Gertz, Morie A.

Abstract AMD3100, a CXCR4 receptor antagonist, has been studied as a stem cell mobilization agent for the purpose of autologous stem cell transplantation (ASCT) in hematologic malignancies. Lymphocyte subset analysis of peripheral blood in patients treated with AMD3100 has been studied in healthy volunteers. To date, no reports exist describing the lymphocyte subsets of the autograft in patients undergoing AMD3100 stem cell mobilization for the purposes of ASCT in non-Hodgkin lymphoma (NHL). Considering our prior work demonstrating the significant impact of autograft lymphocyte content on clinical outcomes of patients undergoing ASCT for NHL we set out to profile autograft lymphocyte subsets of patients undergoing mobilization with AMD3100. Using flow cytometry, we analyzed aliquots of apheresis products in 7 patients with NHL undergoing AHSCT who received AMD3100 in addition to G-CSF as a part of their mobilization regimen. These results were compared to 29 patients with NHL who had undergone stem cell mobilization with G-CSF alone. There were no significant differences between these two groups of patients in terms of sex, age, performance status, histology, LDH, and number of pretransplant chemotherapeutic regimens. CD34+ cells collected at apheresis did not differ significantly between the groups. However, compared with G-CSF alone, patients that received AMD3100 had an approximate 5-fold increase in CD4+ cells (0.62 x 109 cells/kg vs. 0.12 x 109 cells/kg, p = 0.0004), a 3.5-fold increase in the absolute number of autograft CD3+ cells (1.21 x 109 cells/kg vs. 0.33 x 109 cells/kg, p = 0.0017), and a 2.5-fold increase in CD8+ cells (0.48 x 109 cells/kg vs 0.19 x 109 cells/kg, p = 0.215). A significant increase was also noted in CD4+25+ cell compartment (0.17 x 109 cells/kg vs. 0.006 x 109 cells/kg, p = 0.0001). No significant difference was noted in the absolute number of autograft CD16+56+ NK cells. Finally, an increase in the autograft total absolute lymphocyte count (41.6 x 109 cells/kg vs. 2.88 x 109 cells/kg, p < 0.001) as well as peripheral blood absolute lymphocyte count at day 15 after AHSCT was observed in those patients who had received AMD3100 (0.79 x 109 cells/kg vs. 0.58 x 109 cells/kg, p = 0.04). The increased lymphocyte content of the autograft (total and subset) would suggest the potential of positive impact on clinical outcomes in patients mobilized with AMD3100. Indeed, none of the patients who received AMD3100 had relapsed disease at one year post-transplant (although two of these patients are currently 9 months and 11 months post-transplant respectively), whereas 10 of the 29 control patients had relapsed disease at one year. Further studies are necessary to confirm these observations and ascertain their clinical significance.

Abstract Background: While the therapeutic armamentarium for plasma cell disorders have expanded recently with introduction of thalidomide, lenalidomide and bortezomib, these diseases are still incurable and more agents are needed. We have previously demonstrated expression of CD 52 on plasma cells in MM, MGUS and AL amyloidosis. Based on this data we conducted a Phase II Study of Campath (Alemtuzumab; Monoclonal Anti-CD52 Antibody) in Primary Systemic Amyloidosis and Relapsed or Refractory Multiple Myeloma. Methods: The study was an IRB approved, Phase II protocol, with a two stage design and interim analysis at 14 patients, to assess the efficacy and toxicity of Alemtuzumab. The regimen involved a dose escalation during week one (Day I 3 mg SQ; Day II 10 mg SQ; Day III 30 mg SQ; then 30 mg SQ three times a week for a planned total of 17 additional weeks). All patients received concurrent Co-Trimoxazole, Fluconazole and Valacyclovir prophylaxis. The planned accrual was 32 patients. Results: A total of 14 patients were accrued, 8 patients with MM and 6 patients with AL. There were 8 females and 6 males in the study. The median age was 62 years (range: 50–78) years. The patients were heavily pretreated with the median number of treatments being 4. There were 5 grade 3–4 toxicities (CMV viremia (2 pts), skin rash (2 pts), and febrile neutropenia (1 pt)). Seven patients had evidence of disease progression and were removed from study. One patient completed the treatments with a mixed response. One patient had a sudden death while on study. The median duration of therapy was 6 weeks (range 3 weeks to 17 weeks). The accrual was stopped after 14 patients when the interim analysis showed a lack of anti-tumor efficacy and significant toxicity. Conclusion: This phase II study in patients with relapsed / refractory myeloma or amyloidosis demonstrated no evidence of clinical activity with use of Campath. In addition it was also associated with significant toxicity in this population. We do not recommend use of campath as a primary treatment modality in these patients. The lack of efficacy despite demonstrated expression of CD52 on clonal plasma cells once again highlights the need for combining treatments with multiple mechanisms in order to improve the response and outcome in these patients. Whether it can synergize with other therapies at lower doses without significant toxicity remains unknown.

