Planning Split-Apheresis Designs for Demonstrating Comparability of Cellular and Gene Therapy Products.

A recent FDA draft guidance discusses statistical considerations for demonstrating comparability of cell and gene therapy products and processes. One experimental study described in the guidance is the split-apheresis design. The FDA draft guidance recommends a paired data analysis for such a design. This paper demonstrates that the paired analysis is under powered for some quality attributes for practical sample sizes of three to five donors unless a significant portion of variability is attributed to donor. Addition of historic lots from the pre-change process can increase the power for these attributes. This paper provides appropriate statistical methods for including this information.

Preemptive Approach to Plerixafor Use Is Optimal in Patients With Relapsed/Refractory Germ Cell Tumors Undergoing Peripheral Blood Hematopoietic Stem Cell Collection: Effect on Collection Days, Yields, and Cost.

Evidence describing the use of plerixafor in the off-label population of relapsed/refractory germ cell tumors (GCT) is limited. We aim to describe the effect of rescue versus preemptive plerixafor use on apheresis collection days, collection yields, and cost. We retrospectively collected data on 77 consecutive patients (at least 15 years of age) with GCT who underwent peripheral blood stem cell (PBSC) collection for autologous stem cell transplant between January 1, 2020 and May 1, 2022. Depending on insurance approval, plerixafor was given either as "rescue" (after a first apheresis collection of < 5 × 106 CD34+ cells/kg) or as "preemptive" on Day 4 of granulocyte-colony stimulating factor (G-CSF) prior to the first apheresis collection, if the Day 4 peripheral blood CD34+ count was < 40 cells/µL. A total of 66% of patients who received preemptive plerixafor completed collection in 1 day, similar to good mobilizers who only needed G-CSF (71%, p = 0.366). In contrast, all poor mobilizers in the rescue group required at least 2 days of collection and had lower CD34+ cell yields than the preemptive group (7.15 vs. 9.81 × 106/kg, p = 0.0055). A cost analysis revealed that preemptive plerixafor may save approximately $7000 per patient compared with a rescue approach. Preemptive plerixafor in GCT patients undergoing PBSC collection allows relatively poor mobilizers to collect in fewer days and with lower overall cost. Fewer apheresis procedures result in less risk to the patient, increased patient satisfaction, and the ability to schedule more patients within the constraints of staffing.

Acoustofluidic-based therapeutic apheresis system.

Therapeutic apheresis aims to selectively remove pathogenic substances, such as antibodies that trigger various symptoms and diseases. Unfortunately, current apheresis devices cannot handle small blood volumes in infants or small animals, hindering the testing of animal model advancements. This limitation restricts our ability to provide treatment options for particularly susceptible infants and children with limited therapeutic alternatives. Here, we report our solution to these challenges through an acoustofluidic-based therapeutic apheresis system designed for processing small blood volumes. Our design integrates an acoustofluidic device with a fluidic stabilizer array on a chip, separating blood components from minimal extracorporeal volumes. We carried out plasma apheresis in mouse models, each with a blood volume of just 280 µL. Additionally, we achieved successful plasmapheresis in a sensitized mouse, significantly lowering preformed donor-specific antibodies and enabling desensitization in a transplantation model. Our system offers a new solution for small-sized subjects, filling a critical gap in existing technologies and providing potential benefits for a wide range of patients.

Analysis of apheresis outcomes in a cohort of Chilean patients treated with autologous stem cell transplantation: A single center real-world experience.

Adequate stem cell harvesting is required for autologous hematopoietic transplantation. In deficient mobilizer patients, the collection of stem cells can be challenging because of the impossibility of achieving satisfactory CD34 cell counts with GCSF + - chemotherapy. Plerixafor is a potent and expensive drug that promotes the release of stem cells from the medullary niche to the peripheral blood and allows satisfactory harvests. We performed a retrospective analysis of 370 patients with myeloma and lymphoma harvested at our institution. 99 % of patients achieved satisfactory apheresis using Plerixafor in 45 %. Satisfactory harvests were obtained in patients mobilized with GCSF or plerixafor. In patients who used plerixafor, it was necessary to perform fewer apheresis procedures (P = 0.05). In multivariate analysis, the only factor that predicted the need for plerixafor was the presence of less than 30,000 CD34 / ul on the day of apheresis (OR 0.3. p < 0.001). Since we adopted the plerixafor protocol guided by CD34 counts, the number of patients with harvest failure has decreased. In conclusion, the rational and standardized use of plerixafor favors satisfactory harvest in patients who require autologous transplantation in South-American patients.

Use of a novel configuration of ports for patients needing intermittent long-term apheresis.

