Lenalidomide-refractory Multiple Myeloma Research Articles

A Systematic Review and Network Meta-analysis of Randomized Data on Efficacy of Novel Therapy Combinations in Patients with Lenalidomide-refractory Multiple Myeloma

IntroductionLenalidomide use in nearly all induction regimens for multiple myeloma (MM) has led to the treatment of lenalidomide-refractory disease becoming one of the most important clinical questions in its treatment. Given the lack of direct comparisons of treatment regimens for lenalidomide-refractory MM, we used a systematic review to identify randomized controlled trials (RCTs) that included lenalidomide-refractory subgroup analysis. MethodsWe performed a systematic review to identify RCTs for MM that enrolled patients with lenalidomide-refractory disease, then performed a network meta-analysis (NMA) using random effects model to compare regimens. ResultsWe identified 123 discrete RCTs, of which 7 reported primary outcomes for lenalidomide-refractory MM. These were linked in 2 discrete networks totaling 1698 lenalidomide-refractory patients. Network 1 compared bortezomib (bort)/dexamethasone (dex) versus other treatments, and analysis showed triplet therapy with pomalidomide (pom)/bort/dex (hazard ratios [HR] 0.65, 95% confidence interval [CI], 0.50–0.84), daratumumab (dara)/bort/dex (HR 0.36, 95% CI, 0.21–0.63), and dara/carfilzomib (carf)/dex (HR 0.38, 95% CI, 0.21–0.69) as more effective than bort/dex. Network 2 compared dex versus other treatments, and analysis showed pom/dex (HR 0.50, 95% CI, 0.40–0.62), isatuximab (isa)/pom/dex (HR 0.30, 95% CI, 0.20–0.44), and elotuzumab (elo)/pom/dex (HR 0.27, 95% CI, 0.16–0.45) as more effective than dex. Within each network, monoclonal antibody (mAb)-containing regimens had lower HRs and higher P-scores than non-mAb regimens, indicating higher likelihood of these regimens being most efficacious. ConclusionThe results of our NMA demonstrated that for lenalidomide-refractory MM, triplet therapy containing mAbs are superior. There is need for further RCTs to better ascertain the best standard of care for these patients.

A Systematic Review and Network Meta-Analysis of Randomized Data on Efficacy of Novel Therapy Combinations in Patients with Lenalidomide Refractory Multiple Myeloma

