Low booster uptake in cancer patients despite health benefits.

Patients with cancer are at increased risk of death from COVID-19 and have reduced immune responses to SARS-CoV2 vaccines, necessitating regular boosters. We performed comprehensive chart reviews, surveys of patients attitudes, serology for SARS-CoV-2 antibodies and T-cell receptor (TCR) ß sequencing for cellular responses on a cohort of 982 cancer patients receiving active cancer therapy accrued between November-3-2020 and Mar-31-2023. We found that 92·3% of patients received the primer vaccine, 70·8% received one monovalent booster, but only 30·1% received a bivalent booster. Booster uptake was lower under age 50, and among African American or Hispanic patients. Nearly all patients seroconverted after 2+ booster vaccinations (>99%) and improved cellular responses, demonstrating that repeated boosters could overcome poor response to vaccination. Receipt of booster vaccinations was associated with a lower risk of all-cause mortality (HR=0·61, P=0·024). Booster uptake in high-risk cancer patients remains low and strategies to encourage booster uptake are needed. Highlights: COVID-19 booster vaccinations increase antibody levels and maintain T-cell responses against SARS-CoV-2 in patients receiving various anti-cancer therapiesBooster vaccinations reduced all-cause mortality in patientsA significant proportion of patients remain unboosted and strategies are needed to encourage patients to be up-to-date with vaccinations.

Successful autologous hematopoietic stem cell transplants using Salmonella positive products collected from asymptomatic donors.

BACKGROUND: Bacterial contamination of hematopoietic stem cell (HSC) products is most commonly due to normal skin flora. Salmonella in HSC products is rare, and to our knowledge safe administration of an autologous HSC product containing Salmonella has not been reported. STUDY DESIGN AND METHODS: We describe two patients undergoing autologous HSC transplant: peripheral blood HSC collection was performed by leukapheresis, and samples were cultured according to standard institutional protocol. Subsequent microorganism identification was performed using MALDI-TOF (Bruker Biotyper). Strain-relatedness was investigated by infrared spectroscopy using the IR Biotyper (Bruker). RESULTS: The patients were asymptomatic throughout the collection process; however, HSC products collected on two consecutive days from each patient were positive for Salmonella. Isolates from both cultures were further characterized as Salmonella enterica serovar Dublin by the local public health department. Antibiotic susceptibility testing revealed different sensitivity patterns for the two strains. IR Biotyper demonstrated significant discriminatory power among the clinically significant Salmonella enterica subspecies, serogroups B, C1, and D. The patient strains were similar as both belonged to Group D Salmonella enterica serovar Dublin but were not identical. The Salmonella positive autologous HSC products were infused to both patients following administration of empiric antibiotic therapy. Both patients successfully engrafted and did well. CONCLUSION: Salmonella is rarely seen in cellular therapy products and positivity may be the result of asymptomatic bacteremia at the time of collection. We present two instances of autologous HSC products containing Salmonella that were infused, along with prophylactic antimicrobial therapy without significant adverse clinical effects.

Longitudinal SARS-CoV-2 mRNA Vaccine-Induced Humoral Immune Responses in Patients with Cancer.

Longitudinal studies of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccine-induced immune responses in patients with cancer are needed to optimize clinical care. In a prospective cohort study of 366 (291 vaccinated) patients, we measured antibody levels [anti-spike (IgG-(S-RBD) and anti-nucleocapsid immunoglobulin] at three time points. Antibody level trajectories and frequency of breakthrough infections were evaluated by tumor type and timing of treatment relative to vaccination. IgG-(S-RBD) at peak response (median = 42 days after dose 2) was higher (P = 0.002) and remained higher after 4 to 6 months (P = 0.003) in patients receiving mRNA-1273 compared with BNT162b2. Patients with solid tumors attained higher peak levels (P = 0.001) and sustained levels after 4 to 6 months (P < 0.001) compared with those with hematologic malignancies. B-cell targeted treatment reduced peak (P = 0.001) and sustained antibody responses (P = 0.003). Solid tumor patients receiving immune checkpoint inhibitors before vaccination had lower sustained antibody levels than those who received treatment after vaccination (P = 0.043). Two (0.69%) vaccinated and one (1.9%) unvaccinated patient had severe COVID-19 illness during follow-up. Our study shows variation in sustained antibody responses across cancer populations receiving various therapeutic modalities, with important implications for vaccine booster timing and patient selection. SIGNIFICANCE: Long-term studies of immunogenicity of SARS-CoV-2 vaccines in patients with cancer are needed to inform evidence-based guidelines for booster vaccinations and to tailor sequence and timing of vaccinations to elicit improved humoral responses.

