Hematopoietic stem cell collection for sickle cell disease gene therapy

PURPOSE OF REVIEW

Gene therapy for sickle cell disease (SCD) is advancing rapidly, with two transformative products recently approved by the US Food and Drug Administration and numerous others under study. All current gene therapy protocols require ex vivo modification of autologous hematopoietic stem cells (HSCs). However, several SCD-related problems impair HSC collection, including a stressed and damaged bone marrow, potential cytotoxicity by the major therapeutic drug hydroxyurea, and inability to use granulocyte colony stimulating factor, which can precipitate severe vaso-occlusive events.

RECENT FINDINGS

Peripheral blood mobilization of HSCs using the CXCR4 antagonist plerixafor followed by apheresis collection was recently shown to be safe and effective for most SCD patients and is the current strategy for mobilizing HSCs. However, exceptionally large numbers of HSCs are required to manufacture an adequate cellular product, responses to plerixafor are variable, and most patients require multiple mobilization cycles, increasing the risk for adverse events. For some, gene therapy is prohibited by the failure to obtain adequate numbers of HSCs.

SUMMARY

Here we review the current knowledge on HSC collection from individuals with SCD and potential improvements that may enhance the safety, efficacy, and availability of gene therapy for this disorder.

A review on potential heterocycles for the treatment of glioblastoma targeting receptor tyrosine kinases

Glioblastoma, the most aggressive form of brain tumor, poses significant challenges in terms of treatment success and patient survival. Current treatment modalities for glioblastoma include radiation therapy, surgical intervention, and chemotherapy. Unfortunately, the median survival rate remains dishearteningly low at 12-15 months. One of the major obstacles in treating glioblastoma is the recurrence of tumors, making chemotherapy the primary approach for secondary glioma patients. However, the efficacy of drugs is hampered by the presence of the blood-brain barrier and multidrug resistance mechanisms. Consequently, considerable research efforts have been directed toward understanding the underlying signaling pathways involved in glioma and developing targeted drugs. To tackle glioma, numerous studies have examined kinase-downstream signaling pathways such as RAS-RAF-MEK-ERK-MPAK. By targeting specific signaling pathways, heterocyclic compounds have demonstrated efficacy in glioma therapeutics. Additionally, key kinases including phosphatidylinositol 3-kinase (PI3K), serine/threonine kinase, cytoplasmic tyrosine kinase (CTK), receptor tyrosine kinase (RTK) and lipid kinase (LK) have been considered for investigation. These pathways play crucial roles in drug effectiveness in glioma treatment. Heterocyclic compounds, encompassing pyrimidine, thiazole, quinazoline, imidazole, indole, acridone, triazine, and other derivatives, have shown promising results in targeting these pathways. As part of this review, we propose exploring novel structures with low toxicity and high potency for glioma treatment. The development of these compounds should strive to overcome multidrug resistance mechanisms and efficiently penetrate the blood-brain barrier. By optimizing the chemical properties and designing compounds with enhanced drug-like characteristics, we can maximize their therapeutic value and minimize adverse effects. Considering the complex nature of glioblastoma, these novel structures should be rigorously tested and evaluated for their efficacy and safety profiles.

TYK2 inhibition with deucravacitinib ameliorates erosive oral lichen planus

Erosive oral lichen planus (OLP) is a challenging disease. This T cell driven disorder frequently shows a treatment unresponsive course and strongly limits patients' quality of life. The disease lacks FDA or EMA approved drugs for its treatment and the efficacy of the commonly administered treatments (i.e. topical and systemic steroids, steroid sparing agents) is often only partial. Although the etiopathogenesis of the disease still needs to be fully elucidated, recent advances helped to identify interferon-ɣ (IFN-ɣ) as a pivotal cytokine in OLP pathogenesis, thus making the interference with its signalling a therapeutic target. Janus kinase (JAK) inhibitors therefore gained relevance for their inhibitory effect on IFN-ɣ signalling. While some drugs such as abrocitinib, upadacitinib, tofacitinib directly interfere with IFN-ɣ signalling through blockade of JAK1 and/or JAK2, deucravacitinib, a selective TYK-2 inhibitor indirectly interferes on IFN-ɣ activation through interference with interleukin (IL)-12, a potent promotor for Th1/IFN-ɣ responses. This mechanism of action makes deucravacitinib a candidate drug for the treatment of OLP. Here we provide initial evidence that deucravacitinib 6 mg daily has a beneficial effect in three patients with oral OLP.

Impact of plerixafor use in the mobilization of blood grafts for autologous hematopoietic cell transplantation

Plerixafor (PLER), a reversible antagonist of the CXC chemokine receptor type 4, has been in clinical use for mobilization of blood grafts for autologous hematopoietic cell transplantation (AHCT) for about 15 years. Initially PLER was investigated in placebo-controlled trials with the granulocyte colony-stimulating factor (G-CSF) filgrastim. It has also been used in combination with chemotherapy plus G-CSF in patients who had failed a previous mobilization attempt or appeared to mobilize poorly with current mobilization (preemptive use). This review summarizes what is known regarding addition of PLER to standard mobilization regimens. PLER increases mobilization of CD34+ cells, decreases the number of apheresis sessions needed to achieve collection targets and increases the proportion of patients who can proceed to AHCT. It appears also to increase the amount of various lymphocyte subsets in the grafts collected. In general, hematologic recovery after AHCT has been comparable to patients mobilized without PLER, although slower platelet recovery has been observed in some studies of patients who mobilize poorly. In phase III studies, long-term outcome has been comparable to patients mobilized without PLER. This also appears to be the case in patients receiving plerixafor for poor or suboptimal mobilization of CD34+ cells. In practice, PLER is safe and has not been shown to increase tumor cell mobilization.

Deucravacitinib, a selective, allosteric tyrosine kinase 2 inhibitor, in scalp psoriasis: A subset analysis of two phase 3 randomized trials in plaque psoriasis

BACKGROUND

Scalp involvement in plaque psoriasis is challenging to treat.

OBJECTIVE

To evaluate the efficacy and safety of deucravacitinib (DEUC) in scalp psoriasis.

METHODS

POETYK PSO-1 and PSO-2 were global phase 3, 52-week, double-blinded trials in adults with moderate to severe psoriasis. Patients were randomized 1:2:1 to oral placebo, DEUC 6 mg once daily, or apremilast 30 mg twice daily. This pooled secondary analysis evaluated scalp-specific Physician Global Assessment score of 0 or 1 (0/1), ≥90% improvement from baseline in Psoriasis Scalp Severity Index, and change from baseline in Psoriasis Scalp Severity Index. Adverse events were evaluated through week 16.

RESULTS

Overall, 1084 patients with moderate to severe scalp psoriasis at baseline were included. At week 16, response rates were greater with DEUC versus placebo or apremilast for scalp-specific Physician Global Assessment 0/1 (64.0% vs 17.3% vs 37.7%; P < .0001), ≥90% improvement from baseline in Psoriasis Scalp Severity Index (50.6% vs 10.5% vs 26.1%; P < .0001), and change from baseline in Psoriasis Scalp Severity Index. Responses were maintained through 52 weeks with continuous DEUC. Safety was consistent with the entire study population.

LIMITATIONS

Lack of data in milder scalp psoriasis.

CONCLUSION

DEUC was significantly more efficacious than placebo or apremilast in improving moderate to severe scalp psoriasis and was well tolerated.

Effect of voxelotor on murine bone marrow and peripheral blood with hematopoietic progenitor cell mobilization for gene therapy of sickle cell disease

In preparation for hematopoietic stem cell mobilization and collection, current ex vivo gene therapy protocols for sickle cell disease require patients to undergo several months of chronic red cell transfusion. For health care equity, alternatives to red cell transfusion should be available. We examined whether treatment with GBT1118, the murine analog of voxelotor, could be a safe and feasible alternative to red cell transfusion. We found that 3 weeks of treatment with GBT1118 increased the percentage of bone marrow hematopoietic stem cells and upon plerixafor mobilization, the percentage of peripheral blood hematopoietic stem cells. Our data suggest that voxelotor should be further explored for its potential safety and utility as preparation for hematopoietic stem cell mobilization and collection.

Recent drug design strategies and identification of key heterocyclic scaffolds for promising anticancer targets

Cancer, a noncommunicable disease, is the leading cause of mortality worldwide and is anticipated to rise by 75% in the next two decades, reaching approximately 25 million cases. Traditional cancer treatments, such as radiotherapy and surgery, have shown limited success in reducing cancer incidence. As a result, the focus of cancer chemotherapy has switched to the development of novel small molecule antitumor agents as an alternate strategy for combating and managing cancer rates. Heterocyclic compounds are such agents that bind to specific residues in target proteins, inhibiting their function and potentially providing cancer treatment. This review focuses on privileged heterocyclic pharmacophores with potent activity against carbonic anhydrases and kinases, which are important anticancer targets. Evaluation of ongoing pre-clinical and clinical research of heterocyclic compounds with potential therapeutic value against a variety of malignancies as well as the provision of a concise summary of the role of heterocyclic scaffolds in various chemotherapy protocols have also been discussed. The main objective of the article is to highlight key heterocyclic scaffolds involved in recent anticancer drug design that demands further attention from the drug development community to find more effective and safer targeted small-molecule anticancer agents.

Baseline inflammation indexes and neutrophil-to-LDH ratio for prediction of the first mobilization failure without plerixafor-based regimens in multiple myeloma and lymphoma patients: A single-center retrospective study

BACKGROUND

Many factors were identified for mobilization failure (MF) in autologous hematopoietic stem-cell transplantation. To our knowledge, this is the first study to investigate the efficacy of baseline inflammation indexes and neutrophil-to-lactate dehydrogenase (LDH) ratio to predict MF in multiple myeloma (MM) and lymphoma.

METHODS

A total of 240 patients with lymphoma or MM hospitalized between January 2014 and June 2022 for the first stem cell mobilization were included in this retrospective single-center study. We evaluated the impact of baseline demographic, clinical, and laboratory data (before granulocyte colony-stimulating factor and chemotherapy implementation), including neutrophil, neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio, monocyte-to-lymphocyte ratio, systemic immune-inflammation index (SII), systemic inflammatory response index (SIRI), neutrophil-to-C-reactive protein, and neutrophil-to-LDH ratios on MF.

RESULTS

A total of 240 patients were divided into successful (214 patients, 89.16%) and poor mobilizers (26 patients, 10.84%). Poor mobilizers had lower neutrophil, NLR, SII, and neutrophil-to-LDH ratios (P values were .001, .022, .001, and .001, respectively). Among these markers, only the neutrophil-to-LDH ratio was statistically low in both poor mobilizer MM and lymphoma patients. Receiving operator characteristic curve analysis was performed to evaluate neutrophil, SII, and neutrophil-to-LDH ratios for MF. Neutrophil-to-LDH ratio had the highest specificity (93.93%, for ≤9.904 cut-off) compared to the other two variables. Multivariate logistic regression analysis showed that neutrophil-to-LDH ratio ≤ 9.904 (cut-off) (odds ratio: 7.116, P = .001), neutrophil counts ≤3300/mm3 (cut-off) (odds ratio: 3.248, P = .021), and lymphoma diagnosis (odds ratio: 2.674, P = .039) were independent risks for MF.

CONCLUSION

The neutrophil-to-LDH ratio could be a novel marker in lymphoma and MM patients to predict the first MF. New studies should be conducted for the optimization of this index.

Stem Cells mobilization and collection in allogeneic related and unrelated donors: a single center experience with focus on plerixafor

INTRODUCTION

Poor CD34 + cells mobilization in allogeneic donors could affect transplant outcome. In a subgroup of patient mobilization with granulocyte colony-stimulating factor (G-CSF) alone is unsatisfactory, and Plerixafor could be used to enhance CD34 + cells release from bone marrow niche.

MATERIALS AND METHODS

We conducted a retrospective single-center, cohort study on healthy allogeneic donors both related and unrelated, treated by Udine Transfusion Center over the last 10 years (2012-2022). In the 195 allogeneic donors treated we analyzed age, sex, body weight, BMI, comorbidities, G-CSF dosage and even baseline white blood cell count as possible predictor of insufficient CD34 + cells mobilization on day 5. In the subgroup of related donors we evaluated even baseline CD34 + cells (measured before mobilization start). Processed donor blood volume, collection efficiency and apheresis product were examined. Additionally a comparative analysis was conducted between G-CSF alone treated donors and poor mobilizing ones, in which Plerixafor was administered at a dose of 0.24 mg/kg as a pre-emptive or rescue agent.

RESULTS

In 9 donors, due to poor mobilization (defined as CD34 + < 20/µL or estimated yield < 1 ×106 kg/recipient body weight), the use of plerixafor was necessary. PLX at a dose of 0.24 mg/kg was administered 5 h before collection, inducing an average increase of 5.1 (1.7-12.6) in CD34 + circulating cells. In this subgroup of patients, BMI and weight were significantly lower (p = 0.03). Interestingly, baseline CD34 + cells (measured before the onset of mobilization) also seems to predict poor mobilization (p = 0.003). In donors additionally treated with Plerixafor compared to those who received G-CSF alone, collection efficiency was higher (p = 0.02) and CD34 + cells collected were comparable (p = 0.2). Side effects related to the administration of plerixafor, if they occurred, were well tolerated.

CONCLUSIONS

Plerixafor is a safe and effective drug in the rescue and prevention of poor mobilization. New prospective studies on allogeneic donors should be performed to increase the treatable population to avoid inadequate collection and mobilization. New laboratory predictors such as baseline CD34 + cells should be investigated in larger cohorts and then used as early screening.

Plerixafor in autologous stem cell transplantation: Does it affect engraftment kinetics?

Plerixafor increases stem cell mobilization by reversibly binding to the chemokine receptor CXCR4. In our study, we examined the results of mobilization with plerixafor and granulocyte colony-stimulating factor (G-CSF) and revealed their effects on autologous stem cell transplantation (ASCT) engraftment kinetics. The study included all cases of ASCT performed in the Adult Bone Marrow Transplantation Unit of xxx University between January 2014 and January 2022. It included a total of 300 patients. The total number of CD34 + cells collected was 7.44 ± 4.19 in patients with plerixafor and 9.53 ± 6.09 in patients without plerixafor. The mean neutrophil and platelet engraftment took longer in plerixafor-mobilized patients (neutrophil: 12 ± 4.1 vs. 10.2 ± 2.7 days; platelet: 21.6 ± 13.9 vs. 14.2 ± 5.9 days; p = 0.008 and p = 0.002). The number of febrile neutropenia attacks was significantly higher in plerixafor-mobilized patients (p = 0.04). In the chemo-mobilized patient subgroup, plerixafor-mobilized patients experienced more febrile neutropenia attacks (p = 0.04). The mean time to both neutrophil and platelet engraftment was longer in patients mobilized with plerixafor. In the subgroup of patients with MM, the mean time to platelet engraftment was longer in patients mobilized with plerixafor. Plerixafor and its effect on engraftment kinetics should be evaluated with further studies in a larger population with survival analysis.

Stem cell collection after lenalidomide, bortezomib and dexamethasone plus elotuzumab or isatuximab in newly diagnosed multiple myeloma patients: a single centre experience from the GMMG-HD6 and -HD7 trials

BACKGROUND

While quadruplet induction therapies deepen responses in newly diagnosed multiple myeloma patients, their impact on peripheral blood stem cell (PBSC) collection remains incompletely understood. This analysis aims to evaluate the effects of prolonged lenalidomide induction and isatuximab- or elotuzumab-containing quadruplet induction therapies on PBSC mobilization and collection.

METHODS

A total of 179 transplant-eligible patients with newly diagnosed MM treated at a single academic center were included. The patients were evaluated based on PBSC mobilization and collection parameters, including overall collection results, CD34+ cell levels in peripheral blood, leukapheresis (LP) delays, overall number of LP sessions, and the rate of rescue mobilization with plerixafor. The patients underwent four different induction regimens: Lenalidomide, bortezomib, and dexamethasone (RVd, six 21-day cycles, n = 44), isatuximab-RVd (six 21-day cycles, n = 35), RVd (four 21-day cycles, n = 51), or elotuzumab-RVd (four 21-day cycles, n = 49).

RESULTS

The patients' characteristics were well balanced across the different groups. Collection failures, defined as the inability to collect three sufficient PBSC transplants, were rare (n = 3, 2%), with no occurrences in the isatuximab-RVd and elotuzumab-RVd groups. Intensified induction with six 21-day cycles of RVd did not negatively impact the overall number of collected PBSCs (9.7 × 106/kg bw versus 10.5 × 106/kg bw, p = 0.331) compared to four 21-day cycles of RVd. Plerixafor usage was more common after six cycles of RVd compared to four cycles (16% versus 8%). Addition of elotuzumab to RVd did not adversely affect overall PBSC collection (10.9 × 106/kg bw versus 10.5 × 106/kg bw, p = 0.915). Patients treated with isatuximab-RVd (six cycles) had lower numbers of collected stem cells compared to those receiving RVd (six cycles) induction (8.8 × 106/kg bw versus 9.7 × 106/kg bw, p = 0.801), without experiencing significant delays in LP or increased numbers of LP sessions in a multivariable logistic regression analysis. Plerixafor usage was more common after isatuximab plus RVd compared to RVd alone (34% versus 16%).

CONCLUSIONS

This study demonstrates that stem cell collection is feasible after prolonged induction with isatuximab-RVd without collection failures and might be further explored as induction therapy.

TRIAL REGISTRATION

Patients were treated within the randomized phase III clinical trials GMMG-HD6 (NCT02495922, 24/06/2015) and GMMG-HD7 (NCT03617731, 24/07/2018). However, during stem cell mobilization and -collection, no study-specific therapeutic intervention was performed.

Steady-state versus chemotherapy-based hematopoietic cell mobilization after anti-CD38-based induction therapy in newly diagnosed multiple myeloma

BACKGROUND

The incorporation of anti-CD38 monoclonal antibodies (mAb) in induction regimens of newly diagnosed transplant-eligible multiple myeloma (MM) patients has been established as a new standard. However, the optimal strategy of stem cell mobilization in this context is not yet clear.

STUDY DESIGN AND METHODS

From May 2020 till September 2022, we retrospectively reviewed patients receiving anti-CD38 mAb-based induction therapy followed by stem cell mobilization either in a steady-state protocol (SSM) using 10 μg/kg granulocyte colony-stimulating factor (G-CSF) for 5 days or in a chemotherapy-based protocol (CM) using 1-4 g/m2 cyclophosphamide and G-CSF.

RESULTS

Overall, 85 patients (median age 61 years) were included in the analysis. In total, 90 mobilization attempts were performed, 42 with SSM and 48 with CM. There was no significant difference in the median concentration of CD34+ cells in peripheral blood (PB) prior to apheresis between SSM and CM (61/μL vs. 55.4/μL; p = .60). Cumulative CD34+ yields did not differ between the groups with median of 6.68 and 6.75 × 106 /kg body weight, respectively (p = .35). The target yield (≥4 × 106 CD34+ cells/kg body weight) was reached in 88% (CM) and 86% (SSM), with a high proportion even after a single apheresis session (76% vs. 75%). Plerixafor was found to be more frequently used in SSM (52%) than in CM (23%; p < .01). A total of 83 patients underwent autologous transplantation and all were engrafted.

CONCLUSIONS

Stem cell collection in patients undergoing anti-CD38-based induction therapy is feasible with either CM or SSM, although SSM more frequently requires plerixafor.

GPC-100, a novel CXCR4 antagonist, improves in vivo hematopoietic cell mobilization when combined with propranolol

Autologous Stem Cell Transplant (ASCT) is increasingly used to treat hematological malignancies. A key requisite for ASCT is mobilization of hematopoietic stem cells into peripheral blood, where they are collected by apheresis and stored for later transplantation. However, success is often hindered by poor mobilization due to factors including prior treatments. The combination of G-CSF and GPC-100, a small molecule antagonist of CXCR4, showed potential in a multiple myeloma clinical trial for sufficient and rapid collection of CD34+ stem cells, compared to the historical results from the standards of care, G-CSF alone or G-CSF with plerixafor, also a CXCR4 antagonist. In the present study, we show that GPC-100 has high affinity towards the chemokine receptor CXCR4, and it potently inhibits β-arrestin recruitment, calcium flux and cell migration mediated by its ligand CXCL12. Proximity Ligation Assay revealed that in native cell systems with endogenous receptor expression, CXCR4 co-localizes with the beta-2 adrenergic receptor (β2AR). Co-treatment with CXCL12 and the β2AR agonist epinephrine synergistically increases β-arrestin recruitment to CXCR4 and calcium flux. This increase is blocked by the co-treatment with GPC-100 and propranolol, a non-selective beta-adrenergic blocker, indicating a functional synergy. In mice, GPC-100 mobilized more white blood cells into peripheral blood compared to plerixafor. GPC-100 induced mobilization was further amplified by propranolol pretreatment and was comparable to mobilization by G-CSF. Addition of propranolol to the G-CSF and GPC-100 combination resulted in greater stem cell mobilization than the G-CSF and plerixafor combination. Together, our studies suggest that the combination of GPC-100 and propranolol is a novel strategy for stem cell mobilization and support the current clinical trial in multiple myeloma registered as NCT05561751 at www.clinicaltrials.gov.

[Comparison of Plerixafor or Cyclophosphamide Combined with G-CSF in Mobilization of Peripheral Blood Stem Cells in Multiple Myeloma]

OBJECTIVE

To compare the efficacy of plerixafor (PXF) combined with granulocyte colony-stimulating factor (G-CSF) (PXF+G-CSF) and cyclophosphamide (Cy) combined with G-CSF (Cy+G-CSF) in the mobilization of peripheral blood stem cells (PBSCs) in patients with multiple myeloma (MM).

METHODS

The clinical data of 41 MM patients who underwent PBSC mobilization using PXF+G-CSF (18 cases) or Cy+G-CSF (23 cases) in Shanxi Bethune Hospital from January 2019 to December 2021 were retrospectively analyzed, including the count of collected CD34+ cells, acquisition success rate, failure rate, and optimal rate. The correlation of sex, age, disease type, DS staging, ISS staging, number of chemotherapy cycle, disease status before mobilization, and mobilization regimen with the collection results was analyzed, and the adverse reactions, length of hospital stay, and hospitalization costs were compared between the two mobilization regimens.

RESULTS

The 41 patients underwent 97 mobilization collections, and the median number of CD34+ cells collected was 6.09 (0-34.07)×106/kg. The acquisition success rate, optimal rate, and failure rate was 90.2%, 56.1%, and 9.8%, respectively. Univariate analysis showed that sex, age, disease type, and disease stage had no significant correlation with the number of CD34+ cells collected and acquisition success rate (P >0.05), but the patients with better disease remission than partial remission before mobilization were more likely to obtain higher CD34+ cell count (P <0.05). The PXF+G-CSF group had a larger number of CD34+ cells and higher acquisition success rate in the first collection than Cy+G-CSF group (both P <0.05), and had lower infection risk and shorter length of hospital stay during mobilization (both P <0.05), but the economic burden increased (P <0.05).

CONCLUSION

PXF+G-CSF used for PBSC mobilization in MM patients has high first acquisition success rate, large number of CD34+ cells, less number of collection times, and short length of hospital stay, but the economic cost is heavy.

[Efficacy and Safety of Plerixafor Combined with G-CSF for Autologous Peripheral Blood Hematopoietic Stem Cell Mobilization in Lymphoma Patients]

OBJECTIVE

To investigate the efficacy and safety of plerixafor combined with granulocyte colony-stimulating factor (G-CSF) in mobilizing peripheral blood hematopoietic stem cells in patients with lymphoma.

METHODS

The clinical data of lymphoma patients who received autologous hematopoietic stem cell mobilization using plerixafor combined with G-CSF from January 2019 to December 2021 were retrospectively analyzed. The patients received 3 kinds of mobilization regimens: front-line steady-state mobilization, preemptive intervention, and recuse mobilization. The acquisition success rate, excellent rate of collection, and incidence of treatment-related adverse reaction were counted. The influence of sex, age, disease remission status, bone marrow involvement at diagnosis, chemotherapy lines, number of chemotherapy, platelet count and number of CD34+ cells on the day before acquisition in peripheral blood on the collection results were analyzed to identify the risk factors associated with poor stem cell collection.

RESULTS

A total of 43 patients with lymphoma were enrolled, including 7 cases who received front-line steady-state mobilization, 19 cases who received preemptive intervention, and 17 cases who received recuse mobilization. The overall acquisition success rate was 58.1% (25/43) after use of plerixafor combined with G-CSF, and acquisition success rate of front-line steady-state mobilization, preemptive intervention, and recuse mobilization was 100%, 57.9%(11/19), and 41.2%(7/17), respectively. The excellent rate of collection was 18.6%(8/43). A total of 15 patients experienced mild to moderate treatment-related adverse reactions. The number of CD34+ cells < 5 cells/μl in peripheral blood on the day before collection was an independent risk factor affecting stem cell collection.

CONCLUSIONS

Plerixafor combined with G-CSF is a safe and effective mobilization regimen for patients with lymphoma. The number of CD34+ cells in peripheral blood on the day before collection is an predictable index for the evaluation of stem cell collection.

Second stem cell transplantation for treatment of relapsed/refractory multiple myeloma after first autologous stem cell transplant: A 15-year retrospective institutional analysis

Background

Multiple myeloma remains an incurable disease, with the majority of patients relapsing after autologous stem cell transplant (ASCT). After relapse, second transplant remains one of the therapeutic options, along with novel agents.

Methods

We reviewed the data of our patients who underwent ASCT for myeloma (N = 202) over the last two decades (2004-2019). Of these, 12 patients underwent a second transplant.

Results

Out of 12 patients, nine underwent second autologous stem cell transplant, whereas three received an allogeneic stem cell transplantation (Allo-SCT). Median progression-free survival (PFS) after the first ASCT was 32 months (5-84 months). Median interval between both the transplants was 35 months (4-159 months). Median age of our cohort which underwent second transplant was 56 years. Overall response rate (ORR) post-second transplant on day +100 was 83.3%, without any transplant-related mortality (TRM). With the use of preemptive plerixafor, none of our patients required a second day for stem cell harvest. Median CD34 dose of stem cells infused was 4.11 × 106/kg. Similar to the first ASCT, the median time to neutrophil and platelet engraftment was 11 and 12 days, respectively. At a median follow-up of 41 months, estimated 3-year PFS and overall survival (OS) was 37% ± 15% and 63% ± 15%, respectively.

Conclusion

">Among all relapsed myeloma patients who were transplant eligible, 11% underwent a second transplant. Second transplant is well tolerated with similar time to engraftment after first ASCT. Hence, we believe that second transplant is a feasible, cost-effective option in a resource-limited setting, which should be more widely utilized.

Motixafortide and G-CSF to mobilize hematopoietic stem cells for autologous transplantation in multiple myeloma: a randomized phase 3 trial

Autologous hematopoietic stem cell transplantation (ASCT) improves survival in multiple myeloma (MM). However, many individuals are unable to collect optimal CD34+ hematopoietic stem and progenitor cell (HSPC) numbers with granulocyte colony-stimulating factor (G-CSF) mobilization. Motixafortide is a novel cyclic-peptide CXCR4 inhibitor with extended in vivo activity. The GENESIS trial was a prospective, phase 3, double-blind, placebo-controlled, multicenter study with the objective of assessing the superiority of motixafortide + G-CSF over placebo + G-CSF to mobilize HSPCs for ASCT in MM. The primary endpoint was the proportion of patients collecting ≥6 × 106 CD34+ cells kg-1 within two apheresis procedures; the secondary endpoint was to achieve this goal in one apheresis. A total of 122 adult patients with MM undergoing ASCT were enrolled at 18 sites across five countries and randomized (2:1) to motixafortide + G-CSF or placebo + G-CSF for HSPC mobilization. Motixafortide + G-CSF enabled 92.5% to successfully meet the primary endpoint versus 26.2% with placebo + G-CSF (odds ratio (OR) 53.3, 95% confidence interval (CI) 14.12-201.33, P < 0.0001). Motixafortide + G-CSF also enabled 88.8% to meet the secondary endpoint versus 9.5% with placebo + G-CSF (OR 118.0, 95% CI 25.36-549.35, P < 0.0001). Motixafortide + G-CSF was safe and well tolerated, with the most common treatment-emergent adverse events observed being transient, grade 1/2 injection site reactions (pain, 50%; erythema, 27.5%; pruritis, 21.3%). In conclusion, motixafortide + G-CSF mobilized significantly greater CD34+ HSPC numbers within two apheresis procedures versus placebo + G-CSF while preferentially mobilizing increased numbers of immunophenotypically and transcriptionally primitive HSPCs. Trial Registration: ClinicalTrials.gov , NCT03246529.

Stem Cell Mobilization Yields with Daratumumab- and Lenalidomide-Containing Quadruplet Induction Therapy in Newly Diagnosed Multiple Myeloma: Findings from the MASTER and GRIFFIN Trials

For eligible patients with newly diagnosed multiple myeloma (NDMM), standard of care includes induction therapy followed by autologous stem cell transplantation (ASCT). Daratumumab as monotherapy and in combination treatment is approved across multiple lines of therapy for multiple myeloma (MM), and lenalidomide is an effective and commonly used agent for induction and maintenance therapy in MM. However, there is concern that lenalidomide and daratumumab given as induction therapy might impair mobilization of stem cells for ASCT. Therefore, we assessed stem cell mobilization in patients following frontline induction therapy in the MASTER and GRIFFIN phase 2 clinical studies by examining stem cell mobilization yields, apheresis attempts, and engraftment outcomes for patients from each study. Adult transplantation-eligible patients with NDMM received induction therapy consisting of daratumumab plus carfilzomib/lenalidomide/dexamethasone (D-KRd) for four 28-day cycles in the single-arm MASTER trial or lenalidomide/bortezomib/dexamethasone (RVd) with or without daratumumab (D) for four 21-day cycles in the randomized GRIFFIN trial, followed by stem cell mobilization and ASCT in both studies. Institutional practice differed regarding plerixafor use for stem cell mobilization; the strategies were upfront (ie, planned plerixafor use) or rescue (ie, plerixafor use only after mobilization parameters indicated failure with granulocyte colony-stimulating factor [G-CSF] alone). Descriptive analyses were used to summarize patient characteristics, stem cell mobilization yields, and engraftment outcomes. In MASTER, 116 D-KRd recipients underwent stem cell mobilization and collection at a median of 24 days after completing induction therapy. In GRIFFIN, 175 patients (D-RVd, n = 95; RVd, n = 80) underwent mobilization at a median of 27 days after completing D-RVd induction therapy and 24 days after completing RVd induction therapy. Among those who underwent mobilization and collection, 7% (8 of 116) of D-KRd recipients, 2% (2 of 95) of D-RVd recipients, and 6% (5 of 80) of RVd recipients did not meet the center-specific minimally required CD34⁺ cell yield in the first mobilization attempt; however, nearly all collected sufficient stem cells for ASCT on remobilization. Among patients who underwent mobilization, plerixafor use, either upfront or as a rescue strategy, was higher in patients receiving D-KRd (97%; 112 of 116) and D-RVd (72%; 68 of 95) compared with those receiving RVd (55%; 44 of 80). The median total CD34⁺ cell collection was 6.0 × 10⁶/kg (range, 2.2 to 13.9 × 10⁶/kg) after D-KRd induction, 8.3 × 10⁶/kg (range, 2.6 to 33.0 × 10⁶/kg) after D-RVd induction, and 9.4 × 10⁶/kg (range, 4.1 to 28.7 × 10⁶/kg) after RVd induction; the median days for collection were 2, 2, and 1, respectively. Among patients who underwent mobilization, 98% (114 of 116) of D-KRd patients, 99% (94 of 95) of D-RVd patients, and 98% (78 of 80) of RVd patients underwent ASCT using median CD34⁺ cell doses of 3.2 × 10⁶/kg, 4.2 × 10⁶/kg, and 4.8 × 10⁶/kg, respectively. The median time to neutrophil recovery was 12 days in all 3 treatment groups across the 2 trials. Because both trials used different criteria to define platelet recovery, data on platelet engraftment using the same criteria are not available. Four cycles of daratumumab- and lenalidomide-based quadruplet induction therapy had a minimal impact on stem cell mobilization and allowed predictable stem cell harvesting and engraftment in all patients who underwent ASCT. Upfront plerixafor strategy may be considered, but many patients were successfully collected with the use of G-CSF alone or rescue plerixafor.

Recent Developments in the Synthesis and Anticancer Activity of Indole and Its Derivatives

Heterocyclic compounds are a class of compounds that is deeply intertwined with biological processes and is found in about 90% of commercially available medicines. They serve a critical function in medicinal chemistry and are focused in the field of medication development for their intensive research due to their broad variety of biological effects because of their intriguing molecular architecture, such as indoles are good candidates for drug development. It is a bicyclic structure consisting of a six-membered benzene ring fused to a five-membered pyrrole ring with several pharmacophores that yield a library of different lead compounds. Human cancer cells have been demonstrated to be inhibited by indoles in the development of new anticancer medicines. This is the first comprehensive review to focus on current methodologies for incorporating indole moiety, with their mechanistic targets as anticancer drugs, in order to shed light on the logical development of indole-based anticancer treatment options with high efficacy. This compiled data may serve as a benchmark for modifying existing ligands in order to design novel potent molecules through excellent yield synthesis techniques.

SAR based Review on Diverse Heterocyclic Compounds with Various Potential Molecular Targets in the Fight against COVID-19: A Medicinal Chemist Perspective

Coronavirus disease (COVID-19) was reported to be transmitted from bats to humans and, became a pandemic in 2020. COVID-19 is responsible for millions of deaths worldwide and still, the numbers are increasing. Further, despite the availability of vaccines, mutation in the virus continuously poses a threat of re-emergence of the more lethal form of the virus. So far, the repurposing of drugs has been exercised heavily for the identification of therapeutic agents against COVID-19, which led FDA to approve many drugs for the same e.g., remdesivir, favipiravir, ribavirin, etc. The anti-COVID drugs explored via other approaches include nirmatrelvir (used in combination with ritonavir as Paxlovid), tixagevimab and cilgavimab (both used in combination with each other) and others. However, these approved drugs failed to achieve a significant clinical outcome. Globally, natural bioactive have also been explored for anti-COVID-19 effects, based on their traditional medicinal values. Although the clinical findings suggest that FDA-approved drugs and natural bioactives can help reducing the overall mortality rate but the significant clinical outcome was not achieved. Therefore, the focus has been shifted towards new drug development. In line with that, a lot of work has been done and still going on to explore heterocyclic compounds as potent anti- COVID-19 drugs. Several heterocyclic scaffolds have been previously reported with potent antiinflammatory, anticancer, anti-viral, antimicrobial and anti-tubercular effects. Few of them are under consideration for clinical trials whereas others are under preclinical investigation. Hence, this review discusses the evidence of rationally designed and tested heterocyclic compounds acting on different targets against COVID-19. The present article will help the researches and will serve as a pivotal resource in the design and development of novel anti-COVID-19 drugs.

N-Heterocyclic Compounds, In silico Molecular Docking Studies, and In vitro Enzyme Inhibition Effect against Acetylcholinesterase Inhibitors

BACKGROUND

This work contains the synthesis of seven new N-heterocyclic compounds bearing imidazole, benzimidazole, pyridine, and morpholine moieties.

OBJECTIVES

We aimed to synthesize N-heterocyclic compounds for a more effective drug candidate to increase the amount of acetylcholine in synapses in Alzheimer's disease. All compounds were characterized by 1H NMR, 13C NMR, FTIR and elemental analysis. Enzyme inhibition activity of all compounds against acetylcholinesterase was investigated, which is an indirect treatment for Alzheimer's. Molecular docking was applied to estimate the binding energy of these compounds to the acetylcholinesterase.

METHODS

All compounds were synthesized from reactions of 2 equivalents of N-heterocyclic starting material and 1 equivalent of 4,4'-bis(chloromethyl)-1,1'-biphenyl. The inhibition parameters of IC50 and Ki were calculated by the spectrophotometric method. AutoDock4 was used to define the binding pose of the compounds.

RESULTS

Ki values were found in the range of 80.03 ± 19.64 to 5014.98 ± 1139.60 nM for AChE as an enzyme inhibition strategy, which is an important parameter for the treatment of neurodegenerative such as Alzheimer's disease. In this study, molecular docking is exerted to predict the binding energy of heterocyclic compounds (especially 2, 3, and 5) against acetylcholinesterase enzyme. Their docking binding energies are in good agreement with experimental findings.

CONCLUSION

These new syntheses are drugs that can be used as AChE inhibitors in Alzheimer's disease.

Plerixafor on a WHIM - Promise or Fantasy of a New CXCR4 Inhibitor for This Rare, but Important Syndrome?

Warts, Hypogammaglobulinemia, Infections and Myelokathexis (WHIM) is a primary immunodeficiency syndrome. Patients with WHIM syndrome are more susceptible to human papillomavirus (HPV) infections and commonly present to a dermatologist with recalcitrant to treatment warts. Other cardinal features of WHIM syndrome include recurrent sinopulmonary bacterial infections, neutropenia/lymphopenia, low levels of immunoglobulins (IgG, IgA, IgM) and myelokathexis. Research demonstrated that truncating gain-of-function mutations of the C-X-C chemokine receptor type 4 gene (CXCR4) are responsible for this disease. Plerixafor, a specific small molecule antagonist of CXCR4, is currently used for peripheral blood hematopoietic stem cell (HSC) mobilization in stem cell transplant recipients. It has recently shown promise for the treatment of WHIM syndrome in phase I/II clinical trials. In this paper we review the emerging patient clinical data for this medication and highlight the role of CXCR4 in other important skin diseases including keratinocyte carcinomas, psoriasis and cutaneous T-cell lymphoma.

Limitations of bacterial culture, viral PCR, and tulathromycin susceptibility from upper respiratory tract samples in predicting clinical outcome of tulathromycin control or treatment of bovine respiratory disease in high-risk feeder heifers

A cross-sectional prospective cohort study including 1026 heifers administered tulathromycin due to high risk of clinical signs of bovine respiratory disease (BRD), measured poor association between BRD clinical outcomes and results of bacterial culture and tulathromycin susceptibility from BRD isolates of deep nasopharyngeal swabs (DNS) and adequate association with viral polymerase chain reaction (PCR) results from nasal swabs. Isolation rates from DNS collected on day-0 and at 1st BRD-treatment respectively were: Mannheimia haemolytica (10.9% & 34.1%); Pasteurella multocida (10.4% & 7.4%); Mycoplasma bovis (1.0% & 36.6%); and Histophilus somni (0.7% & 6.3%). Prevalence of BRD viral nucleic acid on nasal swabs collected exclusively at 1st BRD-treatment were: bovine parainfluenza virus type-3 (bPIV-3) 34.1%; bovine viral diarrhea virus (BVDV) 26.3%; bovine herpes virus type-1 (BHV-1) 10.8%; and bovine respiratory syncytial virus (BRSV) 54.1%. Increased relative risk, at 95% confidence intervals, of 1st BRD-treatment failure was associated with positive viral PCR results: BVDV 1.39 (1.17-1.66), bPIV-3 1.26 (1.06-1.51), BHV-1 1.52 (1.25-1.83), and BRSV 1.35 (1.11-1.63) from nasal swabs collected at 1st BRD-treatment and culture of M. haemolytica 1.23 (1.00-1.51) from DNS collected at day-0. However, in this population of high-risk feeder heifers, the predictive values of susceptible and resistant isolates had inadequate association with BRD clinical outcome. These results indicate, that using tulathromycin susceptibility testing of isolates of M. haemolytica or P. multocida from DNS collected on arrival or at 1st BRD-treatment to evaluate tulathromycin clinical efficacy, is unreliable.

Synthetic and Naturally Occurring Heterocyclic Anticancer Compounds with Multiple Biological Targets

Cancer is a complex group of diseases initiated by abnormal cell division with the potential of spreading to other parts of the body. The advancement in the discoveries of omics and bio- and cheminformatics has led to the identification of drugs inhibiting putative targets including vascular endothelial growth factor (VEGF) family receptors, fibroblast growth factors (FGF), platelet derived growth factors (PDGF), epidermal growth factor (EGF), thymidine phosphorylase (TP), and neuropeptide Y4 (NY4), amongst others. Drug resistance, systemic toxicity, and drug ineffectiveness for various cancer chemo-treatments are widespread. Due to this, efficient therapeutic agents targeting two or more of the putative targets in different cancer cells are proposed as cutting edge treatments. Heterocyclic compounds, both synthetic and natural products, have, however, contributed immensely to chemotherapeutics for treatments of various diseases, but little is known about such compounds and their multimodal anticancer properties. A compendium of heterocyclic synthetic and natural product multitarget anticancer compounds, their IC50, and biological targets of inhibition are therefore presented in this review.

N-Heterocyclic Carbene Iron Complexes as Anticancer Agents: In Vitro and In Vivo Biological Studies

Cisplatin and its derivatives are commonly used in chemotherapeutic treatments of cancer, even though they suffer from many toxic side effects. The problems that emerge from the use of these metal compounds led to the search for new complexes capable to overcome the toxic side effects. Here, we report the evaluation of the antiproliferative activity of Fe(II) cyclopentadienyl complexes bearing n-heterocyclic carbene ligands in tumour cells and their in vivo toxicological profile. The in vitro antiproliferative assays demonstrated that complex Fe1 displays the highest cytotoxic activity both in human colorectal carcinoma cells (HCT116) and ovarian carcinoma cells (A2780) with IC₅₀ values in the low micromolar range. The antiproliferative effect of Fe1 was even higher than cisplatin. Interestingly, Fe1 showed low in vivo toxicity, and in vivo analyses of Fe1 and Fe2 compounds using colorectal HCT116 zebrafish xenograft showed that both reduce the proliferation of human HCT116 colorectal cancer cells in vivo.

Structure Activity Relationship of Key Heterocyclic Anti-Angiogenic Leads of Promising Potential in the Fight against Cancer

Pathological angiogenesis is a hallmark of cancer; accordingly, a number of anticancer FDA-approved drugs act by inhibiting angiogenesis via different mechanisms. However, the development process of the most potent anti-angiogenics has met various hurdles including redundancy, multiplicity, and development of compensatory mechanisms by which blood vessels are remodeled. Moreover, identification of broad-spectrum anti-angiogenesis targets is proved to be required to enhance the efficacy of the anti-angiogenesis drugs. In this perspective, a proper understanding of the structure activity relationship (SAR) of the recent anti-angiogenics is required. Various anti-angiogenic classes have been developed over the years; among them, the heterocyclic organic compounds come to the fore as the most promising, with several drugs approved by the FDA. In this review, we discuss the structure–activity relationship of some promising potent heterocyclic anti-angiogenic leads. For each lead, a molecular modelling was also carried out in order to correlate its SAR and specificity to the active site. Furthermore, an in silico pharmacokinetics study for some representative leads was presented. Summarizing, new insights for further improvement for each lead have been reviewed.

A Computational Approach to Explore the Interaction of Semisynthetic Nitrogenous Heterocyclic Compounds with the SARS-CoV-2 Main Protease

In the context of the ongoing coronavirus disease 2019 (COVID-19) pandemic, numerous attempts have been made to discover new potential antiviral molecules against its causative agent, SARS-CoV-2, many of which focus on its main protease (M^pro). We hereby used two approaches based on molecular docking simulation to explore the interaction of four libraries of semisynthetic nitrogenous heterocyclic compounds with M^pro. Libraries L1 and L2 contain 52 synthetic derivatives of the natural compound 2-propylquinoline, whereas libraries L3 and L4 contain 65 compounds synthesized using the natural compound physostigmine as a precursor. Validation through redocking suggested that the rigid receptor and flexible receptor approaches used for docking were suitable to model the interaction of this type of compounds with the target protein, although the flexible approach seemed to provide a more realistic representation of interactions within the active site. Using empirical energy score thresholds, we selected 58 compounds from the four libraries with the most favorable energy estimates. Globally, favorable estimates were obtained for molecules with two or more substituents, putatively accommodating in three or more subsites within the M^pro active site. Our results pave the way for further experimental evaluation of the selected compounds as potential antiviral agents against SARS-CoV-2.

