The management of risk and investment in cell therapy process development: a case study for neurodegenerative disease

Cell-based therapies must achieve clinical efficacy and safety with reproducible and cost-effective manufacturing. This study addresses process development issues using the exemplar of a human pluripotent stem cell-based dopaminergic neuron cell therapy product. Early identification and correction of risks to product safety and the manufacturing process reduces the expensive and time-consuming bridging studies later in development. A New Product Introduction map was used to determine the developmental requirements specific to the product. Systematic Risk Analysis is exemplified here. Expected current value-based prioritization guides decisions about the sequence of process studies and whether and if an early abandonment of further research is appropriate. The application of the three tools enabled prioritization of the development studies.

Comparability: manufacturing, characterization and controls, report of a UK Regenerative Medicine Platform Pluripotent Stem Cell Platform Workshop, Trinity Hall, Cambridge, 14-15 September 2015

This paper summarizes the proceedings of a workshop held at Trinity Hall, Cambridge to discuss comparability and includes additional information and references to related information added subsequently to the workshop. Comparability is the need to demonstrate equivalence of product after a process change; a recent publication states that this ‘may be difficult for cell-based medicinal products’. Therefore a well-managed change process is required which needs access to good science and regulatory advice and developers are encouraged to seek help early. The workshop shared current thinking and best practice and allowed the definition of key research questions. The intent of this report is to summarize the key issues and the consensus reached on each of these by the expert delegates.

A 3D bioprinting exemplar of the consequences of the regulatory requirements on customized processes

Computer-aided 3D printing approaches to the industrial production of customized 3D functional living constructs for restoration of tissue and organ function face significant regulatory challenges. Using the manufacture of a customized, 3D-bioprinted nasal implant as a well-informed but hypothetical exemplar, we examine how these products might be regulated. Existing EU and USA regulatory frameworks do not account for the differences between 3D printing and conventional manufacturing methods or the ability to create individual customized products using mechanized rather than craft approaches. Already subject to extensive regulatory control, issues related to control of the computer-aided design to manufacture process and the associated software system chain present additional scientific and regulatory challenges for manufacturers of these complex 3D-bioprinted advanced combination products.

Qualification of academic facilities for small-scale automated manufacture of autologous cell-based products

Academic centers, hospitals and small companies, as typical development settings for UK regenerative medicine assets, are significant contributors to the development of autologous cell-based therapies. Often lacking the appropriate funding, quality assurance heritage or specialist regulatory expertise, qualifying aseptic cell processing facilities for GMP compliance is a significant challenge. The qualification of a new Cell Therapy Manufacturing Facility with automated processing capability, the first of its kind in a UK academic setting, provides a unique demonstrator for the qualification of small-scale, automated facilities for GMP-compliant manufacture of autologous cell-based products in these settings. This paper shares our experiences in qualifying the Cell Therapy Manufacturing Facility, focusing on our approach to streamlining the qualification effort, the challenges, project delays and inefficiencies we encountered, and the subsequent lessons learned.

Improving umbilical cord blood processing to increase total nucleated cell count yield and reduce cord input wastage by managing the consequences of input variation

BACKGROUND AIMS

With the rising use of umbilical cord blood (UCB) as an alternative source of hematopoietic stem cells, storage inventories of UCB have grown, giving rise to genetically diverse inventories globally. In the absence of reliable markers such as CD34 or counts of colony-forming units, total nucleated cell (TNC) counts are often used as an indicator of potency, and transplant centers worldwide often select units with the largest counts of TNC. As a result, cord blood banks are driven to increase the quality of stored inventories by increasing the TNC count of products stored. However, these banks face challenges in recovering consistent levels of TNC with the use of the standard protocols of automated umbilical cord processing systems, particularly in the presence of input variation both of cord blood volume and TNC count, in which it is currently not possible to process larger but useable UCB units with consequent losses in TNC.

METHODS

This report addresses the challenge of recovering consistently high TNC yields in volume reduction by proposing and validating an alternative protocol capable of processing a larger range of units more reliably.

RESULTS

This work demonstrates improvements in plastic ware and tubing sets and in the recovery process protocol with consequent productivity gains in TNC yield and a reduction in standard deviation.

