines, were finalized in July 2009 and were promptly tied up in a years-long battle in the courts until the Supreme Court declined to hear the final appeal in 2013, leaving the NIH guidelines intact (NIH, 2013, 2009).

The final piece of the regenerative medicine puzzle is the need to overcome immune rejection of transplanted cells. As noted in the initial HPSC papers, potential ways to overcome immune rejection (in the absence of iPSCs) included both banking of a large number of diverse cell lines and genetic modification of the cells intended for transplant, although at the time the technology to do so did not exist (Faden et al., 2003). Gene therapy of this sort had been contemplated for years, and gene transfer trials had begun in the 1990s using the tools scientists had at the time (IOM, 2014). Governance structures grew up around these trials, including the transition of the Recombinant DNA Advisory Committee (RAC) from reviewing NIH-funded research involving recombinant DNA (rDNA) to reviewing gene transfer protocols (IOM, 2014). Of note, though the RAC served as a model internationally for the governance of rDNA research, its mandate was repeatedly questioned and its work critiqued, even as its role evolved (IOM, 2014). As the pace and volume of gene transfer research picked up, the pace of review slowed. Responding not only to the resulting critiques but also the accumulated experience and data, the RAC relaxed restrictions and expedited reviews where possible, ultimately pivoting again to a focus on novel protocols, and leaving more straightforward protocols to the U.S. Food and Drug Administration (FDA) to approve or deny (IOM, 2014). But the original vision of genetically tailored cellular therapy articulated in the 1998 papers did not become possible until almost 15 years later.

In 2012, the publication of the paper that introduced clustered regularly interspaced short palindromic repeats-CRISPR associated protein 9 (CRISPR-Cas9) launched a new era of genetic modification (Jinek et al., 2012). This new tool dramatically improved upon prior gene editing tools with respect to technical ease, speed, and cost, putting the kind of editing imagined in the 1998 papers within reach.

Today, median health care costs for HSPC (including the procedure and 3 months of follow-up) in the United States are approximately $140,000$290,000, depending on the type of procedure (Broder et al., 2017). While 200-day nonremission mortality has decreased substantially since 2000, it remains high (11%) (McDonald et al., 2020). The risks of transplant remain a significant barrier to access, in particular for those with nonmalignant disease, such as SCD. Beyond this, and as noted previously, there are significant ethnic and racial disparities in access to HSPC transplant, largely due to the relatively lower probability of identifying a well-matched HSPC donor (Barker et al., 2019). A recent study demonstrated that while White patients of European descent have a 75 percent chance of finding a well-matched (8/8 HLA-matched) donor, for White Americans of Middle Eastern or North African descent, the probability is 46 percent (Gragert et al., 2014). For Hispanic, Asian, Pacific Islander, and Native American individuals, the probability of such a match ranges from 27 to 52 percent, and for Black Americans, the probability is 1619 percent (Gragert et al., 2014). Contributing to these disparities for racial and ethnic minority groups are higher HLA diversity, smaller numbers of racial and ethnic minority volunteers in donor registries, and the higher rates at which matched minority volunteers become unavailable for donation (e.g., due to inability to reach the volunteer or medical deferral due to diabetes, asthma, infectious disease, or other identified condition) (Sacchi et al., 2008; Kollman et al., 2004). Giving preference to 8/8 HLA-matched pairs therefore benefits White patients and disadvantages patients of color, but removing this preference might result in higher rates of graft failure. Attempts to balance these competing considerations raise ethical questions about justice and beneficence.

Another ethical question in HSPC transplantation revolves around compensation or incentives for donation. Increasing the number and availability of HSCP donors would improve the probability of identifying an appropriate unrelated match for patients in need of a transplant, but the 1984 National Organ Transplant Act (NOTA) banned the sale of bone marrow and organs, making the provision of financial incentives to donate illegal (98th Congress, 1983). Nonetheless, debates over the ethics of providing incentives to encourage the donation of bone marrow and HSCs persist among bioethicists and health economists. In an effort to reduce disincentives to donate, the federal government offers up to 1 work week of leave for federal employees who donate bone marrow, and most states have followed suit for state employees (Lacetera et al., 2014). Some states also offer tax deductions for nonmedical donation-related costs, and there is some evidence that these types of legislation do lead to modest increases in donation rates (Lacetera et al., 2014).