Abstract Background: The p53 tumor suppressor gene has a common sequence polymorphism that results in either proline or arginine at amino-acid position 72. The Pro72 and Arg72 variants have been reported to differ in its functional activity. The Arg72 variant induces apoptosis more efficiently than Pro72 variant by its greater ability to localize to the mitochondria and increase the release of cytochrome c into the cytoplasm. In addition, recent studies have demonstrated that Arg72 variant was a better suppressor of cellular transformation, an activity believed to rely on the pro-apoptotic function of p53. Moreover, the Pro72 variant has been associated with a higher incidence of tumors. Aim: To evaluate the effect of the polymorphic variants of codon 72 and clinical outcome in patients with plasma cell malignancies. Patients and Methods: We analyzed 79 patients with plasma cell malignancies seen at Mayo Clinic between 2000 and 2003. Genomic DNA was extracted from CD138+ sorted plasma cell from bone marrow aspirates. PCR amplification of codon 72 and posterior sequencing was used for the analysis. Results: A total of 79 patients were analyzed. Thirty-four patients (34%) were heterozygous for p53, 57 (59%) homozygous for Arginine and 6 (6%) homozygous for Proline. The distribution among disorders was as follow, 52 patients had MM, 14 patients with SMM and 13 with MGUS. Among patient with MM 25% were Pro/Arg heterozygous, 71 % were Arg/Arg homozygous and 3.8% Pro/Pro homozygous. Survival data among MM patients and genotype were analyzed to Kaplan- Meier method. No significant differences were found among patients who carried homozygous (72R) or heterozygous genotype and overall survival. We exclude the analysis in MGUS and SMM for a low number of patients available. Conclusions: These findings indicate that codon 72 arginine p53 may not be associated with a prolonged survival in patients with Multiple Myeloma, but further study is needed to assess whether this polymorphism is associated with progression of MGUS to MM, age of onset, clinical manifestations, response to treatment etc.

Abstract Background: We reported a high response rate with the combination of lenalidomide plus dexamethasone (Rev/Dex) as initial therapy for newly diagnosed multiple myeloma (Blood2005;106:4050–3). We now present new data on time to progression (TTP), progression free survival (PFS), and overall survival (OS) from this phase II trial, and also include updated response data. Patients and Methods: 34 patients (23 male and 11 female) were enrolled. Lenalidomide was given orally 25 mg daily on days 1–21 of a 28-day cycle. Dexamethasone was given orally at a dose of 40 mg daily on days 1–4, 9–12, 17–20 of each cycle. Patients were allowed to go off treatment after 4 cycles of therapy to pursue autologous stem cell transplantation (SCT), but treatment beyond four cycles was permitted at the physician’s discretion. For patients continuing therapy beyond 4 months, the dose of dexamethasone was reduced to 40 mg on days 1–4 of each cycle. Response was assessed by modified EBMT/International Myeloma Working Group Uniform Response criteria. All patients received aspirin (81 mg or 325 mg daily) as prophylaxis against DVT. Results: The median age was 64 years (range, 32–78). All patients were evaluable for response and toxicity. Median follow up is 21 months. Thirteen patients proceeded to SCT following initial therapy with Rev/Dex and were censored at that time point for purposes of calculation of response, TTP and PFS. Patients who discontinued therapy to proceed to SCT received a median of 4 cycles of therapy (range, 4–13), while those staying on Rev/Dex (n=21) received a median of 19 cycles of therapy (range, 2–30). Thirty-one of 34 patients (91%) achieved an objective response to therapy; including 6 patients (18%) achieving a complete response (CR) and 13 patients (38%) achieving very good partial response for a CR+VGPR rate of 56%. The CR+VGPR rate among the 21 patients staying on Rev/Dex as primary therapy without SCT was 67% (CR 24%, VGPR 43%). Median TTP, PFS, and OS have not been reached (Figure). By Kaplan-Meier method, the estimated 2 year progression rate was 18%. The 2-year PFS rate and OS rate were 74% and 91%, respectively. Fifty-five percent of patients experienced grade 3 or higher non-hematologic toxicity at any point during therapy, most commonly fatigue (21%), neutropenia (21%), anxiety (6%), pneumonitis (6%), muscle weakness (6%), and rash (6%). Two patients died on study: one attributed to infection unrelated to therapy, the patient had stopped all therapy for over a month before the fatal infection occurred; the other death was due to infection felt possibly related to therapy. One patient developed a pulmonary embolism (grade 4 toxicity), but recovered with therapy; no other patient developed deep vein thrombosis or pulmonary embolism. Conclusion: Rev/Dex is highly active and well tolerated in the treatment of newly diagnosed multiple myeloma with a high CR+VGPR rate of 56% for the trial, and 67% among the subset of patients receiving this regimen as primary therapy. Responses are durable with a low progression rate at 2 years.