Introduction: Advancements in the treatment of multiple myeloma (MM) with proteasome inhibitors [bortezomib (bort), carfilzomib (carf)], monoclonal antibodies [daratumumab (dara), isatuximab (isa) and elotozumab (elo)], and immunomodulatory drugs [IMiD) [lenalidomide and pomalidomide (pom)] have improved outcomes. However, using lenalidomide as frontline treatment and maintenance therapy exposes greater numbers of patients to lenalidomide prior to relapse. Consequently, the treatment of lenalidomide-refractory (LR) disease is an increasing area of concern. Given the lack of direct comparisons of different treatment regimens for LR MM, we used a systematic review to identify randomized controlled trials (RCTs) that included subgroup analysis of LR patients. The objective of our study was to compare the efficacy of novel treatment regimens in randomized trials for patients with LR MM using a network meta-analysis. Methods: Three databases were searched: MEDLINE/PubMed, Embase, and Cochrane Registry of Controlled Trials. All studies published between January 1, 2005 and December 30, 2019 were queried using keywords "multiple myeloma" and "randomized controlled trial". Only RCT's were included. Primary outcome was progression free survival (PFS) of patients enrolled in myeloma RCT's. Two independent investigators reviewed all the studies and resolved any conflict through mutual discussion. WNetwork meta-analysis using random-effects model was performed to generate direct and indirect comparisons between various treatment groups. Frequentist method was used to rank the interventions and P-score was generated. A higher P score (close to 1.00) corresponded to superior progression free survival. A P-value of <0.05 was considered statistically significant. Hazard ratios (HR) with 95% confidence interval (CI) were calculated. I2statistic was used to assess heterogeneity between the studies as defined by the Cochrane Handbook for Systematic Reviews with a value >50% considered as significant heterogeneity. We used 'R' (Bell Labs, Murray Hill, NJ, USA) for generating our statistical analysis and plots. Results: Our initial search strategy yielded 1171 results. After excluding duplicates, trials in progress, subset analysis and non-randomized studies, 123 RCTs were identified. Only 8 studies clearly reported outcomes of patients with LR myeloma and 7 studies (1698 patients) were included in final analysis of two discrete networks. Pom/bort/dex (HR: 0.65,95% CI: 0.50-0.84), dara/bort/dex (HR: 0.36, 95% CI: 0.21-0.63), and dara/carf/dex (HR: 0.38, 95% CI: 0.21-0.69) were all found to have improved PFS compared to bort/dex (Figure 2). These interventions were ranked as follows: Dara-bort-dex was the most efficacious with a P-score of 0.8758, followed by Dara/carf/Dex (P of 0.8514), Pom/bort/dex (P of 0.4791), Carf/dex (P of 0.2707) and Bort/dex (P of 0.0231). Within Network 2 (Figure 3), pom/dex (HR :0.50, 95% CI= 0.40-0.62), isa/pom/dex (HR: 0.30, 95% CI= 0.20-0.44) and elo/pom/dex (HR: 0.27, 95% CI=0.16-0.45), were all found to have improved PFS compared to dexamethasone (Figure 4). In Network 2, the ranking of interventions was as follows with Elo-pom-dex (P of 0.8716) the most efficacious, followed by Isa-pom-Dex (P of 0.7932) and Pom-dex (P of 0.3352). Conclusion: The results of our network meta-analysis of 1698 patients with lenalidomide refractory myeloma enrolled in seven randomized myeloma trials demonstrate that for lenalidomide refractory myeloma, triplet therapy is superior to doublet therapy. Regimens with the highest efficacy in this subset of patients were triplets containing monoclonal antibodies (such as dara/elo/isa). There is a need for further randomized data to better ascertain the best standard of care for these patients. Disclosures No relevant conflicts of interest to declare.

Nelfinavir and lenalidomide/dexamethasone in patients with lenalidomide-refractory multiple myeloma. A phase I/II Trial (SAKK 39/10)

The antiretroviral agent nelfinavir has antimyeloma activity and can overcome resistance to bortezomib. Our phase I/II trial investigated whether adding nelfinavir to lenalidomide–dexamethasone can overcome lenalidomide resistance in lenalidomide-refractory multiple myeloma (MM). Twenty-nine patients were included (high-risk cytogenetic aberrations 31%; ≥2 prior therapy lines 93%; lenalidomide–bortezomib double-refractory 34%). Twenty-four patients (83%) had prior bortezomib and 10 (34%) were lenalidomide–bortezomib double-refractory. They received four cycles of nelfinavir 2500 mg/day with standard-dose lenalidomide (25 mg days 1–21) and dexamethasone (40/20 mg days 1, 8, 15, 22). Minor response or better was achieved in 16 patients (55%; 95% CI 36–74%), including 40% of those who were lenalidomide–bortezomib double-refractory, and partial response or better in nine patients (31%; 95% CI 15–51%). Median progression-free survival was 3.4 (95% CI 2.0–4.9) months and median overall survival 21.6 (13.0–50.1) months. Lenalidomide-related pneumonitis, pneumonia, and neutropenic fever occurred, but there were no unexpected adverse events. Peripheral blood mononuclear cells showed a 45% (95% CI 40–51%) reduction in total proteasome activity from baseline and significant induction of unfolded protein response and autophagy. Thus, nelfinavir–lenalidomide–dexamethasone is an active oral combination in lenalidomide-refractory MM.

Lenalidomide combined with low-dose cyclophosphamide and prednisone modulates Ikaros and Aiolos in lymphocytes, resulting in immunostimulatory effects in lenalidomide-refractory multiple myeloma patients.