Although removing disincentives to donation is generally considered ethically acceptable, there is more debate about whether offering financial incentives for donation equates to a morally problematic commodification of the human body. In 2011, the 9th Circuit held in Flynn v. Holder that compensation for the collection of PBSCs does not violate NOTAs ban on compensation (Cohen, 2012). In response, a coalition of cell therapy organizations published a statement arguing that this decision would mean that donors would no longer be motivated by altruism, and that people seeking to sell PBSCs might withhold important health information (Be the Match, 2012). After a regulatory back-and-forth over the status of PBSCs, HHS withdrew a proposed rule that would have effectively reversed Flynn v. Holder, so the current state of the law allows compensation for PBSCs (Todd, 2017).

Although Linus Pauling declared sickle cell disease (SCD) to be the first molecular disease (i.e., the first disease understood at the molecular level) in 1949, and it has long been considered an ideal target for gene therapy given that it is predominantly caused by a single mutation in the HBB gene and its phenotypic consequences are in a circulating cell type, developing a cure has not been as straightforward as hoped (Pauling et al., 1949). Though the presentation of SCD can vary significantly, clinical effects include anemia, painful vaso-occlusive crises, acute chest syndrome, splenic sequestration, stroke, chronic pulmonary and renal dysfunction, growth retardation, and premature death (OMIM, n.d.a.).

Standard treatment for SCD consists primarily of preventative and supportive care, including prophylactic penicillin, opioids for severe chronic pain, hydroxyurea, and transfusion therapy (Yawn et al., 2014). Such care has dramatically increased the life expectancy of those living with SCD (median survival in the United States is in the mid- to late 40s) (Wailoo, 2017; Ballas et al., 2016; Prabhakar et al., 2010). At the same time, this care costs more than $35,000 annually, and many patients have difficulty accessing such high-quality care, particularly adequate pain management (Bergman and Diamond, 2013; Haywood, 2013; Haywood et al., 2009; Kauf et al., 2009; Smith et al., 2006). Until recently, the only evidence-based cure for SCD and beta-thalassemia major was allogeneic hematopoietic cell transplantation (HCT), which comes with significant costs and risks (Bhatia and Walters, 2008).

Despite the fact that SCD is one of the most common genetic diseases worldwide and it was the first genetic disease to be molecularly defined, it has received relatively little research funding over the years, an observation that has been a frequent subject of critique (Farooq et al., 2020; Demirci et al., 2019; Benjamin, 2011; Smith et al., 2006; Scott, 1970). In contrast to better-funded diseases, such as cystic fibrosis and Duchenne muscular dystrophy, which are more common in White individuals of European descent, in the United States, SCD predominantly affects non-Hispanic Black and Hispanic populations, including 1 in 365 Black individuals and 1 in 16,300 Hispanic individuals (OMIM, n.d.b., n.d.c.; CDC, 2022). This disparity in research funding despite disease prevalence is part of the larger story of the impacts of structural racism in the United States and on its medical system (The New York Times, 2019; IOM, 2003; HHS and AHRQ, 2003).

Furthermore, as noted previously, those of African and Hispanic ancestry are less likely to be able to identify a suitable match in the existing registries. Due to this difficulty, the improvements in treatment not focused on an HSPC transplant, and the risks of such a transplant, relatively few patients with SCD are treated with HSPC transplant (Yawn et al., 2014; Benjamin, 2011). Gene therapy delivered in the context of an autologous HSPC transplant offers the possibility not only of a safer cure but also broader access by eliminating the need to identify a matched donor.

Recently, the promise of regenerative medicine and gene therapy for genetic hematologic disease appears to be coming to fruition (Ledford, 2020; Stein, 2020; Kolata, 2019). While a number of approaches are currently in various stages of preclinical and clinical research, two promising clinical trials involve the induction of fetal hemoglobin (rather than direct correction of the disease-causing mutation in the HBB gene) (Demirci et al., 2019). Fetal hemoglobin is the predominant globin type in the second and third trimester fetus and for the first few months of life, at which point production shifts from fetal to adult hemoglobin. It has long been recognized that SCD does not present until after this shift occurs (Watson et al., 1948). Furthermore, some patients with the causative SCD mutation are nonetheless asymptomatic, due to also having inherited hereditary persistence of fetal hemoglobin mutations (Stamatoyannopoulos et al., 1975). These findings and others suggested that inducing fetal hemoglobin, even in the presence of a faulty HBB gene, could mitigate the disease.