Abstract Background: Plasma cell leukemia (PCL) is a rare plasma cell (PC) dyscrasia which may be designated as primary (PPCL) or de novo PCL when recognized at the time of diagnosis and secondary (SPCL) when there is leukemic transformation of a previously recognized multiple myeloma (MM). PCL has been reported to exhibit distinct clinical and immunophenotypic features that distinguish it from MM, but little is known about the specific genetics of this disease. To better understand the genetic features of the clonal PC from PPCL and SCPL we assessed in these patients the molecular and cytogenetic abnormalities most commonly found in MM. Patients and Methods: In our study we analyzed 3 groups of patients; 18 with PPCL, 23 with SPCL and a control group of 345 newly diagnosed MM previously published. Diagnostic criteria for PCL followed the presence of >2 x103/L PC in PB (Kyle et al. Arch Intern Med1974; 133–813–8). Cytogenetic abnormalities were assessed by the c-Ig FISH method; mutational analysis was performed using Conformational-sensitive gel electrophoresis (CSGE). Methylation was analyzed by methyl specific PCR (MSP) after bisulfite genomic DNA modification. Results: Translocation of immunoglobulin heavy chain with Cyclin D1 (t (11; 14)) was present in 76.9% (10 of 13) of PPCL, 71% (5 of 7) of SPCL, in contrast to 15.8% (53 of 336) of MM cases. Translocations’ involving the FGFR3-MMSET genes (4p16.3 locus) and c-MAF (16q32) genes were not observed among 10 patients studied with PPCL, but were present in 12.7 % each in SPCL. The t (4;14)(p16;q32) was present in 12.7% cases of MM and the t(14;16)(q32;q23) was present in 4.6 % of MM cases. Deletion of 17p13.1 (p53 locus) was found in 10% (37 of 345) of MM cases, 53.8% (7 of 13) for PPCL and 42.8% (3 of 7) for SPCL. Deletion of 13q was present in 54.2% (176 of 325) of MM, 76.9 % (10 of 13) of PPCL and 57.1% of SPCL. Ras mutations were found in 15% (2/13) of PPCL, located in codon 1 and 2 of the K-ras gene. In addition, 23% for SPCL presented mutations in the N-ras gene. Two mutations were located in codon 2 of N-ras and 1 patients in showed a mutation in codon 1 of K-ras gene. Ras mutations were present in 27% of MM cases. Mutations for p53 gene were present in 30.7% (4/13) of PPCL, 17% (3/17) for SPCL and 5% for MM. Methylation specific PCR for p16 gene was found in 23% (3/13) of PPCL, 29% of SPCL and 33.9% (149/439) of MM. Hypermethylation of p14 was not detected in PPCL but a 23 % was found in SPCL. Conclusions: In this study we demonstrate that PCs from PPCL more frequently carry the t (11; 14). Comparing SPCL and MM, PC’s from de novo PPCL do not show t (4; 14) or (16; 14). Deletion of 13q was more prevalent among patients with PPCL. Ras mutations appear to be as frequent in MM as in PPCL and SPCL. Mutations in p53 appeared to be more prevalent in PPCL than in SPCL and MM. Hypermethylation of p16 does not differ while hypermethylation of p14 is more frequent in SPCL than PPCL. These characteristics may lead to a different onset or disease evolution of PPCL compared to MM and secondary plasma cell leukemia and this may be important for diagnostic and treatment.

