No abstract

Despite advances in the treatment of HIV infection with ART, elucidating strategies to overcome HIV persistence, including blockade of viral reservoir establishment, maintenance, and expansion, remains a challenge. T cell homeostasis is a major driver of HIV persistence. Cytokines involved in regulating homeostasis of memory T cells, the major hub of the HIV reservoir, trigger the Jak-STAT pathway. We evaluated the ability of tofacitinib and ruxolitinib, two FDA-approved Jak inhibitors, to block seeding and maintenance of the HIV reservoir in vitro. We provide direct demonstration for involvement of the Jak-STAT pathway in HIV persistence in vivo, ex vivo, and in vitro; pSTAT5 strongly correlates with increased levels of integrated viral DNA in vivo, and in vitro Jak inhibitors reduce the frequency of CD4+ T cells harboring integrated HIV DNA. We show that Jak inhibitors block viral production from infected cells, inhibit γ-C receptor cytokine (IL-15)-induced viral reactivation from latent stores thereby preventing transmission of infectious particles to bystander activated T cells. These results show that dysregulation of the Jak-STAT pathway is associated with viral persistence in vivo, and that Jak inhibitors target key events downstream of γ-C cytokine (IL-2, IL-7 and IL-15) ligation to their receptors, impacting the magnitude of the HIV reservoir in all memory CD4 T cell subsets in vitro and ex vivo. Jak inhibitors represent a therapeutic modality to prevent key events of T cell activation that regulate HIV persistence and together, specific, potent blockade of these events may be integrated to future curative strategies.

Daratumumab is a human IgG1k monoclonal antibody targeting the CD38 surface antigen on plasma cells with proven efficacy in multiple myeloma. While biology of clonal plasma cells in AL amyloidosis is distinct from myeloma, clonal plasma cells in AL amyloidosis express surface CD38, providing a rationale for using daratumumab. Infusion-related reactions (IR) of 48% were reported in patients who had daratumumab as monotherapy for relapsed multiple myeloma. Therefore, we designed a clinical trial to study tolerability of daratumumab in those with relapsed AL amyloidosis (clinicaltrials.gov identifier: NCT02841033). The primary objective was to determine the safety and tolerability of infusion of daratumumab, with respect to IR. The secondary objectives were to assess hematologic response, clinical response and time to next treatment. Accrual began in April 2017. Patients with AL amyloidosis after ≥1 prior therapy, and involvement of at least 1 vital organ , eGFR of >20 mL/min, AST/ALT < 3xULN, NT-proBNP ≤8500 pg/mL, LVEF ≥30%, FEV1 ≥50% in patients with COPD or chronic smokers, and ECOG performance status of <3, received daratumumab at 16 mg/kg IV infusion weekly for weeks 1-8, followed by every 2 weeks for weeks 9-24 and every 4 weeks thereafter until progression or unacceptable toxicity, for up to 24 months. The first infusion of daratumumab was given in 1000 mL, the second infusion in 500 mL if no grade 1 or greater reactions occurred, and subsequent doses were administered in 500 mL of saline. All patients received acetaminophen, diphenhydramine, loratadine, famotidine, montelukast and methylprednisolone (100 mg for first 2 infusions and 60 mg thereafter) 30-60 mins prior to infusion. Ondansetron was added after development of grade 1 nausea/vomiting in the first 2 patients. Diphenhydramine, famotidine and methylprednisolone (40 mg) were also administered 2 hrs after start of infusion during the first 2 infusions even if there was no reaction. Methylprednisolone 20 mg (or its equivalent) and montelukast were given 24 and 48 hrs after start of infusion for the first 2 infusions and then it was optional. All patients received prophylaxis with acyclovir. At data cut-off (July 1, 2018) 24 patients were screened and 21 were enrolled. The median age was 65 (range, 42-84), and the median of prior therapies was 2 (range, 1-6): 14 (58.3%) had received SCT, 9 (37.5%) immunomodulatory agents, and 16 (66.6%) proteasome inhibitors. Eleven (52.3%) patients were refractory to prior therapy and the median time from last therapy was 9 months (range, 1-180). The median time from diagnosis to enrollment was 57 months. The median number of organ systems involved was 2 (range, 1-5): 11 (52.3%) had involvement of ≥2 organ systems, 18 (85.7%) had cardiac biomarker stage II or III disease. Median NT-proBNP level was 1346 pg/mL (range, 32-3962) and urine protein excretion was 0.4 g/24 h (range, 0-10.1), while median dFLC was 87.8 mg/L (range, 2.9-328.4). Now, 18 patients are on study and 375 infusions have been completed. The median of infusions received per patient is 19 (range, 3-27). Two patients were removed after developing progression of plasma cell dyscrasia after 2 and 9 cycles and 1 patient was removed by patient choice after 8 cycles. No patient experienced a grade 3-4 IR. Four (19%) patients experienced grade 1 nausea and vomiting during first infusion, which resolved after an antiemetic. The median time of first infusion was 7 hrs and 2nd infusion was 4 hrs 29 mins. Grade 3/4 adverse events were noted in 16 (76%) patients. Respiratory illnesses were experienced by 14 (66.6%), 3 (14%) of these were grade 3 events (Influenza A, Rhino/Enteroviral infection, PCP). Six (28.5%) patients were noted to be iron deficient and required parenteral iron infusion. Hematologic responses were rapid as shown in figure. Hematologic CR and VGPR were achieved by 84.2% (16/19), 85.7% (12/14) and 100% (6/6) patients at 3 months, 6 months and 12 months respectively. Renal response was evident in 37.5% (3/8) and cardiac response was evident in 40% (4/10) at 6 months following initiation of treatment. Daratumumab infusion is well tolerated in patients with relapsed AL amyloidosis when administered with appropriate supportive care. Infusion-related reactions were minimal and not comparable to reported incidence in myeloma. A rapid hematologic response after 1 dose of daratumumab in patients with AL amyloidosis is seen. Figure. Figure. Disclosures Sloan: Stemline Therapeutics: Consultancy.

