Citations

Abstract The standard of care for CLL is to treat only patients with obvious clinical progression because earlier intervention is not of proven benefit. The discovery of more accurate prognostic markers for CLL could change that paradigm. The predictors of more aggressive disease include 17p13 deletion (17p13−), 11q22-3 deletion (11q22−), unmutated (UM) immunoglobulin heavy-chain variable region (IgVH), and expression of ZAP-70 and CD38. In addition, monoclonal antibody (MoAb) therapies provide effective treatment with less toxicity than chemotherapy and are likely to be most efficacious in early stage CLL. The combination of alemtuzumab (ALEM) and rituximab (RIT) is of interest because of non-overlapping mechanisms of action. ALEM is also effective therapy for patients with defects in the p53 apoptotic pathway that are more resistance to purine analogue therapy. We tested the hypothesis that MoAb therapy with ALEM and RIT will eliminate/greatly decrease the high risk clone characterized by 17p13−, 11q22−, or UM IgVH plus either ZAP70+ or CD38+, in early stage CLL. Methods This trial will enroll a maximum of 30 patients and be considered promising if ≥ 19 patients respond. All patients with previously untreated CLL (Rai stage 0 −II) not meeting NCI-WG 1996 treatment criteria and with a high risk CLL clone were evaluated for enrollment. Treatment duration was 30 days (subcutaneous ALEM dose escalation, 3 mg - 10 mg - 30 mg on days 1–3) then 30 mg Monday, Wednesday and Friday for 4 weeks. RIT (375 mg/m2/dose IV x 4) was administered weekly staring on day 8. All patients received PCP and herpes virus prophylaxis and had CMV viral DNA testing for 7 months. Response was evaluated using NCI-WG 1996 criteria and minimal residual disease (MRD) was measured in peripheral blood using sensitive flow cytometry (1:104) for CD19+/CD5+/CD79b− lymphocytes. Results Since January 2005, 17 patients have been enrolled and the interim analyses are for the first 11 patients accrued. Median age was 62 years (29 – 75) with 6 males and 5 females. The qualifying high risk features were 17p13− (n = 4), 11q22− (n = 3), and UM IgVH + CD38+ +/− ZAP-70+ (n = 4). Median time from diagnosis to treatment was 11 months (2–72). Clinical stage (Rai) was 0 in 3 patients, I in 5 patients and II in 3 patients. Median absolute lymphocyte count was 25.6 x 109/L (15.9 – 81.8), Hgb 14.4 g/dL (12 – 15.8), and platelet count 171 x 109/L (125 – 312). Two patients had serious adverse reactions requiring intervention (CMV reactivation responsive to treatment; febrile drug reaction to sulfamethoxazole/trimethoprim). Grade 3–4 adverse reactions not requiring interventions were leukopenia (n = 4), neutropenia (n = 2), anemia (n = 1), elevated ALT (n = 1), and skin reaction to ALEM (n =1). There were no “first dose” reactions. All patients responded to therapy with 5 CR (4 of these MRD negative), 3 nodular PR, and 3 PR. Median duration of response has not yet been reached at median follow up of 11.7 months (6.5 – 14.9). Patients with a MRD negative CR had recurrence of detectable MRD at 120 – 210 days after completing therapy but all remain in CR. One patient died off study of complications of a myeloablative allogeneic transplant for progressive CLL. Discussion ALEM and RIT is effective and tolerable therapy for early stage high risk CLL. All patients responded with 36% achieving a MRD negative CR but serial MRD assays showed that the CLL clone was not deleted. This promising, treatment requires further improvement.

