Bortezomib with lenalidomide and dexamethasone versus lenalidomide and dexamethasone alone in patients with newly diagnosed myeloma without intent for immediate autologous stem-cell transplant (SWOG S0777): a randomised, open-label, phase 3 trial.

BACKGROUND: Lenalidomide plus dexamethasone is a reference treatment for patients with newly diagnosed myeloma. The combination of the proteasome inhibitor bortezomib with lenalidomide and dexamethasone has shown significant efficacy in the setting of newly diagnosed myeloma. We aimed to study whether the addition of bortezomib to lenalidomide and dexamethasone would improve progression-free survival and provide better response rates in patients with previously untreated multiple myeloma who were not planned for immediate autologous stem-cell transplant. METHODS: In this randomised, open-label, phase 3 trial, we recruited patients with newly diagnosed multiple myeloma aged 18 years and older from participating Southwest Oncology Group (SWOG) and National Clinical Trial Network (NCTN) institutions (both inpatient and outpatient settings). Key inclusion criteria were presence of CRAB (C=calcium elevation; R=renal impairment; A=anaemia; B=bone involvement) criteria with measurable disease (measured by assessment of free light chains), Eastern Cooperative Oncology Group (ECOG) performance status of 0-3, haemoglobin concentration 9 g/dL or higher, absolute neutrophil count 1 × 103 cells per mm3 or higher, and a platelet count of 80 000/mm3 or higher. We randomly assigned (1:1) patients to receive either an initial treatment of bortezomib with lenalidomide and dexamethasone (VRd group) or lenalidomide and dexamethasone alone (Rd group). Randomisation was stratified based on International Staging System stage (I, II, or III) and intent to transplant (yes vs no). The VRd regimen was given as eight 21-day cycles. Bortezomib was given at 1·3 mg/m2 intravenously on days 1, 4, 8, and 11, combined with oral lenalidomide 25 mg daily on days 1-14 plus oral dexamethasone 20 mg daily on days 1, 2, 4, 5, 8, 9, 11, and 12. The Rd regimen was given as six 28-day cycles. The standard Rd regimen consisted of 25 mg oral lenalidomide once a day for days 1-21 plus 40 mg oral dexamethasone once a day on days 1, 8, 15, and 22. The primary endpoint was progression-free survival using a prespecified one-sided stratified log rank test at a significance level of 0·02. Analyses were intention to treat. This trial is registered with ClinicalTrials.gov, number NCT00644228. FINDINGS: Between April, 2008, and February, 2012, we randomly assigned 525 patients at 139 participating institutions (264 to VRd and 261 to Rd). In the randomly assigned patients, 21 patients in the VRd group and 31 in the Rd group were deemed ineligible based mainly on missing, insufficient, or early or late baseline laboratory data. Median progression-free survival was significantly improved in the VRd group (43 months vs 30 months in the Rd group; stratified hazard ratio [HR] 0·712, 96% CI 0·56-0·906; one-sided p value 0·0018). The median overall survival was also significantly improved in the VRd group (75 months vs 64 months in the Rd group, HR 0·709, 95% CI 0·524-0·959; two-sided p value 0·025). The rates of overall response (partial response or better) were 82% (176/216) in the VRd group and 72% (153/214) in the Rd group, and 16% (34/216) and 8% (18/214) of patients who were assessable for response in these respective groups had a complete response or better. Adverse events of grade 3 or higher were reported in 198 (82%) of 241 patients in the VRd group and 169 (75%) of 226 patients in the Rd group; 55 (23%) and 22 (10%) patients discontinued induction treatment because of adverse events, respectively. There were no treatment-related deaths in the Rd group, and two in the VRd group. INTERPRETATION: In patients with newly diagnosed myeloma, the addition of bortezomib to lenalidomide and dexamethasone resulted in significantly improved progression-free and overall survival and had an acceptable risk-benefit profile. FUNDING: NIH, NCI, NCTN, Millennium Pharmaceuticals, Takeda Oncology Company, and Celgene Corporation.

