Meeting the growing needs of the perinatal RegenMed Industry: the only Umbilical Cord hMSC (hUC-MSC) system designed for today’s translationally focused research and product development

Authored by Iain Farrance, PhD, Technical Marketing Associate

Introduction

Human mesenchymal stromal cells (hMSC) are considered the "workhorse" of Regenerative Medicine (RegenMed).  hMSC are a critical starting material in a growing variety of established and emerging RegenMed products, including cellular therapies, cell-based gene therapies, hMSC-derived extracellular vesicles (EVs), and bioprinted engineered tissues (Olsen, 2018). Accordingly, there have been greater than 100 clinical trials initiated each year since 2011 using hMSC from various sources (database purchased from celltrials.org) across a host of indications and therapeutic strategies (clinical trials.gov).  hMSC have benefitted from having an excellent safety profile, and there have been nine (9) products approved globally over the last 10 years. The growth in use of hMSC in a variety of product types has created the opportunity to standardize the supply chain and provide economies of scale for a rapidly growing industry. RoosterBio was founded to industrialize and standardize the RegenMed supply chain and to radically simplify the incorporation of living cells into therapeutic product development. Our goal is to have the same impact on the RegenMed industry that Intel had on the computer industry.

Use of Human Umbilical Cord-derived MSCs (hUC-MSC) in research and clinical trials (CT) has grown rapidly over the last 10 to 15 years with quickest adoption in APAC (Figure 1, Davies, 2017; Zhao, 2018; Moll, 2019). hUC-MSC publications per year increased 19-fold increase from 2006 to 2016 (Zhao, 2018). CT with hUC-MSC have shown a similar growth pattern as publications. hUC-MSC are the second most used hMSC type in CT (Moll, 2019) and 178 CT using hUC-MSC were registered, are ongoing, or were completed between 2007 and 2017 (Couto, 2019). In fact, >30% of hMSC trials registered in 2019 use hUC-MSC as the cell source.  These drive the need for hUC-MSC to use in product development. Until now, IP surrounding hUC-MSC has been a primary roadblock to the widespread adoption of hUC-MSC. We have collaborated with leaders in Wharton’s Jelly/umbilical cord hMSC at Tissue RegenerationTherapeutics Inc. (TRT) and have brought to market a complete bioprocess cell and media system. RoosterBio’s hUC-MSC are available for licensing and are provided in scalable formulations and cGMP compatible processes that enable anyone to obtain hUC-MSC in numbers needed for incorporation into RegenMed product development.

Until now RoosterBio has paired our batch (2D) and fed-batch (3D bioreactor) bioprocess media systems with hMSC from two sources: adipose-derived (hAD-MSC) and bone marrow-derived (hBM-MSC and xeno-free (XF) hBM-MSC). RoosterBio’s launch of our XF hUC-MSC (RoosterVial™-hUC-MSC-XF) introduces the first umbilical cord-derived hMSC in the North American and worldwide market designed to meet the quality and volume needs of today’s translationally focused cell therapy product developers. For RoosterBio’s hMSC product lines see here.

RoosterBio’s RoosterVial-hUC-MSC-XF and RoosterNourish™-MSC cell and medium bioprocess system has several key advantages over the limited number of suppliers of perinatal hMSC. Being XF, and manufactured with RoosterBio’s existing cGMP compatible processes, our system is the only hUC-MSC commercially available with a clear line of sight to clinical translation.  Additionally, other suppliers (a) provide low cell number vials at a high price per M cells, (b) supply serum-based cells, or (c) require specialized, non-scalable culture vessels.  Finally, RoosterBio provides first in class characterization of hMSC key quality attributes (PDL, identity, expansion potential) and functional assays (cytokine secretion, trilineage differentiation, immunomodulation).

Good Manufacturing Practice for Cell and Cell-Based Therapies: Facilities & Quality Control

Novel cell and cell-based therapies require stringent manufacturing, testing and oversight to ensure integrity, function, and above all else, patient safety upon administration.  Tissue-derived cellular products are considered to be manufactured products and are regulated as such.  Thus, you must ensure that your cell manufacturing process is aligned to current Good Manufacturing Practice requirements.  (Note the “current”.  This means that these are evolving requirements, so you must stay up-to-date!)  In the United States, human cells, tissue and cellular- and tissue-based products (HCT/Ps) are regulated by the Center for Biologics Evaluation and Research (CBER), a division of the U.S. Food and Drug Administration (FDA).