Abstract Background: Follicular lymphoma is a B-cell malignancy in which tumor-immune system interactions have the potential to profoundly influence malignant cell growth. Cytotoxic T lymphocyte antigen 4 (CTLA-4) is a negative regulator of T cell activation that can serve to dampen anti-tumor immune responses. Administration of blocking anti-CTLA-4 monoclonal antibodies has been shown to improve host resistance to immunogenic tumors and amplify the anti-tumor effects of cancer vaccines in a variety of mouse tumor models. Recently, the anti-CTLA-4 antibody ipilimumab (MDX-010) has been shown to have significant clinical activity against melanoma, prostate, and ovarian cancers, with clinical responses associated with autoimmune events. Methods: We have therefore initiated a phase I/II trial of ipilimumab, a blocking fully human monoclonal antibody to CTLA-4, in patients with relapsed or refractory follicular lymphoma (grade 1 or 2). Enrollment is stratified into 2 cohorts, with half of patients required to be previously treated with a lymphoma vaccine (idiotype or other). It is hypothesized that previously vaccinated subjects are more likely to have anti-lymphoma T cells amenable to activation by an anti-CTLA-4 antibody. Study objectives include characterization of drug safety, immunologic activity and potential clinical efficacy. Treatment consists of MDX-010 at 3 mg/kg, then monthly at 1 mg/kg x 3, with plans to escalate to 3 mg/kg monthly x 4 if tolerated. Results: To date, 12 patients have been treated and accrual to the first dose level has been completed. All patients were previously treated and the median number of prior treatment regimens was 2 (range 1–4). Eight patients had previously received rituximab and 6 patients had received prior anti-idiotype vaccines. Nine patients have completed therapy with ipilimumab and 3 patients are still receiving treatment. Ipilimumab was generally well tolerated and the most common adverse events attributed to ipilimumab in the first 9 patients include diarrhea (grade 3–3 patients, grade 1–1 patient), abdominal pain (grade 2–4, grade 1–2), anorexia (grade 2-1, grade 1 – 2), fatigue (grade 2 -2, grade 1–3, and neutropenia (grade 3-1, grade 1– 2). Among 9 patients evaluable for clinical response, 1 previously vaccinated patient had partial regression of multiple abdominal nodes, ongoing at 10+ months. T cell proliferative responses to the recall antigens tetanus toxoid and keyhole limpet hemocycanin (in idiotype-vaccinated cases) were measured pre- and post-ipilimumab. In 3 of 5 cases tested, including the patient with a clinical response, T cell proliferation to KLH and/or tetanus was significantly increased (>2-fold) one month after initiation of ipilimumab, implying expansion and/or activation of the memory T cell pool. Conclusions: Blockade of CTLA-4 signaling using ipilimumab is well tolerated at the dose used thus far in this ongoing study and has anti-tumor activity in patients with follicular B-cell lymphoma. Further evaluation of the efficacy of ipilimumab at this and higher doses is therefore warranted.

Abstract Small lymphocytic lymphoma (SLL) is an incurable indolent lymphoma, and there are relatively few prognostic biomarkers for this important NHL subtype. We evaluated the hypothesis that inherited variability in cytokine and immune-related genes was associated with overall survival in SLL. We genotyped 73 SNPs in 44 candidate genes in 140 SLL patients aged 20–70 years who participated in a population-based case-control study conducted from 1998–2000 through the Surveillance, Epidemiology, and End Results (SEER) cancer registries in Detroit, Seattle, Iowa, and Los Angeles. DNA was extracted from a venous blood sample or mouthwash buccal cell sample. All genotyping was conducted at the National Cancer Institute Core Genotyping Facility using the Taqman platform. Histology, stage, presence of B-symptoms, first course of therapy, date of last follow-up, and vital status were derived from linkage to registry databases at each study site in the spring of 2005. Cox proportional hazards analysis was used to estimate the hazard ratio (HR) and 95% confidence interval for the association between individual SNPs and overall survival, adjusted for age, demographic and clinical factors. Multiple simultaneous modeling strategies were used to identify the best summary multi-SNP risk score to predict survival. At last follow-up, there were 45 deaths in 140 patients (32%). The median follow-up of the 95 surviving patients was 58 months (range 24–75 months). In multivariate modeling, SNPs in IL13 (rs1800925; HRCC=2.36, 1.24–4.49), IL7R (rs1494555; HRGG =2.20, 0.84–5.76), and TNF-alpha (rs1800630; HRAC/AA=1.73, 0.95–3.17) were the strongest and most robust predictors of survival. Two or more deleterious genotypes from these three SNPs increased the risk of death (HR=2.2, 1.2–4.1) compared with one or fewer deleterious genotypes (p=0.009). Three groups (low, intermediate, and high risk) were defined by combining the SNP score and a clinical/demographic score. The 5-year Kaplan-Meier survival estimates for these groups were 85%, 65%, and 11%, respectively. Compared to patients with a low risk score, patients with intermediate (HR=2.5, 1.2–5.1) or high (HR=11, 4.3–27.7) risk scores had poorer overall survival (p=3.9 x 10−8). Our preliminary results suggest that SNPs in IL13, IL7R, and TNF-alpha alone and in combination predict overall survival in SLL, lending support to the hypothesis that host genetic background is a promising class of prognostic biomarkers in SLL.