Treatment patterns and clinical outcomes of tyrosine kinase inhibitors in chronic-phase CML in clinical practice: 3-year European SIMPLICITY data.

OBJECTIVES: SIMPLICITY (NCT01244750) is an observational study of patients with chronic-phase chronic myeloid leukemia (CP-CML) in routine clinical practice receiving first-line tyrosine kinase inhibitors (TKIs). We evaluated TKI treatment changes and how switching affects clinical response in patients recruited in Europe with ≥3 years of follow-up. METHODS: The SIMPLICITY European cohort (France, Germany, Italy, the Netherlands, Russia, and Spain) included 431 patients. 370 (86%) were followed for ≥3 years. RESULTS: Proportions of patients experiencing treatment interruptions, TKI switching, and discontinuations decreased over 3 years' follow-up. Intolerance was a key driver for treatment changes. Complete cytogenetic response (CCyR) was achieved in 87.5% of patients switching TKI within 3 years of initiation vs 91.7% of non-switchers. Major molecular response (MMR) was achieved in 82.4% of switchers vs 92.9% of non-switchers. Over 3 years, not switching TKI was a strong predictor for achieving CCyR or MMR (both P < .05). Three-year survival remained high, irrespective of treatment changes (95.3% switchers, 96.4% non-switchers). CONCLUSIONS: European patients with CP-CML who do not switch TKI are more likely to achieve clinical response, while intolerance is a key driver for switching. Successful CML management may require careful selection of initial TKI, with early monitoring of response and intolerance.

Safety of bloodless autologous stem cell transplantation in Jehovah's Witness patients.

Due to the curative potential and improvement in progression-free survival (PFS), high-dose chemotherapy followed by autologous stem cell transplantation (ASCT) is considered the standard of care for several hematologic malignancies, such as multiple myeloma, and lymphomas. ASCT typically involves support with blood product transfusion. Thus, difficulties arise when Jehovah's Witness patients refuse blood transfusions. In order to demonstrate the safety of performing "bloodless" ASCT (BL-ASCT), we performed a retrospective analysis of 66 Jehovah's Witnesses patients who underwent BL-ASCT and 1114 non-Jehovah's Witness patients who underwent transfusion-supported ASCT (TF-ASCT) at Cedars-Sinai Medical Center between January 2000 and September 2018. Survival was compared between the two groups. Transplant-related complications, mortality, engraftment time, length of hospital stay, and number of ICU transfers were characterized for the BL-ASCT group. One year survival was found to be 87.9% for both groups (P = 0.92). In the BL-ASCT group, there was one death prior to the 30 days post transplant due to CNS hemorrhage, and one death prior to 100 days due to sepsis. Based on our data, BL-ASCT can be safely performed with appropriate supportive measures, and we encourage community oncologists to promptly refer JW patients for transplant evaluation when ASCT is indicated.

Ponatinib efficacy and safety in Philadelphia chromosome-positive leukemia: final 5-year results of the phase 2 PACE trial.