When manufacturing cell and cell-based products, a production facility under strict Quality Control must be used.  Ideally, this facility includes the cell manufacturing suites, the storage space for raw and finished product and any laboratory/testing areas.  Thus, (1) facility design, access and maintenance, (2) equipment purchase, installation and operational qualification (I/OQ), use and maintenance and (3) raw material specifications, purchase, use and storage must all be carefully controlled.  For cell and cell-based therapies, terminal sterilization of the final product is often not possible.  As such, quality by design (QbD) is highly important in cell therapy, with stringent testing conducted on the tissue Donor (our next blog post in this series will cover this topic) to preclude risk of contamination at the source.  In addition, facility and equipment standards and monitoring must be instituted to ensure aseptic processing of cell and cell-based products.  To this end, closed systems and single-use disposables should be used whenever possible to minimize risk of contamination.  Therefore, a cGMP manufacturing facility must include clean rooms which control for temperature, humidity, pressure and air particulates, preventing any contamination of manufactured product due to the environment, materials, human handlers and cross-contamination from other products manufactured in the same facility.  As such, there should be uni-directional flow of materials and people through these areas and personnel must follow proper gowning procedures.  Facilities and equipment requirements are defined under US FDA 21CFR§211 and 21CFR§1271.

As mentioned above, stringent Quality Control systems must be in place to qualify all reagents and processes and to institute Standard Operating Procedures (SOPs) to ensure quality and consistency in manufacturing processes and the end product. 

Facility and Quality Control considerations for cGMP cell manufacturing.

Demystifying Clinical Translation of Stem Cell-Based Therapies

As our company matures and we continue to execute to our mission of accelerating Regenerative Medicine, we find ourselves increasingly involved in conversations around scalable cGMP cell manufacturing, qualification of cell and cell-based therapies, and regulations around clinical translation of hMSCs and hMSC-based therapeutics.  While the US FDA and other global regulatory agencies provide guidances on the regulations surrounding clinical translation of cellular products, it is evident that there is still great uncertainty around rules, regulations, processes, timelines and costs associated with clinical translation.

How do you move from pre-clinical to clinical studies?

How must you manufacture your cells?

What data do you need to present to the FDA to move to clinical trials?

What sort of characterization assays are needed? 

What is the process for engaging the FDA and moving to clinical trials?

When do I need to do all of this?!

These are just a few of the questions that we commonly hear from our customers.  In an effort to facilitate our customers’ path to the clinic, we will be publishing here a series of blog posts on clinical translation of hMSCs.  These posts are meant to point you to the relevant guidances and points to consider surrounding clinical translation of hMSCs and are not meant to be the definitive authority on these matters.  We recommend that you engage your Quality and Regulatory teams (and/or consultants) early on in your Process Development efforts to ensure that you are considering all regulations and guidelines in developing a scalable, clinically- and commercially-relevant process and product.

What other questions do you have around clinical translation of hMSCs and hMSC-based therapies?

Check back in next week for our first blog post in this series.

Guest Blog Post: The Ambitious Future of Tissue Engineering

Bagrat Grigoryan and Jordan Miller, Physiologic Systems Engineering & Advanced Materials Lab at Rice University.

Over the last several decades, various advances in tissue engineering have allowed for the not so distant possibility of replacing, repairing, or regenerating injured tissues¹. Significant progress has been made in understanding cellular biology as well as pathophysiology and healthy states of tissues. Additionally, a suite of diverse biofabrication technologies and biomaterials has been conceived, enabling fabrication of complex 3D tissues with greater physiological relevance compared to the traditional 2D context that cells are studied in². However, the field of tissue engineering still has unresolved questions involving choice of fabrication technique, biomaterial, cellular niche, or even cell type when designing a synthetic tissue.

While different fabrication techniques and biomaterials have been explored in fabricating tissues in vitro, the use of stem cells in engineered tissues is ubiquitous. Not surprisingly so, as biologists continually demonstrate novel ways of directing different lineage commitment of stem cells and further unlocking their vast regenerative potential³. Indeed, stem cell banks have emerged to cryogenically store a patient’s own cells as the therapeutic potential of stem cells is being positively demonstrated in multiple clinical trials⁴. With over 450 mesenchymal stem cell (MSC)-based trials alone currently ongoing or completed, the regenerative and immunoregulatory properties of MSCs are constantly being exploited to improve the quality of human life⁵.