Abstract Background: CLL is a disease of the elderly and at least half of the patients requiring therapy are over age 70. While chemoimmunotherapy (CIT) has dramatically improved response rates in patients with CLL, some CIT regimens are not well tolerated by elderly patients. The MD Anderson group has reported that the fludarabine, cyclophosphamide, rituximab (FCR) regimen is not well tolerated in individuals ≥age 70 (Ferrajoli Leuk Lymph 46:S86). The German CLL Study Group has postulated that physiologic health is more important than chronologic age and have conducted a trial of FCR that permits enrollment of patients ≥age 70 provided they have a creatinine clearance (CrCl) ≥70 and good performance status (PS). While this approach expands the number of individuals who can receive CIT, it still excludes large percentages of CLL patients in need of treatment. Here, we examine how age, CrCl, and PS relate to the efficacy and tolerability of the pentostatin, cyclophosphamide, and rituximab (PCR) regimen. Methods: We treated 64 previously untreated CLL patients meeting NCI 96 criteria for treatment with pentostatin (2mg/m2), cyclophosphamide (600 mg/m2) and rituximab (375mg/m2) (Kay ASH 2006). All medications were administered on day 1 of every 3 week cycle with the intent of administering 6 cycles. We measured ECOG PS at study entry and used age, weight, and baseline creatinine to calculate the CrCl of all patients at study entry using the Cockroft-Gault equation. Results: Eighteen of 64 patients (28%) were ≥age 70. Although individuals ≥age 70 were more likely to have a dose delay of >1 week at some point during the trial (7% vs. 28%; p=0.03), there was no difference in the average number of cycles administered, the number of patients requiring dose reductions, or the number of patients with grade 3/4 hematologic toxicity, infectious complications, or other non-hematologic toxicity. No difference in OR (93% vs 83%; p=0.34) or CR (41% vs. 39%; p=0.86) was observed between patients <age 70 compared to those ≥70. We next evaluated whether CrCl related to the efficacy and tolerability of PCR. 25 patients (39%) had a CrCl<70, including 15 (23%) with a CrCl<60 and 5 (8%) with CrCl<50. Although individuals with CrCl<70 were more likely to have a dose reduction (5% vs. 24%; p=0.05), there was no difference in the average number of cycles administered, the number of patients requiring a dose delay, or the number of patients with grade 3/4 hematologic toxicity, infectious complications, or other non-hematologic toxicity. No difference in OR (89% vs 92%; p=1.0) or CR (45% vs. 36%; p=0.60) was observed between patients with CrCl≥70 and those with CrCl<70. We next evaluated how PS related to the efficacy and tolerability. 34 patients (53%) were PS 0 and 30 (47%) were PS≥1. This analysis suggested PCR was well tolerated among those with PS≥1. Again no difference in the OR or CR was observed between patients with PS 0 and those with PS≥1. Conclusions: In this phase II clinical trial, the PCR regimen was well tolerated by patients ≥age70, those with higher PS, and the 25 individuals with CrCl≤70 (range 34–67). The efficacy of PCR was also not significantly affected by age, renal function, or performance status. These findings suggest the PCR regimen may be superior to the FCR regimen for elderly patients and those with decreased renal function.