We recently showed that the outcome of multiple myeloma (MM) patients treated in the REPEAT study (evaluation of lenalidomide combined with low-dose cyclophosphamide and prednisone (REP) in lenalidomide-refractory MM) was markedly better than what has been described with cyclophosphamide-prednisone alone. The outcome with REP was not associated with plasma cell Cereblon expression levels, suggesting that the effect of REP treatment may involve mechanisms independent of plasma cell Cereblon-mediated direct anti-tumor activity. We therefore hypothesized that immunomodulatory effects contribute to the anti-MM activity of REP treatment, rather than plasma cell Cereblon-mediated effects. Consequently, we now characterized the effect of REP treatment on immune cell subsets in peripheral blood samples collected on day 1 and 14 of cycle 1, as well as on day 1 of cycle 2. We observed a significant mid-cycle decrease in the Cereblon substrate proteins Ikaros and Aiolos in diverse lymphocyte subsets, which was paralleled by an increase in T-cell activation. These effects were restored to baseline at day one of the second cycle, one week after lenalidomide interruption. In vitro, lenalidomide enhanced peripheral blood mononuclear cell-mediated killing of both lenalidomide-sensitive and lenalidomide-resistant MM cells in a co-culture system. These results indicate that the Cereblon-mediated immunomodulatory properties of lenalidomide are maintained in lenalidomide-refractory MM patients and may contribute to immune-mediated killing of MM cells. Therefore, combining lenalidomide with other drugs can have potent effects through immunomodulation, even in patients considered to be lenalidomide-refractory.

Phase I/II trial of the oral regimen ixazomib, pomalidomide, and dexamethasone in relapsed/refractory multiple myeloma.

In this phase I/II trial, a triplet regimen of ixazomib (Ixa: 3 or 4 mg), pomalidomide (Pom: 4 mg), and dexamethasone (Dex: 40 mg) was administered to 32 lenalidomide-refractory multiple myeloma (MM) patients; 31 were evaluable for response and toxicity. At dose level 1 (DL1, 3 mg Ixa), 1/3 patients experienced grade 3 fatigue, grade 3 lung infection, grade 4 neutropenia, and grade 4 thrombocytopenia; all were considered dose limiting. Per 3+3 phase I design, an additional 3 patients were enrolled to DL1, with no further dose limiting toxicity (DLT). At dose level 2 (DL2, 4 mg Ixa), 1/3 patients had dose-limiting febrile neutropenia, neutropenia, and thrombocytopenia (grade 4 each). DL2 was expanded to enroll 3 additional patients with no further DLT, establishing the recommended phase II dose (RP2D). In phase II, 19 additional patients were treated at RP2D. With a median follow-up of 11.9 months, 48% achieved ≥partial response (PR), with 5 patients (20%) achieving very good partial response (VGPR) and 76% experiencing ≥stable disease. The most common adverse events (≥grade 2) were anemia, neutropenia, thrombocytopenia, and infections. Peripheral neuropathy was infrequent. In summary, Ixa/Pom/Dex is a well-tolerated and effective oral combination therapy for patients with relapsed/refractory MM.

Phase I/II trial of the oral regimen ixazomib, pomalidomide, and dexamethasone in relapsed/refractory multiple myeloma