Analysis of Trans-Ancestral SLE Risk Loci Identifies Unique Biologic Networks and Drug Targets in African and European Ancestries

Systemic lupus erythematosus (SLE) is a multi-organ autoimmune disorder with a prominent genetic component. Individuals of African ancestry (AA) experience the disease more severely and with an increased co-morbidity burden compared to European ancestry (EA) populations. We hypothesize that the disparities in disease prevalence, activity, and response to standard medications between AA and EA populations is partially conferred by genomic influences on biological pathways. To address this, we applied a comprehensive approach to identify all genes predicted from SNP-associated risk loci detected with the Immunochip. By combining genes predicted via eQTL analysis, as well as those predicted from base-pair changes in intergenic enhancer sites, coding-region variants, and SNP-gene proximity, we were able to identify 1,731 potential ancestry-specific and trans-ancestry genetic drivers of SLE. Gene associations were linked to upstream and downstream regulators using connectivity mapping, and predicted biological pathways were mined for candidate drug targets. Examination of trans-ancestral pathways reflect the well-defined role for interferons in SLE and revealed pathways associated with tissue repair and remodeling. EA-dominant genetic drivers were more often associated with innate immune and myeloid cell function pathways, whereas AA-dominant pathways mirror clinical findings in AA subjects, suggesting disease progression is driven by aberrant B cell activity accompanied by ER stress and metabolic dysfunction. Finally, potential ancestry-specific and non-specific drug candidates were identified. The integration of all SLE SNP-predicted genes into functional pathways revealed critical molecular pathways representative of each population, underscoring the influence of ancestry on disease mechanism and also providing key insight for therapeutic selection.

Reaction Cycles of Halogen Species in the Immune Defense: Implications for Human Health and Diseases and the Pathology and Treatment of COVID-19

There is no vaccine or specific antiviral treatment for COVID-19, which is causing a global pandemic. One current focus is drug repurposing research, but those drugs have limited therapeutic efficacies and known adverse effects. The pathology of COVID-19 is essentially unknown. Without this understanding, it is challenging to discover a successful treatment to be approved for clinical use. This paper addresses several key biological processes of reactive oxygen, halogen and nitrogen species (ROS, RHS and RNS) that play crucial physiological roles in organisms from plants to humans. These include why superoxide dismutases, the enzymes to catalyze the formation of H₂O₂, are required for protecting ROS-induced injury in cell metabolism, why the amount of ROS/RNS produced by ionizing radiation at clinically relevant doses is ~1000 fold lower than the endogenous ROS/RNS level routinely produced in the cell and why a low level of endogenous RHS plays a crucial role in phagocytosis for immune defense. Herein we propose a plausible amplification mechanism in immune defense: ozone-depleting-like halogen cyclic reactions enhancing RHS effects are responsible for all the mentioned physiological functions, which are activated by H₂O₂ and deactivated by NO signaling molecule. Our results show that the reaction cycles can be repeated thousands of times and amplify the RHS pathogen-killing (defense) effects by 100,000 fold in phagocytosis, resembling the cyclic ozone-depleting reactions in the stratosphere. It is unraveled that H₂O₂ is a required protective signaling molecule (angel) in the defense system for human health and its dysfunction can cause many diseases or conditions such as autoimmune disorders, aging and cancer. We also identify a class of potent drugs for effective treatment of invading pathogens such as HIV and SARS-CoV-2 (COVID-19), cancer and other diseases, and provide a molecular mechanism of action of the drugs or candidates.

Efficacy of gamithromycin injection administered intramuscularly against bacterial swine respiratory disease

The aim of this study is to evaluate the safety and efficacy of gamithromycin (GAM) for the treatment of naturally occurring bacterial swine respiratory disease (SRD) administered IM. A total of 240 pigs (nine-weeks old) were selected from two sites in Heilongjiang Province of China. The pigs showed severe signs of respiratory disease. Among them, 120 pigs were randomly divided into 4 groups of low dose (3 mg/kg), middle dose (6 mg/kg), high dose (12 mg/kg) GAM IM injection and 2.5 mg/kg tulathromycin (TUL) IM injection (positive control group) for phase II clinical trial to screen effective therapeutic dose. The other 120 pigs were randomly divided into 2 groups of 6 mg/kg GAM IM injection and 2.5 mg/kg TUL IM injection (positive control group) for phase III clinical trial to further confirm the efficacy. Animals were clinically observed daily for 14 days after treatment initiation. The predominant pathogens present in pretreatment respiratory tract samples were Streptococcus suis (S. suis) and Actinobacillus pleuropneumoniae (A. pleuropneumoniae). Haemophilus parasuis (H. parasuis) and Pasteurella multocida (P. multocida) were also found in the respiratory tract. All isolates were subjected to in vitro sensitivity testing and the measured minimal inhibitory concentrations (MIC) of GAM were from 0.0625 μg/mL to 8 μg/mL. In all treatment groups, rectal temperature dropped and clinical index (mental status and respiratory symptom) significantly improved after treatment (P ≤ .05). As a result, 82.76% animals treated with the 6 mg/kg GAM injection were cured. This was significantly higher than that of 3 mg/kg GAM injection (P ≤ .05) and similar to that of 12 mg/kg GAM injection and 2.5 mg/kg TUL injection (P > .05) in phase II clinical trial. In phase III clinical trial, 80.70% of animals treated with the 6 mg/kg GAM injection were cured and the cure rate was similar to that of 2.5 mg/kg TUL injection (P > .05). In conclusion, we recommended a single dose (6 mg/kg) of GAM IM injection for the treatment of bacterial SRD.

Chemokine Receptor Antagonists in Combination with Morphine as a Novel Strategy for Opioid Dose Reduction in Pain Management

INTRODUCTION

Although opioids are widely prescribed for pain, in many circumstances, they have only modest efficacy. Preclinical studies have shown that chemokines, immune mediators released during tissue injury and inflammation, can desensitize opioid receptors and block opioid analgesia by a process termed "heterologous desensitization." The present studies tested the hypothesis that in evoked pain, certain chemokine receptor antagonists (CRAs), given with a submaximal dose of morphine, would result in enhanced morphine potency.

METHODS

Three rodent pain assays were used: incisional pain in rats, the cold-water tail flick test in rats, and the formalin test in mice. The FDA-approved, commercially available CRAs, maraviroc and AMD3100, were used. They block the chemokine receptors and ligands, CCR5/CCL5 (RANTES) and CXCR4/CXCL4 (SDF-1α), respectively.

RESULTS

In the incisional pain assay, it was found that the combination of a single CRA, or of both CRAs, with morphine significantly shifted the morphine dose-response curve to the left, as much as 3.3-fold. In the cold-water tail flick and formalin tests, significant increases of the antinociceptive effects of morphine were also observed when combined with CRAs.

CONCLUSIONS

These results support the potential of a new "opioid-sparing" approach for pain treatment, which combines CRAs with reduced doses of morphine.

Tulathromycin treatment does not affect bacterial dissemination or clearance of Brucella melitensis 16M following experimental infection of goats

Brucellosis in sheep and goats, a zoonotic disease primarily associated with Brucella melitensis infections, causes significant economic losses and public health concerns worldwide. Although control measures are effective, economic limitations and nomadic lifestyles may limit vaccination coverage, and test and removal policies may not be feasible. In this study, we evaluated the effects of therapy with a long acting antimicrobial tulathromycin on the pathogenesis of brucellosis. Thirty-five goats were randomly assigned for experimental infection with B. melitensis strain 16M while open or during mid-gestation. Approximately half of the animals in each group were then treated with tulathromycin and subsequently assessed for the development of humoral responses to infection, clinical presentation, and bacterial dissemination and colonization. All animals, regardless of treatment group were successfully challenged with B. melitensis 16M demonstrated by bacterial recovery from conjunctival swabs and development of positive antibody titers. In goats infected while open, no animals aborted and Brucella was recovered from only one animal in tulathromycin-treated and one animal from the untreated group. Tulathromycin treatment of pregnant goats did not prevent abortion nor did it reduce bacterial dissemination, colonization, or shedding. Our data suggests that treatment of goats in mid-gestation with tulathromycin at the labeled dose does not influence disease pathogenesis or tissue colonization after experimental B. melitensis challenge.