Ponatinib has potent activity against native and mutant BCR-ABL1, including BCR-ABL1T315I The pivotal phase 2 Ponatinib Ph+ ALL and CML Evaluation (PACE) trial evaluated efficacy and safety of ponatinib at a starting dose of 45 mg once daily in 449 patients with chronic myeloid leukemia (CML) or Philadelphia chromosome-positive acute lymphoblastic leukemia (ALL) resistant/intolerant to dasatinib or nilotinib, or with BCR-ABL1T315I This analysis focuses on chronic-phase CML (CP-CML) patients (n = 270) with 56.8-month median follow-up. Among 267 evaluable patients, 60%, 40%, and 24% achieved major cytogenetic response (MCyR), major molecular response (MMR), and 4.5-log molecular response, respectively. The probability of maintaining MCyR for 5 years was 82% among responders. Dose reductions were implemented in October 2013 to decrease the risk of arterial occlusive events (AOEs); ≥90% of CP-CML patients who had achieved MCyR or MMR maintained response 40 months after elective dose reductions. Estimated 5-year overall survival was 73%. In CP-CML patients, the most common treatment-emergent adverse events were rash (47%), abdominal pain (46%), thrombocytopenia (46%), headache (43%), dry skin (42%), and constipation (41%). The cumulative incidence of AOEs in CP-CML patients increased over time to 31%, while the exposure-adjusted incidence of new AOEs (15.8 and 4.9 per 100 patient-years in years 1 and 5, respectively) did not increase over time. These final PACE results demonstrate ponatinib provides durable and clinically meaningful responses, irrespective of dose reductions, in this population of heavily pretreated CP-CML patients. This trial was registered at www.clinicaltrials.gov as #NCT01207440.

Correction: Inhibition of IRE1α-driven pro-survival pathways is a promising therapeutic application in acute myeloid leukemia.

[This corrects the article DOI: 10.18632/oncotarget.7702.].

Long-term survival in patients treated with ruxolitinib for myelofibrosis: COMFORT-I and -II pooled analyses.

BACKGROUND: Myelofibrosis (MF) is associated with a variety of burdensome symptoms and reduced survival compared with age-/sex-matched controls. This analysis evaluated the long-term survival benefit with ruxolitinib, a Janus kinase (JAK)1/JAK2 inhibitor, in patients with intermediate-2 (int-2) or high-risk MF. METHODS: This was an exploratory analysis of 5-year data pooled from the phase 3 COMFORT-I and -II trials. In both trials, patients could cross over to ruxolitinib from the control group (COMFORT-I, placebo; COMFORT-II, best available therapy). All continuing patients in the control groups crossed over to ruxolitinib by the 3-year follow-up. Overall survival (OS; a secondary endpoint in both trials) was evaluated using pooled intent-to-treat data from patients randomized to ruxolitinib or the control groups. OS was also evaluated in subgroups stratified by baseline anemia and transfusion status at week 24. RESULTS: A total of 528 patients were included in this analysis; 301 were originally randomized to ruxolitinib (COMFORT-I, n = 155; COMFORT-II, n = 146) and 227 to control (n = 154 and n = 73, respectively). The risk of death was reduced by 30% among patients randomized to ruxolitinib compared with patients in the control group (median OS, 5.3 vs 3.8 years, respectively; hazard ratio [HR], 0.70 [95% CI, 0.54-0.91]; P = 0.0065). After correcting for crossover using a rank-preserving structural failure time (RPSFT) method, the OS advantage was more pronounced for patients who were originally randomized to ruxolitinib compared with patients who crossed over from control to ruxolitinib (median OS, 5.3 vs 2.3 years; HR [ruxolitinib vs RPSFT], 0.35 [95% CI, 0.23-0.59]). An analysis of OS censoring patients at the time of crossover also demonstrated that ruxolitinib prolonged OS compared with control (median OS, 5.3 vs 2.4 years; HR [ruxolitinib vs censored at crossover], 0.53 [95% CI, 0.36-0.78]; P = 0.0013). The survival benefit with ruxolitinib was observed irrespective of baseline anemia status or transfusion requirements at week 24. CONCLUSIONS: These findings support ruxolitinib treatment for patients with int-2 or high-risk MF, regardless of anemia or transfusion status. Further analyses will be important for exploring ruxolitinib earlier in the disease course to assess the effect on the natural history of MF. TRIAL REGISTRATION: ClinicalTrials.gov identifiers, NCT00952289 and NCT00934544 .

Long-term treatment with ruxolitinib for patients with myelofibrosis: 5-year update from the randomized, double-blind, placebo-controlled, phase 3 COMFORT-I trial.