CONCLUSIONS

This work could pave the way for cord blood banks to improve UCB processing and increase efficiency through higher yields and lower costs.

Manufacturing models permitting roll out/scale out of clinically led autologous cell therapies: regulatory and scientific challenges for comparability

Manufacturing of more-than-minimally manipulated autologous cell therapies presents a number of unique challenges driven by complex supply logistics and the need to scale out production to multiple manufacturing sites or near the patient within hospital settings. The existing regulatory structure in Europe and the United States imposes a requirement to establish and maintain comparability between sites. Under a single market authorization, this is likely to become an unsurmountable burden beyond two or three sites. Unless alternative manufacturing approaches can be found to bridge the regulatory challenge of comparability, realizing a sustainable and investable business model for affordable autologous cell therapy supply is likely to be extremely demanding. Without a proactive approach by the regulators to close this "translational gap," these products may not progress down the development pipeline, threatening patient accessibility to an increasing number of clinician-led autologous cellular therapies that are already demonstrating patient benefits. We propose three prospective manufacturing models for the scale out/roll out of more-than-minimally manipulated clinically led autologous cell therapy products and test their prospects for addressing the challenge of product comparability with a selected expert reference panel of US and UK thought leaders. This paper presents the perspectives and insights of the panel and identifies where operational, technological and scientific improvements should be prioritized. The main purpose of this report is to solicit feedback and seek input from key stakeholders active in the field of autologous cell therapy in establishing a consensus-based manufacturing approach that may permit the roll out of clinically led autologous cell therapies.

Application of response surface methodology to maximize the productivity of scalable automated human embryonic stem cell manufacture

Aim: Commercial regenerative medicine will require large quantities of clinical-specification human cells. The cost and quality of manufacture is notoriously difficult to control due to highly complex processes with poorly defined tolerances. As a step to overcome this, we aimed to demonstrate the use of ‘quality-by-design’ tools to define the operating space for economic passage of a scalable human embryonic stem cell production method with minimal cell loss. Materials & methods: Design of experiments response surface methodology was applied to generate empirical models to predict optimal operating conditions for a unit of manufacture of a previously developed automatable and scalable human embryonic stem cell production method. Results & conclusion: Two models were defined to predict cell yield and cell recovery rate postpassage, in terms of the predictor variables of media volume, cell seeding density, media exchange and length of passage. Predicted operating conditions for maximized productivity were successfully validated. Such ‘quality-by-design’ type approaches to process design and optimization will be essential to reduce the risk of product failure and patient harm, and to build regulatory confidence in cell therapy manufacturing processes.

Regenerative medicine, resource and regulation: lessons learned from the remedi project

The successful commercialization of regenerative medicine products provides a unique challenge to the manufacturer owing to a lack of suitable investment/business models and a constantly evolving regulatory framework. The resultant slow translation of scientific discovery into safe and clinically efficacious therapies is preventing many potential products from reaching the market. This is despite of the need for new therapies that may reduce the burden on the world's healthcare systems and address the desperate need for replacement tissues and organs. The collaborative Engineering and Physical Sciences Research Council (EPSRC)-funded remedi project was devised to take a holistic but manufacturing-led approach to the challenge of translational regenerative medicine in the UK. Through strategic collaborations and discussions with industry and other academic partners, many of the positive and negative issues surrounding business and regulatory success have been documented to provide a remedi-led perspective on the management of risk in business and the elucidation of the regulatory pathways, and how the two are inherently linked. This article represents the findings from these discussions with key stakeholders and the research into best business and regulatory practices.

Achieving reimbursement for regenerative medicine products in the USA

Achieving reimbursement for regenerative medicine products is potentially a greater challenge than gaining US FDA approval, making it a decisive factor in the success or failure of small businesses. However, the mechanisms by which reimbursement is achieved are still seen as something of a ‘black box’, especially to those outside of the USA. This report aims to provide insights into the mechanisms of reimbursement and variety of payers in the USA, and to act as a starting point for a successful US reimbursement strategy. Fundamental concepts such as coverage, payment and coding are explained and linked with the factors that potentially determine the successful reimbursement of regenerative medicine products, including cost of goods and clinical study design. Finally, important considerations for the design of clinical studies that satisfy both the payers and the FDA are discussed and the key elements of a successful company strategy identified.