Multiple Myeloma, Version 3.2017, NCCN Clinical Practice Guidelines in Oncology.

Multiple myeloma (MM) is caused by the neoplastic proliferation of plasma cells. These neoplastic plasma cells proliferate and produce monoclonal immunoglobulin in the bone marrow causing skeletal damage, a hallmark of multiple myeloma. Other MM-related complications include hypercalcemia, renal insufficiency, anemia, and infections. The NCCN Multiple Myeloma Panel members have developed guidelines for the management of patients with various plasma cell dyscrasias, including solitary plasmacytoma, smoldering myeloma, multiple myeloma, systemic light chain amyloidosis, and Waldenström's macroglobulinemia. The recommendations specific to the diagnosis and treatment of patients with newly diagnosed MM are discussed in this article.

NCCN Guidelines Insights: Multiple Myeloma, Version 3.2016.

These NCCN Guidelines Insights highlight the important updates/changes specific to the 2016 version of the NCCN Clinical Practice Guidelines in Oncology for Multiple Myeloma. These changes include updated recommendations to the overall management of multiple myeloma from diagnosis and staging to new treatment options.

Structural optimization of non-nucleoside DNA methyltransferase inhibitor as anti-cancer agent.

Inhibition of DNA methyltransferase 1 (DNMT1) can reverse the malignant behavior of cancer cells by restoring expression of aberrantly silenced genes that are required for differentiation, senescence, and apoptosis. Clinically used DNMT1 inhibitors decitabine and azacitidine inhibit their target by covalent trapping after incorporation into DNA as azacytidine analogs. These nucleoside compounds are prone to rapid enzymatic inactivation in blood, posing challenges to the development of purely epigenetic dosing schedules. Non-nucleoside compounds that suppress expression or function of DNMT1 may overcome this problem. Using a high-throughput PCR-based site specific chromatin condensation assay, we identified a compound that reactivated Cyclin-Dependent Kinase Inhibitor 2A (CDKN2A) in myeloma cells and suppressed expression of DNMT1 from a library of 5120 chemically diverse small molecules. Lead optimization was performed to generate 26 new analogs with lung cancer proliferation and DNMT1 expression as activity readout. Two of the new derivatives showed 2 fold improvement of growth inhibiting potency and also decreased DNMT1 protein levels in lung cancer cells.

Myeloma is characterized by stage-specific alterations in DNA methylation that occur early during myelomagenesis.

Epigenetic changes play important roles in carcinogenesis and influence initial steps in neoplastic transformation by altering genome stability and regulating gene expression. To characterize epigenomic changes during the transformation of normal plasma cells to myeloma, we modified the HpaII tiny fragment enrichment by ligation-mediated PCR assay to work with small numbers of purified primary marrow plasma cells. The nano-HpaII tiny fragment enrichment by ligation-mediated PCR assay was used to analyze the methylome of CD138(+) cells from 56 subjects representing premalignant (monoclonal gammopathy of uncertain significance), early, and advanced stages of myeloma, as well as healthy controls. Plasma cells from premalignant and early stages of myeloma were characterized by striking, widespread hypomethylation. Gene-specific hypermethylation was seen to occur in the advanced stages, and cell lines representative of relapsed cases were found to be sensitive to decitabine. Aberrant demethylation in monoclonal gammopathy of uncertain significance occurred primarily in CpG islands, whereas differentially methylated loci in cases of myeloma occurred predominantly outside of CpG islands and affected distinct sets of gene pathways, demonstrating qualitative epigenetic differences between premalignant and malignant stages. Examination of the methylation machinery revealed that the methyltransferase, DNMT3A, was aberrantly hypermethylated and underexpressed, but not mutated in myeloma. DNMT3A underexpression was also associated with adverse overall survival in a large cohort of patients, providing insights into genesis of hypomethylation in myeloma. These results demonstrate widespread, stage-specific epigenetic changes during myelomagenesis and suggest that early demethylation can be a potential contributor to genome instability seen in myeloma. We also identify DNMT3A expression as a novel prognostic biomarker and suggest that relapsed cases can be therapeutically targeted by hypomethylating agents.