BACKGROUND: The randomized, double-blind, placebo-controlled, phase 3 COMFORT-I trial evaluated the JAK1/JAK2 inhibitor ruxolitinib in patients with intermediate-2/high-risk myelofibrosis. The primary and planned 3-year analyses of COMFORT-I data demonstrated that ruxolitinib-the first myelofibrosis-approved therapy-reduced splenomegaly and prolonged overall survival versus placebo. Here, we present the final 5-year results. METHODS: Patients managed in Australia, Canada, and the USA were randomized centrally (interactive voice response system) 1:1 to oral ruxolitinib twice daily (15 or 20 mg per baseline platelet counts) or placebo. Investigators and patients were blinded to treatment. The secondary endpoints evaluated in this analysis were durability of a ≥35% reduction from baseline in spleen volume (spleen response) and overall survival, evaluated in the intent-to-treat population. Safety was evaluated in patients who received study treatment. RESULTS: Patients were randomized (September 2009-April 2010) to ruxolitinib (n = 155) or placebo (n = 154). At termination, 27.7% of ruxolitinib-randomized patients and 25.2% (28/111) who crossed over from placebo were on treatment; no patients remained on placebo. Patients randomized to ruxolitinib had a median spleen response duration of 168.3 weeks and prolonged median overall survival versus placebo (ruxolitinib group, not reached; placebo group, 200 weeks; HR, 0.69; 95% CI, 0.50-0.96; P = 0.025) despite the crossover to ruxolitinib. The ruxolitinib safety profile remained consistent with previous analyses. The most common new-onset all-grade nonhematologic adverse events starting <12 versus ≥48 months after ruxolitinib initiation were fatigue (29.0 vs 33.3%) and diarrhea (27.8 vs 14.6%). New-onset grade 3 or 4 anemia and thrombocytopenia both primarily occurred within the first 6 months, with no cases after 42 months. The most common treatment-emergent adverse event-related deaths in the ruxolitinib-randomized group were sepsis (2.6%), disease progression (1.9%), and pneumonia (1.9%). CONCLUSION: The final COMFORT-I results continue to support ruxolitinib as an effective treatment for patients with intermediate-2/high-risk MF. TRIAL REGISTRATION: ClinicalTrials.gov, NCT00952289.

Primary analysis of a phase II open-label trial of INCB039110, a selective JAK1 inhibitor, in patients with myelofibrosis.

Combined Janus kinase 1 (JAK1) and JAK2 inhibition therapy effectively reduces splenomegaly and symptom burden related to myelofibrosis but is associated with dose-dependent anemia and thrombocytopenia. In this open-label phase II study, we evaluated the efficacy and safety of three dose levels of INCB039110, a potent and selective oral JAK1 inhibitor, in patients with intermediate- or high-risk myelofibrosis and a platelet count ≥50×109/L. Of 10, 45, and 32 patients enrolled in the 100 mg twice-daily, 200 mg twice-daily, and 600 mg once-daily cohorts, respectively, 50.0%, 64.4%, and 68.8% completed week 24. A ≥50% reduction in total symptom score was achieved by 35.7% and 28.6% of patients in the 200 mg twice-daily cohort and 32.3% and 35.5% in the 600 mg once-daily cohort at week 12 (primary end point) and 24, respectively. By contrast, two patients (20%) in the 100 mg twice-daily cohort had ≥50% total symptom score reduction at weeks 12 and 24. For the 200 mg twice-daily and 600 mg once-daily cohorts, the median spleen volume reductions at week 12 were 14.2% and 17.4%, respectively. Furthermore, 21/39 (53.8%) patients who required red blood cell transfusions during the 12 weeks preceding treatment initiation achieved a ≥50% reduction in the number of red blood cell units transfused during study weeks 1-24. Only one patient discontinued for grade 3 thrombocytopenia. Non-hematologic adverse events were largely grade 1 or 2; the most common was fatigue. Treatment with INCB039110 resulted in clinically meaningful symptom relief, modest spleen volume reduction, and limited myelosuppression.

Inhibition of IRE1α-driven pro-survival pathways is a promising therapeutic application in acute myeloid leukemia.