Abstract Introduction: Stem cell transplant is an increasingly widely applied technique for managing amyloidosis. As in multiple myeloma, the treatment would not be expected to be curative and patients would be expected to relapse in most instances. In addition, approximately one-third of patients fail to respond to initial therapy. The role of second transplantation in treatment failures or patients who relapse is reviewed. Patients: Of 242 patients undergoing high dose conditioning and stem cell transplantation for amyloidosis (AL) at the Mayo Clinic, 6 subsequently underwent a second transplant. Results: Patient 1, who had single organ renal amyloid nephrotic syndrome responded and relapsed at 73 months, received a second stem cell transplant achieving a hematologic complete response with normalization of a markedly elevated pre transplant free light chain (59 to 1.9 mg/dL) and is alive at 12 months. Patient 2 relapsed 42 months after transplant for single organ renal amyloidosis; the second stem cell transplant, has normalized his free light chain ratio reduced his urinary protein loss from 5450 to 1482 mg/day and he is alive 21 months following his second transplant (63 months overall). Patient 3 relapsed 34 months after a response of renal and cardiac amyloidosis. After transplant two, he failed to achieve a 50% reduction in his free light chain, began hemodialysis 7 months post transplant and died one year post transplant. Patient 4 with single organ cardiac involvement relapsed 30 months following his first transplant and died on day +5 of his second transplant of an acute pulmonary embolus. Patient 5 was a response failure after his first transplant, had a second transplant 35 months later, having failed Dexamethasone followed by Melphalan/Dexamethasone therapy, and died 3 months later of progressive disease. Patient 6 had single organ vascular involvement manifest by calf and thigh claudication and failed to respond with his first transplant with a persistently elevated free light chain. The second transplant was performed six months after the first without further free light chain reduction and persistent claudication at 11 months. Conclusion: Patients who failed to achieve a hematologic response after a first transplant appear not to benefit from a second course of high dose therapy. Among 4 patients who were previously responsive and relapsed, one achieved a hematologic complete response, one achieved a hematologic partial response, and two died. The two patients achieving a second hematologic response had the longest response duration (73 and 42 months) following their first transplant, and the second response presumably reflects favorable (indolent; non proliferative) biology of the underlying plasma cell dyscrasia. High dose therapy and stem cell transplant may be an effective salvage regimen for patients who responded to a first transplant and whose response lasted greater than 36 months.

Abstract Background: Overall prognosis in CMML is unfavorable. The only curative option is ASCT, yet the limited data available from the largest reported series, reports 2 year overall (OS) and disease free (DFS) survival of only 21% and 18%, respectively [Kroger et al, BJH 2002, 118: 67]. Data on DLI for CMML are generally restricted to case reports. We retrospectively reviewed our experience of ASCT and DLI for adults with CMML. Patients: Seventeen consecutive patients (11 males) with CMML underwent ASCT from 1992 to 2004. At transplant, median (range) age was 50 years (26–60), duration of disease 7 months (2.5–44), and bone marrow (BM) blast count 6% (1–58%). Prior to transplant, 11 had evolved into acute myeloid leukemia (AML). Of these, 10 received standard induction chemotherapy but only one achieved complete remission (CR); 5 had persistent CMML and 4 refractory AML. Karyotype at transplant was either normal (n=9) or revealed isolated monosomy 7 (n=4), complex (n=1), or single, nonrecurrent abnormalities. ASCT: Conditioning was Cytoxan/Total Body Irradiation in all but one who received a non-myeloablative (NMA) regimen (cladrabine/ATG/thiotepa). Stem cell source was HLA-identical sibling in 