Abstract DLBCL is a curable subtype of non-Hodgkin lymphoma, although a significant number of patients do not achieve a remission or they relapse with conventional chemotherapy. While clinical variables (e.g., IPI), tumor (somatic) genetic alterations, and gene expression profiling have all been shown to predict outcome, there remains a need for additional prognostic biomarkers. One understudied class of biomarkers is host genetic background. We evaluated the hypothesis that germline variability in 73 SNPs from 44 candidate immune genes was associated with overall survival in DLBCL. We addressed this hypothesis in 365 DLBCL patients aged 20–70 years who participated in a population-based case-control study conducted from 1998–2000 (prior to the use of R-CHOP) through the Surveillance, Epidemiology, and End Results (SEER) cancer registries in Detroit, Seattle, Iowa, and Los Angeles. Germline DNA was extracted from a venous blood sample or mouthwash buccal cell sample, which was collected a median of 4.8 months after diagnosis in this population-based study. All genotyping was conducted at the National Cancer Institute Core Genotyping Facility using the Taqman platform, and was successful in over 95% of the DNA samples for the SNPs evaluated. Histology, stage, presence of B-symptoms, first course of therapy, date of last follow-up, and vital status were derived from linkage to registry databases at each study site in the spring of 2005. Cox proportional hazards analysis was used to evaluate the association between individual SNPs, adjusted for age, demographic and clinical factors. Parallel modeling strategies were used to identify the best summary multi-SNP risk score to predict survival. At a median follow-up of 56 months (range, 27-78 months) for surviving patients, there were 96 deaths in 365 patients (26%). In multivariate modeling, SNPs in IL1A (rs1800587; HRCT/TT=1.90, 1.26–2.87), IL6 (rs1800795; HRGG=1.48, 0.99–2.23), IL-10 (rs1800896; HRAG/GG=1.48, 0.91–2.38), and IFNGR2 (rs2070385; HRAG/GG=1.35, 0.86–2.11) were the strongest and most robust predictors of overall survival. A summary score of the number of deleterious genotypes from these four genes in combination with clinical and demographic variables was strongly associated with survival (p=9.3 x 10−12); Kaplan-Meier 5-year survival estimates for low, intermediate, and high risk patients were 89%, 68%, and 47% respectively. In conclusion, host genetic background as measured by germline polymorphisms in immune genes including IL1A, IL6, IL10, and IFNGR2 were associated with overall survival in DLBCL after accounting for clinical and demographic factors. These promising results require confirmation and need further evaluation in patients treated with R-CHOP in conjunction with tumor and other prognostic biomarkers.

Abstract Background: The prognosis of patients with early Rai and Binet stage CLL is variable. Recently developed prognostic tests (mutation status, ZAP-70, chromosome evaluation by FISH) require significant technologic expertise and are not available worldwide to most patients with CLL. Smudge cells are ruptured CLL cells appearing on a blood smear. Using a proteomic approach, we recently discovered that the cytoskeletal protein vimentin is expressed at higher levels in CLL cells with unmutated IgVH and that vimentin expression is a marker of poor prognosis in early stage CLL (Blood, 2005;106:707). Hypothesis: Since vimentin plays an important role in the cytoskeleton and lymphocyte rigidity, we hypothesized that smudge cell formation is inversely correlated with vimentin expression and that the percentage of smudge cells may predict prognosis in CLL. Methods: We blindly reviewed the blood smears archived at the time of diagnosis of patients with untreated, early stage CLL. A total of 200 lymphocytes and smudge cells were counted per slide and results reported as percentage of total lymphocytes (intact and smudged). The percentage of smudge cells was correlated with vimentin expression measured by flow cytometry, IgVH mutation status, time to treatment (TTT), and survival. Results: Blood smears of 75 patients were reviewed. The median percentage of smudge cells was 27% (range, 4–72%). The