'Peptide receptor radionuclide therapy in the management of advanced pheochromocytoma and paraganglioma: A systematic review and meta-analysis'

OBJECTIVE

Inoperable and metastatic pheochromocytomas and paragangliomas (PPGLs) present a therapeutic challenge with current treatment options being limited to radiolabelled meta-iodo-benzyl-guanidine (MIBG) and systemic chemotherapy. Peptide receptor radionuclide therapy (PRRT) seems to be a promising option for these patients with few studies reporting favourable response. This systematic review was conducted to evaluate the efficacy and safety of PRRT in patients with advanced PPGLs.

METHODS

This review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines. Searches in PubMed, Scopus and Embase were made using relevant keywords and articles up to May 2019 were included. Data on efficacy and toxicity were extracted from the individual articles, and pooled estimates were generated using meta-analysis.

RESULTS

Twelve articles consisting of 201 patients with advanced PPGLs were included. Overall, treatment with PRRT achieved an objective response rate of 25% (95% CI: 19%-32%) and a disease control rate of 84% (95% CI: 77%-89%). Clinical and biochemical responses were seen in 61% and 64% of the patients, respectively. Among the PRRTs, similar tumour response rates were noted for ⁹⁰ Y-yttrium- and ¹⁷⁷ Lu-lutetium-based agents. Treatment-related adverse effects were minimal with grade 3/4 neutropenia, thrombocytopenia, lymphopenia and nephrotoxicity observed in 3%, 9%, 11% and 4% of the patients, respectively. Treatment discontinuation was noted in five out of 102 patients.

CONCLUSIONS

Peptide receptor radionuclide therapy is a safe and efficacious treatment option for advanced PPGLs and may be considered a viable alternative to chemotherapy and I-¹³¹ MIBG.

Macrophage Exclusion after Radiation Therapy (MERT): A First in Human Phase I/II Trial using a CXCR4 Inhibitor in Glioblastoma

PURPOSE

Preclinical studies have demonstrated that postirradiation tumor revascularization is dependent on a stromal cell-derived factor-1 (SDF-1)/C-X-C chemokine receptor type 4 (CXCR4)-driven process in which myeloid cells are recruited from bone marrow. Blocking this axis results in survival improvement in preclinical models of solid tumors, including glioblastoma (GBM). We conducted a phase I/II study to determine the safety and efficacy of Macrophage Exclusion after Radiation Therapy (MERT) using the reversible CXCR4 inhibitor plerixafor in patients with newly diagnosed glioblastoma.

PATIENTS AND METHODS

We enrolled nine patients in the phase I study and an additional 20 patients in phase II using a modified toxicity probability interval (mTPI) design. Plerixafor was continuously infused intravenously via a peripherally inserted central catheter (PICC) line for 4 consecutive weeks beginning at day 35 of conventional treatment with concurrent chemoradiation. Blood serum samples were obtained for pharmacokinetic analysis. Additional studies included relative cerebral blood volume (rCBV) analysis using MRI and histopathology analysis of recurrent tumors.

RESULTS

Plerixafor was well tolerated with no drug-attributable grade 3 toxicities observed. At the maximum dose of 400 μg/kg/day, biomarker analysis found suprathreshold plerixafor serum levels and an increase in plasma SDF-1 levels. Median overall survival was 21.3 months [95% confidence interval (CI), 15.9-NA] with a progression-free survival of 14.5 months (95% CI, 11.9-NA). MRI and histopathology support the mechanism of action to inhibit postirradiation tumor revascularization.

CONCLUSIONS

Infusion of the CXCR4 inhibitor plerixafor was well tolerated as an adjunct to standard chemoirradiation in patients with newly diagnosed GBM and improves local control of tumor recurrences.

Immuno-modulating properties of Tulathromycin in porcine monocyte-derived macrophages infected with porcine reproductive and respiratory syndrome virus

Porcine reproductive and respiratory syndrome virus (PRRSV) is a positive-stranded RNA virus that grows in macrophages and causes acute pneumonia in pigs. PRRSV causes devastating losses to the porcine industry. However, due to its high antigenic variability and poorly understood immunopathogenesis, there is currently no effective vaccine or treatment to control PRRSV infection. The common occurrence of PRRSV infection with bacterial infections as well as its inflammatory-driven pathobiology raises the question of the value of antibiotics with immunomodulating properties for the treatment of the disease it causes. The macrolide antibiotic Tulathromycin (TUL) has been found to exhibit potent anti-inflammatory and immunomodulating properties in cattle and pigs. The aim of this study was to characterize the anti-viral and immunomodulating properties of TUL in PRRSV-infected porcine macrophages. Our findings indicate that blood monocyte-derived macrophages are readily infected by PRRSV and can be used as an effective cellular model to study PRRSV pathogenesis. TUL did not change intracellular or extracellular viral titers, not did it alter viral receptors (CD163 and CD169) expression on porcine macrophages. In contrast, TUL exhibited potent immunomodulating properties, which therefore occurred in the absence of any direct antiviral effects against PRRSV. TUL had an additive effect with PRRSV on the induction of macrophage apoptosis, and inhibited virus-induced necrosis. TUL significantly attenuated PRRSV-induced macrophage pro-inflammatory signaling (CXCL-8 and mitochondrial ROS production) and prevented PRRSV inhibition of non-opsonized and opsonized phagocytic function. Together, these data demonstrate that TUL inhibits PRRSV-induced inflammatory responses in porcine macrophages and protects against the phagocytic impairment caused by the virus. Research in live pigs is warranted to assess the potential clinical benefits of this antibiotic in the context of virally induced inflammation and tissue injury.

The past, present and future of potential small-molecule drugs targeting p53-MDM2/MDMX for cancer therapy

The p53 gene, a well-known tumor suppressor gene, plays a crucial role in cell cycle regulation, DNA repair, cell differentiation, and apoptosis. MDM2 exerts p53-dependent activity mainly by binding to p53 protein to form MDM2-p53 negative feedback loop. In addition, MDM2 is involved in a number of pathways that regulate cell proliferation and apoptosis, playing a p53-independent role. The p53 binding domain of MDMX bind to p53 transcriptional activation domain, inhibiting the transcriptional activity of p53 on its downstream genes, but does not mediate the degradation of p53. The anti-tumor effect is exerted by inhibiting the interaction between the MDM2/MDMX protein and the p53 protein by a small-molecule or by restoring the activity of the p53 protein. This review describes in the structural features, biological functions and mechanisms of p53-MDM2/MDMX, and summarizes small-molecule targeting p53-MDM2/MDMX.

Mutant prevention and minimum inhibitory concentration drug values for enrofloxacin, ceftiofur, florfenicol, tilmicosin and tulathromycin tested against swine pathogens Actinobacillus pleuropneumoniae, Pasteurella multocida and Streptococcus suis

Actinobacillus pleuropneumoniae, Pasteurella multocida and Streptococcus suis are prevalent bacterial causes of swine infections. Morbidity, mortality and positively impacting the financial burden of infection occurs with appropriate antimicrobial therapy. Increasing antimicrobial resistance complicates drug therapy and resistance prevention is now a necessity to optimize therapy and prolong drug life. Mutant bacterial cells are said to arise spontaneously in bacterial densities of 107-109 or greater colony forming units/ml. Antibiotic drug concentration inhibiting growth of the least susceptible cell in these high density populations has been termed the mutant prevention concentration (MPC). In this study MPC and minimum inhibitory concentration (MIC) values of ceftiofur, enrofloxacin, florfenicol, tilmicosin and tulathromycin were determined against the swine pathogens A. pleuropneumoniae, P.multocida and S. suis. The following MIC90/MPC90 values (mg/L) for 67 A. pleuropneumoniae and 73 P. multocida strains respectively were as follows: A. pleuropneumoniae 0.031/0.5, ≤0.016/0.5, 0.5/2, 4/32, 2/32; P. multocida 0.004/0.25, 0.016/0.125, 0.5/0.5, 8/16, 0.5/1. For 33 S. suis strains, MIC90 values (mg/L) respectively were as follows: 1, 0.25, 4, ≥8 and ≥8. A total of 16 S. suis strains with MIC values of 0.063-0.5 mg/L to ceftiofur and 0.25-0.5 mg/L to enrofloxacin were tested by MPC; MPC values respectively were 0.5 and 1 mg/L respectively. MPC concentrations provide a dosing target which may serve to reduce amplification of bacterial subpopulations with reduced antimicrobial susceptibility. Drug potency based on MIC90 values was ceftiofur > enrofloxacin >florfenicol = tulathromycin > tilmicosin; based on MPC90 values was enrofloxacin > ceftiofur > tulathromycin > florfenicol ≥ tilmicosin.