14 patients and unrelated in 3 peripheral blood (PB) in 7, BM in 8, or both in 2. Median BM mononuclear cell/kg dose was 2.3 (1.7–4.15) x 108 and PB CD34 cell/kg was 5.12 (0.94–7.29) x 106. Graft versus host disease (GVHD) prophylaxis was cyclosporin alone (n=3), with methotrexate (n=12), or prednisone (n=1) or was tacrolimus/methotrexate (n=1). Post-transplant course: All but one patient who died on day 11 of sepsis engrafted (sustained ANC > 500) at a median of 19.5 days (13–31). CR was documented in 13 (76%) post-ASCT. Acute GVHD was grade II-IV (75%) and III-IV (37.5%) and chronic GVHD was extensive (n=37.5%). Seven (41%) demonstrated relapse or persistent disease at a median of 6 months (3–55.5) and 13 (76%) have died due to disease (n=6) or transplant related mortality (n=7). DLI: Six patients underwent DLI for morphologic (4 recurrent/persistent CMML, 1 early AML with extramedullary disease) or cytogenetic relapse (n=1), at a median of 19.5 days (6–52) post-relapse. Median BM blast count at DLI was 3% (1–22%). The median CD3+ cell dose infused was 30.45 x 107 cells/kg (11.2–45.5), given in a median of 3 infusions (range: 1–3). Four did not respond, but two (one with cytogenetic and one with morphologic relapse) achieved a durable CR of 15 months each, both had extensive CGVHD, from which one died of complications. The other relapsed but failed to respond to a second DLI and died of disease. Survival: For the entire cohort, median DFS and OS were 6 months and 7 months, respectively. At last follow up, 4 remain alive, 3 in continuous CR (18%), at 12, 29 (treated with the NMA regimen) and 116 months, respectively. Of the 3 patients surviving in remission, all had transformed to AML prior to ASCT and only one had achieved CR following induction chemotherapy. Multivariate analysis failed to demonstrate any significant effect of age, duration of disease, BM blast %, karyotype or induction chemotherapy on RFS or OS, likely reflecting the small numbers available for analysis. Conclusion: The current study demonstrates anti-CMML activity of both ASCT and DLI although overall outcome is less than encouraging and unpredictable. Novel approaches are needed.

Abstract Patients with multiple myeloma (MM) who undergo high dose therapy (HDT) followed by autologous stem cell transplantation (ASCT) and achieve a complete response (CR) have a superior overall survival (OS) and time to progression (TTP). Thus achieving a CR is an important goal of therapy with ASCT. Cyclophosphamide has significant activity against MM and is often used in high doses prior to ASCT for mobilization of hematopoietic stem cells. We hypothesized that high dose cyclophosphamide (HDC) may further improve CR rates in patients undergoing ASCT. Methods: The Mayo Clinic myeloma transplant database was searched for patients without circulating myeloma cells who had stem cell mobilization with hematopoietic growth factor (HGF) alone or HDC followed by HGF. Relevant demographic, clinical and laboratory characteristics were abstracted. The main outcome studied was the impact of HDC on CR rates and time to progression (TTP) to myeloma. Results: We identified 201 patients without circulating myeloma cells. Of these, 127 were mobilized with HDC and HGF and 74 with HGF alone. The two cohorts were similar with respect to age, gender, isotype, B2M, plasma cell labeling index, cytogenetics, conditioning regimen, disease status at time of transplant with no statistically significant differences between the two cohorts. CR rates were 37.4 and 41.3% (p=0.6115) for patients mobilized with HDC/HGF and HGF respectively. TTP was 19.9 and 17.6 months (p=0.6039) respectively. The median number of collection sessions for patients mobilized with HDC/HGF was 2 (1–10) and those mobilized with HGF was 4 (1–10) (p<0.0001). In a multivariate analysis for TTP, cytogenetics and achieving a CR were the only independent variables (p=0.0012 and p<0.0001). Conclusion: HDC for autologous hematopoietic stem cell collection reduces the number of collections necessary to support HDT/ASCT. However, HDC does not increase CR rates or improve on TTP for patients undergoing ASCT.