Due to the immense therapeutic potential of MSCs, there is a need to rapidly and reproducibly grow a vast amount of MSCs for clinical and research purposes. Although MSCs were identified and isolated from bone marrow more than 40 years ago, we still have not fully mapped their biological characteristics³.

The Use of Animal Serum in the Clinical Translation of hMSCs

Human mesenchymal stem or stromal cells (hMSCs) are an integral part of cell-based therapeutics, with over 400 clinical trials recently completed or in progress using hMSCs. As more research teams transition their stem cell-based regenerative technologies to the clinic, the use of serum in the cell production process has been, and will continue to be, a necessary evil that must be managed.  Luckily, pharmaceutical regulatory agencies, driven by the biologics industry over the last 30 years, have established guidances and guidelines that have helped to demystify and clarify some critical aspects of dealing with animal components. As it is important to have an understanding of how to manage serum during the clinical translation of hMSCs, we have focused this blog post on this specific topic

There are many researchers in the MSC community who firmly believe that the FDA simply does not allow hMSCs into clinical trials if the cells have been cultured in media supplemented with animal serum. This is currently not the case, and in fact, Mendicino et al. from the Center for Biologics Evaluation and Research at the FDA reviewed all MSC regulatory filings and found that over 80% of all regulatory submissions described the use of fetal bovine serum (FBS) during the hMSC manufacturing process [1]. Several other analyses of hMSC-based clinical trials in recent years have similarly shown that at least 65-75% of trials utilize FBS [2,3,4]. Regardless, a push to remove serum from the manufacturing process still continues due to regulatory, production and supply chain concerns.  Each of these areas is detailed below.

(Note: when we refer to "clinical-grade" products below, this is not an official regulatory classification, it is meant to generally refer to materials that are destined for use in clinical testing of cell therapies.)

Regulatory Compliance      

The main regulatory concerns associated with the use of xenogeneic serum include the risk of contamination with non-human pathogens and inducing an unwanted immune response. To account for such serious consequences, the FDA has put several requirements in place for the production process of both clinical-grade FBS and hMSCs:

• FBS: Clinical-grade FBS must be derived from cattle herds grown in countries that are USDA approved for import, with well-monitored animal health status [2]. The FBS should be processed under current good manufacturing practice (cGMP) standards that set minimum requirements for the facilities, materials and protocols used [2]. Every batch or lot of FBS must be traceable back to its country, slaughterhouse and herd of origin. Finally, all lots must be tested for adventitious agents (viral contamination), sterility (bacterial and fungal elements), endotoxin levels, mycoplasma content and other constituents [2,5]. While regulatory agencies address safety, it is up to the cell manufacturer to establish metrics around performance, as FBS has traditionally been both a major cost driver and a source of process variablity.
• Clinical-grade hMSCs: Clinical-grade hMSCs must be manufactured under cGMP standards, and this topic is covered extensively in the literature.  As it pertains to serum use, each lot of serum used during the cell production process must be documented [5], and the final cell product must meet specific standards of identity, potency, purity and safety. Purity standards include freedom from unwanted contaminants (such as other cell types, endotoxins, residual proteins and animal serum) [6]. The FDA Code of Regulations for Biologics provides a guideline for vaccines that animal serum levels must be under 1 ppm in the final product formulation when serum is used in any part of the process [US FDA. 21 CFR 610.15 ].  While there is no direct guidance for cellular therapies, the 1ppm residual level has been used as a target in some cell therapy manufacturing processes [6] and is a good place to start when developing process specifications.

These checks and balances have allowed clinical trials using FBS-cultured hMSCs to be conducted safely. A meta-analysis by Lalu et al. showed that there was no evidence of infection or toxicity in any subjects involved in clinical trials using FBS-cultured hMSCs [7]. Several other clinical trials have described the use of FBS in cellular therapeutics and biologics without any adverse side effects [8-12]. That said, it is best practice to develop sufficient cell washing protocols after cell harvest, and before formulation, to remove process impurities and get serum protein levels down to acceptable levels [13].

For FDA resources on this topic, see: