Multiple site place-of-care manufactured anti-CD19 CAR-T cells induce high remission rates in B-cell malignancy patients

Chimeric antigen receptor (CAR) T cells targeting the CD19 antigen are effective in treating adults and children with B-cell malignancies. Place-of-care manufacturing may improve performance and accessibility by obviating the need to cryopreserve and transport cells to centralized facilities. Here we develop an anti-CD19 CAR (CAR19) comprised of the 4-1BB co-stimulatory and TNFRSF19 transmembrane domains, showing anti-tumor efficacy in an in vivo xenograft lymphoma model. CAR19 T cells are manufactured under current good manufacturing practices (cGMP) at two disparate clinical sites, Moscow (Russia) and Cleveland (USA). The CAR19 T-cells is used to treat patients with relapsed/refractory pediatric B-cell Acute Lymphocytic Leukemia (ALL; n = 31) or adult B-cell Lymphoma (NHL; n = 23) in two independently conducted phase I clinical trials with safety as the primary outcome (NCT03467256 and NCT03434769, respectively). Probability of measurable residual disease-negative remission was also a primary outcome in the ALL study. Secondary outcomes include complete remission (CR) rates, overall survival and median duration of response. CR rates are 89% (ALL) and 73% (NHL). After a median follow-up of 17 months, one-year survival rate of ALL complete responders is 79.2% (95%CI 64.5‒97.2%) and median duration of response is 10.2 months. For NHL complete responders one-year survival is 92.9%, and median duration of response has not been reached. Place-of-care manufacturing produces consistent CAR-T cell products at multiple sites that are effective for the treatment of patients with B-cell malignancies.

Strategies to address the challenges associated with product manufacturing can improve chimeric antigen receptor (CAR) cell–based therapeutics. Here the authors report the results of two clinical trials in patients with B-cell malignancies, showing that place-of-care manufacturing has a low production failure rate with CD19-directed CAR-T cell products inducing high remission rates.

Phase 1 trial of anti-CD19 chimeric antigen receptor T (CAR-T) cells with tumor necrosis alfa receptor superfamily 19 (TNFRSF19) transmembrane domain

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Background: AntiCD19 CAR-T cells have shown encouraging anti-lymphoma activity. Decreasing the time from apheresis to CAR-T infusion can make this therapy available to pts with rapid progression. We present the interim results of a phase I clinical trial using on-site CAR-T manufacture. Methods: Adult pts with r/r CD19+ B cell lymphomas who failed ≥ 2 lines of therapy were enrolled. Autologous T cells were transduced with a lentiviral vector (Lentigen Technology, Inc,LTG1563) encoding an antiCD19 binding motif, CD8 linker and TNFRSF19 transmembrane region, and 4-lBB/CD3z domains. GMP-compliant manufacture was done using CliniMACS Prodigy, in a 12-day culture. Dose levels were 0.5, 1 and 2 x 106 CAR-T cells/kg. Lymphodepletion was done with cyclophosphamide (60mg/kg x 1) and fludarabine (25mg/m2/d x 3). Results: 7 pts (4 women, 3 men) were enrolled. Median age was 60y [range 43-69]. Diagnoses were DLBCL (n = 3) PMBCL, follicular lymphoma (FL), transformed FL, and transformed lymphoplasmacytic lymphoma; with a median of 4 previous treatments. Six pts had symptomatic refractory disease. CAR-T cell product manufacture was successful in all pts. Mean transduction rate was 44% [range 29-57]. CAR-T cell doses were 0.5 x 106/kg (n = 3) and 1 x 106/kg (n = 4). Median apheresis to infusion time was 13 days [range 13–20], 5 products were infused fresh. CAR-T persistence based on vector sequence, peaked in peripheral blood MNCs between days 14-21. Five pts are evaluable for safety. CRS grade 1 - 2 (Lee) occurred in 4 pts; with 3 requiring treatment. Grade 4 CRES (CARTOX-10) occurred in 1 pt, with resolution after corticosteroids; considered a DLT as it lasted more than 72 hours. No treatment-related mortality has occurred. 4/5 evaluable pts have achieved complete response. One pt did not respond and died. After a median follow up 3 months, all responding pts are alive and 1 relapsed 6 mo after treatment. Conclusions: Second generation antiCD19 CAR-T cells with TNFRS19 transmembrane domain have clinical activity against refractory NHL. Short manufacture time achieved by local CAR-T cell manufacture with the CliniMACS Prodigy enables treatment of a very high risk NHL population. Clinical trial information: NCT03434769.

Polidocanol (Lauromacrogol 400) has anti-angiogenic effects in vitro and in vivo

OBJECTIVE

Polidocanol is the most frequently used sclerosant for sclerotherapy all around the world. Our experimental research aims to find out the angiogenic effects of Polidocanol.