Objectives:The diagnosis of hematologic malignancies integrates multiple diagnostic and clinical disciplines. Historically, targeted (single-analyte) genetic testing has been used as reflex to initial prescreening by other diagnostic modalities including flow cytometry, anatomic pathology, and clinical cytogenetics. Given the wide range of mutations associated with hematologic malignancies a DNA/RNA-based NGS panel can provide a more effective and economical approach to comprehensive testing of patients as an initial, tier-1 screen. | 179 LEVY Et aL.Methods: Using a cohort of 380 patients, we performed clinical validation of a gene panel designed to assess 40 genes (DNA), and 29 fusion driver genes with over 600 gene fusion partners (RNA), including sample exchange data across three clinical laboratories, and correlation with cytogenetic testing results. Results:The clinical validation of this technology demonstrated that its accuracy, sensitivity, and specificity are comparable to the majority of targeted single-gene approaches, while assessment of the initial patient cohort data demonstrated a high diagnostic yield of 50.5%.Conclusions: Implementation of a tier-1 NGS-based protocol for gene panel screening provides a comprehensive alternative to targeted molecular testing in patients with suspected hematologic malignancies, with increased diagnostic yield, scalability, reproducibility, and cost effectiveness, making it ideally suited for implementation in clinical laboratories.

Summary Next‐generation sequencing (NGS) increasingly influences diagnosis, prognosis and management of myelodysplastic syndrome (MDS). In addition to marrow morphology and flow cytometry, our institution performs cytogenetics (CG) and NGS‐based testing routinely in patients with suspected MDS. We evaluated the relative value of NGS in the assessment of patients with suspected MDS. We initially compared the diagnostic and prognostic information derived from CG and NGS in 134 patients. NGS enhanced the diagnostic yield compared to CG for clonal myeloid disorders (sensitivity 77% vs. 42·2%; specificity 90·2% vs. 78%; positive predictive value 92·8% vs. 76%; and negative predictive value 70·8% vs. 45·5%). The identification of poor prognosis mutations by NGS altered risk category in 27/39 (69·2%) patients with MDS with good/intermediate risk CG. Subsequently, we prospectively evaluated 70 patients with suspected MDS using an ‘NGS‐first approach’ with CG restricted to samples with morphological abnormalities. We rarely identified mutations or CG abnormalities in patients without dysplastic features. NGS has a superior diagnostic performance compared to CG in patients with suspected MDS. We estimate that by using an ‘NGS‐first approach’ we could reduce karyotyping by approximately 30%.