An open-label, single-arm, phase 2 (PX-171-004) study of single-agent carfilzomib in bortezomib-naive patients with relapsed and/or refractory multiple myeloma.

Carfilzomib is a selective proteasome inhibitor that binds irreversibly to its target. In phase 1 studies, carfilzomib elicited promising responses and an acceptable toxicity profile in patients with relapsed and/or refractory multiple myeloma (R/R MM). In the present phase 2, multicenter, open-label study, 129 bortezomib-naive patients with R/R MM (median of 2 prior therapies) were separated into Cohort 1, scheduled to receive intravenous carfilzomib 20 mg/m(2) for all treatment cycles, and Cohort 2, scheduled to receive 20 mg/m(2) for cycle 1 and then 27 mg/m(2) for all subsequent cycles. The primary end point was an overall response rate (≥ partial response) of 42.4% in Cohort 1 and 52.2% in Cohort 2. The clinical benefit response (overall response rate + minimal response) was 59.3% and 64.2% in Cohorts 1 and 2, respectively. Median duration of response was 13.1 months and not reached, and median time to progression was 8.3 months and not reached, respectively. The most common treatment-emergent adverse events were fatigue (62.0%) and nausea (48.8%). Single-agent carfilzomib elicited a low incidence of peripheral neuropathy-17.1% overall (1 grade 3; no grade 4)-in these pretreated bortezomib-naive patients. The results of the present study support the use of carfilzomib in R/R MM patients. This trial is registered at www.clinicaltrials.gov as NCT00530816.

A phase 2 study of single-agent carfilzomib (PX-171-003-A1) in patients with relapsed and refractory multiple myeloma.

Carfilzomib is a next-generation, selective proteasome inhibitor being evaluated for the treatment of relapsed and refractory multiple myeloma. In this open-label, single-arm phase 2 study (PX-171-003-A1), patients received single-agent carfilzomib 20 mg/m(2) intravenously twice weekly for 3 of 4 weeks in cycle 1, then 27 mg/m(2) for ≤ 12 cycles. The primary endpoint was overall response rate (≥ partial response). Secondary endpoints included clinical benefit response rate (≥ minimal response), duration of response, progression-free survival, overall survival, and safety. A total of 266 patients were evaluable for safety, 257 for efficacy; 95% were refractory to their last therapy; 80% were refractory or intolerant to both bortezomib and lenalidomide. Patients had median of 5 prior lines of therapy, including bortezomib, lenalidomide, and thalidomide. Overall response rate was 23.7% with median duration of response of 7.8 months. Median overall survival was 15.6 months. Adverse events (AEs) were manageable without cumulative toxicities. Common AEs were fatigue (49%), anemia (46%), nausea (45%), and thrombocytopenia (39%). Thirty-three patients (12.4%) experienced peripheral neuropathy, primarily grades 1 or 2. Thirty-three patients (12.4%) withdrew because of an AE. Durable responses and an acceptable tolerability profile in this heavily pretreated population demonstrate the potential of carfilzomib to offer meaningful clinical benefit. This trial was registered at www.clinicaltrials.gov as #NCT00511238.

Mature results of MM-011: a phase I/II trial of liposomal doxorubicin, vincristine, dexamethasone, and lenalidomide combination therapy followed by lenalidomide maintenance for relapsed/refractory multiple myeloma.