Survival of cancer cells relies on the unfolded protein response (UPR) to resist stress triggered by the accumulation of misfolded proteins within the endoplasmic reticulum (ER). The IRE1α-XBP1 pathway, a key branch of the UPR, is activated in many cancers. Here, we show that the expression of both mature and spliced forms of XBP1 (XBP1s) is up-regulated in acute myeloid leukemia (AML) cell lines and AML patient samples. IRE1α RNase inhibitors [MKC-3946, 2-hydroxy-1-naphthaldehyde (HNA), STF-083010 and toyocamycin] blocked XBP1 mRNA splicing and exhibited cytotoxicity against AML cells. IRE1α inhibition induced caspase-dependent apoptosis and G1 cell cycle arrest at least partially by regulation of Bcl-2 family proteins, G1 phase controlling proteins (p21cip1, p27kip1 and cyclin D1), as well as chaperone proteins. Xbp1 deleted murine bone marrow cells were resistant to growth inhibition by IRE1α inhibitors. Combination of HNA with either bortezomib or AS2O3 was synergistic in AML cytotoxicity associated with induction of p-JNK and reduction of p-PI3K and p-MAPK. Inhibition of IRE1α RNase activity increased expression of many miRs in AML cells including miR-34a. Inhibition of miR-34a conferred cellular resistance to HNA. Our results strongly suggest that targeting IRE1α driven pro-survival pathways represent an exciting therapeutic approach for the treatment of AML.

A phase II multicenter rabbit anti-thymocyte globulin trial in patients with myelodysplastic syndromes identifying a novel model for response prediction.

Immune dysregulation is a mechanism contributing to ineffective hematopoiesis in a subset of myelodysplastic syndrome patients. We report the first US multicenter non-randomized, phase II trial examining the efficacy of rabbit(r)-anti-thymocyte globulin using 2.5 mg/kg/day administered daily for 4 doses. The primary end point was hematologic response; secondary end points included duration of response, time to response, time to progression, and tolerance. Nine (33%;95% confidence interval=17%-54%) of the 27 patients treated experienced durable hematologic improvement in an intent-to-treat analysis with a median time to response and median response duration of 75 and 245 days, respectively. While younger age is the most significant factor favoring equine(e)-anti-thymocyte globulin response, treatment outcome on this study was independent of age (P=0.499). A shorter duration between diagnosis and treatment showed a positive trend (P=0.18), but International Prognostic Scoring System score (P=0.150), karyotype (P=0.319), and age-adjusted bone marrow cellularity (P=0.369) were not associated with response classification. Since activated T-lymphocytes are the primary cellular target of anti-thymocyte globulin, a T-cell expression profiling was conducted in a cohort of 38 patients consisting of rabbit and equine-antithymocyte globulin-treated patients. A model containing disease duration, CD8 terminal memory T cells and T-cell proliferation-associated-antigen expression predicted response with the greatest accuracy using a leave-one-out cross validation approach. This profile categorized patients independent of other covariates, including treatment type and age using a leave-one-out-cross-validation approach (75.7%). Therefore, rabbit-anti-thymocyte globulin has hematologic remitting activity in myelodysplastic syndrome and a T-cell activation profile has potential utility classifying those who are more likely to respond (NCT00466843 clinicaltrials.gov).

Comparison of placebo and best available therapy for the treatment of myelofibrosis in the phase 3 COMFORT studies.

Prior to Janus kinase inhibitors, available therapies for myelofibrosis were generally supportive and did not improve survival. This analysis compares efficacy outcomes of patients with myelofibrosis in the control arms (placebo [n=154] and best available therapy [n=73]) from the two phase 3 COntrolled MyeloFibrosis study with ORal JAK inhibitor Treatment (COMFORT) studies. Spleen volume was assessed by magnetic resonance imaging/computed tomography at baseline and every 12 weeks through week 72; spleen length was assessed by palpation at each study visit. Health-related quality of life and symptoms were assessed using the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire-Core 30 Items at baseline and in weeks 4, 8, 12, 16 and 24 in COMFORT-I and in weeks 8, 16, 24 and 48 in COMFORT-II. The demographic and baseline characteristics were similar between the control arms of the two studies. One patient who received placebo and no patients who received best available therapy had a ≥35% reduction in spleen volume from baseline at week 24. At 24 weeks, neither placebo nor best available therapy had produced clinically meaningful changes in global quality of life or symptom scales. Non-hematologic adverse events were mostly grade 1/2; the most frequently reported adverse events in each group were abdominal pain, fatigue, peripheral edema and diarrhea. These data suggest that non-Janus kinase inhibitor therapies provide little improvement in splenomegaly, symptoms or quality of life as compared with placebo. Both COMFORT-I (NCT00952289) and COMFORT-II (NCT00934544) studies have been appropriately registered with clinicaltrials.gov.