PURPOSE: In patients with a need for frequent but intermittent apheresis, vascular access can prove challenging. We describe the migration of the use of a Vortex LP dual lumen port (Angiodynamics, Latham, NY) to one Powerflow and one ClearVUE power injectable port (Becton Dickinson, Franklin Lakes, NJ) in a series of patients undergoing intermittent apheresis. MATERIALS AND METHODS: All patients had a need for long-term intermittent apheresis. Eight had double lumen Vortex port (pre) and were exchanged for one Powerflow port and one conventional subcutaneous venous port with 90° needle entry (post) while 12 did not have any port in place and received the same configuration. IRB approval was granted. We recorded the treatment time, flow rate, and tissue plasminogen activator (tPA) use for five treatment sessions after placement. When available, we compared five treatments with the Vortex port and the new configuration. RESULTS: The mean treatment time is reduced with the new configuration (P = 0.0033). The predicted mean treatment time, adjusting for gender, race, BMI and age and accounting for correlations within a patient is 91.18 min pre and 77.96 min post. The flow rate is higher with the new configuration (P < 0.0001). The predicted mean flow rate in mL/min is 61.59 for the Vortex port and 71.89 for the new configuration. tPA use was eliminated in the population converted from Vortex ports and had a 48% reduction when compared to all other configurations in the study. CONCLUSION: The introduction of a novel device configuration of venous access ports for intermittent apheresis resulted in higher flow rates and less total time for treatment. Use of tPA was greatly reduced. These results suggest that the new configuration could result in less expense for the hospital and better throughput in a busy pheresis practice. Clinical trial registration with ClinicalTrials.gov: NCT04846374.

Effects of Rheopheresis in dialysis patients with peripheral artery disease and diabetic foot ulcers: A multicentric Italian study.

BACKGROUND: Peripheral artery disease (PAD) in hemodialysis (HD) patients has a significant social impact due to its prevalence, poor response to standard therapy and dismal prognosis. Rheopheresis is indicated by guidelines for PAD treatment. MATERIALS AND METHODS: Twenty-five HD patients affected by PAD stage IV Lerichè-Fontaine and ischemic ulcer 1C or 2C according to the University of Texas Wound Classification System (UTWCS), without amelioration after traditional medical therapy and/or revascularization, were selected and underwent 12 Rheopheresis sessions in 10 weeks. Improvements in pain symptoms using Numerical Rating Scale (NRS), healing ulcers and laboratory hemorheological parameters have been evaluated. RESULTS: A clinically and statistically significant mean value reduction and of relative percentage differences between estimated marginal means (Δ), calculated at each visits, of NRS was observed, with a maximum value (-48.5%) between the first and last visit. At the end of the treatment period 14.3% of ulcers were completely healed, 46.4% downgraded, 53.6% were stable. Overall, no ulcers upgraded. A statistically significant reduction of the Δ, between the first and last visit, for fibrinogen (-16%) was also observed. CONCLUSION: Rheopheresis reduced overall painful symptoms; data suggest that it could heal or improve ulcers and hemorheological laboratory parameters in HD patients with PAD and ischemic ulcers resistant to standard therapies.

Lipid apheresis in the management of severe hypertriglyceridaemia in an adolescent girl with global developmental delay.

Hypertriglyceridaemia-induced acute pancreatitis (HTG-AP) remains one of the common metabolic causes of acute pancreatitis in the paediatric population and the third most common cause after alcohol and gallstones in the adult population. We report a case of an early adolescent girl with global developmental delay and moderate cognitive impairment of unknown aetiology who presented with recurrent acute pancreatitis and uncompensated hypovolaemic shock. She was found to have serum triglyceride level of 7877 mg/dL (reference range<150 mg/dL) and hyperglycaemia with ketosis (no prior history of diabetes mellitus) that was successfully treated with lipid apheresis. This sometimes is an early modality for treatment in adults; however, it remains a last resort in children, used only for severe cases. A brief literature review on severe HTG-AP and its management is also provided.

Apheresis product total CD34+ cell count prediction at peripheral stem cell collection via a formula: A multicenter study.

