Platelet Reduction Research Articles

Abstract 5925: Safety, efficacy, pharmacokinetics, and pharmacodynamics of a second generation Irofulven analog CAP-0121 in preclinical cancer models

Abstract Background: Irofulven is a semisynthetic sesquiterpene anticancer agent initially investigated for its unique mechanism of action and potential to overcome resistance observed in other chemotherapeutics. This study investigates the pharmacokinetics and pharmacodynamics of a second generation irofulven analog, CAP-121 (Califia Pharma), and its efficacy and safety in preclinical cancer models relative to irofulven. Methods: 24-hour comprehensive PK was performed at two different intravenous (IV) doses in canines for irofulven (0.2 mg/kg and 1 mg/kg; MTD) and CAP-121 (1 mg/kg and 3 mg/kg). Plasma concentrations were measured by ultra-high performance liquid chromatography multiple reaction monitoring mass spectrometry. PK parameters were determined for both compounds using noncompartmental methods (Phoenix WinNonlin, version 8.4). PK parameters included area under the concentration vs time curve (AUC), maximum observed concentration (Cmax), clearance (CL), volume of distribution (Vd), and elimination half-life (t1/2). Canine platelet and neutrophil counts were measured across 28 days to ascertain the maximum tolerated dose (MTD); platelet count reversibility was also assessed. Mice xenograft models implanted with a drug resistant human ovarian cancer (A2870), or a drug-resistant human metastatic lung cancer (MV522), were dosed with irofulven (9 mg/kg; MTD) and CAP-121 (15, 20, and 25 mg/kg) and resulting tumor mass, % change in body weight, and platelet counts were compared relative to vehicle only. Results: Systemic exposure, CL, Vd, and t1/2 were similar between irofulven and CAP-121 at a 1 mg/kg IV dose. For irofulven, exposure increased approximately proportionally at doses of 0.2 mg/kg and 1 mg/kg. For CAP-121, exposure increased less than proportionally at doses of 1 mg/kg and 3 mg/kg. MTD of CAP-121 was found to be 3-fold higher in canines compared to irofulven as 3-fold more CAP-121 was required to match the platelet reduction with irofulven; platelet nadir was rapidly reversible for CAP-121. Canine nadir platelets were 3-fold higher for CAP-121 vs irofulven at the same dose (1 mg/kg). CAP-121 was superior to irofulven (p < 0.02) with regards to final tumor weights in mice xenograft models, even though MTD was not reached for CAP-121; a change in body weight and platelet loss was not observed for CAP-121 at up 25 mg/kg in mice. Conclusion: The canine PK/PD study of CAP-121 demonstrates that CAP-121 has favorable PK parameters. With regards to in vivo anticancer cytotoxic activity, the two drug-resistant xenograft models confirm the superiority of CAP-121 over irofulven. Together, these findings indicate a wider therapeutic window in humans is expected for CAP-121 compared to irofulven, emphasizing the potential anticancer utility of CAP-121 for solid cancers without prolonged thrombocytopenia. Further investigation in clinical trials is warranted Citation Format: Raymond T. Suhandynata, T K. Nguyen, Venkata R. Kotamraju, Jeremiah D. Momper, Michael J. Kelner. Safety, efficacy, pharmacokinetics, and pharmacodynamics of a second generation Irofulven analog CAP-0121 in preclinical cancer models [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 5925.

Predicting the Long-Term Effects of Therapeutic Neutralization of Oncostatin M on Human Hematopoiesis.

Therapeutic neutralization of Oncostatin M (OSM) causes mechanism-driven anemia and thrombocytopenia, which narrows the therapeutic window complicating the selection of doses (and dosing intervals) that optimize efficacy and safety. We utilized clinical data from studies of an anti-OSM monoclonal antibody (GSK2330811) in healthy volunteers (n = 49) and systemic sclerosis patients (n = 35), to quantitatively determine the link between OSM and alterations in red blood cell (RBC) and platelet production. Longitudinal changes in hematopoietic variables (including RBCs, reticulocytes, platelets, erythropoietin, and thrombopoietin) were linked in a physiology-based model, to capture the long-term effects and variability of therapeutic OSM neutralization on human hematopoiesis. Free serum OSM stimulated precursor cell production through sigmoidal relations, with higher maximum suppression (Imax) and OSM concentration for 50% suppression (IC50) for platelets (89.1% [95% confidence interval: 83.4-93.0], 6.03 pg/mL [4.41-8.26]) than RBCs (57.0% [49.7-64.0], 2.93 pg/mL [2.55-3.36]). Reduction in hemoglobin and platelets increased erythro- and thrombopoietin, respectively, prompting reticulocytosis and (partially) alleviating OSM-restricted hematopoiesis. The physiology-based model was substantiated by preclinical data and utilized in exploration of once-weekly or every other week dosing regimens. Predictions revealed an (for the indication) unacceptable occurrence of grade 2 (67% [58-76], 29% [20-38]) and grade 3 (17% [10-25], 3% [0-7]) anemias, with limited thrombocytopenia. Individual extent of RBC precursor modulation was moderately correlated to skin mRNA gene expression changes. The physiological basis and consideration of interplay among hematopoietic variables makes the model generalizable to other drug and nondrug scenarios, with adaptations for patient populations, diseases, and therapeutics that modulate hematopoiesis or exhibit risk of anemia and/or thrombocytopenia.

Platelet Reduction after Transcatheter Aortic Valve Implantation: Results from the PORTRAIT Study.

