WMDA guidelines for subsequent donations following initial BM or PBSCs

Remuneration of donors for cell and gene therapies: an update on the principles and perspective of the World Marrow Donor Association

The cell and gene therapy (CGT) sector has witnessed significant advancement over the past decade, the inception of advanced therapy medicinal products (ATMPs) being one of the most transformational. ATMPs treat serious medical conditions, in some cases providing curative therapy for seriously ill patients. There is interest in pivoting the ATMP development from autologous based treatments to allogenic, to offer faster and greater patient access that should ultimately reduce treatment costs. Consequently, starting material from allogenic donors is required, igniting ethical issues associated with financial gains and donor remuneration within CGT. The World Marrow Donor Association (WMDA) established the Cellular Therapy Committee to identify the role WMDA can play in safeguarding donors and patients in the CGT field. Here we review key ethical principles in relation to donating cellular material for the CGT field. We present the updated statement from WMDA on donor remuneration, which supports non-remuneration as the best way to ensure the safety and well-being of donors and patients alike. This is in line with the fundamental objective of the WMDA to maintain the health and safety of volunteer donors while ensuring high-quality stem cell products are available for all patients. We acknowledge that the CGT field is evolving at a rapid pace and there will be a need to review this position as new practices and applications come to pass.

Is It Possible to be a Stem Cell Donor for the Second Time: A Single-Center Report of 12 Consecutive Procedures

OBJECTIVES

The use of unrelated donors as a source of stem cells for patients with blood disorders continues to increase. Approximately 5% to 7% of unrelated stem cell donors are asked to donate stem cells a subsequent time to the same or a different patient. We investigated donors who accepted to be a donor for the second time between 2015 and 2021; donors were evaluated in terms of procedure-related complications, product quality, and donor follow-up in a JACIEaccredited (Joint Accreditation Committee of the International Society for Cellular Therapy and European Society for Blood and Marrow Transplantation).

MATERIALS AND METHODS

Stem cell collections were performed in accordance with relevant standard operating procedures from healthy volunteer donors. Data on sequence of peripheral blood stem cell, bone marrow, and donor lymphocyte collection procedures; presence of complications during procedures; time between 2 donations; need for granulocyte colonystimulating factor again; and first and second donation types were noted. Data on donor and stem cell products were determined using the hospital information management system.

RESULTS

Our study included 12 donors (9 men and 3 women) who donated a second time within the specified date range. In the evaluation of the second donation types, 7 were lymphocyte collection donations, 4 were peripheral blood stem cell donations, and 1 was a bone marrow stem cell donation. In shortterm and long-term follow-ups, there were no complications among the donors. In the second donations, targeted product values were reached.

CONCLUSIONS

Although it is safe to have a second donation from a donor for the same patient, collection centers may collect more products than requested from eligible donors.

Shorter Interdonation Interval Contributes to Lower Cell Counts in Subsequent Stem Cell Donations

Approximately 7% of unrelated hematopoietic stem cell donors are asked to donate stem cells a subsequent time to the same or a different recipient. Recent studies have shown that donation-related symptoms for second donations are similar to those for the first donation. Little is known about differences in stem cell mobilization and yields for subsequent peripheral blood stem cell (PBSC) and bone marrow (BM) collections. We hypothesized that CD34⁺ cell yields and total nucleated cell (TNC) concentrations for subsequent PBSC or BM donations are lower than those at the first donation. We also evaluated the factors influencing stem cell yields in healthy unrelated second-time donors. Data were gathered from the Center for International Blood and Marrow Transplant Research database on 513 PBSC and 43 BM donors who donated a second time between 2006 and 2017 through the National Marrow Donor Program. Among the second-time PBSC donors, we found significantly lower preapheresis peripheral blood CD34⁺ cell counts (68.6 × 10⁶/L versus 73.9 × 10⁶/L; P = .03), and collection yields (556 × 10⁶ versus 608 × 10⁶; P = .02) at the second donation compared to the first. This decrease at the subsequent donation was associated with a shorter interdonation interval, lower body mass index (BMI), and a lower total G-CSF dose. In most instances, suboptimal mobilizers at their first donation donated suboptimal numbers of stem cells at their subsequent donations. Among repeat BM donors, the TNC concentration was lower at the second donation. The small size of this group precluded additional analysis. Overall, when considering repeat donations, increasing the interdonation intervals and evaluating for BMI changes should be considered to optimize stem cell yields. Some of these parameters may be improved by increasing G-CSF dose in PBSC donors within permissible limits.