INTRODUCTION: Effective mobilization of Stem Cells(SCs) to peripheral blood (PB) is crucial for obtaining sufficient CD34+ cell numbers via apheresis. The ratio of pre-apheresis PB CD34+ cells is the best parameter for predicting the product CD34+ cell count. However, quantitating CD34+ PB cells requires flow cytometry, which usually takes two or more hours to obtain the results. We hypothesized that the product CD34+ cell count could be predicted using the counts of white blood cells (WBCs), mononuclear cells (MNCs), and pre-apheresis CD34+ cells. A formula that achieves this would substantially affect the efficiency and effectiveness of apheresis. We, therefore, aimed to estimate the number of CD34+ cells in the product using a formula that incorporates pre-apheresis PB WBC, MNC, and CD34+ cell counts and product WBC and MNC counts. METHODS: We examined the results of 373 leukapheresis procedures for SC mobilization. Effective separation of CD34+ PBSCs (count/µL) via apheresis was estimated using the following formula: [Product WBC (count/µL) × MNC (count/µL) × pre-apheresis CD34+ cell (percentage/µL)] ÷ [PB WBC count/µL × PB MNC (count/µL)]. RESULTS: A strong correlation was observed between the CD34+ cell count calculated using our formula and the post-apheresis CD34+ cell count measured via flow cytometry (R = 0.939, based on linear regression analysis). In the subgroup analysis, this correlation was observed for all the disease subgroups and healthy donors. CONCLUSION: We developed a formula that predicts the product CD34+ cell count and is useful for determining whether a second apheresis procedure will be required.

Telapheresis: One institution's experience.

Telemedicine in its most common form is the use of videoconferencing to consult with a patient and telapheresis is telemedicine in the form of videotelephony applied to consult with a patient for apheresis. The article discusses how a large apheresis program in a metropolitan area provided physician coverage for apheresis in a more remote hospital using telapheresis with local physician "partners" and local nurses employed by and trained by the apheresis program that perform the procedure. Consent for the procedure was obtained, and orders were placed by the local physician after consultation with the apheresis physician, or the apheresis physician him/herself, having obtained privileges at the remote hospital. This allowed patients access to apheresis procedures nearer to their place of residence and in familiar surroundings which generally made them feel more positive about their health care experience.

A multi-institutional survey of apheresis services among institutions in the United States.

INTRODUCTION: Apheresis practices in the United States (US) have not been comprehensively characterized to date. This study aimed to address this gap by evaluating apheresis therapy through a national survey. METHODS: A multi-institutional survey was conducted between April and July 2023. The survey, comprising 54 questions, focused on institutional demographics, procedures, equipment, staffing, training, and impacts of the Coronavirus Disease 2019 (COVID-19) pandemic. Responses from 22 institutions, primarily academic medical centers, were analyzed. RESULTS: Therapeutic plasma exchange (TPE) was the most common procedure, followed by hematopoietic progenitor cell collection (HPC-A) and red blood cell exchange (RCE). CAR-T cell collections were widespread, with some institutions supporting over 30 protocols concurrently. Most sites used the Spectra Optia Apheresis System, were managed by a transfusion medicine service, and employed internal apheresis providers. Insufficient staffing levels, exacerbated by the COVID-19 pandemic, were common and most often addressed using overtime. DISCUSSION: The survey highlighted the ubiquity of TPE, expanding cellular collections and staffing challenges. The role of apheresis in supporting cellular therapy, particularly in newly developing cell and gene therapies and clinical trials, was evident. Staffing issues during the pandemic emphasized the need for innovative recruitment strategies. CONCLUSION: This nationwide survey provides the most comprehensive analysis to date of apheresis practices in large US academic centers.

Small but mighty: Case report and practical guidance for peripheral blood stem cell collection in small infants.

Modern apheresis devices, with increased procedural precision, automation, and monitoring, have been shown to allow for safe delivery of apheresis therapies in young children. Medical advances are increasing demand for apheresis procedures like mononuclear cell collection in infants <10 kg, including stem-cell supported chemotherapy, cell collection for chimeric antigen receptor T cell development, and now ex vivo gene therapies for rare genetic diseases. Nevertheless, safe delivery in small infants involves a range of unique considerations and challenges, beyond just size, and experience will vary between centers. In this case report we describe our experience performing mononuclear cell collection in our smallest patient to date and outline a practice guideline developed following a literature review and discussion with both international experts and device representatives. This case may help to inform other clinicians aiming to provide apheresis care to very small infants in their own centers.

Immunological and therapeutic insights in autoimmune autonomic ganglionopathy: What is the position of apheresis in immunotherapy?

Autoimmune autonomic ganglionopathy (AAG) is characterized by various autonomic and extra-autonomic symptoms and is caused by autoantibodies against nicotinic acetylcholine receptors present in the autonomic ganglia (ganglionic acetylcholine receptor, gAChR), requiring immediate and aggressive intervention to prevent the exacerbation of symptoms. However, there is currently no internationally accepted standard of care for the immunotherapy of AAG, including apheresis. Although the rationale for the use of plasma exchange (PLEX) in AAG is strong, whereby pathogenic gAChR antibodies are removed, its overall impact on patient outcomes is not well-established. Based on previous case reports and small case series studies, we provide a comprehensive overview of the challenges and uncertainties surrounding the use of PLEX for the management of AAG and provide current practice recommendations to guide treatment decisions.