MATERIALS AND METHODS

Angiogenic activity of polidocanol was examined in vivo in the chick chorioallantoic membrane (CAM) model, cell viability assay (human umbilical vein endothelial cells - HUVECs) and in vitro tube formation assay of HUVECs.

RESULTS

In CAM assay, a significant decrease on CAM vessel growth was observed after the application of polidocanol solutions. Vessel growth inhibition was strongly dose-dependent. There was a cytotoxic effect on HUVECs in the presence of polidocanol observed with MTT assay (p < 0.05). In the tube formation assay, statistically significant decrease in tube formation was observed in polidocanol group. It was found that polidocanol had an anti-angiogenic effect (p < 0.05). The results provide evidence that polidocanol decreases angiogenesis and has a cytotoxic effect on ECs.

CONCLUSIONS

These results provide evidence that Polidocanol (lauromacrogol 400) have strong anti-angiogenic effects in vitro and in vivo. Further researches needed to reveal early and long-term effects of polidocanol in the human vascular system and new treatment approach as an anti-angiogenic therapy.

Abstract P2-01-04: A method for comprehensive genomic analysis of cell free DNA

Circulating tumor DNA (ctDNA) is released from tumor tissue into the blood, carries tumor specific genetic alterations, and can be analyzed through noninvasive "liquid biopsy" approaches to identify genetic alterations in cancer patients. Liquid biopsies offer a considerable advantage as they may eliminate the need for invasive tissue biopsies and allow for the detection of alterations in multiple metastatic lesions throughout the course of therapy. However, the fraction of ctDNA obtained from a blood sample is often very low (&lt;1.0%) and can be difficult to detect. Additionally, most methods to evaluate circulating tumor DNA (ctDNA) interrogate single hot spot mutations or few genetic alterations. The next generation of ctDNA assays must interrogate multiple gene regions from a single sample with high precision and accuracy and need to evaluate all forms of actionable genomic alterations including point mutations, amplifications, and translocations. To address these issues, we have developed a ctDNA approach called PlasmaSelect to detect somatic sequence mutations, amplifications and translocations at low allele frequencies in the circulation of cancer patients. Utilizing digital genomic approaches, PlasmaSelect achieves high sensitivity and specificity while interrogating &gt;250,000 nucleotides spanning 63 well-established cancer genes. In addition to sequence mutations in the entire coding region of 18 genes and the exons of 40 genes that are frequently mutated in cancer, PlasmaSelect also performs a comprehensive genomic analysis of amplifications in 57 genes and translocations in 10 genes significant in cancer tumorigenesis. To evaluate the PlasmaSelect approach, we performed dilution series using tumor-derived DNA, containing well-characterized somatic mutations, in the presence of wild-type DNA. PlasmaSelect was able to detect genetic alterations with high specificity and a lower level of detection of 0.10% for sequence mutations and translocations, as well as a focal amplification of ERBB2 with a lower level of detection of 0.20%. We evaluated the clinical utility of PlasmaSelect for detection of genetic alterations in the plasma and matched tissue biopsy specimens from late stage cancer patients. These analyses demonstrated high concordance between the somatic sequence mutations, amplifications, and translocations identified in the tumor sample and those identified directly in the plasma, including alterations in both driver genes as well as those related to acquired resistance to targeted therapies. PlasmaSelect provides a non-invasive platform to enable liquid biopsy detection of clinically relevant genetic alterations across a large number of genomic loci.

Citation Format: Parpart-Li S, Angiuoli SV, Chesnick B, Galens K, Jones S, Kadan M, Kann L, Lytle K, Murphy D, Nesselbush M, Phallen J, Riley D, Shukla M, Zhang T, Husain H, Velculescu V, Diaz, Jr LA, Sausen M. A method for comprehensive genomic analysis of cell free DNA. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P2-01-04.

Sedoanalgesia for cardioversion: comparison of alfentanil, remifentanil and fentanyl combined with propofol and midazolam: a prospective, randomized, double-blind study

OBJECTIVE

Electrical cardioversion (EC) is a short but painful procedure to restore sinus rhythm. The aim of this study is to compare the effect of fentanyl, remifentanil and alfentanil in association with propofol and midazolam for elective EC.

PATIENTS AND METHODS

Ninety-nine patients older than 18-years, American Society of Anesthesiologists I/II/III grades undergoing elective EC were randomized into 3 groups. All patients received 2 mg midazolam and propofol (0.5 mg/kg). Group A received alfentanil (5 µg/kg i.v. bolus), Group F received fentanyl (0.5 µg/kg i.v. bolus) and Group R received remifentanil (0.25 µg/kg i.v. bolus). Hemodynamics and respiratory variables [Heart rate (HR), systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP), SpO2, respiratory rate (RR)], and Modified Aldrete recovery score (MARS) were assessed at six different time points (baseline, right after EC, and 3rd min, 5th min, 10th min, 30th min following EC). Also, induction times (time to reach RSS to 5) and recovery times (time to reach MARS to 8) were recorded. The incidence of respiratory depression, bradycardia, hypotension and adverse effects were also recorded.