The first trial uses a viral vector to introduce into autologous bone marrow a short hairpin RNA (shRNA) that inhibits the action of the BCL11A gene. BCL11A is an inhibitor of fetal hemoglobin, so when BCL11A is inhibited, fetal hemoglobin can be produced (Esrick et al., 2021). The second trialthe first published study to use CRISPR to treat a genetic diseaseincludes both patients with SCD and with transfusion-dependent -thalassemia (Frangoul et al., 2021). In this trial, CRISPR-Cas9 is used to target the BCL11A gene to affect the same de-repression of fetal hemoglobin as in the first trial. Both trials, which have collectively enrolled more than 15 patients, have reduced or eliminated the clinical manifestation of disease in all patients thus far, though it remains to be seen how long-lasting this effect will be. However, the first trial was recently suspended after participants in the first trial and a related trial developed acute myeloid leukemia (AML) or myelodysplastic syndrome (MDS) (Liu, 2021); an investigation is under way regarding the cause of the AML and MDS. Marketing of a treatment for transfusion-dependent -thalassemia currently approved and available in the European Union (EU) was also suspended, as that treatment is manufactured using the same vector (BB305 lentiviral vector) used in the current trials, and it is possible that the vector is the source of the serious adverse events in the research participants.

Further challenges remain, including technical challenges, such as the possibility that gene editing tools, as they are derived from bacterial systems, will provoke an immune response; and concerns about financial access, given the anticipated cost of such curative therapies (ICER, 2021; Kim et al., 2018). In addition, despite the technical ease of the technology and designing new nucleic acid targets, intellectual property protecting CRISPR has, to date, narrowed the number of developers actively pursuing CRISPR-based clinical trials (Sherkow, 2017). At the same time, this new technology might also solve a number of ethical issues around HSPC transplants, including by expanding biological access to HSPC transplant and mitigating the concerns raised by the creation of savior siblings for HLA-matched cord blood transplantation for older siblings (Kahn and Mastroianni, 2004).

A long-standing challenge in the field of regenerative medicine is the DTC marketing of unproven cell-based interventions. Since at least the 2000s, unscrupulous scientists and health professionals in the United States and internationally have been offering stem cell therapy at significant cost, often to vulnerable individuals, and without a legitimate scientific or medical basis (Knoepfler and Turner, 2018; Murdoch et al., 2018; Regenberg et al., 2009; Enserink, 2006). From 2009 to 2016, the number of such clinics in the United States doubled annually (Knoepfler and Turner, 2018). While the clinics look legitimate, their claims are fantastical, promising to treat or cure everything from knee pain to Parkinsons disease. Such clinics are often vague about the cell sources involved in the interventions offered, but sometimes they claim to use bone marrow, cord blood, embryonic stem cells, and iPSCs, as well as other types of autologous adult stem cells (e.g., adipose, olfactory) and a range of other cell types, cell sources, and cell mixtures (Murdoch et al., 2018). While such interventions launch from legitimate science and scientific potential, the claims exceed and diverge from what is proven. The interventions are at best very expensive placebos and at worst could cause serious harm or death (Bauer et al., 2018).

Over time, attempts have been made to rein in these clinics by the FDA, the Federal Trade Commission (FTC), the ISSCR, individual customers and their lawyers, and others, but these attempts have faced a number of challenges (Pearce, 2020). The ISSCR, the primary professional society for those engaged in regenerative medicine, has struggled for years against such clinics. Early on, they attempted to establish a mechanism to publicly vet these clinics, though the effort was abandoned in part due to push back from the clinics lawyers (Taylor et al., 2010; personal communication from ISSCR Leadership, n.d.). In part because the majority of US-based clinics offer autologous interventions (removing and then reintroducing the patients own cells), the FDA struggled to clarify the line between medical practice and their regulatory authority. The FDA began issuing occasional warning letters to these clinics starting in 2011, though the letters were issued infrequently (Knoepfler and Turner, 2018). Under this relatively weak enforcement, the market expanded dramatically, and pressure increased on the FDA to take meaningful action (Knoepfler, 2018; Turner and Knoepfler, 2016).

In late 2017, the FDA took several significant steps to curtail these clinics, including using U.S. marshals to seize product from a California clinic, bringing a lawsuit against a Florida clinic, and publishing largely celebrated finalized guidance outlining a risk-based approach to the regulation of regenerative medicine products (FDA, 2019; Pew Research Center, 2019). The following year, the FTC took independent action against clinics making false claims about their interventions, and Google banned advertising for unproven or experimental medical techniques such as most stem cell therapy, cellular (non-stem) therapy, and gene therapy (Biddings, 2019; Fair, 2018). In 2019, the FDA won their case against US Stem Cells in Florida, significantly strengthening their ability to regulate these clinics (Wan and McGinley, 2019). Following the establishment of clear regulatory authority over at least a subset of clinics, FDA has begun to step up its enforcement (Knoepfler, 2020; Wan and McGinley, 2019; FDA, 2018). Increased action is anticipated following the end of the 3-year grace period established in the 2017 guidance, though there is some concern about the capacity of the agency to make significant headway against the more than 600 clinics now in operationa worry bolstered by a 2019 study suggesting that despite increased enforcement, the unproven stem cell market seems to have shifted rather than contracted (Knoepfler, 2019; Pew Research Center, 2019). What seems clear is that it will take a collective and multipronged approach to ensure that the cell-based interventions to which patients have access are safe and effective (Lomax et al., 2020; Pew Research Center, 2019; Master et al., 2017; Zarzeczny et al., 2014).