Background: An unexplained condition that follows transcatheter aortic valve implantation (TAVI) is platelet count reduction (PR). According to published research, patients with balloon-expandable valves (BEVs) had a greater PR than those with self-expandable valves (SEVs). Objectives: The purpose of this study was to investigate the incidence and clinical effects of PR following TAVI. Methods: In total, 1.122 adult TAVI patients were enrolled. Propensity score matching was carried out in a 1:1 ratio between patients with BEVs and those with SEVs. The analysis included changes in platelet count, in-hospital mortality, and early postoperative adverse events. Results: Notably, 632 patients were matched (BEV:316; SEV:316). All patients' post-procedural platelet counts changed according to a parabolic curve, using a mixed regression model for repeated analyses (estimate = -0.931; standard error = 0.421; p = 0.027). The platelet count varied comparably in patients with BEVs and SEVs (estimate = -4.276, standard error = 4.760, p = 0.369). The average time for obtaining the nadir platelet count value was three days after implantation (BEV: 146 (108-181) vs. SEV: 149 (120-186); p = 0.142). Overall, 14.6% of patients (92/632) had post-procedural platelet count <100,000/µL. There was no difference between the two prosthesis types (BEV:51/316; SEV:41/316; p = 0.266). Thrombocytopenia was found to be significantly linked to blood product transfusions, lengthier stays in the intensive care unit and hospital, and in-hospital mortality. Conclusions: TAVI, irrespective of the type of implanted valve, is linked to a significant but temporary PR. Thrombocytopenia increases the risk of serious complications and in-hospital death in TAVI patients. To explore and clarify the causes and associated effects, further prospective research is necessary.

Hematological Indices in COVID-19 Patients with Rhinosinusitis Mucormycosis.

Rhinosinusitis mucormycosis (RM) is an invasive opportunistic fungal infection, especially among COVID-19 patients. The current study aimed to assess the peripheral blood hematological disorders of COVID-19 patients-associated RM. During ten month, in two COVID-19 centers in Mashhad, Iran, from June 2021 to March 2022, eighty-three patients suspected of COVID-19 with rhinosinusitis or rhino-orbital mucormycosis participated in this study. The hematological indices of these patients were measured by independent sample T-test or Mann-Whitney test for quantitative data, and the qualitative variables were analyzed using Chi-square or Fisher's exact test in SPSS version 20 at a significance level of 0.05. Of the COVID-19 patients, 40 (48.2%) were affected by RM, and leukocytosis due to neutrophilia was observed in 30% of them. Leukocyte counts were normal in 10 (25%) patients, but 1 (2.5%) and 3 (7.5%) had leukopenia and lymphopenia, respectively. Leukocytosis plus lymphopenia was observed in 7 (17.5%) patients. Also, the synchronicity of leukopenia and lymphopenia was seen in 5 (12.5%) patients. Leukopenia, lymphopenia, and neutropenia have occurred concurrently in 2 (5%) patients. The complete blood count (CBC) showed that RBCs, hemoglobin (Hb), hematocrit (HCT), MCH, MCHC, platelet (PLT), and lymphocytes decreased while neutrophils increased. Among the hematological parameters, leukocytosis due to neutrophilia and reduction in Hb, HCT, and PLT are more dominant factors in COVID-19 patients-associated RM.

Comparing transfusion reactions between pre-storage and post-storage leukoreduced apheresis platelets: an analysis using propensity score matching

Transfusion reactions induced by platelet transfusions may be reduced and alleviated by leukocyte reduction of platelets. Although leukoreduction of apheresis platelets can be performed either pre-storage or post-storage, seldom studies directly compare the incidence of transfusion reaction in these two different blood products. We conducted a retrospective study to compare the transfusion reactions between pre-storage and post-storage leukoreduced apheresis platelets. We reviewed the general characteristics and the transfusion reactions, symptoms, and categories for inpatients who received pre-storage or post-storage leukoreduced apheresis platelets. Propensity-score matching was performed to adjust for baseline differences between groups. A total of 40,837 leukoreduction apheresis platelet orders were reviewed. 116 (0.53%) transfusion reactions were reported in 21,884 transfusions with pre-storage leukoreduction, and 174 (0.91%) reactions were reported in 18,953 transfusions with post-storage leukoreduction. Before propensity-score matching, the odds ratio for transfusion reactions in the pre-storage group relative to the post-storage group was 0.57 (95% confidence interval [CI] 0.45–0.72, P < 0.01); the odds ratio after matching was 0.63 (95% CI 0.49–0.80, P < 0.01). A two-proportion z-test revealed pre-storage leukoreduction significantly decreases the symptoms of chills, fever, itching, urticaria, dyspnea, and hypertension as compared with those in post-storage leukoreduction. Pre-storage leukoreduced apheresis platelet significantly decreased febrile non-hemolytic transfusion reaction as compared with post-storage groups. This study suggests pre-storage leukoreduction apheresis platelet significantly decreases the transfusion reaction as compared with those in post-storage leukoreduction.