RESULTS

Hemodynamic variables were similar in all groups. SpO2 values in Group R were significantly lower at 3rd min (p = 0.005). Induction and recovery times were longest in Group F. There were significant differences at 3rd, 5th and 10th minute MARS values between groups. The incidence of hypotension and bradycardia were similar in all groups (p > 0.05) but respiratory depression was higher in Group R (p = 0.047).

CONCLUSIONS

Propofol alfentanil combination has more beneficial advantages in their rapid onset, early recovery time and less respiratory depression than remifentanil and fentanyl.

In vitro effect of sodium nitrite on platelet aggregation in human platelet rich plasma--preliminary report

OBJECTIVE

The role of nitrates and nitric oxide on platelet functions has obtained an increasing attention with respect to their potential effects on cardiovascular disorders. In this study we aimed to analyze the effect of sodium nitrite on platelet functions in human platelets.

PATIENTS AND METHODS

This in vitro study was designed to show the effect of sodium nitrite on platelet functions in seven healthy volunteers. Blood samples were centrifuged to prepare platelet rich plasma and platelet poor plasma. Platelet rich plasma was diluted with the platelet poor plasma to have a final count of 300,000 ± 25,000 platelets. Platelet rich plasma was incubated with six different increasing doses (from 10 μM to 5 mM) of sodium nitrite for 1 hour at 37°C. Then stimulating agents including collagen (3 μg ml-1), adenosine diphosphate (10 μM), and epinephrine (10 μM) were added to the cuvette. Changes in light transmission were observed for 10 minutes. In addition spontaneous aggregation were performed in control group with all aggregating agents separately.

RESULTS

Effect of sodium nitrite on agonist-induced platelet aggregation depends on the concentration of sodium nitrite. Compared with control group, agonist-induced platelet aggregations were significantly suppressed by sodium nitrite at the concentration of 5, 1.0 and 0.5 mM.

CONCLUSIONS

Our results suggested that sodium nitrite has inhibitory effects in vitro on platelet aggregation in a dose-dependent manner.

New probing and warm-wash-out technique improves early patency rates in arteriovenous fistula surgery

OBJECTIVE

Arteriovenous fistulas (AVFs) are commonly used during hemodialysis. Early failure of AVFs is quite common with incidence of 43% to 63%. In this study we aimed to describe a novel approach to AVF surgery for improving early patency rates.

PATIENTS AND METHODS

Patients were divided into two groups according to use of probing and warm-wash-out technique. Group I consisted of 31 patients with additional probing technique. Group II consisted of 32 patients without additional maneuver. End-to-side anastomosis were used to all patients. Technical success was defined as having palpation of a thrill on fistula. Flow rates of draining vein was measured at 1st hour, 24th hour, 1st week and 3rd week of surgery.

SURGICAL TECHNIQUE

Classical maneuvers were performed until end of the anastomosis. At this time, vein lumen was washed by low-dosed heparinized warm fluid, with assistance of a simple catheter.

RESULTS

Technical success was similar in both groups at 1st hour and 24th hour, while there were significantly differences between groups at 1st week (p = 0.042) and 3rd week (p = 0.05) assessments. Flow rates were also measured significantly higher in Group I at 1st hour (p = 0.011) and 24th hour (p = 0.016). Flow rates were almost similar in two groups at 1st and 3rd weeks but overall success rate was higher in Group I comparing with Group II (96.8% vs. 81.3%, respectively, p = 0.05).

CONCLUSIONS

Probing and warm-wash out technique will simply increase the surgical success and flow rate of draining vein.

Comparison of angiogenic and proliferative effects of three commonly used agents for pulmonary artery hypertension (sildenafil, iloprost, bosentan): is angiogenesis always beneficial?

OBJECTIVE

Pulmonary artery hypertension (PAH) is devastating disease that has very serious outcomes. Dysregulated angiogenesis is one of the main responsible courses in pathophysiology of disease. Our experimental research intends to find out and compare the angiogenic effects of medications used sildenafil, iloprost, and bosentan in the treatment of PAH.

MATERIALS AND METHODS

This study was performed in Department of Biochemistry and Cancer and Stem Cell Research Laboratory of our institutes between August and October 2014. Angiogenic activity of sildenafil, iloprost, and bosentan were examined in vivo in chick chorioallantoic membrane (CAM) model and in vitro tube formation assay of human umbilical vein endothelial cells (HUVECs). Proliferative activity of these three agents was also determined through 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay on HUVECs.