Donor Evaluation for Hematopoietic Stem and Progenitor Cell Collection

With the increasing incidence of hematopoietic allogeneic cell transplantation (allo-HCT), the importance of securing a cellular product, safely from a donor, and ensuring that the product is without additional risk to the recipient, continues to be of paramount importance. The evaluation of the donor’s medical eligibility and suitability is designed to identify and limit the risk of transmitting infectious, genetic, or neoplastic diseases to the recipient through the product. It also aims to ensure a maximum level of safety for the donor and informs them of the risks of donation. Several regulatory agencies, national and international registries, and accreditation bodies have facilitated the availability and safe provision of human cells, tissues, and cellular- and tissue-based products not only at local institutions but also through international exchange.

Suitability Criteria for Adult Related Donors: A Consensus Statement from the Worldwide Network for Blood and Marrow Transplantation Standing Committee on Donor Issues

The number of allogeneic hematopoietic stem cell (HSC) transplants performed globally each year continues to increase. Advances in HLA typing, better supportive care, and administration of reduced-intensity conditioning regimens allow treatment of older patients with older sibling donors. Pretransplant donor assessment and testing are very important processes affecting the quality and safety of donation. For unrelated HSC donors detailed recommendations for health assessment have been published, allowing donation only if they are unrestrictedly healthy. Eligibility criteria for related donors are less strict and vary significantly between centers. In situations where a family donor does not meet the suitability criteria for unrelated donors, involved physicians often struggle with the decision whether the matched relative is suitable for donation or not. On behalf of the Worldwide Network for Blood and Marrow Transplantation Standing Committee on Donor Issues, we intended to develop a consensus document with recommendations for donor workup and final clearance of family donors who would not be able to serve as unrelated donors because of their age or pre-existing diseases. This article covers different topics intending to support decision-making, with the goal of minimizing medical risk to the donor and protection of the recipient from transmissible diseases.

Subsequent donation requests among 2472 unrelated hematopoietic progenitor cell donors are associated with bone marrow harvest

Approximately 1 in 20 unrelated donors are asked to make a second donation of hematopoietic progenitor cells, the majority for the same patient. Anthony Nolan undertook a study of subsequent hematopoietic progenitor cell donations made by its donors from 2005 to 2011, with the aims of predicting those donors more likely to be called for a second donation, assessing rates of serious adverse reactions and examining harvest yields. This was not a study of factors predictive of second allografts. During the study period 2591 donations were made, of which 120 (4.6%) were subsequent donations. The median time between donations was 179 days (range, 21-4016). Indications for a second allogeneic transplant included primary graft failure (11.7%), secondary graft failure (53.2%), relapse (30.6%) and others (1.8%). On multivariate analysis, bone marrow harvest at first donation was associated with subsequent donation requests (odds ratio 2.00, P=0.001). The rate of serious adverse reactions in donors making a subsequent donation appeared greater than the rate in those making a first donation (relative risk=3.29, P=0.005). Harvest yields per kilogram recipient body weight were equivalent between donations, although females appeared to have a lower yield at the subsequent donation. Knowledge of these factors will help unrelated donor registries to counsel their donors.

Safety and efficacy of healthy volunteer stem cell mobilization with filgrastim G-CSF and mobilized stem cell apheresis: results of a prospective longitudinal 5-year follow-up study

BACKGROUND AND OBJECTIVES

G-CSF-mobilized peripheral blood stem cells have long replaced marrow as the major source for allogeneic transplants. Conclusive evidence questioning the long-term safety of G-CSF for donors has not been provided, but the cumulative number of followed donors remains insufficient to rule out rare adverse events. A long-term active follow-up study of G-CSF-mobilized healthy volunteer donors was therefore performed.