Plerixafor for the Treatment of WHIM Syndrome

WHIM syndrome (warts, hypogammaglobulinemia, infections, and myelokathexis), a primary immunodeficiency disorder involving panleukopenia, is caused by autosomal dominant gain-of-function mutations in CXC chemokine receptor 4 (CXCR4). Myelokathexis is neutropenia caused by neutrophil retention in bone marrow. Patients with WHIM syndrome are often treated with granulocyte colony-stimulating factor (G-CSF), which can increase neutrophil counts but does not affect cytopenias other than neutropenia. In this investigator-initiated, open-label study, three severely affected patients with WHIM syndrome who could not receive G-CSF were treated with low-dose plerixafor, a CXCR4 antagonist, for 19 to 52 months. Myelofibrosis, panleukopenia, anemia, and thrombocytopenia were ameliorated, the wart burden and frequency of infection declined, human papillomavirus-associated oropharyngeal squamous-cell carcinoma stabilized, and quality of life improved markedly. Adverse events were mainly infections attributable to the underlying immunodeficiency. One patient died from complications of elective reconstructive surgery. (Funded by the National Institutes of Health.).

Pharmacokinetic/pharmacodynamic (PK/PD) evaluation of tulathromycin against Haemophilus parasuis in an experimental neutropenic guinea pig model

The objective of the study was to develop an ex-vivo PK/PD model of intramuscular (IM) administration of tulathromycin and to test its efficacy against Haemophilus parasuis (H. parasuis) infection in intraperitoneal-inoculated neutropenic guinea pigs. The pharmacokinetics (PKs) of tulathromycin at doses of 1 and 10 mg/kg in H. parasuis-infected neutropenic guinea pig were studied by high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). In vitro minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), mutant prevention concentration (MPC), post-antibiotic effect (PAE) and dynamic time-kill curve experiments were carried out using H. parasuis strain 13R. Tulathromycin exhibited concentration-dependent activity and PAE persisted long after administration of the antibiotic. The ratio of the 24-h area under the concentration–time curve (AUC) to MIC in serum (AUC_24h/MIC_serum) was recognized as an important PK/PD parameter that positively correlated with the in vitro antibacterial effectiveness of tulathromycin (R² = 0.9961 or R² = 1). For the 1 and 10 mg/kg treatments with tulathromycin, the values of AUC_24h/MIC for H. parasuis bacteriostatic action, bactericidal action and virtual bacterial eradication were respectively 22.73, 34.5 and 88.03 h for the 1 mg/kg treatment and respectively 24.94, 30.94 and 49.92 h for the 10 mg/kg treatment. In addition, we demonstrated that doses of 7.2–8.0 mg/kg of tulathromycin resulted in high eradication rates (99.99%). Using a previously published conversion factor of 0.296, we were able to estimate an approximate dose, 2.1–2.4 mg/kg, that should also obtain high eradication rates in the target animal, pigs. This study can help optimize tulathromycin efficacy against H. parasuis infections in swine farming.

Modeling Idiopathic Pulmonary Fibrosis in Humanized Severe Combined Immunodeficient Mice

Idiopathic pulmonary fibrosis (IPF) is a fibrotic lung disease of unknown etiopathogenesis with limited therapeutic options. IPF is characterized by an abundance of fibroblasts and loss of epithelial progenitors, which cumulates in unrelenting fibrotic lung remodeling and loss of normal oxygenation. IPF has been challenging to model in rodents; nonetheless, mouse models of lung fibrosis provide clues as to the natural progression of lung injury and remodeling, but many have not been useful in predicting efficacy of therapeutics in clinical IPF. We provide a detailed methodologic description of various iterations of humanized mouse models, initiated by the i.v. injection of cells from IPF lung biopsy or explants specimens into severe combined immunodeficiency (SCID)/beige or nonobese diabetic SCID γ mice. Unlike cells from normal lung samples, IPF cells promote persistent, nonresolving lung remodeling in SCID mice. Finally, we provide examples and discuss potential advantages and pitfalls of human-specific targeting approaches in a humanized SCID model of pulmonary fibrosis.

Incidence of Second Primary Malignancies after Autologous Transplantation for Multiple Myeloma in the Era of Novel Agents

The advent of novel agents for multiple myeloma (MM) is cause for a re-examination of the incidence of second primary malignancies (SPMs). We examined the SPM rate in MM patients who were enrolled in the prospective observational CALM (Collaboration to Collect Autologous Transplant outcome in Lymphoma and Myeloma) study. Between 2008 and 2012, 3204 patients with MM underwent a first autologous hematopoietic stem cell transplantation. Plerixafor was used as a mobilizing agent for patients with poor (or potentially poor) stem cell mobilization as defined by the respective centers. A total of 135 patients developed SPMs, with a cumulative incidence of 5.3% (95% confidence interval, 4.4 to 6.3) at 72 months. Ninety-four patients developed solid tumors, 30 developed hematologic malignancies, and 11 developed an SPM of an unknown type. The cumulative incidence of known hematologic and solid malignancies were 1.4% and 3.6%, respectively, at 72 months. In a univariate analysis, use of radiotherapy, type of induction regimen, hematopoietic stem cell dose, poor mobilizer status, plerixafor use, and sex did not influence the cumulative incidence of SPMs. Only age over 65 years was statistically associated with an increased incidence. Overall, the incidence of SPMs was comparable to earlier estimations of SPMs in MM.

Induction of immunogenic cell death of tumors by newly synthesized heterocyclic quinone derivative

Many cancer types are serious diseases causing mortality, and new therapeutics with improved efficacy and safety are required. Immuno-(cell)-therapy is considered as one of the promising therapeutic strategies for curing intractable cancer. In this study, we tested R2016, a newly developed heterocyclic quinone derivative, for induction of immunogenic tumor cell death and as a possible novel immunochemotherapeutic. We studied the anti-cancer effects of R2016 against LLC, a lung cancer cell line and B16F10, a melanoma cell line. LLC (non-immunogenic) and B16F10 (immunogenic) cells were killed by R2016 in dose-dependent manner. R2016 reduced the viability of both LLC and B16F10 tumor cells by inducing apoptosis and necrosis, while it demonstrated no cytotoxicity against normal splenocytes. Expression of immunogenic death markers on the cell surface of R2016 treated tumor cells including calreticulin (CRT) and heat shock proteins (HSPs) was increased along with the induction of their genes. Increased CRT expression correlated with dendritic cell (DC) uptake of dying tumor cells: the proportion of CRT⁺CD11c⁺cells was increased in the R2016-treated group. The gene transcription of Calr3, Hspb1, and Tnfaip6, which are related to immunogenicity induction of dead cells, was up-regulated in the R2016 treated tumor cells. On the other hand, ANGPT1, FGF7, and URGCP gene levels were down-regulated by R2016 treatment. This data suggests that R2016 induced immunogenic tumor cell death, and suggests R2016 as an effective anti-tumor immunochemotherapeutic modality.

How to manage poor mobilizers for high dose chemotherapy and autologous stem cell transplantation?

Today, peripheral blood stem cells are the preferred source of stem cells over bone marrow. Therefore, mobilization plays a crutial role in successful autologous stem cell transplantation. Poor mobilization is generally defined as failure to achieve the target level of at least 2×10⁶ CD34⁺ cells/kg body weight. There are several strategies to overcome poor mobilization: 1) Larger volume Leukapheresis (LVL) 2) Re-mobilization 3) Plerixafor 4) CM+Plerixafor (P)+G-CSF and 5) Bone Marrow Harvest. In this review, the definitions of successful and poor mobilization are discussed. Management strategies for poor mobilization are defined. The recent research on new agents are included.

Clinical disease and lung lesions in calves experimentally inoculated with Histophilus somni five days after metaphylactic administration of tildipirosin or tulathromycin

OBJECTIVE

To compare clinical disease and lung lesions in calves experimentally inoculated with Histophilus somni 5 days after metaphylactic administration of tildipirosin or tulathromycin. ANIMALS Twenty-four 3-month-old Holstein and Holstein-crossbreed steers.

PROCEDURES

Calves were randomly allocated to 3 groups of 8 calves. On day 0, calves in group 1 received tildipirosin (4 mg/kg, SC), calves in group 2 received tulathromycin (2.5 mg/kg, SC), and calves in group 3 received isotonic saline (0.9% NaCl) solution (1 mL/45 kg, SC; control). On day 5, calves were inoculated with 10 mL of a solution containing H somni strain 7735 (1.6 × 10(9) CFUs/mL, intrabronchially; challenge). Calves were clinically evaluated on days 5 through 8 and euthanized on day 8. The lungs were grossly evaluated for evidence of pneumonia, and bronchial secretion samples underwent bacteriologic culture.

RESULTS

The mean clinical score for each group was significantly increased 12 hours after challenge, compared with that immediately before challenge, and was significantly lower for tildipirosin-treated calves on days 6, 7, and 8, compared with those for tulathromycin-treated and control calves. The mean percentage of lung consolidation for tildipirosin-treated calves was significantly lower than those for tulathromycin-treated and control calves. Histophilus somni was isolated from the bronchial secretions of some tulathromycin-treated and control calves but was not isolated from tildipirosin-treated calves.

CONCLUSIONS AND CLINICAL RELEVANCE

Results indicated that metaphylactic administration of tildipirosin to calves 5 days prior to H somni challenge prevented subsequent culture of the pathogen from bronchial secretions and was more effective in minimizing clinical disease and lung lesions than was metaphylactic administration of tulathromycin.