Interim analysis of safety and efficacy of ruxolitinib in patients with myelofibrosis and low platelet counts.

BACKGROUND: Ruxolitinib, a Janus kinase 1 and 2 inhibitor, demonstrated improvements in spleen volume, symptoms, and survival over placebo and best available therapy in intermediate-2 or high-risk myelofibrosis patients with baseline platelet counts ≥100 × 109/L in phase III studies. The most common adverse events were dose-dependent anemia and thrombocytopenia, which were anticipated because thrombopoietin and erythropoietin signal through JAK2. These events were manageable, rarely leading to treatment discontinuation. Because approximately one-quarter of MF patients have platelet counts <100 × 109/L consequent to their disease, ruxolitinib was evaluated in this subset of patients using lower initial doses. Interim results of a phase II study of ruxolitinib in myelofibrosis patients with baseline platelet counts of 50-100 × 109/L are reported. METHODS: Ruxolitinib was initiated at a dose of 5 mg twice daily (BID), and doses could be increased by 5 mg once daily every 4 weeks to 10 mg BID if platelet counts remained adequate. Additional dosage increases required evidence of suboptimal efficacy. Assessments included measurement of spleen volume by MRI, MF symptoms by MF Symptom Assessment Form v2.0 Total Symptom Score [TSS]), Patient Global Impression of Change (PGIC); EORTC QLQ-C30, and safety/tolerability. RESULTS: By week 24, 62% of patients achieved stable doses ≥10 mg BID. Median reductions in spleen volume and TSS were 24.2% and 43.8%, respectively. Thrombocytopenia necessitating dose reductions and dose interruptions occurred in 12 and 8 patients, respectively, and occurred mainly in patients with baseline platelet counts ≤75 × 109/L. Seven patients experienced platelet count increases ≥15 × 109/L. Mean hemoglobin levels remained stable over the treatment period. Two patients discontinued for adverse events: 1 for grade 4 retroperitoneal hemorrhage secondary to multiple and suspected pre-existing renal artery aneurysms and 1 for grade 4 thrombocytopenia. CONCLUSIONS: Results suggest that a low starting dose of ruxolitinib with escalation to 10 mg BID may be appropriate in myelofibrosis patients with low platelet counts.

Efficacy, safety and survival with ruxolitinib in patients with myelofibrosis: results of a median 2-year follow-up of COMFORT-I.

COMFORT-I is a randomized, double-blind, placebo-controlled trial of the Janus kinase 1/Janus kinase 2 inhibitor ruxolitinib in 309 patients with intermediate-2 or high-risk myelofibrosis. This analysis of COMFORT-I describes the long-term efficacy and safety of ruxolitinib (median follow-up, 2 years). Spleen volume was measured by magnetic resonance imaging, and quality of life was evaluated using the EORTC QLQ-C30. Overall survival was determined according to randomized treatment group. At the time of this analysis, 100 of 155 patients randomized to ruxolitinib were still receiving treatment. All patients randomized to placebo crossed over to ruxolitinib or discontinued within 3 months of the primary analysis (median time to crossover, 41 weeks). Mean spleen volume reductions in the ruxolitinib group were 31.6% at week 24 and 34.9% at week 96; improvements in quality of life measures were also maintained. Improved survival was observed for ruxolitinib (n=27 deaths) versus placebo (n=41 deaths) (hazard ratio=0.58; 95% confidence interval: 0.36, 0.95; P=0.03). The incidence of new-onset grade 3 or 4 anemia and thrombocytopenia decreased over time to levels observed in patients receiving placebo. These data indicate that ruxolitinib treatment provides durable reductions in spleen volume and improvements in quality of life and suggest a continued survival advantage for ruxolitinib over placebo.