In this phase I/II trial, a triplet regimen of ixazomib (Ixa: 3 or 4 mg), pomalidomide (Pom: 4 mg), and dexamethasone (Dex: 40 mg) was administered to 32 lenalidomide-refractory multiple myeloma (MM) patients; 31 were evaluable for response and toxicity. At dose level 1 (DL1, 3 mg Ixa), 1/3 patients experienced grade 3 fatigue, grade 3 lung infection, grade 4 neutropenia, and grade 4 thrombocytopenia; all were considered dose limiting. Per 3+3 phase I design, an additional 3 patients were enrolled to DL1, with no further dose limiting toxicity (DLT). At dose level 2 (DL2, 4 mg Ixa), 1/3 patients had dose-limiting febrile neutropenia, neutropenia, and thrombocytopenia (grade 4 each). DL2 was expanded to enroll 3 additional patients with no further DLT, establishing the recommended phase II dose (RP2D). In phase II, 19 additional patients were treated at RP2D. With a median follow-up of 11.9 months, 48% achieved ⩾partial response (PR), with 5 patients (20%) achieving very good partial response (VGPR) and 76% experiencing ⩾stable disease. The most common adverse events (⩾grade 2) were anemia, neutropenia, thrombocytopenia, and infections. Peripheral neuropathy was infrequent. In summary, Ixa/Pom/Dex is a well-tolerated and effective oral combination therapy for patients with relapsed/refractory MM.Leukemia accepted article preview online, 18 December 2017. doi:10.1038/leu.2017.352.

Pomalidomide, bortezomib, and dexamethasone for patients with relapsed lenalidomide-refractory multiple myeloma

AbstractThis phase 1/2 trial evaluated the maximum tolerated doses, safety, and efficacy of pomalidomide, bortezomib, and dexamethasone (PVD) combination in patients with relapsed lenalidomide-refractory multiple myeloma (MM). In phase 1, dose level 1 consisted of pomalidomide (4 mg by mouth on days 1 to 21), IV or subcutaneous bortezomib (1.0 mg/m2 on days 1, 8, 15, and 22), and dexamethasone (40 mg by mouth on days 1, 8, 15, and 22) given every 28 days. Bortezomib was increased to 1.3 mg/m2 for dose level 2 and adopted in the phase 2 expansion cohort. We describe the results of 50 patients. Objective response rate was 86% (95% confidence interval [CI], 73-94) among all evaluable patients (stringent complete response, 12%; complete response, 10%; very good partial response, 28%; and partial response, 36%) and 100% among high-risk patients. Within a median follow-up of 42 months, 20% remain progression free, 66% are alive, and 4% remain on treatment. Median progression-free survival was 13.7 months (95% CI, 9.6-17.7). The most common toxicities were neutropenia (96%), leukopenia (84%), thrombocytopenia (82%), anemia (74%), and fatigue (72%); however, the majority of these were grade 1 or 2. The most common grade ≥3 toxicities included neutropenia (70%), leukopenia (36%), and lymphopenia (20%). Deep vein thrombosis occurred in 5 patients. In conclusion, PVD is a highly effective combination in lenalidomide-refractory MM patients. Weekly administration of bortezomib enhanced tolerability and convenience. Toxicities are manageable, mostly consisting of mild cytopenias with no significant neuropathy. This trial was registered at www.clinicaltrials.gov as #NCT01212952.

Phase 1/2 study of lenalidomide combined with low-dose cyclophosphamide and prednisone in lenalidomide-refractory multiple myeloma

AbstractThe prognosis of multiple myeloma (MM) patients who become refractory to lenalidomide and bortezomib is very poor, indicating the need for new therapeutic strategies for these patients. Next to the development of new drugs, the strategy of combining agents with synergistic activity may also result in clinical benefit for patients with advanced myeloma. We have previously shown in a retrospective analysis that lenalidomide combined with continuous low-dose cyclophosphamide and prednisone (REP) had remarkable activity in heavily pretreated, lenalidomide-refractory MM patients. To evaluate this combination prospectively, we initiated a phase 1/2 study to determine the optimal dose and to assess its efficacy and safety in lenalidomide-refractory MM patients. The maximum tolerated dose (MTD) was defined as 25 mg lenalidomide (days 1-21/28 days), combined with continuous cyclophosphamide (50 mg/d) and prednisone (20 mg/d). At the MTD (n = 67 patients), the overall response rate was 67%, and at least minimal response was achieved in 83% of the patients. Median progression-free survival and overall survival were 12.1 and 29.0 months, respectively. Similar results were achieved in the subset of patients with lenalidomide- and bortezomib-refractory disease as well as in patients with high-risk cytogenetic abnormalities, defined as t(4;14), t(14;16), del(17p), and/or ampl(1q) as assessed by fluorescence in situ hybridization. Neutropenia (22%) and thrombocytopenia (22%) were the most common grade 3-4 hematologic adverse events. Infections (21%) were the most common grade 3-5 nonhematologic adverse events. In conclusion, the addition of continuous low-dose oral cyclophosphamide to lenalidomide and prednisone offers a new therapeutic perspective for multidrug refractory MM patients. This trial was registered at www.clinicaltrials.gov as #NCT01352338.