A previous interim report of MM-011, the first study that combined lenalidomide with anthracycline-based chemotherapy followed by lenalidomide maintenance for relapsed and/or refractory multiple myeloma (RRMM), showed promising safety and activity. We report the long-term outcomes of all 76 treated patients with follow-up ≥ 5 years. This single-center phase I/II study administered lenalidomide (10 mg on days 1-21 of every 28-day cycle), intravenous liposomal doxorubicin (40 mg/m(2) on day 1), dexamethasone (40 mg on days 1-4), and intravenous vincristine (2 mg on day 1). After 4-6 planned induction cycles, lenalidomide maintenance therapy was given at the last tolerated dose until progression, with or without 50 mg prednisone every other day. The median number of previous therapies was 3 (range, 1-7); 49 (64.5%) patients had refractory disease. Forty-three (56.6%) patients received maintenance therapy. Grade 3/4 adverse events occurred during induction and maintenance therapy in 48.7% and 25.6% of patients, respectively. Four (5.3%) treatment-related deaths occurred during induction. Responses were seen in 53.0% (at least partial response) and 71.2% (at least minor response) of patients. Overall, median progression-free survival and overall survival were 10.5 and 19.0 months, respectively; in patients with refractory disease these values were 7.5 and 11.3 months, respectively. Lenalidomide with anthracycline-based chemotherapy followed by maintenance lenalidomide provided durable control in patients with RRMM (ClinicalTrials.gov number, NCT00091624).

Adding Cyclophosphamide to Bortezomib and Dexamethasone was not Associated With Improved Outcomes of Patients With Newly Diagnosed Light Chain Amyloidosis: A Retrospective Study.

INTRODUCTION: Before 2021, the combination of bortezomib, cyclophosphamide, and dexamethasone (VCd) was one of the most used upfront therapy for systemic immunoglobulin light chain (AL) amyloidosis. Recently, daratumumab in combination with VCd resulted in improved outcomes compared to VCd. However, it's still unclear the role of cyclophosphamide in this combination. MATERIALS AND METHODS: We conducted this retrospective single-institutional study to compare the outcomes of upfront bortezomib and dexamethasone with or without cyclophosphamide (VD vs. VCd). RESULTS: Of 136 total patients, 62 received VD and 74 received VCd. The median age was 64 and the median number of organs involved was 2. Hematologic response was achieved among 73.4% patients in the VD arm and 85.9% in the VCd arm at 3 months (P = .15). Best organ response was not different between 2 arms (34.1% vs. 52.9% for VD and VCd arms, respectively; P = .28). After a median follow-up of 24.4 months, 2-year OS for VD and VCd arm was 70.6% and 84.6% respectively. The median overall survival was 70 months for VD arm and not reached for VCd arm (P = .30). There was no statistically significant difference in median time to next therapy (9.3 vs. 13.5 months for VD and VCd arms, respectively. P = .99). CONCLUSION: the addition of cyclophosphamide to VD was not associated with improved outcomes of patients with AL amyloidosis in this retrospective study.

Therapeutic Targeting of Protein Disulfide Isomerase PDIA1 in Multiple Myeloma.

Multiple myeloma is a genetically complex hematologic neoplasia in which malignant plasma cells constantly operate at the maximum limit of their unfolded protein response (UPR) due to a high secretory burden of immunoglobulins and cytokines. The endoplasmic reticulum (ER) resident protein disulfide isomerase, PDIA1 is indispensable for maintaining structural integrity of cysteine-rich antibodies and cytokines that require accurate intramolecular disulfide bond arrangement. PDIA1 expression analysis from RNA-seq of multiple myeloma patients demonstrated an inverse relationship with survival in relapsed or refractory disease, supporting its critical role in myeloma persistence. Using a structure-guided medicinal chemistry approach, we developed a potent, orally bioavailable small molecule PDIA1 inhibitor CCF642-34. The inhibition of PDIA1 overwhelms the UPR in myeloma cells, resulting in their apoptotic cell death at doses that do not affect the normal CD34+ hematopoietic stem and progenitor cells. Bortezomib resistance leads to increased PDIA1 expression and thus CCF642-34 sensitivity, suggesting that proteasome inhibitor resistance leads to PDIA1 dependence for proteostasis and survival. CCF642-34 induces acute unresolvable UPR in myeloma cells, and oral treatment increased survival of mice in the syngeneic 5TGM1 model of myeloma. Results support development of CCF642-34 to selectively target the plasma cell program and overcome the treatment-refractory state in myeloma.