Study on some enzymatic, hematologic and oxidative stress markers of leukemic variants

The requirements of additional insight on the knowledge of Leukemia were a driving impetus for this study. The expression of a myriad of circulating markers elucidates the pathological state in various types of Leukemia. Elevated oxidative stress with concomitant reduction in antioxidant factors are key indices having a nexus with Leukemic abnormalities. In this research we examined these markers in 100 participants in which 75 were Leukemic patients and 25 were normal subjects. The Leukemic subjects were further differentiated based on some parameters evaluated using spectrophotometric and microscopic methods. Results show a significant elevation of MDA in disease variants (all - b = 9.3 + 1.25; all - t = 9.88 + 0.87; aml = 9.2 + 1.57 nM/ml) as compared to the controls that gave (2.12 + 0.02 nM/ml); P 0.05). While there was a reduction in platelets and Vitamin E levels, there was marked increase in ESR and leucocyte count. These results are indicative of a stressed state in Leukemia. Knowledge of these biomarkers could enhance management efforts at confronting this disease condition.

Durable Attenuation of Tumor pH-Platelet Linkage Reinstates Bioorthogonal Targeting of Residual Tumors Post-Debulking.

There are circumstances where tumors can only be partially resected. Therefore, multimodality therapy targeting post-operative residuals is important. Here, we show that bioorthogonal click chemistry enables targeted delivery to heterogeneous tumors, but its utility against tumor post-debulking is ineffective due to platelet cloaks that shield tumor cells from bioorthogonal pairing. We further discover tumor-infiltrating platelet levels respond to local pH changes. Elucidating this pH-platelet linkage, we design an injectable hydrogel for resection cavity implantation that simultaneously azido-tags tumor cells and inhibit their catalysis to acidify surrounding milieu. Unlike transient buffering, tumor acidification blockade sustains pH normalization, leading to durable platelet reduction. This reinstates bioorthogonal targeting of dibenzyl cyclooctyne-modified nanoparticles, thereby enhancing photodynamic ablation of residuals while amplifying systemic antitumor immunity. Concurrently, platelet/pH normalization interrupts metastasis cascade from invasion to circulation to colonization. Overall, attenuating tumor pH-platelet linkage unlocks bioorthogonal chemistry as a potential option for adjuvant therapy after tumor debulking.

The Dynamics of Platelet Content in Patients with Diffuse Peritonitis as a Predictor of Disease Outcome

BACKGROUND. Absolute numbers of platelets are of key importance for determining the severity of multiple organ failure in sepsis, while their fluctuations within normal values are not taken into account. At the same time, early detection of a downward trend in this parameter may have greater predictive value in predicting disease outcomes. AIM OF STUDY. To identify trends in changes in platelet levels in patients with widespread peritonitis and determine the possible relationship of these changes with the outcome of the disease. MATERIAL AND METHODS. The basis of the work was an analysis of the results of treatment of 220 patients with diffuse secondary peritonitis who were treated at the Elizavetinskaya Hospital in 2013–2019. A correlation analysis was conducted to identify relationships between disease outcomes, assessed according to the severity of postoperative complications, and the degree of platelet reduction, expressed in platelet ratio. The further ROC analysis allowed us to identify a threshold value of the platelet ratio, which excess indicated a high risk of an unfavorable outcome. RESULTS. Based on the data obtained, the threshold value of the platelet ratio in the first two days has no clinical significance. At the same time, starting from the third 3rd day of the postoperative period, the quality of the resulting classifier increased, which confirms the prognostic significance of the threshold value of the platelet ratio, which was 1.72 on the third 3rd day after surgery. In other words, a decrease in platelet levels more than 1.72-fold on the 3rd day indicates a high risk of an unfavorable outcome, which may be associated primarily with intra-abdominal complications. This provision also indirectly confirms the fact that among patients with platelet ratio (PR) values exceeding 1.72 on the 3rd day, 68.7 % ultimately underwent repeated surgical interventions (33 patients out of 48 with high PR values, and the overall mortality rate was 72.1 %.Similar indicators in the subgroup with low PR values were 27.6 % of reoperated patients (29 of 105) and 26.7 % of unfavorable outcomes. CONCLUSION. The results obtained indicate that the degree of platelet reduction, rather than their absolute levels, has greater predictive value in patients operated on for diffuse peritonitis.

Reduced Platelets Associated with All-Cause Mortality in the Pediatric Intensive Care Unit.

Platelets are crucial for maintaining physiological equilibrium, thrombosis formation, inflammation, bacterial defense, wound repair, angiogenesis, and tumorigenesis. In the Pediatric Intensive Care Unit (PICU), children frequently exhibit platelet reductions or functional alterations due to diverse pathological conditions, which significantly influence disease progression and therapeutic approaches. We analyzed the association between platelets count and its derived parameters and all-cause mortality. Adjusted smoothing spline plots, subgroup analysis and segmented multivariate logistic regression analysis were conducted to estimate the relative risk between proportional risk between platelets and all-cause mortality. Of the 11625 children, 677 (5.82%) died. After adjusting for confounders, there was a negative association between platelets and the risk of all-cause mortality in PICU. For every 100 × 10^9/L increase in platelets, the risk of death was reduced by 17% (adjusted OR = 0.83, 95% CI: 0.78, 0.89). The results of sensitivity analysis showed that in different stratified analyses (age, ICU category,WBC Count), the effect of platelets count on all-cause mortality remained stable. After adjusting for inflammation, nutrition, and liver function factors, platelets reduction is still an independent risk factor for PICU all-cause mortality.

Modulation of Staphylococcus aureus gene expression during proliferation in platelet concentrates with focus on virulence and platelet functionality.