Randomized multicenter phase 2 study of pomalidomide, cyclophosphamide, and dexamethasone in relapsed refractory myeloma

AbstractPomalidomide and low-dose dexamethasone (PomDex) is standard treatment of lenalidomide refractory myeloma patients who have received >2 prior therapies. We aimed to assess the safety and efficacy of the addition of oral weekly cyclophosphamide to standard PomDex. We first performed a dose escalation phase 1 study to determine the recommended phase 2 dose of cyclophosphamide in combination with PomDex (arm A). A randomized, multicenter phase 2 study followed, enrolling patients with lenalidomide refractory myeloma. Patients were randomized (1:1) to receive pomalidomide 4 mg on days 1 to 21 of a 28-day cycle in combination with weekly dexamethasone (arm B) or pomalidomide, dexamethasone, and cyclophosphamide (PomCyDex) 400 mg orally on days 1, 8, and 15 (arm C). The primary end point was overall response rate (ORR). Eighty patients were enrolled (10 in phase 1 and 70 randomized in phase 2: 36 to arm B and 34 to arm C). The ORR was 38.9% (95% confidence interval [CI], 23-54.8%) and 64.7% (95% CI, 48.6-80.8%) for arms B and C, respectively (P = .035). As of June 2015, 62 of the 70 randomized patients had progressed. The median progression-free survival (PFS) was 4.4 (95% CI, 2.3-5.7) and 9.5 months (95% CI, 4.6-14) for arms B and C, respectively (P = .106). Toxicity was predominantly hematologic in nature but was not statistically higher in arm C. The combination of PomCyDex results in a superior ORR and PFS compared with PomDex in patients with lenalidomide refractory multiple myeloma. The trial was registered at www.clinicaltrials.gov as #NCT01432600.

Pomalidomide, Cyclophosphamide, and Dexamethasone Is Superior to Pomalidomide and Dexamethasone in Relapsed and Refractory Myeloma: Results of a Multicenter Randomized Phase II Study