percentage of smudge cells did not correlate with lymphocytosis (r=0.04, p=0.73) and did not change overtime for serial evaluations for individual patients (p=0.61). The percentage of smudge cells appeared to correlate inversely with vimentin expression (r = − 0.627; p = 0.0017). The percentage of smudge cells was higher in patients with mutated IgVH than in patients with unmutated IgVH (median 31% vs. median 13%, p=0.02). The percentage of smudge cells as a continuous variable correlated with both a prolonged TTT (p=0.0023) and overall survival (p=0.04). Patients with less than 30% smudge cells had a median TTT of 72.7 months. The median TTT in patients with ≥30% smudge cells was not reached (p=0.0011), Figure 1. Conclusion: A lower percentage of smudge cells is associated with unmutated IgVH status and with worse clinical outcome in early stage CLL. The percentage of smudge cells does not vary based on the magnitude of the lymphocytosis, but is patient specific and remains constant over time. Evaluation of the percentage of smudge cells on blood smears could be a universally available prognostic test for patients with early stage CLL. Figure Figure

Abstract Background: Patients with early stage myeloma are typically observed without therapy until symptomatic disease occurs. We have reported early results of therapy with single-agent thalidomide as initial therapy for early stage multiple myeloma in an attempt to delay progression to symptomatic disease (Leukemia2003;17:775–9). We now report the long-term results of this phase II trial. Methods: Thirty-one patients with smoldering or indolent multiple myeloma were enrolled between April 1999–March 2002. All pts had bone marrow (BM) plasma cells >=10% and measurable disease defined as serum monoclonal (M) protein >=2gm/dL and/or urine M protein >=400mg/24 hours. Two patients were deemed ineligible because they were found to have received prior therapy for myeloma and were excluded from analysis. Thalidomide was initiated at a dose of 200 mg/day and increased as tolerated by 200 mg/day every 2 weeks to a maximum dose of 800 mg/day. The dose of thalidomide was decreased as needed to minimize toxicity. Treatment was continued until disease progression or serious toxicity, except for patients achieving less than a minor response (<25% paraprotein reduction) to therapy in whom therapy was stopped at one year. Response was defined as a decrease in serum and urine monoclonal (M) protein by 50% or higher. If the serum M protein was unmeasurable, a 90% or higher decrease in urine M protein was required. Responses need to be confirmed at least 4 weeks apart. Results: Ten patients (34%) had indolent myeloma, including 4 patients with lytic bone lesions, 3 patients with anemia (Hb <11gm/dL), and 3 patients with both anemia and lytic bone lesions. Median follow up of living patients is 5.6 years (range, 4.0–7.1 years). Of the twenty-nine eligible patients, ten (34%) had a partial response to therapy with at least 50% or greater reduction in serum and urine monoclonal (M) protein. Three patients are still on study and receiving therapy. The remaining have gone off-study: seven patients (27%)had progressive disease while on therapy; other reasons for ending study treatment included completed therapy per protocol (2 pts), patient refusal (2pts), toxicity (8 pts), alternate treatment (3 pts), other medical problems (1 pt), died on study (1 pt), and other (2 pts). The median time to progression (TTP) was 3.2 years (95% CI 2.1–5.6 yrs). Median progression free survival (PFS) was 3.0 yrs (95% CI 2.0–5.1 yrs). Median overall survival has not been reached; 5 year survival rate by the Kaplan Meier method is 60%. Major grade 3–4 non-hematologic adverse events at any time during therapy were noted in 34% of patients; this includes 14% with grade 4 toxicity. Grade 3–4 toxicities occurring in more than one patient include neuropathy (2 pts) and sinus bradycardia (2 pts). Conclusions: Thalidomide has activity in asymptomatic myeloma. This approach must be further tested in randomized trials to determine if the survival estimates are superior to observation. Given the activity of thalidomide, trials are also needed with lenalidomide.