Staphylococcus aureus is a well-documented bacterial contaminant in platelet concentrates (PCs), a blood component used to treat patients with platelet deficiencies. This bacterium can evade routine PC culture screening and cause septic transfusion reactions. Here, we investigated the gene expression modulation within the PC niche versus trypticase soy media (TSB) of S. aureus CBS2016-05, a strain isolated from a septic reaction, in comparison to PS/BAC/317/16/W, a strain identified during PC screening. RNA-seq analysis revealed upregulation of the capsule biosynthesis operon (capA-H), surface adhesion factors (sasADF), clumping factor A (clfA), protein A (spa), and anaerobic metabolism genes (pflAB, nrdDG) in CBS2016-05 when grown in PCs versus TSB, implying its enhanced pathogenicity in this milieu, in contrast to the PS/BAC/317/16/W strain. Furthermore, we investigated the impact of S. aureus CBS2016-05 on platelet functionality in spiked PCs versus non-spiked PC units. Flow cytometry analyses revealed a significant decrease in glycoprotein (GP) IIb (CD41) and GPIbα (CD42b) expression, alongside increased P-selectin (CD62P) and phosphatidylserine (annexin V) expression in spiked PCs compared to non-spiked PCs (p = 0.01). Moreover, spiked PCs exhibited a drastic reduction in MitoTrack Red FM and Calcein AM positive platelets (87.3% vs. 29.4%, p = 0.0001 and 95.4% vs. 24.7%, p = 0.0001) in a bacterial cell density manner. These results indicated that S. aureus CBS2016-05 triggers platelet activation and apoptosis, and compromises mitochondrial functionality and platelet viability, in contaminated PCs. Furthermore, this study enhanced our understanding of the effects of platelet-bacteria interactions in the unique PC niche, highlighting S. aureus increased pathogenicity and deleterious effect on platelet functionality in a strain specific manner. Our novel insights serve as a platform to improve PC transfusion safety.

Haematological Profile and Antibiotic Resistance of Bacteria Responsible for Enteric Infections Isolated From Patients Suffering From Malaria and Enteric Infections on Consultation at the Dschang Regional Hospital

Malarial and bacterial coinfections in low‐income countries are a serious cause of morbidity and mortality, necessitating coadministration of antibiotics and antimalarials. This study investigated the relationship between malaria infection and bacterial drug resistance in malaria and nonmalaria patients on consultation at the Dschang Regional Hospital. A follow‐up study was carried out from October 2020 to December 2021 on 127 malaria and 174 nonmalaria patients having enteric infections. Clinical and haematological parameters were measured using standard methods. CD4 and CD8 cells were determined using flow cytometry. Enteric bacteria pathogens were isolated from stool, and antimicrobial and antimalarial profiles were determined using agar diffusion and microdilution methods, respectively. Significant reduction of RBCs, WBCs, CD4, CD8, granulocytes, monocytes and platelets was seen in coinfected patients compared to monoinfected participants (p ≤ 0.0491). E. coli was the main pathogenic bacteria isolated from the digestive tract of coinfected patients (40.63%) and monoinfected patients (59.37%). E. coli showed a high level of resistance to AMX (57.69%) and CDA (61.54%) in coinfected patients compared to 55.26% and 41.67%, respectively, in monoinfected patients. Quinine (53[50.00%]; 6[42.86%]) presented a minimal inhibitory concentration (MIC) of 32 μg/mL on the bacteria isolates from coinfected and monoinfected patients, respectively, while Artemether 89 (83.96%), Maloxine 5 (3.94%) and Surquina 250 (39.37%) presented a MIC of 64 μg/mL on bacterial isolates of coinfected and monoinfected patients. E. coli showed high resistance against AKI (45.93%), AMX (43.75%) and ERY (59.37%) in malaria patients who were under antimalarial drugs compared to malaria patients who were not under malaria drugs (29.68%, 34.37% and 32.81%, respectively). This study highlights that antimalarial drugs might certainly have an influence on the acquisition and emergence of bacterial resistance in the case of malaria bacterial coinfection, and therefore, adequate management and planning effective control programmes might certainly go a long way to reduce the rate of morbidity and mortality.

Comprehensive Evaluation of Traditional Herbal Medicine Combined With Adjuvant Chemotherapy on Post-Surgical Gastric Cancer: A Systematic Review and Meta-Analysis.

Gastric cancer is a common cause of global mortality, with significant challenges during treatment due to side effects and complications. Traditional herbal medicine (THM) has emerged as a potential adjuvant therapy to enhance cancer treatment by reducing side effects and bolstering the immune response. This study conducted a meta-analysis to assess the efficacy and safety of THM as an adjuvant therapy in post-surgical gastric cancer patients. PubMed, Cochrane Library, EMBASE, CNKI, CiNii, KMBASE, KISS, OASIS, RISS, and ScienceON databases were searched from inception through December, 2021. The outcomes considered in this analysis encompassed tumor response, quality of life (QoL), side effects, and tumor markers. Additionally, a frequency analysis of the most commonly used herbs in the included studies was conducted. A total of 36 randomized controlled trials (RCTs) were included, and data were extracted according to study design. The analysis compared groups receiving chemotherapy alone with those receiving both chemotherapy and THM treatment. The group receiving both chemotherapy and THM showed substantial improvement in tumor response compared to the chemotherapy-only control group (RR 1.25, 95% CI [1.09, 1.45]). QoL also significantly increased in the THM-treated group. Most drug adverse reactions displayed statistical significance, except for platelet reduction. Tumor markers CEA, CA19-9, and CA72-4 exhibited significant improvements, but CA125 did not. The 1, 2, and 3-year survival rates improved, with RR values of 1.08 (95% CI [1.02, 1.14]), 1.32 (95% CI [1.19, 1.47]), and 1.42 (95% CI [1.12, 1.79]) respectively. However, some publication bias was indicated. THM may offer potential benefits as a complementary approach to post-surgical anticancer therapy in gastric cancer patients. Improved tumor response, quality of life, and survival rates were reported. However, it is important to exercise caution due to the possibility of publication bias, and further research is needed to confirm these findings.Registration:PROSPERO CRD 42022354133.