The cross-sectoral analysis is structured according to sectors (seeFigure 2) and domains (science and technology, governance and enforcement, end-user affordability and insurance reimbursement [affordability and reimbursement], private companies, and social and ethical considerations). The sectors described subsequently are intended to be sufficiently broad to encompass a number of individuals, groups, and institutions that have an interest or role in regenerative medicine. Health care is the primary nonprofit actor of interest, and so in this structure, health care has replaced nonprofit, though other nonprofit actors may have a role in this and other emerging technologies, and, of course, not all health care institutions are nonprofits.

Today, many regenerative medicine technologies are researched, developed, and promoted by a scientific-industrial complex largely driven by market-oriented goals. The development of various components of regenerative medicine may be altered by differing intellectual property regimes. This larger ecosystem is also embedded in a broad geopolitical context, in which the political and the economic are deeply intertwined, shaping national and regional investment and regulation. The political economy of emerging technologies involves and affects not only global markets and regulatory systems across different levels of government but also nonstate actors and international governance bodies. Individuals and societies subsequently adopt emerging technologies, adjusting their own values, attitudes, and norms as necessary, even as these technologies begin to shape the environments where they are deployed or adopted. Furthermore, individual and collective interests may change as the hype cycle of an emerging technology evolves (Gartner, 2022). Stakeholders in this process may include scientific and technological researchers, business firms and industry associations, government officials, civil society groups, worker safety groups, privacy advocates, and environmental protection groups, as well as economic and social justicefocused stakeholders (Marchant et al., 2014).

This intricate ecosystem of stakeholders and interests may be further complicated by the simultaneous introduction of other technologies and platforms with different constellations of ethical issues, modes of governance, and political economy contexts. In the following sections, this ecosystem is disaggregated and organized for ease of presentation. It is important to keep in mind that there are entanglements and feedback loops between and among the different sectors, such that pulling on a single thread in one sector often affects multiple areas and actors across the broader ecosystem.

For the purposes of this case study, the primary actors within the academic sector are academic and clinical researchers and the professional societies that represent them.

Science and technology:This case involves a tremendous amount of research and development that has taken place in and grown out of academia, including preclinical and clinical HSPC transplant research; human ESC, EGC, and iPSC research; and genome editing.

Governance and enforcement:Current work at research institutions is governed by IRBs and REBs, stem cell research oversight committees, and institutional animal care and use committees, among other bodies. In addition, research funding bodies, academic publication standards, and scientific and professional societies (i.e., self-regulation) also have a role to playin particular, the ISSCR and its role in the governance of pluripotent stem cell research and in addressing clinics offering unproven cell-based therapies. The National Academies of Sciences, Engineering, and Medicine played a critical role in the governance of ESC research, particularly from 2005 until 2010.

Affordability and reimbursement:While not strictly a matter of patient affordability, it is important to reiterate, as noted previously, that funding available for academic research has disproportionately benefited those with diseases such as cystic fibrosis and Duchenne muscular dystrophy, which are more common in White individuals of European descent, compared to SCD, which in the United States is more prevalent among non-Hispanic Black and Hispanic populations (Farooq et al., 2020; Demirci et al., 2019; Benjamin, 2011; Smith et al., 2006; Scott, 1970).

Private companies:Academicindustry research partnerships, including industry-funded clinical trials, are involved in this space; for example, the CRISPR-based clinical trial was funded by two biotechnology companies (Frangoul et al., 2021). Such partnerships are often predicated on exclusive intellectual property licenses to surrogate licensors (Contreras and Sherkow, 2017).

Social and ethical considerations:Extensive bioethics literature exists on the ethical, legal, and societal issues raised by human subjects research, first-in-human clinical trials, stem cell research, clinics offering unproven cell-based interventions, genome editing, health disparities, and structural racism. Much has also been written on the role of intellectual property and data and materials sharing in the context of human tissue research and genome editing.