Somatic SETBP1 mutations in myeloid malignancies.

Here we report whole-exome sequencing of individuals with various myeloid malignancies and identify recurrent somatic mutations in SETBP1, consistent with a recent report on atypical chronic myeloid leukemia (aCML). Closely positioned somatic SETBP1 mutations encoding changes in Asp868, Ser869, Gly870, Ile871 and Asp880, which match germline mutations in Schinzel-Giedion syndrome (SGS), were detected in 17% of secondary acute myeloid leukemias (sAML) and 15% of chronic myelomonocytic leukemia (CMML) cases. These results from deep sequencing demonstrate a higher mutational detection rate than reported with conventional sequencing methodology. Mutant cases were associated with advanced age and monosomy 7/deletion 7q (-7/del(7q)) constituting poor prognostic factors. Analysis of serially collected samples indicated that SETBP1 mutations were acquired during leukemic evolution. Transduction with mutant Setbp1 led to the immortalization of mouse myeloid progenitors that showed enhanced proliferative capacity compared to cells transduced with wild-type Setbp1. Somatic mutations of SETBP1 seem to cause gain of function, are associated with myeloid leukemic transformation and convey poor prognosis in myelodysplastic syndromes (MDS) and CMML.

The clinical benefit of ruxolitinib across patient subgroups: analysis of a placebo-controlled, Phase III study in patients with myelofibrosis.

Myelofibrosis (MF) patients can present with a wide spectrum of disease characteristics. We analysed the consistency of ruxolitinib efficacy across patient subgroups in the COntrolled MyeloFibrosis Study With ORal JAK Inhibitor Treatment (COMFORT-I,) a double-blind trial, where patients with intermediate-2 or high-risk MF were randomized to twice-daily oral ruxolitinib (n = 155) or placebo (n = 154). Subgroups analysed included MF subtype (primary, post-polycythaemia vera, post-essential thrombocythaemia), age (≤65, > 65 years), International Prognostic Scoring System risk group, baseline Eastern Cooperative Oncology Group performance status (0, 1, ≥2), JAK2 V617F mutation (positive, negative), baseline haemoglobin level (≥100, <100 g/l), baseline platelet count (100-200 × 10(9)/l, >200 × 10(9)/l), baseline palpable spleen size (≤10, >10 cm), and baseline quartile of spleen volume and Total Symptom Score (TSS; Q1 = lowest, Q4 = highest). Mean percentage change from baseline to week 24 in spleen volume and TSS were calculated for ruxolitinib and placebo in each subgroup. Overall survival was estimated by Kaplan-Meier method according to original randomization group. In ruxolitinib-treated patients, reductions in spleen volume and TSS and evidence of improved survival relative to placebo across subgroups were consistent with those seen in the COMFORT-I population, confirming that ruxolitinib is an effective therapy for the spectrum of MF patients studied in COMFORT-I.

Expansion of effector memory regulatory T cells represents a novel prognostic factor in lower risk myelodysplastic syndrome.

Myelodysplastic syndromes are premalignant diseases characterized by cytopenias, myeloid dysplasia, immune dysregulation with association to autoimmunity, and variable risk for acute myeloid leukemia transformation. Studies of FOXP3(+) regulatory T cells (Tregs) indicate that the number and/or activation state may influence cancer progression in these patients. Focusing on patients with a lower risk for leukemia transformation, 18 (34.6%) of 52 patients studied displayed an altered Treg compartment compared with age-matched controls. Delineation of unique Treg subsets revealed that an increase in the absolute number of CD4(+)FOXP3(+)CD25(+)CD127(low)CD45RA(-)CD27(-) Tregs (effector memory Tregs [Treg(EM)]) was significantly associated with anemia (p = 0.046), reduced hemoglobin (p = 0.038), and blast counts ≥5% (p = 0.006). In healthy donors, this Treg(EM) population constitutes only 2% of all Tregs (one to six Tregs per microliter) in peripheral blood but, when isolated, exhibit greater suppressive activity in vitro. With a median follow-up of 3.1 y (range 2.7-4.9 y) from sample acquisition, increased numbers of Treg(EM) cells proved to have independent prognostic importance in survival estimates, suggesting that enumeration of this Treg subset may be a more reliable indicator of immunological escape than FOXP3(+) T cells as a whole. Based on multivariate analyses, Treg(EM) impacted survival independently from myeloblast characteristics, cytopenias, karyotype, and comorbidities. Based on these findings, Treg(EM) cell expansion may be synonymous with human Treg activation and indicate microenvironmental changes conducive to transformation in myelodysplastic syndromes.