DNA methylation inhibition in myeloma: Experience from a phase 1b study of low-dose continuous azacitidine in combination with lenalidomide and low-dose dexamethasone in relapsed or refractory multiple myeloma.

The DNA methyltransferase inhibitor azacytidine (aza) may reactivate pathways associated with plasma cell differentiation, cell cycle control, apoptosis, and immune recognition and thereby restore sensitivity to lenalidomide (len) and dexamethasone (dex) in relapsed and/or refractory multiple myeloma (RRMM). We aimed to develop an aza regimen that reaches epigenetically active levels 8 times in 28 days with less bone marrow toxicity than the myeloid malignancy standard of 7 consecutive doses to enable safe combination with len. Aza was escalated from 30 mg/m2 once a week up to a predefined maximum of 50 mg/m2 twice a week in combination with GFR-adjusted len (≥ 60 mL/min: 25 mg, 3059 mL/min: 10 mg) day 1 to 21 every 28 days and dex 40 mg once a week followed by a limited expansion study to a total N of 23 at the highest tolerated dose. Fifty-one patients (pts) with RRMM were screened, 42 were treated and 41 were evaluable for response based on at least 1 response assessment or progression after treatment start. The median number of prior lines of therapy was 5 (1-11) and 81% (34) were refractory to len and/or pomalidomide (pom). Two DLTs occurred in different cohorts, 1 neutropenic fever in 1/6 pts on the aza 40 mg/m2 twice a week GFR ≥ 60 mL/min cohort and 1 GGT elevation in 1/6 pts on the aza 50 mg/m2 GFR 30-59 mL/min cohort. An MTD was not reached and aza 50 mg/m2 SC twice a week was chosen for the expansion study. At least possibly related Grade 3/4 AEs occurred in 28 pts (67%) with the following in > 1 pt: neutropenia (N = 16, 38%), anemia (N = 6, 14%), lymphopenia (N = 5, 12%), thrombocytopenia (N = 4, 10%), leukopenia (N = 4, 10%), febrile neutropenia (N = 4, 10%), fatigue (N = 3, 7%), fever (N = 2, 5%), and infection (N = 2, 5%). At a median follow up time for alive pts of 60.2 months (range: 36.1-82.5 months), the overall response rate (≥ partial response) and clinical benefit response rate (≥ minor response) was 22 and 32%, respectively, with 4 very good partial responses (10%), 5 partial responses (12%), and 4 minor responses (10%). The median PFS was 3.1 months (95% confidence interval [CI]: 2.1-5.1 months), median TTP 2.7 months (95% CI: 2.1-7.5 months), and median OS 18.6 months (95% CI: 12.9-33.0 months). Achieving at least minor response and reaching TTP > 6 months was associated with approximately 35% lower median plasma levels of the enzyme that inactivates aza, plasma cytidine deaminase (CDA, P< .0001). Two of the len refractory pts achieved longer disease control than with any prior regimen and 1 responded immediately after progression on len, bortezomib, and prednisone. Analyses of the methylation state of over 480,000 CpG sites in purified myeloma cells at screening were possible in 11 pts and on day 28 in 8 of them. As in other studies, the majority of differentially methylated CpGs compared to normal plasma cells were hypomethylated in myeloma. Treatment decreased the number of CpGs that were differentially methylated in normal plasma cells by > 0.5% in 6 and by > 5% in 3 of the 8 pts, most pronounced in 2 pts with clinically convincing aza contribution who achieved a reduction in overall differentially methylated CpGs by 23 and 68%, respectively, associated with increased expression of immunoglobulin genes. The study demonstrated tolerability of twice a week SC aza at 50 mg/m2 with len and dex in RRMM and suggested aza may help overcome the len/pom refractory state, possibly by activating differentiation pathways. Relatively low response rates and association of clinical benefit with low plasma levels of the aza inactivating enzyme CDA suggest the aza regimen will need to be optimized further and pt selection may be required to maximize benefit.