Background: Pomalidomide-dexamethasone results in an overall response rate of 33% and median PFS of 4.2 months in patients with prior lenalidomide and bortezomib (Richardson et al. Blood 2014). In this randomized phase II trial, we compared pomalidomide-dexamethasone (arm B) versus the addition of oral weekly cyclophosphamide to pomalidomide-dexamethasone (arm C) in patients with lenalidomide-refractory multiple myeloma (MM). We have previously reported that the recommended phase II dose of cyclophosphamide with standard-dose pomalidomide + dexamethasone was 400 mg PO D1, 8, 15.Patients and Methods: Eligible patients had relapsed and refractory MM after at least 2 prior therapies and were lenalidomide refractory. Patients had a platelet count ≥ 50,000/mm3 and ANC ≥ 1,000/mm3 (patients with ≥50% bone marrow plasmacytosis were allowed if platelet count was ≥ 30,000/mm3and ANC could be supported with GCSF during screening and therapy). Patients were randomized (1:1) to receive pomalidomide 4 mg PO D1-21 and dexamethasone 40 mg PO D1, 8, 15, 22 (20 mg if older than 75 years) (arm B) with or without oral cyclophosphamide 400 mg PO D1, 8, 15 of a 28-day cycle (arm C). Patients randomized to arm B were allowed to cross over to arm C in the event of disease progression. Thromboprophylaxis was mandated with aspirin, warfarin, or LMWH. The primary endpoint was overall response rate using IMWG criteria. Secondary endpoints included an evaluation of PFS, OS and safety of the two arms.Results: Between 7/2012 and 3/2014, 36 patients were randomized to arm B and 34 to arm C. Patients characteristics were not different between the 2 arms (table below). The median number of prior therapies was 4 (2-12). All patients were lenalidomide refractory and none received prior pomalidomide. After a median follow up of 15 months, the overall response rate (partial response or better) was 39% and 65% (p=0.03) for arm B and C, respectively. The clinical benefit rate (minimal response or better) was 64% and 79% (p=0.2) for arm B and C, respectively. The median PFS was 4.4 months (95% CI 2.3-5.9) for arm B and 9.2 months (95% CI 4.6-16) for arm C (log rank p=0.04). As of July 2014, 28 patients had died (16 arm B, 12 arm C) with median overall survival of 10.5 versus 16.4 months (p=0.08) for arm B and C, respectively. Hematologic grade 3/4 adverse events were more frequent in arm C, although this was not statistically significant (see table). Thirteen patients crossed over and oral weekly cyclophosphamide was added to their tolerated dose of pomalidomide dexamethasone. For those patients, the best response was as follows: 2 PR, 2 MR, and 6 SD, 3 PD.Conclusions: Pomalidomide-dexamethasone in combination with oral weekly cyclophosphamide resulted in a superior response rate and PFS compared to pomalidomide-dexamethasone alone in patients with relapsed and refractory MM. The increased hematologic toxicities, as a result of the addition of oral cyclophosphamide, were manageable.TableArm B (N=36)Arm C (N=34)P valueAge, years, median (range)63 (50-78)64 (47-80)0.7Male, n (%)23 (64)18 (53)0.3Number of prior therapies, median (range)4 (2-12)4 (2-9)0.5Bortezomib refractory, n (%)28 (78)24 (71)0.3Carfilzomib refractory, n (%)16 (44)13 (38)0.5Prior high-dose therapy, n (%)27 (75)28 (82)0.6Prior alkylating agent, n (%)32 (89)32 (94)1B2-microglobulin, median (range)3.2 (1.6-10)3.6 (1.5-13.9)0.5Serum creatinine, median (range)1 (0.5-2.3)0.9 (0.6-2.1)0.6High-risk cytogenetics, n (%)5 (24)6 (28)0.8Deletion 17p, n (%)3 (14)4 (20)0.8t(4;14), n (%)3 (14)3 (14)0.9Trisomy or tetrasomy 1q, n (%)11 (55)6 (33)0.4Best response (partial response or better), n (%)14 (39)22 (65)0.03Clinical benefit rate (MR or better), n (%)23 (64)27 (79)0.2Grade 3/4 neutropenia, n (%)12 (33)17 (50)0.2Grade 3/4 febrile neutropenia, n (%)4 (11)6 (18)0.5Grade 3/4 thrombocytopenia, n (%)2 (5)5 (15)0.2Grade 3/4 anemia, n (%)3 (8)7 (20)0.2Grade 3/4 pneumonia, n (%)4 (11)3 (9)1Grade 3/4 fatigue, n (%)2 (5)4 (12)0.4Number of serious adverse events1720 DisclosuresBaz:Celgene: Research Funding; Millenium: Research Funding; Bristol-Myers Squibb: Research Funding; Karypharm: Research Funding; Sanofi: Research Funding. Off Label Use: Pomalidomide cyclophosphamide dexamethasone in relapsed refractory myeloma. Martin:Sanofi: Research Funding; Novartis: Speakers Bureau. Alsina:Triphase: Research Funding; Millenium: Research Funding. Shain:Onyx / Amgen: Research Funding; Treshold: Research Funding. Chari:Celgene: Membership on an entity’s Board of Directors or advisory committees; Millenium: Membership on an entity’s Board of Directors or advisory committees; Array Biopharma: Membership on an entity’s Board of Directors or advisory committees. Jagannath:Celgene: Honoraria; Millennium: Honoraria; Sanofi: Honoraria.