Abstract Cancer/testis antigens (CTAs), comprising the MAGE, CTAG, SSX and GAGE families, are expressed in different tumor types and restricted in normal tissues to germ cells of the testis. Many CTAs contain epitopes recognized by cytotoxic T cells and are potential targets for active immunotherapy. In MM, different CTAs have been shown to be expressed in cell lines and patient cells, and are associated with more proliferative and advance stage tumors. However, correlation with survival has never been reported. We undertook a global survey of CTA expression using gene expression profiling of CD138-enriched plasma-cell (PC) RNA in 15 normal, 101 MM, 22 MGUS and 24 SMM samples using the Affymetrix U133A chip (Affymetrix, Santa Clara, CA). 22 CTA genes were differentially expressed across the samples and unsupervised clustering using these genes clearly identifies a group of patients with high CTA expression. Most CTAs have significantly higher expression in MM as compared to SMM and especially MGUS, which has similar expression as normal PCs. As these antigens are not expressed in normal PCs, an upper limit of normal expression (ULN) was derived based on mean+3SD of expression in normal PCs for each CTA. A strict cut-off of normalized expression value greater than 2xULN was used to assign positive expression for each CTA genes. Using this method, the most commonly expressed CTAs are MAGE-A3 (73% of MM), MAGE-C1 (45%), MAGE-A6 (35%), SSX-1 (21%), GAGE-5 (18%) and NY-ESO-1 (14%). We then assigned patients with expression of more than 2 of these genes as having a CTA signature and correlated with clinical parameters. 45 patents (41 MM and 4 SMM) have the CTA signature. These patients have a significantly higher PCLI (median 0.2 v 0.7, p=0.0003). In fact, there is a significant correlation between the number of positive CTAs and PCLI (r=0.59, p<0.0001). Interestingly, there is no association between patients with a CTA signature and any of the recurrent genetic abnormalities (IgH translocations, chromosome 13 deletion and TC classes), yet MM patients with this signature have a significantly shorter survival (median 459 days vs not reached, log-rank p=0.017). A prognostic hierarchy exists amongst these CTAs. Only MAGE-A6, MAGE-A12, SSX-1 and SSX-5 expression has significant prognostic implications with the SSX family conferring the worse prognosis. Using a restricted panel of 3 CTAs (SSX-1, -5 and MAGE-A12), about 28% of MM patients expressing one or more of these genes can be identified with poor survival (median less than 1 year) that is independent of genetic subtypes. The genes differentially expressed between patients with and without the CTA signature are mainly involved in cell cycle regulation. Since the expression of this large set of CTAs appears to be under epigenetic control, we speculate that the same epigenetic processes that lead to dysregulation of the cell cycle also cause ectopic expression of CTA genes. As CTA expression is rare in MGUS, epigenetic processes may therefore also mediate transformation from MGUS to MM. These poor prognosis patients represent good candidates for novel therapies targeting the epigenetic machinery.

Abstract Background: Patients with SMM/IMM are at high risk for progression to active MM and are appropriate candidates for chemoprevention trials. High IL-1beta levels are a useful surrogate marker for progression from SMM/IMM to active myeloma. Methods: We carried out a Phase II clinical trial of IL-1Ra (Anakinra) in patients with SMM/IMM to determine the biologic activity, progression-free rate, and toxicity of IL-1Ra. Since IL-1beta induces paracrine IL-6, we hypothesized that IL-1Ra would inhibit IL-6 production and myeloma cell growth. 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. Patients received 100 mg of Anakinra (IL-1Ra) SQ qd for a total duration of 6 months. Non-progressors were allowed to continue on therapy with IL-1Ra until they converted to active myeloma. IL-1beta levels were measured in a bioassay with a read out of IL-1 inducible IL-6 production. CRP levels served as a surrogate for IL-6 production. Results: Thirty-six patients are included for analysis based on intent to treat at diagnosis. At baseline, twenty-nine patients had elevated functional IL-1beta levels consistent with progressive disease and 12 patients had radiologic evidence of disease on bone survey. The median TTP for the entire group was 1 year and 2 patients exhibited a minor response based on M-protein reduction. A proportional hazards analysis was performed and the variables examined were: % bone marrow plasma cells, plasma cell labeling index (PCLI), circulating plasma cells, albumin, M-protein level, IgA subtype, CRP, CRP % reduction ≥ one-third, beta-2 microglobulin, creatinine, calcium, hemoglobin, urine total protein, presence of lytic bone disease, and IL-1 level. Univariate Cox model results showed that % BMPC, PCLI, circulating plasma cells, CRP % reduction, presence of lytic disease, and IL-1 level were all statistically significant (p < .05) variables. However, only the CRP % reduction from baseline remained significant in the multivariate analysis (p < 0.01). The median TTP for patients without (n=18) and with (n=18) a decrease in CRP was 6 months and > 2 years, respectively (p < .0001). Toxicities included injection site reactions during the first month of therapy and asymptomatic neutropenia necessitating a reduction in therapy to every other day. Five patients in whom the CRP decreased and the baseline PCLI was > 0 also demonstrated a parallel decrease in the PCLI. Several of the patients with progressive disease on IL-1Ra alone could later be rescued with the addition of low dose dexamethasone (20 mg once a week) suggesting that the endogenous IL-1beta levels were too high to inhibit with IL-1Ra alone. Conclusion: In summary, IL-1Ra can prolong the TTP to active myeloma in responsive SMM/IMM patients through inhibition of IL-6 production (decrease in CRP) and myeloma cell growth. Figure Figure