Longer term follow-up of the randomized phase III trial SWOG S0777: bortezomib, lenalidomide and dexamethasone vs. lenalidomide and dexamethasone in patients (Pts) with previously untreated multiple myeloma without an intent for immediate autologous stem cell transplant (ASCT).

SWOG S0777, a randomized phase III trial, compared bortezomib, lenalidomide and dexamethasone (VRd) with lenalidomide and dexamethasone (Rd). This updated analysis includes 460 patients evaluable for survival endpoints: 225 eligible and analyzable patients were randomized to Rd and 235 to VRd. The 6-month induction was six 28-day cycles of Rd and eight 21-day cycles of VRd followed by Rd maintenance for all patients. Median follow up is 84 months. Median PFS is 41 months for VRd and 29 months for Rd: stratified hazard ratio (96% Wald Confidence Interval) was 0.742 (0.594, 0.928) and one-sided stratified log-rank P-value 0.003. Median OS for VRd is still not reached with median OS for Rd being 69 months: stratified hazard ratio (96% Wald Confidence Interval) was 0.709 (0.543, 0.926) and stratified two-sided P-value was 0.0114. Both PFS and OS were improved with VRd versus Rd adjusting for age (P-values: 0.013 [PFS]; 0.033 [OS])). Median duration of Rd maintenance was 17.1 months. The addition of bortezomib to lenalidomide dexamethasone for induction therapy results in a statistically significant and clinically meaningful improvement in PFS as well as better OS. VRd continues to represent an appropriate standard of care irrespective of age.

Expression of RASSF1A, an epigenetically silenced tumor suppressor, overcomes resistance to apoptosis induction by interferons.

Resistance of human renal cell carcinoma (RCC) and melanoma to the apoptosis-inducing effects of IFNs was postulated to result from epigenetic silencing of genes by DNA methylation, a common feature of human cancers. To reverse silencing, 5-AZA-deoxycytidine (5-AZA-dC) or selective depletion of DNA methyltransferase 1 (DNMT1) by phosphorothioate oligonucleotide antisense (DNMT1 AS) were employed in cells resistant (<5% terminal deoxynucleotidyl transferase-mediated nick-end labeling positive) to apoptosis induction by IFN-alpha2 and IFN-beta (ACHN, SK-RC-45, and A375). 5-AZA-dC and DNMT1 AS similarly depleted available DNMT1 protein and, at doses that did not cause apoptosis alone, resulted in apoptotic response to IFNs. The proapoptotic tumor suppressor RASSF1A was reactivated by DNMT1 inhibitors in all three cell lines. This was associated with demethylation of its promoter region. IFNs augmented RASSF1A protein expression after reactivation by DNMT1 inhibition. In IFN-sensitive WM9 melanoma cells, expression of RASSF1A was constitutive but also augmented by IFNs. RASSF1A small interfering RNA reduced IFN-induced apoptosis in WM9 cells and in DNMT1-depleted ACHN cells. Conversely, lentiviral expression of RASSF1A but not transduction with empty virus enabled IFN-induced apoptosis. IFN induced tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) and TRAIL-neutralizing antibody inhibited apoptotic response to IFN in RASSF1A-expressing ACHN cells. Accordingly, RASSF1A markedly sensitized to recombinant TRAIL. Normal kidney epithelial cells, although expressing RASSF1A, did not undergo apoptosis in response to IFN or TRAIL but had >400-fold higher TRAIL decoy receptor 1 expression than transduced ACHN cells (real-time reverse transcription-PCR). Results identified RASSF1A as regulated by IFNs and participating in IFN-induced apoptosis at least in part by sensitization to TRAIL.

Targeting the MALAT1/PARP1/LIG3 complex induces DNA damage and apoptosis in multiple myeloma.

Metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) is a highly conserved long non-coding RNA (lncRNA). Overexpression of MALAT1 has been demonstrated to related to poor prognosis of multiple myeloma (MM) patients. Here, we demonstrated that MALAT1 plays important roles in MM DNA repair and cell death. We found bone marrow plasma cells from patients with monoclonal gammopathy of undetermined significance (MGUS) and MM express elevated MALAT1 and involve in alternative non-homozygous end joining (A-NHEJ) pathway by binding to PARP1 and LIG3, two key components of the A-NHEJ protein complex. Degradation of the MALAT1 RNA by RNase H using antisense gapmer DNA oligos in MM cells stimulated poly-ADP-ribosylation of nuclear proteins, defected the DNA repair pathway, and further provoked apoptotic pathways. Anti-MALAT1 therapy combined with PARP1 inhibitor or proteasome inhibitor in MM cells showed a synergistic effect in vitro. Furthermore, using novel single-wall carbon nanotube (SWCNT) conjugated with anti-MALAT1 oligos, we successfully knocked-down MALAT1 RNA in cultured MM cell lines and xenograft murine models. Most importantly, anti-MALAT1 therapy induced DNA damage and cell apoptosis in vivo, indicating that MALAT1 could serve as a potential novel therapeutic target for MM treatment.

Low rate of long-lasting remissions after successful treatment of immune thrombocytopenic purpura with rituximab.

Idiopathic thrombocytopenic purpura (ITP), also known as immune thrombocytopenic purpura, is thought to be caused primarily by the production of autoantibodies directed against platelet surface glycoproteins. Treatment of an acute ITP episode can be difficult, and relapses are common. Recent studies have shown that the anti-CD20 antibody rituximab is effective in the treatment of relapsed and refractory patients. We report the results of a retrospective analysis of rituximab treatment in 14 patients with immune thrombocytopenic purpura. Nine of these patients had a refractory disease, and five patients had a relapse of the thrombocytopenia. The median time since last treatment was 10 days (range 1-470 days). All patients were previously treated with one to seven different regimens, and four had undergone splenectomy. Rituximab was administered at the standard dose of 375 mg/m(2) once per week with a median of 4 infusions (range 2-4). The overall response rate was 64%; 7 of 14 patients (50%) achieved a complete remission (platelet levels > 100 x 10(9)/l), 2 of 14 patients (14%) had a partial remission (platelets > 50 x 10(9)/l), and 5 patients did not respond. The median time to response was 2 weeks (range 1-4) after the first infusion. Responding patients stayed in remission for a median period of 8 weeks (range 10 days-36 months). Three patients (21%) remained in remission after 26 to 156 weeks of follow-up. All of the four splenectomized patients achieved a complete remission after rituximab therapy, and two of them are still in remission after 26 and 156 weeks observation. Our data confirm that rituximab is well tolerated and effective in refractory and relapsed immune thrombocytopenias; however, response duration was short, and only about one fifth of our patients enjoyed a long-lasting remission.

Neuropathy and efficacy of once weekly subcutaneous bortezomib in multiple myeloma and light chain (AL) amyloidosis.

INTRODUCTION: Randomized studies have shown that bortezomib (BTZ) can be given weekly via intravenous (IV) route or twice weekly via subcutaneous (SC) route with lower neuropathy risk and no loss of anti-myeloma efficacy compared to original standard IV twice weekly schedule. Weekly SC should therefore yield the best therapeutic index and is widely used but has not been compared to established administration schedules in the context of a clinical trial. METHODS: Comprehensive electronic medical record review was done for disease control and neuropathy symptoms of 344 consecutive patients who received their first BTZ-containing regimen for myeloma or AL amyloidosis before or after we changed to SC weekly in December 2010. Univariate and multivariable analyses were carried out that adjusted for age, underlying disease, concurrently used anticancer agents, underlying conditions predisposing to neuropathy, and number of prior regimens compared SC weekly to other schedules. RESULTS: Fifty-three patients received BTZ SC weekly, 17 SC twice weekly, 127 IV weekly and 147 IV twice weekly. Risk for neuropathy of any grade was higher with other schedules compared to SC weekly (44.3% vs. 26.9%, p = 0.001) while response rate was similar (72.1% vs. 76.6%, respectively, p = 0.15). Multivariable analyses upheld higher neuropathy risk (Odds ratio 2.45, 95% CI 1.26-4.76, p = 0.008) while the likelihood of not achieving a response (= partial response or better) was comparable (Odds ratio 1.25, 95% CI 0.58-2.71, p = 0.56) for other schedules compared to SC weekly, respectively. Lower neuropathy risk translated into longer treatment duration when BTZ was started SC weekly (p = 0.001). CONCLUSIONS: Weekly SC BTZ has activity comparable to other schedules and causes low rates of neuropathy.