Human cell culture process capability: a comparison of manual and automated production

Cell culture is one of the critical bioprocessing steps required to generate sufficient human-derived cellular material for most cell-based therapeutic applications in regenerative medicine. Automated cell expansion is fundamental to the development of scaled, robust and cost effective commercial production processes for cell-based therapeutic products. This paper describes the first application of process capability analysis to establish and compare the short-term process capability of manual and automated processes for the in vitro expansion of a selected anchorage-dependent cell line. Estimates of the process capability indices (Cp, Cpk) have been used to assess the ability of both processes to consistently meet the requirements for a selected productivity output and to direct process improvement activities. Point estimates of Cp and Cpk show that the manual process has poor capability (Cp = 0.55, Cpk = 0.26) compared to the automated process (Cp = 1.32, Cpk = 0.25), resulting from excess variability. Comparison of point estimates, which shows that Cpk < Cp, indicates that the automated process mean was off-centre and that intervention is required to adjust the location of the process mean. A process improvement strategy involving an adjustment to the automated process settings has demonstrated in principle that the process mean can be shifted closer to the centre of the specification to achieve an estimated seven-fold improvement in process performance. In practice, the 90% confidence bound estimate of Cp (Cp = 0.90) indicates that that once the process is centred within the specification, a further reduction of process variation is required to attain an automated process with the desired minimum capability requirement.

On the process capability of the solid free-form fabrication: a case study of scaffold moulds for tissue engineering

This study applies the methodology and procedure of process capability to investigate a solid free-form fabrication technique as a manufacturing method to produce scaffold moulds for tissue engineering. The process capability Cpk and process performance Ppk of scaffold mould manufacture using a solid free-form fabrication technique has been analysed with respect to the dimension deviations. A solid free-form fabrication machine T66 was used to fabricate scaffold moulds in this study and is able to create features that ranged from 200 microm to 1000 microm. The analysis showed that the printing process under the normal cooling conditions of the printing chamber was in statistical control but gave low process capability indices, indicating that the process was 'inadequate' for production of 'dimension-consistent' scaffold moulds. The study demonstrates that, by lowering the temperature of the cooling conditions, the capability Cpk of the printing process can be improved (about threefold) sufficiently to ensure the consistent production of scaffold moulds with dimension characteristics within their specification limits.

Current methods for the measurement of growth hormone in urine

Since the development of sensitive immunoassay procedures for the measurement of GH in urine, a urinary GH determination has been proposed as an alternative way of assessing pituitary GH secretion. Whilst studies on the clinical application of these assays have been difficult to correlate, for the reasons described, it is clear that an estimation of urinary GH has a useful role in clinical and physiological studies in both children and adults.

Urinary excretion and clearance of insulin in diabetic and normal children and adolescents

Seventy-two diabetic (38 males) and 86 normal (41 males) children provided timed overnight urine collections. Fourteen of the diabetic and 33 of the normal children had concurrent overnight plasma insulin profiles. Urinary insulin clearance in the diabetic subjects was compared with excretion of albumin, growth hormone, retinol-binding protein, and N-acetyl-beta-D-glucosaminidase. In the normal subjects, urinary insulin excretion correlated with mean overnight plasma levels in the boys (r = 0.82, p < 0.001) but not in the girls (r = 0.32), and varied with puberty stage in the boys. Insulin clearance was greater in boys than girls during puberty, and fell in both sexes with advancing puberty. Insulin excretion was greater in diabetic than normal children in both sexes at all puberty stages. Insulin clearance was also greater in diabetic than normal subjects (1.05 +/- 0.1 ml min-1 1.73 m-2 vs 0.48 +/- 0.05 ml min-1 1.73 m-2, p < 0.001). Insulin excretion as a percentage of the filtered load was also greater in diabetic than normal subjects (1.9 +/- 0.27% vs 0.85 +/- 0.09%, p < 0.01). In the diabetic children, there was a correlation between urinary insulin and growth hormone excretion (r = 0.52, p < 0.02), and retinol-binding protein in those (n = 10) with higher retinol binding protein excretion (r = 0.76, p = 0.01). The value of urinary insulin excretion as a measure of free plasma insulin levels in normal and diabetic children may be limited by sex differences in renal insulin clearance, and by proximal renal tubular dysfunction in children with diabetes.