Given the focus of CESTI on health and medicine, for the purpose of this case study, the primary actors within the nonprofit sector are those involved in health care, including hematopoietic stem and progenitor cell registries, health insurance companies, and medical profession associations.

Science and technology:HSPC transplants have been clinically available for decades, but research and improvement in this space continue.

Governance and enforcement:Today, the WMDA serves as the accrediting body for registries and promulgates regulations and standards to which the registries adhere on issues like the organization of a registry, the recruitment of volunteer donors, and the collection and transportation of HPCs (WMDA, 2022; Hurley et al., 2010). These standards represent the minimum guidelines for registries, which demonstrate their commitment to comply with WMDA Standards through the WMDA accreditation process (Hurley et al., 2010). Other groups involved in the governance of aspects of HSPC transplant are included inTable 1.

It is important to note that the nonprofit label in this context is somewhat fraught. Many (perhaps most) health care organizations are very much in the business of making money. One of these is the NMDP, which operates Be the Match, and which has diversified its portfolio over time, including the launch in 2016 of Be the Match BioTherapies, which partners with dozens of cell and gene therapy companies, supplying cells and services to advance the development of life-saving cell and gene therapies (Be the Match, 2021a,b).

The FDA generally has authority to regulate bone marrow transplantation through its oversight of bone marrow itself as a human cellular tissue product (HCT/P) and, therefore, a biologic (U.S. Code 262, n.d.). Typically, biologic products are required to submit to the FDAs premarket review process, including the filing of an investigative new drug application and clinical trials. With that said, the FDA has exempted certain types of bone marrow transplantation procedures from such review: namely, bone marrow products that are used in a same-day surgical procedure and those that are only minimally manipulated (FDA, 2020). Importantly, while the FDAs minimally manipulated exception broadly applies to autologous therapy, including the sort of therapy private cord blood banks are intended to plan for, it only applies to allogenic therapy if derived from a first-degree or second-degree blood relative; allogenic therapy using cells from more distant relatives requires the FDAs premarket review (FDA, 2020).

Cord blood matching and donor priority is controlled by the NMDP and regulated by the FDA (CFR, 2012). However, because cord blood therapy is almost always allogenic and usually from anonymized donors unrelated to the patient, cord blood HSPC transplant generally does not fulfill the FDAs minimal manipulation exemptions for HCT/P (FDA, 2020). As such, a total of eight public cord blood banks have applied for, and received, approval from the FDA for their cord blood products (FDA, 2022). Generally, public banks are held to transparent, rigorous storage and quality standards that do not apply to private banks, leading to lower overall quality of cord blood in private banks (Shearer et al., 2017; Sun et al., 2010; Committee on Obstetric Practice, 2008).

The American Academy of Pediatrics has taken a position on private versus public cord blood banks and supports public banking, as do the American Medical Association and the American Congress of Obstetricians and Gynecologists (AMA, n.d.; ACOG, 2019; Shearer et al., 2017).

Affordability and reimbursement:Both public and private insurers in the United States tend to distinguish autologous from allogenic bone marrow therapies, covering autologous transplantation for some indications and allogenic transplantation for others (CMS, 2016).

Leaving aside the broader issues of health insurance and health care affordability in the United States, annual and lifelong care costs for genetic hematologic diseases like SCD and thalassemia are considerablethe yearly cost of standard of care for a patient with SCD is more than $35,000 (Kauf et al., 2009). Novel therapiesboth pharmacologic and those based on HSPC transplantsare anticipated to be extraordinarily expensive, if proven safe and effective. For example, the drugs Oxbryta and Adakveo, approved in 2019 for treating SCD, are estimated to cost $84,000 and $88,000 per year, respectively (ICER, 2021; Sagonowsky, 2020). CART-T cell therapy, which as another novel, genetically modified cell-based therapy may be a reasonable bellwether for the cost of the SCD therapies described previously, costs at least $373,000 for a single infusion before hospital and other associated costs (Beasley, 2019). Many patients suffering from these diseases are from historically marginalized and underserved populations that tend to have lower levels of income. In addition, as therapies become more bespoke, scaling will increasingly become a challenge, from both a regulatory and delivery perspective. However, these delivery challenges may also open new business opportunities.

While donation of cord blood to a public bank is free to the donor, costs associated with private banking include a collection fee ($1,350$2,300) and annual storage fees ($100$175 a year), which are unlikely to be covered by health insurance (Shearer et al., 2017).

Private companies:Many private companies advertise private cord blood banking to new parents as a form of biological insurance; however, the costs of collection and storage are not generally covered by medical insurance (private companies offering unproven cell-based interventions are included under the private sector rather than health care).

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