Abstract B179: 2-Deoxy-D-glucose (2-DG) combination with ketogenic diet induces sedation and hypothermia in mice that becomes lethal

Abstract Introduction. The term “ketogenic” was coined for the diet that specifically consists of a 4:1 ratio of fats to proteins. 2-Deoxy-d-glucose (2-DG) is a synthetic glucose analog that potently inhibits glycolysis. It has been hypothesized that 2-DG in combination with KD, should improve the anticancer effects of either therapeutic approach. The therapeutic benefit of such a combination was supported by studies of Voss et al. (Int J Mol Sci, 2018. 19(8): PMC6121440), showing that continued combination of KD and anti-glycolytic therapy is feasible, and KD increased tolerance to 2-DG. However, in contrast to this report, our preliminary studies revealed a dose-dependent reduction in the survival of mice of receiving inhibition of glycolysis (2-DG) and KD. The objective of this study was to assess the toxic limitation of the combination of glycolysis inhibition and ketogenic diet. Methods. CD-1 mice were maintained on either a standard diet (SD) or a ketogenic diet (KD). Some groups were treated with of 2-DG at 1.5 g/kg via the oral or intraperitoneal route or vehicle. For temperature monitoring, the animals were implanted subcutaneously with a temperature microchip UCT-2112. Body temperature was recorded manually for each mouse using a contactless, handheld URH-1HP receiver. Alternatively, for continuous monitoring of the body temperature, the UID Mouse Matrix was used. Mice exhibiting treatment-related toxicity symptoms, such as prolonged hypothermia or laborious breathing, and euthanized following blood collection for hematology and serum chemistry analysis. Key organs were also collected for histopathology analysis. Results. Previously, we reported that 2-DG reduces the survival of mice maintained on KD (median survival 9 days p=0.0022), while it is well tolerated by mice receiving regular chow (no deaths reported). Here, we report that the administration of 2-DG induces transient sedation and hypothermia. CBC analysis revealed that the number of platelets in the KD + 2-DG group was significantly decreased compared to the SD + 2-DG group and the KD + vehicle group (p&amp;lt;0.001). The reduction of platelets was associated with a two- to three-fold increase of LDH in the KD + 2-DG group. Histopathological analysis of the lung tissue revealed the presence of diffuse congestion in blood vessels and dilation of the alveolar capillaries consistent with interstitial pneumonia. Similarly, degenerative and congestive hepatic parenchyma was observed in animals treated with 2-DG and KD. Preliminary experiments involving supplementation of 2-DG-treated animals with D-glucose or D-mannose failed to provide a rescue effect. Conclusion. A highly reproducible, dose-dependent toxicity leading to rapid death of treated animals maintained on KD was observed following 2-DG administration, while the same doses appeared to be safe in mice fed a standard diet. The toxic effects induced by the combination treatment included acute thrombocytopenia and acute interstitial pneumonia; however, delineation of the exact mechanism of toxicity requires additional studies. Citation Format: Rafal Zielinski, Moises Martinez Castillo, Damian Grybowski, Krzysztof Grela, Roberto Cardenas-Zuniga, Izabela Fokt, Stanislaw Skora, Gerardo Ramirez, Waldemar Priebe. 2-Deoxy-D-glucose (2-DG) combination with ketogenic diet induces sedation and hypothermia in mice that becomes lethal [abstract]. In: Proceedings of the AACR-NCI-EORTC Virtual International Conference on Molecular Targets and Cancer Therapeutics; 2023 Oct 11-15; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2023;22(12 Suppl):Abstract nr B179.

Platelet Reduction after Aortic Bioprosthesis Implantation: Results from the PORTRAIT Study

Background: Platelet count reduction (PR) is a common but unclear phenomenon that occurs after aortic bioprosthesis valve implantation (bio-AVR). This study aimed to investigate the occurrence and clinical impact of PR in patients receiving stented, rapid deployment (RDV), or stentless bioprostheses. Methods: 1233 adult bio-AVR patients were enrolled. Platelet count variation, early post-operative adverse events, and in-hospital mortality were analysed. Results: 944 patients received a stented valve, an RDV was implanted in 218 patients, and 71 patients had a stentless bioprosthesis. In all groups, the platelet count at discharge was lower than the baseline values (p &lt; 0.001). The percentage of PR was 27% in the stented group, 56% in the RDV group, and 55% in the stentless group. A higher platelet reduction, reaching the minimum platelet value, was observed in the RDV (mean: −30.84, standard error (SE): 5.91, p &lt; 0.001) and stentless (mean: 22.54, SE: 9.10, p = 0.03) groups compared to the stented group. A greater PR occurred as the size of the bioprosthesis increased in RDV (p = 0.01), while platelet count variation was not directly proportional to the stented bioprosthesis size (p &lt; 0.001). PR was not affected by cardiopulmonary bypass (mean: −0.00, SE: 0.001, p = 0.635) or cross-clamp (mean: −0.00, SE: 0.002, p = 0.051) times in any of the groups. RDV subjects experienced more in-hospital adverse events. PR was found to be associated with ischemic strokes in the overall population. Conclusions: Bio-AVR is associated with significant but transient PR. RDV patients more likely experience significant PR and related adverse clinical events. PR is associated with ischemic strokes, regardless of the bioprosthesis type.