RESULTS

In CAM assay, when compared to the control and drug groups, treatment with sildenafil solutions resulted in a significant dose-dependent increase (budding, sprouting, extravasation) on CAM vessel growth. While there was no significant proliferative effect with iloprost and bosentan, presence of sildenafil caused a statistically significant proliferation on HUVECs following 24 and 48 h incubation (p < 0.05) compared to the control group. Comparing the tube length/area ratio values, there was statistically significant increase in sildenafil group with respect to the other 2 groups (p < 0.05). Iloprost and bosentan did not show a significant effect.

CONCLUSIONS

The results provide evidence that sildenafil but not iloprost and bosentan induces angiogenesis in vitro and in vivo. Dysregulated angiogenesis, as an important pathophysiological part in the progression of PAH, may be triggered by the chronic ingestion of sildenafil in the long treatment period and may cause negative effects.

Local sympathetic stimulation not only have local effects in patients with Raynaud's phenomenon

OBJECTIVE

Many other organs and system can be affected in the course of Primary Raynaud's Phenomenon (RP). Simultaneously increased vasospasm in the pulmonary vascular bed may likely affect the pulmonary function. Therefore, we investigated the effect of Raynaud's phenomenon on the respiratory functions in this study.

PATIENTS AND METHODS

Between March 2014 and December 2014, 30 patients with the diagnosis of PRP more than two years and 32 age-sex matched healthy controls were enrolled into this study. Cold stimulation test (CST) was performed. Pulmonary function test were performed following 30 minutes after CST and spirometric measurements were calculated.

RESULTS

There were no statistically significant differences between two groups regarding their demographic and clinical data. Mean duration of symptoms from onset to present was 3.01 ± 1.05 years. Patients with Primary RP had significantly lower FVC and higher FEV1/FVC values compared to the control groups (p = 0.015 and p=0.045, respectively).

CONCLUSIONS

We found that statistically significant decrease of FVC values in patients with Primary RP compared to the healthy controls could be a impaired innervation of pulmonary system and a predictor of pulmonary vasospasm and/or pulmonary Raynaud's phenomenon, which may develop in future periods.

Generation of an adenovirus vector lacking E1, e2a, E3, and all of E4 except open reading frame 3

Toxicity and immunity associated with adenovirus backbone gene expression is an important hurdle to overcome for successful gene therapy. Recent efforts to improve adenovirus vectors for in vivo use have focused on the sequential deletion of essential early genes. Adenovirus vectors have been constructed with the E1 gene deleted and with this deletion in combination with an E2a, E2b, or E4 deletion. We report here a novel vector (Av4orf3nBg) lacking E1, E2a, and all of E4 except open reading frame 3 (ORF3) and expressing a beta-galactosidase reporter gene. This vector was generated by transfection of a plasmid carrying the full-length vector sequence into A30.S8 cells that express E1 and E2a but not E4. Production was subsequently performed in an E1-, E2a-, and E4-complementing cell line. We demonstrated with C57BL/6 mice that the Av4orf3nBg vector effected gene transfer with an efficiency comparable to that of the Av3nBg (wild-type E4) vector but that the former exhibited a higher level of beta-galactosidase expression. This observation suggests that E4 ORF3 alone is able to enhance RNA levels from the beta-galactosidase gene when the Rous sarcoma virus promoter is used to drive transgene expression in the mouse liver. In addition, we observed less liver toxicity in mice injected with the Av4orf3nBg vector than those injected with the Av3nBg vector at a comparable DNA copy number per cell. This study suggests that the additional deletion of E4 in an E1 and E2a deletion background may be beneficial in decreasing immunogenicity and improving safety and toxicity profiles, as well as increasing transgene capacity and expression for liver-directed gene therapy.

Factors affecting retroviral vector function and structural integrity

Recombinant retroviruses are widely used for gene transfer into eukaryotic cells and exhibit significant potential for human gene therapy. Despite the utility of retroviral vectors, their design is still essentially empirical. We have constructed a series of reciprocal, double-gene vectors to compare the dual expression of beta-galactosidase (beta-gal) and neomycin phosphotransferase (neor) in a retroviral delivery system. The first gene of the pair was driven by the viral LTR promoter and the internal gene was regulated by either the SV40 virus early promoter or the cytomegalovirus (CMV) major late promoter. Clones of vector producer cells were isolated either by G418 selection for expression of neor, or by fluorescence-activated cell sorting for expression of beta-gal, and the activity of both genes was evaluated. In general, vectors using the SV40 promoter performed better than those with the CMV promoter, regardless of whether the selected gene was regulated by the LTR or the internal promoter. Southern analysis of clones indicated that loss of beta-gal gene function was related to significant rearrangements and deletions in vector structure. We also found that the arrangement of genes within the vector was important. When beta-gal preceded neor, gene expression and vector stability were markedly enhanced relative to vectors containing these genes in the inverse order.