Urinary growth hormone excretion during puberty in type 1 (insulin-dependent) diabetes mellitus

The excretion of urinary growth hormone was measured by a highly sensitive direct immunoradiometric assay in a cross-sectional study during puberty in 70 children with Type 1 (insulin-dependent) diabetes mellitus and 94 normal children. In normal children (n = 24) and diabetic children (n = 17) overnight urinary growth hormone excretion correlated significantly with the mean overnight plasma concentration (r = 0.70, p less than 0.001, and r = 0.70, p less than 0.001), indicating that urinary GH excretion reflects the circulating endogenous GH level. Overnight urinary growth hormone excretion increased during puberty. In normal and in diabetic children there was a peak in boys at genital stage 4 (both p less than 0.01), and in girls at breast stage 2 (both p less than 0.02). The diabetic children excreted more urinary growth hormone than the normal children at every pubertal stage. Excretion of albumin, retinol binding protein and N-acetyl-beta-D-glucosaminidase was measured in urine from 38 diabetic children. Urinary growth hormone correlated weakly with urinary albumin (r = 0.49, p less than 0.01), retinol binding protein (r = 0.42, p less than 0.01), and N-acetyl-beta-D-glucosaminidase (r = 0.43, p less than 0.01). Urinary GH excretion was not related to blood glucose control (HbA1) in boys (n = 31) or girls (n = 39). The measurement of urinary growth hormone provides an assessment of endogenous growth hormone during puberty in normal and diabetic children. However, caution must be exercised in interpreting urinary growth hormone data from diabetic patients with increased excretion of albumin and retinol binding protein.

Measurement of human growth hormone in urine: development and validation of a sensitive and specific assay

A specific solid-phase immunoradiometric assay (IRMA), optimized for maximum sensitivity, has been developed for measurement of human GH (hGH) in urine. The sensitivity varied with sample size, giving a range of 0.001 to 0.003 mU/l for a sample volume of 2 ml. Recovery and dilution experiments, together with chromatography of urine samples, indicate that the method is specific for hGH. Added exogenous hGH was measured with a mean recovery of 101 +/- 10% (S.D.) for 1 ml samples and 87 +/- 8% for 2 ml samples. Measurements of samples diluted at 1:2 and 1:4 gave values of 97.4 and 96.6% respectively of those expected. Cross-reactions of human placental lactogen and prolactin were less than 0.008 and 0.04% respectively on a mol/mol basis. The assay was insensitive to the presence of NaCl (50-500 mmol/l), urea (50-1000 mmol/l), creatinine (1-20 mmol/l), Ca2+ ions (1-20 mmol/l), SO4(2-) ions (1-1000 mmol/l), Mg2+ ions (0.05-50 mmol/l), 0.5-5% (w/v) glucose and a pH range of 6-9. Chromatography of unextracted samples showed that the immunoreactive material in urine eluted in a single homogenous peak with a similar position to monomeric pituitary hGH (22 kDa). Administered hGH (0.002%) was recovered in urine collected over a 2-h period following an intravenous injection. The urine output of hGH showed a good correlation with serum hGH in 18 patients following routine insulin tolerance tests and in 25 patients following an oral glucose tolerance test.(ABSTRACT TRUNCATED AT 250 WORDS)

Urinary growth hormone during puberty in normal and diabetic children

The measurement of GH in urine may have many clinical applications, particularly in childhood. We have used a highly sensitive direct immunoradiometric assay to examine urinary GH excretion in children during puberty. Fifty-five healthy schoolchildren collected timed overnight urine samples. A further 36 children (15 normal, six of short stature and 15 diabetic) collected urine samples during a total of 50 overnight plasma GH secretory profiles (15-min sampling). Overnight urinary GH excretion increased during puberty, with a peak at breast stage 2 in girls, and genital stage 4 in boys, before declining at stage 5. There was a positive correlation (r = 0.57, p = 0.003) with height velocity in girls, but not in boys. At each puberty stage except 2, the diabetics excreted more urinary GH than the normal children. There was a highly significant correlation (r = 0.79, p less than 0.001) between mean overnight plasma GH concentrations and urinary GH excretion, suggesting that the latter accurately reflects physiological GH secretion.