Abstract Chronic Lymphocytic Leukemia (CLL) is primarily characterized by the presence of leukemic B lymphocytes resistant to the process of apoptosis. Causes for this resistance include aberrant expression of multiple anti-apoptotic proteins, perhaps including Tcl-1 (1). Tcl-1 is expressed during normal development of both B and T cells and activates Akt to provide a survival signal through phosphorylation and inactivation of apoptotic pathway components. Overexpression of Tcl-1 in the B cells of transgenic mice results in a B-cell leukemia phenotype typical of human CLL, suggesting a primary role for Tcl-1 in CLL tumorigenesis. A recent report showed that Tcl-1 protein expression in CLL cells correlated with other biological parameters, but no data were available as to its clinical relevance (2). We therefore examined Tcl-1 expression in relation to clinical outcome using 51 peripheral blood mononuclear cell samples from a Phase II clinical trial testing the combination of pentostatin, cyclophosphamide, and rituximab in previously untreated CLL patients (Kay et al., ASH 2006). Tcl-1 protein expression was measured by immunoblot using GAPDH as a normalization control across lanes and lysate from a single Tcl-1 transgenic mouse spleen as a normalization control across immunoblots. All samples were run at least in duplicate and digital quantitation was performed using a ChemiDoc instrument (BioRad). Tcl-1 expression in patient cells was calculated in comparison to Tcl-1 expression in the mouse lysate, arbitrarily set to 1.0. Data were analyzed as a continuous measure as well as by specific cutoffs. Higher Tcl-1 expression was associated with failure to achieve a minimal residual disease-negative state after treatment. Specifically, Tcl-1 expression (measured as a continuous variable) was associated with residual disease measured by post-treatment CD5+/CD19+ cell percentages (continuous variable as well as dichotomized by cutpoint of 1.0% for CD5+/CD19+; p=0.03 for both comparisons). For the dichotomized Tcl-1 expression with the cutpoint of 0.275 (second tertile), this variable was marginally significantly associated with whether or not post-treatment CD5+/CD19+ was less than 1.0%. Using this same cutoff, there was also a suggestion that patients with reduced Tcl-1 were more likely to achieve a complete response. Finally, progression-free survival was shorter in patients with increased Tcl-1 expression, although these data did not reach statistical significance in this sample set. Tcl-1 < 0.275 Tcl-1≥ 0.275 p value CD5/CD19≥ 1% 15 10 0.046 CD5/CD19 < 1% 16 2 CR 17 3 0.064 No CR 18 13 Median PFS (mos.) 36.5 17.1 0.137 Statistically significant associations with other parameters including Rai stage, IgVH mutation status, ZAP-70 expression, CD38 expression, and interphase cytogenetics categories were not detected in this sample set. These data further support the clinical relevance of the Tcl-1 mouse model to human CLL, and provide preliminary evidence that Tcl-1 protein expression correlates with clinical outcome of CLL patients treated with chemoimmunotherapy. If validated in larger studies, Tcl-1 expression may serve as a novel prognostic factor.

Abstract BACKGROUND: B-Chronic Lymphocytic Leukemia (CLL) is still uncurable but very powerful new tools are available with the use of chemoimmunotherapy (CIT). Purine nucleoside-based regimens that incorporate rituximab have generated very high levels of overall responses (OR) with significant percentage of those complete responses (CR) in previously untreated CLL. Here we report and update our experience with a phase 2 pentostatin-based CIT regimen for previously untreated CLL as conducted at 2 medical centers. We also studied the association of outcome based on risk stratification parameters and achievement of minimal residual disease. METHODS: Building on prior work of pentostatin in CLL by us (Kay ASH, 2004) and others, we initiated a trial of combined pentostatin (P)(2 mg/m2), cyclophosphamide (C)(600 mg/m2) and rituximab (R)(375 mg/m2) for symptomatic, previously untreated patients (n=65). This PCR regimen is given on a 21-day, 6-cycle schedule. However, the initial cycle of treatment uses thrice weekly rituximab as described by us earlier. In brief, this was rituximab at 100 mg/m2 on day 1, 375 mg/m2 on days 3 and 5 of the first week only. Prophylactic Sulfamethoxazole/Trimethoprim and Acyclovir were given to all patients for 1 year starting on the first cycle of therapy with PCR. All patients were risk stratified using CD38, ZAP-70, immunoglobulin heavy chain variable region gene (IgVH) and FISH panel assessments at entry. RESULTS: These patients were characterized as mostly in high-risk categories. Of 64 evaluable patients, 34 (53%) were high Rai risk (stage 3–4), 71% were non mutated for the IgVH gene, 34% were CD38+ and 34% were ZAP-70+. Thirty patients (52%) had one FISH anomaly, and 21 (36%) had complex FISH defects. Thirty-eight patients (58%) had grade 3+ hematologic toxicity but minimal transfusion needs, and no major infections. NCI Working Group Criteria Responses occurred in 58 (91%) with 26 (41%) complete responses (CR), 14 (22%) nodular partial responses (nodular PR), and 18 (28%) partial responses (PR) patients. Outcome for all 64 patients demonstrates a median progression-free survival of 32.6 months. Importantly, no high risk factor (i.e., age, FISH, IgVH status, CD38+, ZAP-70+) except for del (17p) defect (n=3) precluded attaining a CR or NPR. In contrast, we found this regimen was equally effective in young vs. elderly (>70 yrs) patients and in del(11)(q22.3) vs. other favorable prognostic FISH factors. Examination of outcome among CR and nodular PR patients for PFS by flow cytometry status (negative vs. positive, i.e., ≤ 1 % CD5+/CD19+ vs. ≥ 1 % CD5+/CD19+) demonstrated improvement in progression free survival for patients who attained flow cytometry negativity (p = 0.009). Conclusion: This novel regimen of pentostatin, cyclophosphamide and rituximab for previously untreated CLL demonstrated significant clinical activity despite poor risk-based prognoses with minimal toxicity in terms of bone marrow suppression and/or infections. The additional feature of this approach is the ability to have durable responses for all age groups and even CLL patients with a del(11)(q22.3).