The efficacy of erythrocyte apheresis for treatment of secondary erythrocytosis: An observational study.

To evaluate the efficacy of erythrocyte apheresis on the treatment of secondary erythrocytosis. Patients with secondary erythrocytosis who had visited the Department of Hematology at the Qinghai University Affiliated Hospital between January 2021 and May 2022 were enrolled. Based on the treatment method used, the patients were divided into erythrocytapheresis group and bloodletting group. In total, 50 patients were treated using a hemocyte separator and 36 patients were treated with bloodletting. The outcomes of 2 groups were compared. Compared with the bloodletting group, the clinical symptoms improved, blood routine indicators such as RBC, Hb, and HCT significantly reduced, and the progression rate was lower in the erythrocytapheresis group. Erythrocytic apheresis is effective and safe for the treatment of secondary erythrocytosis.

CD34+ cell yield among healthy donors: Large-scale model development and validation.

BACKGROUND: Successful engraftment in hematopoietic stem cell transplantation necessitates the collection of an adequate dose of CD34+ cells. Thus, the precise estimation of CD34+ cells harvested via apheresis is critical. Current CD34+ cell yield prediction models have limited reproducibility. This study aims to develop a more reliable and universally applicable model by utilizing a large dataset, enhancing yield predictions, optimizing the collection process, and improving clinical outcomes. MATERIALS AND METHODS: A secondary analysis was conducted using the Center for International Blood and Marrow Transplant Research database, involving data from over 17 000 healthy donors who underwent filgrastim-mobilized hematopoietic progenitor cell apheresis. Linear regression, gradient boosting regressor, and logistic regression classification models were employed to predict CD34+ cell yield. RESULTS: Key predictors identified include pre-apheresis CD34+ cell count, weight, age, sex, and blood volume processed. The linear regression model achieved a coefficient of determination (R2) value of 0.66 and a correlation coefficient (r) of 0.81. The gradient boosting regressor model demonstrated marginally improved results with an R2 value of 0.67 and an r value of 0.82. The logistic regression classification model achieved a predictive accuracy of 96% at the 200 × 106 CD34+ cell count threshold. At thresholds of 400, 600, 800, and 1000 × 106 CD34+ cell count, the accuracies were 88%, 83%, 83%, and 88%, respectively. The model demonstrated a high area under the receiver operator curve scores ranging from 0.90 to 0.93. CONCLUSION: This study introduces advanced predictive models for estimating CD34+ cell yield, with the logistic regression classification model demonstrating remarkable accuracy and practical utility.

Personalized autologous stem cell harvesting improves patient collection outcomes.

OBJECTIVES: This study aims to demonstrate that utilizing a personalized approach to apheresis stem cell collection, can safely optimize the collection outcomes, especially in the context of poor mobilizers and high cell targets. BACKGROUND: The optimal mobilization and harvesting of peripheral blood stem cells is critical to the success of the stem cell transplant. The ideal strategy that promotes better cell yields, with sustainable use of resources and assuring patient safety, should be pursued. METHODS: PBSC collections for autologous stem cell transplant data according to a fixed-processed volume strategy (One Size Fits All) or individualized to patients CD34+ peripheral blood content and target approach (Custom-Tailored or CT) were retrospectively compared. RESULTS: A total of 263 collections from 142 patients were assessed. The majority of patients were male, had multiple myeloma and were mobilized with isolated G-CSF. The CT strategy promoted a significantly higher CD34+ cell yield when the pre-collection CD34 was lower than 20/µl (1.02 ± 0.16 versus 1.36 ± 0.23, p < 0.001) and also a decrease in the proportion of mobilization cycles that needed 3 apheresis (31% versus 14%, p = 0.02). There was no difference in apheresis-related adverse events between the groups. CONCLUSION: Tailoring the apheresis procedures to the patient-specific characteristics and objectives, can effectively promote better patient outcome.

Optimizing autologous stem cell collections for patients with multiple myeloma receiving G-CSF and Plerixafor: A single center project.