Safety and Tolerability of AZD0466 As Monotherapy for Patients with Advanced Hematologic Malignancies. Results from a Phase I/II Trial

Background: Overexpressionof B-cell lymphoma 2 (BCL-2)-related pro-survival proteins allows cancer cells to evade apoptosis, and targeting these proteins has become important in anticancer therapy. BCL-2 inhibition by venetoclax (VEN) is beneficial in many patients (pts) with acute myeloid leukemia (AML), but resistance is common due to upregulation of other pro-survival proteins such as BCL-extra-large (BCL-xL) and myeloid cell leukemia-1. Dual inhibition of BCL-2/xL has potential for broader activity than agents such as VEN. However, BCL-xL is critical for platelet survival and inhibition can cause dose-limiting thrombocytopenia (Konopleva and Letai. Blood 2018). To broaden therapeutic activity, we developed AZD0466, a drug-dendrimer conjugate in which the BCL-2/xL dual inhibitor AZD4320 is covalently conjugated to a pegylated poly-L-lysine dendrimer and gradually released by hydrolysis. Preclinically, AZD4320 showed greater inhibition of tumor growth than VEN and navitoclax in VEN-resistant xenograft models (Balachander et al. Clin Cancer Res 2020). A first-in-human study (NCT04214093) in pts with advanced solid tumors indicated that AZD0466 is well tolerated with no reported dose-limiting toxicities (DLTs). We present preliminary data from NIMBLE, a Phase I/II trial of AZD0466 in pts with advanced hematologic malignancies (NCT04865419). Methods: Module 1, Part A of NIMBLE is a dose-escalation study of AZD0466 monotherapy investigating its preliminary safety and tolerability, pharmacokinetics (PK), and preliminary efficacy. Dose escalation and de-escalation of AZD0466 follow a modified toxicity probability interval (mTPI-2) design. Eligible pts are ≥18 years old with relapsed/refractory (R/R) AML, acute lymphoblastic leukemia (ALL), or high-risk myelodysplastic syndrome. AZD0466 is administered IV with a dose ramp-up on Days (D) 1, 4, and 8, reaching the target dose on D8 of Cycle 1, with weekly administrations thereafter. Cycle duration is 35 days for Cycle 1 and 28 days for subsequent cycles. Pts remain on study until disease progression, unacceptable toxicity, or withdrawal of consent. Resul ts: As of May 31, 2023, 31 pts (n=25 AML, n=6 ALL; median age 69 years) had received ≥1 dose of AZD0466 at target doses of 300 mg (n=4), 600 mg (n=4), 1200 mg (n=7), 2400 mg (n=5), 3600 mg (n=9), and 5400 mg (n=2). Median treatment duration was 4.1 weeks (range 0.1−29.6). Twenty-two pts (71%) had prior VEN and 11 (35%) had prior hematopoietic stem cell transplantation. Treatment-emergent adverse events (TEAEs) of any grade reported in &amp;gt;10% of pts are displayed in Table 1. One Grade 5 intracranial hemorrhage unrelated to AZD0466 was reported. Four pts experienced a serious adverse event (SAE) possibly related to AZD0466 (alanine aminotransferase [ALT] increase, pneumonia, troponin T increase, and uncoded SAE). Grade ≥3 TEAEs possibly related to AZD0466, reported in 12 pts (39%), included febrile neutropenia (n=3), platelet count decrease (n=2), diarrhea, thrombocytopenia, ALT increase, blood creatinine phosphokinase increase, pneumonia, gamma-glutamyltransferase increase, lipase increased, and troponin T increase (n=1, each). DLTs of asymptomatic troponin increase were observed in two pts (3600 mg [n=1], 5400 mg [n=1]). Evaluation of maximum concentration and area under the concentration-time curve revealed dose-proportional exposure to AZD4320. Released AZD4320 represented 1-5% of total AZD4320 and had a longer half-life than total AZD4320. Preclinical modeling and PK data predicted that 5400 mg may be required to drive efficacy. As a surrogate of BCL-xL on-target activity, transient aggravation of thrombocytopenia post-dosing was observed across all dose cohorts followed by platelet recovery prior to the next dose. Platelet reduction was in line with preclinical models showing a substantial reduction at lower doses with a ceiling effect at higher doses. As of July 6, 2023, no complete responses have been observed. However, preliminary bone marrow (BM) blast reductions of &amp;gt;50% were observed in four pts (1200 mg [n=1], 2400 mg [n=2], 3600 mg [n=1]), indicating antileukemia activity of AZD0466. Conclusions: Given the observed DLTs of asymptomatic increase in troponin levels, and the lack of significant clinical benefit, the study was terminated.