Phase I Study of Anti-GM2 Ganglioside Monoclonal Antibody BIW-8962 as Monotherapy in Patients with Previously Treated Multiple Myeloma.

INTRODUCTION: BIW-8962 is a monoclonal antibody to GM2 ganglioside that shows preclinical activity towards multiple myeloma (MM) cell lines and in animal models bearing MM xenografts. The objective of this study was to determine the safety, tolerability, maximum tolerated dose (MTD), pharmacokinetics, potential immunogenicity, and preliminary clinical efficacy of BIW-8962 in patients with heavily pretreated MM. METHODS: Patients (n = 23) received escalating doses of BIW-8962 (0.03-3 mg/kg) intravenously every 2 weeks in phase Ia. The highest anticipated dose (10 mg/kg) was not tested and the study was discontinued without proceeding to phases Ib and II. RESULTS: The MTD of BIW-8962 was not established and BIW-8962 was relatively well tolerated. No pattern of consistent toxicity could be inferred from treatment-related AEs grade ≥3 and only two dose-limiting toxicities were recorded (atrial thrombosis + cardiomyopathy and chest pain, respectively). In the efficacy evaluable population (n = 22), no patient had a response (complete or partial) and 16 (72.7%) had a best response of stable disease, which was generally not durable. CONCLUSION: BIW-8962 did not show evidence of clinical activity. The study was therefore stopped and further development of BIW-8962 in MM was halted. FUNDING: This work was funded by Kyowa Kirin Pharmaceutical Development, Inc. TRIAL REGISTERED: ClinicalTrials.gov identifier, NCT00775502.

Role of Myeloma-Derived MIF in Myeloma Cell Adhesion to Bone Marrow and Chemotherapy Response.

BACKGROUND: Multiple myeloma (MM) remains an incurable cancer characterized by accumulation of malignant plasma cells in the bone marrow (BM). The mechanism underlying MM homing to BM is poorly elucidated. METHODS: The clinical significance of migration inhibitory factor (MIF) expression was examined by analyzing six independent gene expression profile databases of primary MM cells using the Student's t test and Kaplan-Meier test. Enzyme-linked immunosorbent assay was used to examine MIF expression. In vivo bioluminescent imaging was used to determine MM cell localization and treatment efficacy in human MM xenograft mouse models, with three to four mice per group. MM cell attachment to BM stromal cells (BMSCs) was monitored by cell adhesion assay. MIF regulation of the expression of adhesion molecules was determined by chromatin immunoprecipitation (ChIP) assay. Statistical tests were two-sided. RESULTS: High levels of MIF were detected in MM BM (MIF level in BM plasma: healthy = 10.72 ± 5.788 ng/mL, n = 5; MM = 1811 ± 248.7 ng/mL, n = 10; P < .001) and associated with poor survival of patients (Kaplan-Meier test for MM OS: 87 MIF(high) patients, 86 MIF(low) patients, P = .02). Knocking down MIF impaired MM cell adhesion to BMSCs in vitro and led to formation of extramedullary tumors in SCID mice. MIF acted through surface receptor CXCR4 and adaptor COPS5 to regulate the expression of adhesion molecules ALCAM, ITGAV, and ITGB5 on MM cells. More importantly, MIF-deficient MM cells were sensitive to chemotherapy in vitro when cocultured with BMSCs and in vivo. MIF inhibitor 4-IPP sensitized MM cells to chemotherapy. CONCLUSIONS: MIF is an important player and a novel therapeutic target in MM. Inhibiting MIF activity will sensitize MM cells to chemotherapy.