BACKGROUND: Increasing indications for cellular therapy collections have stressed our healthcare system, with autologous collections having a longer than desired wait time until apheresis collection. This quality improvement initiative was undertaken to accommodate more patients within existing resources. STUDY DESIGN AND METHODS: Patients with multiple myeloma who underwent autologous peripheral blood stem cell collection from October 2022 to April 2023 were included. Demographic, mobilization, laboratory, and apheresis data were retrospectively collected from the medical record. RESULTS: This cohort included 120 patients (49.2% male), with a median age of 60 years. All received G-CSF and 95% received pre-emptive Plerixafor approximately 18 hours pre-collection. Most (79%) had collection goals of at least 8 × 106/kg CD34 cells, with 63% over 70 years old having this high collection goal (despite 20 years of institutional data showing <1% over 70 years old have a second transplant). With collection efficiencies of 55.9%, 44% of patients achieved their collection goal in a single day apheresis collection. A platelet count <150 × 103/µL on the day of collection was a predictor for poor mobilization; among 27 patients with a low baseline platelet count, 17 did not achieve the collection goal and 2 failed to collect a transplantable dose. CONCLUSIONS: With minor collection goal adjustments, 15% of all collection appointments could have been avoided over this 6-month period. Other strategies to accommodate more patients include mobilization modifications (Plerixafor timing or substituting a longer acting drug), utilizing platelet counts to predict mobilization, and modifying apheresis collection volumes or schedule templates.

Apheresis treatment in autoimmune neurological diseases: Predictors of good clinical outcome and success of follow-up therapy with B-cell depletion.

OBJECTIVE: Apheresis treatment (AT) is an established standard of treatment in various neurological autoimmune diseases. Since not all patients equally benefit from AT, we saw the need to investigate the effect of different clinical, paraclinical and technical-apparative factors on the clinical outcome. Additionally, we wanted to find out whether patients who improved due to AT continue to be clinically stable under B-cell depletion (BCD). METHODS: We screened all patients (n = 358) with neurological diseases who received AT at the Medical center of the University of the Saarland in the past 20 years. Different factors (e.g., age, sex, duration until onset of AT, type of AT, number of cycles, csf parameters) were analyzed retrospectively. Clinical disability was measured using the modified Rankin scale (mRS), visual acuity and the Expanded Disability Status Scale (EDSS). RESULTS: 335 patients, categorized into 11 different autoimmune diagnosis groups, received a total of 2669 treatment cycles and showed a statistically significant improvement in mRS with AT (p < 0.001). Patients in American Society for Apheresis (ASFA) categories I (p = 0.013) and II (p = 0.035) showed a significantly greater benefit under AT than those in category III. The clinical outcome was better with shorter duration until AT onset, more cycles of AT, and more plasma volume exchanged and the presence of an autoimmune antibody. Patients who initially profited had a significantly more stable course of the disease after 1-Year-BCD (p = 0.039). DISCUSSION: In the present study, we were able to identify various significant factors influencing the outcome of patients due to AT. Furthermore, we could show that patients with a response to AT can benefit from BCD follow-up therapy.

Comparison of double-filtration plasmapheresis (DFPP) versus heparin-mediated extracorporeal LDL-precipitation (HELP)-apheresis in early-onset preeclampsia.

OBJECTIVES: Preeclampsia (PE) is a major cause of maternal and fetal mortality, and preterm birth. Previous studies indicate that lipid-apheresis may prolong pregnancy, namely heparin-mediated extracorporeal LDL-precipitation (HELP)- and dextran sulfate cellulose (DSC)-apheresis. We now report on double membrane plasmapheresis (DFPP) in early-onset preeclampsia (eoPE). STUDY DESIGN: Open pilot study assessing the prolongation of pregnancy in PE by lipoprotein-apheresis (DRKS00004527). Two women with eoPE were treated by DFPP and compared to a historical cohort of 6 patients with eoPE treated by HELP-apheresis (NCT01967355). MAIN OUTCOME MEASURES: Clinical outcome of mothers and babies and prolongation of pregnancies (time of admission to birth). RESULTS: Patient 1 (33y; 22 + 5/7GW) received 4 DFPP. Delivery day 19; birthweight 270 g; weight at discharge 2134 g on day 132. Patient 2 (35y; 21 + 4/7GW) received 2 DFPP. Delivery day 19; birthweight 465 g; weight at discharge 2540 g on day 104. DFPP was well tolerated by both patients. CONCLUSIONS: DFPP proved to be save and pregnancies remained stable as long as 19 days. Although babies were born very preterm both babies could finally be dismissed from hospital. No relevant clinical differences between DFPP and HELP-apheresis could be observed. Therefore, DFPP may extend the range of available apheresis techniques to prolong pregnancies in early-onset preeclampsia. However, further studies are necessary to gain more information. REGISTER: (DRKS00004527).