Abstract Background: Myeloma remains incurable due to a stem cell/proliferative component that responds poorly to standard treatments. We have shown that aberrant IL-1beta stimulates the generation of paracrine IL-6, a central myeloma growth factor. A Phase II trial was completed using IL-1 receptor antagonist (IL-1Ra/Anakinra), which inhibits paracrine IL-6 production, and low dose Dexamethasone (Dex), which decreases IL-1 levels through myeloma cell apoptosis, in patients with SMM/IMM. SMM/IMM patients are most likely to benefit from anti-cytokine therapy in order to delay/prevent the development of active myeloma. Methods: Patients that had ≥ 10% bone marrow plasma cells and/or an IgG or IgA M-spike ≥ 3 g/dL and did not require immediate chemotherapy were eligible. All patients received 100 mg of IL-1Ra SQ qd for 6 months unless clinical progression occurred. Non-progressors were allowed to continue on therapy with IL-1Ra alone. Low dose Dex (20 mg qweek) was added after 6 months of IL-1Ra or for evidence of clinical progression; the dose was adjusted based on response/toxicity. Results: To investigate the effects of IL-1Ra and Dex alone and in combination in vitro, we co-cultured IL-1beta transduced +/− myeloma cells with stromal cells +/− dexamethasone, IL-1Ra, or both for 48 hours and quantitated the percent apoptotic cells by flow cytometry and IL-6 production by ELISA. The results showed that: 1) IL-1Ra was superior to Dex at inhibition of IL-6 but caused no myeloma apoptosis; 2) Dex induced apoptosis was inhibited by IL-6 3) Dex and IL-1Ra combined induced maximal IL-6 inhibition and apoptosis of myeloma cells. In the clinical trial, data were available on 47 patients; smoldering (79%) / indolent (21%). All patients received IL-1Ra initially and 20/47 subsequently received IL-1Ra/Dex. Seven patients had a decrease in the plasma cell labeling index (PCLI), a marker of cell proliferation, on IL-1Ra alone which paralleled a decrease in the high sensitivity C-reactive protein (CRP). Interestingly, in one patient treated with Dex alone for 6 months, Dex induced a decrease in the M-protein and IL-1 levels, however, the PCLI and CRP values increased. The IL-1Ra/Dex combination has resulted in stability of disease in the majority of the 47 patients; 28 continue on therapy with a median overall progression-free survival (PFS) of 37.5 months. Four of the 47 pts achieved a minor response (MR) with IL-1Ra alone, and an additional 6 pts achieved a MR/PR after addition of dex. The continuous measure of % reduction in CRP was significantly associated with time to progression (p=0.02). Similarly, those patients who had a >5% decrease in serum M protein also had a longer PFS (p<0.001). Of note, 2 patients with high PCLI values of 6.4 and 3.0, characteristic of poor prognosis, responded with a reduction in the PCLI values and continue on combination therapy for 3 and 1.5 years, respectively with stable disease. Conclusion: Agents such as IL-1Ra that specifically inhibit paracrine IL-6 production are more effective at targeting the proliferative component than apoptosis inducing agents such as Dex; the combination may be especially useful in patients that have an elevated PCLI at presentation.