Roginolisib a Highly Selective Allosteric Modulator of the Phosphoinositide 3-Kinase Delta (PI3Kδ) in Patients with Refractory/Relapsed Follicular Lymphoma

Introduction PI3Kδ inhibitors are active in patients (pts) with lymphomas, but their clinical development has been hampered by toxicity (Brown et al, Lancet Oncol 2022). Roginolisib (IOA-244) exerts an allosteric modulation of the PI3Kδ C-terminus and functions as a non-ATP competitive PI3Kδ inhibitor, delivering a selective inhibition without off-target effects typically seen with other PI3K inhibitors (Johnson et al, Cancer Res Commun 2023). Using the recommended phase 2 dose (RP2D) of 80 mg QD established in solid tumors patients, patients with refractory/relapsed (r/r) follicular lymphoma (FL) were treated to investigate its safety profile in pts with hematologic malignancies (NCT04328844). Methods In Part A of the FiH dose escalation study, roginolisib was investigated at 20 and 80 mg QD in pts with r/r FL. Primary objective: safety of the RP2D established in solid tumor pts. Secondary objectives: PK; PD (e.g., changes in immune cell subsets in peripheral blood); Lugano-based responses; PFS and OS. Results In Part A for pts with r/r FL, there were two cohorts: (a) Cohort 1: 20 mg QD daily (4/4; 2 female, 2 male); (b) Cohort 2: 80 mg QD (4/4; 3 female, 1 male). There were no DLT observed and no dose modifications were needed. The mean time on treatment was 1.9 months (20 mg QD) and 4.3 months (80 mg QD), with one patient at the 80 mg receiving Roginolisib for 9 mo. More than 4 prior lines of treatment were in 3/8 pts. Transient (lasting less than 48 hrs) platelet reduction (G3) and AST/ALT elevation (G3) were observed in 2/8 pts, which improved while pts continued without a treatment intervention, such as dose modification or medical treatment with steroids. Lugano-based PRs were observed in 2/4 pts at the 80 mg QD dose and none at the 20 mg QD. At the 80 mg QD dose a third pt had a clinical response manifested by improvement in night sweats and fever, reduction in cervical palpable lymph nodes and relief from chronic pleural effusion. This clinical improvement lasted less than 5 weeks. While Overall Survival (OS) is still ongoing, the median has not been reached in this study and is currently at 14.3 mo. Subsequent to ending Roginolisib treatment, patients received at least one additional therapy (6/8), one patient was able to undergo autologous transplant with a complete metabolic response (CMR). Biomarker evaluation using flow cytometry showed low counts of T regulatory cells (Treg) in peripheral blood in all 8 r/r FL patients compared to solid tumor patients at baseline and throughout the treatment. Myeloid derived suppressor cells in peripheral blood remained unchanged during the course of treatment with Roginolisib. Conclusions The safety profile of roginolisib in pts with r/r FL appears to match that in pts with solid malignancies. In contrast to other PI3Kδ inhibitors, roginolisib is highly selective for binding to PI3Kδ, favoring an inactive confirmation of PI3Kd and functions as a non-ATP competitive inhibitor.

CHARACTERIZING CELLULAR COMPONENTS OF BONE MARROW ASPIRATE CONCENTRATE: A ONE-STEP CELL THERAPY FOR ANKLE CARTILAGE DEFECTS

AbstractObjectivesBone marrow aspirate concentrate (BMAC), together with fibrin glue (Tisseel, Baxter, UK) and Hyaluronic acid (HA) were used as a one-step cell therapy treating patients with ankle cartilage defects in our hospital. This therapy was proven to be safe, with patients demonstrating a significant improvement 12 months post-treatment. Enriched mesenchymal stem cells (MSCs) in BMAC are suggested inducers of cartilage regeneration, however, currently there is no point-of-care assessment for BMAC quality; especially regarding the proportion of MSCs within. This study aims to characterise the cellular component of CCR-generated BMAC using a point-of-care device, and to investigate if the total nucleated cell (TNC) count and patient age are predictive of MSC concentration.MethodsDuring surgery, 35ml of bone marrow aspirate (BMA) was collected from each patients’ iliac crest under anaesthesia, and BMAC was obtained via a commercial kit (Cartilage Regeneration kit, CCR, Innotec®, UK). BMAC was then mixed with thrombin (B+T) for injection with HA and fibrinogen. In our study, donor-matched BMA, BMAC and B+T were obtained from consented patients (n=12, age 41 ± 16years) undergoing surgery with BMAC therapy. TNC, red blood cell (RBC) and platelet (PLT) counts were measured via a haematology analyser (ABX Micros ES 60, Horiba, UK), and the proportion of MSCs in BMA, BMAC and B+T were assessed via colony forming unit-fibroblast (CFU-F) assays. Significant differences data in matched donors were tested using Friedman test. All data were shown as mean ± SD.ResultsMean TNC counts in BMA and BMAC were not significantly different (14.0 ± 4.4 million/ml and 19.4 ± 32.9 million/ml, respectively, P&gt;0.9999). However, TNC counts were significantly lower in B+T compared to BMAC (9.7 ± 24.5 million/ml and 19.4 ± 32.9 million/ml, respectively, P=0.0167). Similarly, PLT counts were decreased in B+T compared to BMAC (40.7 ± 30.7 million/ml and 417.5 ± 365.5 million/ml, respectively, P&lt;0.0001), however, PLTs were significantly concentrated in BMAC compared to BMA (417.5 ± 365.5 million/ml and 114.8 ± 61.6 million/ml, respectively, P=0.0429). RBC counts were significantly decreased in BMAC and B+T compared to BMA (P=0.0322 and P&lt;0.0001, respectively). Higher concentration of MSCs were observed in BMAC compared to BMA (0.006% ± 0.01% and 0.00007% ± 0.0001%, respectively, P=0.0176). Similar to TNCs and PLTs, the proportion of MSCs significantly decreased in B+T compared to BMAC (0.0004% ± 0.001% and 0.006% ± 0.01%, respectively, P=0.0023). Furthermore, patient age and TNC counts did not correlate with MSC concentration (Spearman's Rank test, P=0.3266 and P=0.4880, respectively).ConclusionsBMAC successfully concentrated PLTs, but BMAC preparations were highly variable. Mixing BMAC and thrombin however, as described in the CCR protocol, resulted in a dramatic reduction in TNCs, PLTs and MSCs. TNC counts and patient age could not be used to predict the MSC proportion in the BMAC based on current data. Future work aims to look at the biomolecule profile of BMAC plasma, and to correlate them to patient clinical outcomes.Declaration of Interest(a) fully declare any financial or other potential conflict of interest

Improving the chances of response to splenectomy in immune thrombocytopenia.