PATIENTS AND METHODS

Two hundred and three successive donors were evaluated pre-apheresis, subjected to G-CSF-mobilization/apheresis, and actively followed for 5 years by the same physicians and laboratories. Follow-up laboratory work included standard biochemical/haematological tests and T-cell phenotyping.

RESULTS

Donor epidemiology was typical for reported stem cell donor cohorts. Acute adverse effects of G-CSF and apheresis were mild and transient, consistent with the previous reports. Mean circulating CD34(+) cells after nine doses of G-CSF were 124 per μl. Other biochemical/haematological parameters were also altered, consistent with G-CSF treatment. Spleen enlargement was modest. At first follow-up, all clinical and laboratory parameters had normalized. Leucocyte/lymphocyte counts and CD4/CD8 ratios were the same as during premobilization work-up and remained unchanged throughout. A single severe but likely unrelated adverse event, a case of papillary thyroid carcinoma, was reported.

CONCLUSION

The studies add an observation time of almost 500 donor years to the growing body of evidence of the long-term safety of G-CSF for allogeneic donor stem cell mobilization.

Screening of related donors and peripheral blood stem cell collection practices at different Italian apheresis centres

BACKGROUND

Recommendations on eligibility criteria for donation of haematopoietic stem cells, management of collection of the cells and follow-up mainly concern unrelated donors. The aim of this study was to analyse the screening of related donors and collection practices at different Italian apheresis centres.

MATERIALS AND METHODS

A questionnaire regarding eligibility criteria for related haematopoietic stem cell donors, their peripheral blood collections and early follow-up was sent to several apheresis units. Data from the full charts of 500 candidates, screened between May 2005 and December 2009, were retrospectively evaluated.

RESULTS

The donors' records, eligibility criteria, collections and follow-up are managed differently in each centre. Of the 500 evaluable candidates (51.2% male, 49.8% female; median age 47 years, range 13-77), 26.4% underwent thorough screening according to Italian Bone Marrow Donor Registry standards, while local protocols were applied to 73.6%; 91 candidates (18.2%) proved ineligible for donation. In the end, 352 donors (53.4% male, 46.6% female; median age 45 years, range 16-76) underwent 508 leukaphereses. Central venous catheters were used in 8.0% of donors, mainly in one centre. Unsuitable pre-apheresis peripheral blood parameters were reported in 38.7% of the aphereses. Leukapheresis-related adverse events were recorded in 23.0% of the procedures, with a drop-out rate of 0.2% for severe events. No donation-related fatalities occurred. The CD34+ cell yield was <2×10(6)/kg of recipient's body weight from 1.1% of donors ≥70 years old.

DISCUSSION

More uniformity in donor screening procedures, management of peripheral blood collection and follow-up should be planned at a national level to maximise the safety of related donors.

Allogeneic hematopoietic stem cell donation-standardized assessment of donor outcome data: a consensus statement from the Worldwide Network for Blood and Marrow Transplantation (WBMT)

The number of allogeneic hematopoietic SCTs performed globally each year continues to increase, paralleled by an increased demand for donors of therapeutic cells. Donor characteristics and collection procedures have undergone major changes during recent decades, and further changes are foreseen. Information on short- and long-term donor outcomes is of crucial importance to ensure maximal donor safety and availability. Current data, predominantly from unrelated donors, give reliable information on the frequent early events associated with donation-most of them of mild-to-moderate intensity. Information on the type and relative risk of serious adverse reactions is more limited. Moreover, only few data exist on long-term donor outcome. On the basis of this need, recommendations for a minimum data set for prospective donor follow-up were developed in a workshop with the participation of an international group of investigators actively involved in allogeneic stem cell donation under the auspices of and approved by the Worldwide Network for Blood and Marrow Transplantation. Establishment of a standardized global follow-up for both, related and unrelated, donors will enable monitoring of the short- and long-term safety profiles of hematopoietic cell donation and form a solid basis for future donor selection and counseling.