Phase 2 study of the lenalidomide and azacitidine combination in patients with higher-risk myelodysplastic syndromes.

Lenalidomide and azacitidine each have activity in myelodysplastic syndromes (MDS) patients, where both microenvironment and cell-regulatory mechanisms contribute to disease pathogenesis. The objective of this multicenter, phase 2 expansion trial was to determine the efficacy and safety of combination therapy with azacitidine (75 mg/m(2)/d for 5 days) and lenalidomide (10 mg/d for 21 days; 28-day cycle) in patients with higher-risk MDS. Among 36 patients enrolled (18 phase 1, 18 phase 2), median age was 68 years (range, 47-78 years) and follow-up was 12 months (range, 3-55 years). IPSS categories included intermediate-1 (n = 5 patients with excess blasts), intermediate-2 (20), and high (11). Common grade 3/4 nonhematologic adverse events included febrile neutropenia (22% of patients), other infection (11%), pulmonary (11%), cardiac (11%), constitutional (11%), and dermatologic (11%). The overall response rate (per modified MDS International Working Group criteria) was 72%: 16 patients (44%) achieved a complete response (CR), and 10 (28%) had hematologic improvement. Median CR duration was 17+ months (range, 3-39+); median overall survival was 37+ months (range, 7-55+) for CR patients, and 13.6 months for the entire cohort (range, 3-55). TET2/DNMT3A/IDH1/2 mutational status was associated with response in a limited number of patients. The lenalidomide/azacitidine combination is well-tolerated and highly active in treating greater-risk MDS.

A double-blind, placebo-controlled trial of ruxolitinib for myelofibrosis.

BACKGROUND: Ruxolitinib, a selective inhibitor of Janus kinase (JAK) 1 and 2, has clinically significant activity in myelofibrosis. METHODS: In this double-blind trial, we randomly assigned patients with intermediate-2 or high-risk myelofibrosis to twice-daily oral ruxolitinib (155 patients) or placebo (154 patients). The primary end point was the proportion of patients with a reduction in spleen volume of 35% or more at 24 weeks, assessed by means of magnetic resonance imaging. Secondary end points included the durability of response, changes in symptom burden (assessed by the total symptom score), and overall survival. RESULTS: The primary end point was reached in 41.9% of patients in the ruxolitinib group as compared with 0.7% in the placebo group (P<0.001). A reduction in spleen volume was maintained in patients who received ruxolitinib; 67.0% of the patients with a response had the response for 48 weeks or more. There was an improvement of 50% or more in the total symptom score at 24 weeks in 45.9% of patients who received ruxolitinib as compared with 5.3% of patients who received placebo (P<0.001). Thirteen deaths occurred in the ruxolitinib group as compared with 24 deaths in the placebo group (hazard ratio, 0.50; 95% confidence interval, 0.25 to 0.98; P=0.04). The rate of discontinuation of the study drug because of adverse events was 11.0% in the ruxolitinib group and 10.6% in the placebo group. Among patients who received ruxolitinib, anemia and thrombocytopenia were the most common adverse events, but they rarely led to discontinuation of the drug (in one patient for each event). Two patients had transformation to acute myeloid leukemia; both were in the ruxolitinib group. CONCLUSIONS: Ruxolitinib, as compared with placebo, provided significant clinical benefits in patients with myelofibrosis by reducing spleen size, ameliorating debilitating myelofibrosis-related symptoms, and improving overall survival. These benefits came at the cost of more frequent anemia and thrombocytopenia in the early part of the treatment period. (Funded by Incyte; COMFORT-I ClinicalTrials.gov number, NCT00952289.).