Immune thrombocytopenia (ITP) is an autoimmune bleeding disorder characterized by isolated thrombocytopenia. Its pathogenesis is complex relying in large part on destruction of platelets recognized by autoantibodies within the spleen. However, other mechanisms, such as platelet desialylation, may play a role in platelet reduction by accelerating their clearance in the liver. In their study, Mendoza and colleagues reported on platelet scintigraphy performed in 51 ITP patients, showing a response in 87.5% when the sequestration occurred in the spleen versus 45% in case of non-splenic destruction. Platelet desialylation was also measured after splenectomy and found to be higher in non-responder patients. These latter results, while requiring confirmation prior to splenectomy, support platelet desialylation may also be a potential biomarker of non-response to splenectomy. Commentary on: Mendoza etal. Study of platelet kinetics in immune thrombocytopenia to predict splenectomy response. Br J Haematol 2024;204:315-323.

Alterations in the von Willebrand factor/ADAMTS-13 axis in preeclampsia

BackgroundPreeclampsia is a gestational hypertensive disorder characterized by maternal endothelial activation and increased ratio of soluble fms-like tyrosine kinase-1 (sFlt-1) inhibitor to placental growth factor (PlGF). The von Willebrand factor (VWF)/ADAMTS-13 axis is of interest because of the underlying endothelial activation and clinical overlap with pregnancy-associated thrombotic thrombocytopenic purpura. ObjectivesTo assess VWF, ADAMTS-13, and VWF/ADAMTS-13 ratio in preeclampsia and look for associations with sFlt-1/PlGF ratio and clinical features. MethodsThirty-four preeclampsia cases and 48 normal pregnancies were assessed in a case-control study. Twelve normal pregnancies in women with a history of preeclampsia formed an additional comparator group. VWF antigen (VWF:Ag) and VWF activity (VWF:Ac [VWF:glycoprotein IbM]) were measured via automated immunoturbidimetric assay, ADAMTS-13 activity was measured via fluorescence resonance energy transfer–VWF73 assay, and sFlt-1 and PlGF were measured via enzyme-linked immunosorbent assay. ResultsVWF:Ag was higher in preeclampsia than in normal pregnancy (median, 3.07 vs 1.87 IU/mL; P < .0001). ADAMTS-13 activity was slightly lower (median, 89.6 vs 94.4 IU/dL; P = .02), with no severe deficiencies. Significant elevations in VWF:Ac were not observed in preeclampsia, resulting in reduced VWF:Ac/VWF:Ag ratios (median, 0.77 vs 0.97; P < .0001). VWF:Ag/ADAMTS-13 ratios were significantly higher in preeclampsia (median, 3.42 vs 2.06; P < .0001), with an adjusted odds ratio of 19.2 for a ratio of >2.7 (>75th centile of normal pregnancy). Those with a history of preeclampsia had similar ratios to normal pregnant controls. VWF:Ag/ADAMTS-13 and sFlt-1/PlGF were not correlated. However, percentage reduction in platelets correlated positively with VWF:Ac (P = .01), VWF:Ac/VWF:Ag ratio (P = .004), and sFlt-1/PlGF ratio (P = .01). ConclusionThe VWF/ADAMTS-13 axis is significantly altered in preeclampsia. Further investigation of potential clinical utility is warranted.

Clinical profiles and predictors of survival in severe dengue cases.

Dengue is endemic in tropical countries. Severe dengue has a high risk of morbidity and mortality. We aimed to identify factors associated with dengue survival among our intensive care unit (ICU) patients. A retrospective study was conducted among dengue cases admitted to the ICU of Hospital Sultan Abdul Halim, Kedah, Malaysia from 2016 to 2019. Out of 1,852 dengue cases admitted to the hospital, 7.2% of patients required ICU admission. Survival rate was 88.6% among severe dengue cases. The majority of severe dengue patients were obese, while other notable comorbidities included hypertension and diabetes mellitus. Also, 73% of patients presented in the critical phase, at a median of Day 4 of illness. All patients admitted to the ICU had a history of fever. The predominant warning signs were lethargy, fluid accumulation and haemoconcentration with rapid platelet reduction. Among nonsurvivors, 69.2% had fulminant hepatitis, 53.8% had massive bleeding or disseminated intravascular coagulation, 38.5% had haemophagocytic lymphohistiocytosis and 30.8% had myocarditis. The predominant serotypes were DENV-3 and DENV-1. The least number of cases was seen in 2017, when all serotypes were equally presented. Multiple logistic regression showed that Sequential Organ Failure Assessment (SOFA) score, peak international normalised ratio, peak partial thromboplastin time and aspartate aminotransferase on admission were independent risk factors for survival. This model had an area under the curve of 0.98, giving an overall 98.2% accuracy. Specific warning signs and blood investigations in dengue patients may aid in early decision for ICU admission. Monitoring of SOFA scores plus coagulation and liver enzyme profiles could improve dengue survival rates.