Phase 1 Study of the Novel Kinesin Spindle Protein Inhibitor ARRY-520 + Carfilzomib in Patients with Relapsed and/or Refractory Multiple Myeloma

AbstractAbstract 4082 Background:ARRY-520, a novel kinesin spindle protein (KSP) inhibitor, has been studied as a single agent and in combination with dexamethasone, and demonstrated promising clinical activity in patients with bortezomib- and lenalidomide-refractory multiple myeloma (MM). Carfilzomib, a novel irreversible proteasome inhibitor (PI), has also demonstrated single agent activity in relapsed and refractory MM, and recently received regulatory approval for this indication. Preclinical data support the presence of synergy with the combination of a PI and a KSP inhibitor via the latter's ability to down-regulate Mcl-1, supporting our hypothesis that the combination of carfilzomib and ARRY-520 (Car-ARRY) would be highly active in relapsed and/or refractory myeloma. We therefore aimed to combine these two agents for the first time, and here report the initial findings from the phase I dose-escalation in patients with relapsed and/or refractory MM. Methods:The primary objective was to determine the maximum tolerated dose (MTD) and the safety/tolerability of the Car-ARRY combination. Secondary objectives were to determine efficacy as measured by the overall response rate, time to progression, progression free survival and time to next therapy. Patients had to have myeloma that was relapsed and/or refractory, be ineligible for autologous stem cell transplant, bortezomib refractory/intolerant, and prior lenalidomide exposure. ARRY-520 was administered intravenously over 1 hour on days 1, 2, 15 and 16, while carfilzomib was administered intravenously over 30 minutes on days 1, 2, 8, 9, 15 and 16 on a 28 day cycle. All patients received growth factor support with filgrastim.Dose-escalation used a standard 3+3 schema proceeded based on dose-limiting toxicities (DLTs) during cycle 1, with planned escalation of the dose of ARRY-520. Dose level 1 was ARRY-520 0.75 mg/m2, and carfilzomib was dosed at 20 mg/m2 for cycle 1 on days 1 and 2 and all subsequent dose were at 27 mg/m2. Adverse events (AEs) were graded by NCI-CTCAE v4, while responses were assessed by the modified International Uniform Response Criteria. Results:To date, 8 patients have been enrolled in the ongoing dose escalation phase. The median age was 66 (range 47–80), 6/8 were males, and the median number of prior therapies was 4 (range 2–10). 7/8 patients had undergone prior autologous stem cell transplant, and all patients were bortezomib refractory or intolerant. In the first cohort, 3 patients were enrolled and no dole limiting toxicity (DLT) was observed. During the second cohort, ARRY-520 was escalated to 1 mg/m2 with carfilzomib at 20/27 mg/m2, and among the first 3 patients, one patient suffered a DLT in the form of an admission for influenza pneumonia with non-neutropenic fever. Expansion of cohort 2 is currently underway.Among the 6 patients who completed the first cycle of therapy, 5 remain on study. In the first cohort, one patient remains on study with 6 cycles and achieved a near complete remission, 1 patient achieved stable disease, and 1 patient suffered disease progression after first cycle. In the second cohort, all three patients who completed the first cycle have stable disease and remain on trial.In the first 6 toxicity-evaluable patients who have completed one cycle, grade (G) 3 events included one each of pneumonia, diarrhea, and hyperglycemia. There was limited hematologic toxicity with 4/6 patients with G1/2 thrombocytopenia, 3/6 patients with G1/2 anemia, and 1/6 patient with G1/2 neutropenia. Additional G1/2 non-hematologic toxicity included 3/6 patients with diarrhea, 3/6 patients with dyspnea, 3/6 patients with transient elevations in creatinine and 3/6 patients with aspartate aminotransferase elevations.An MTD has not been established and enrollment is ongoing in cohort 2 with carfilzomib at 20/27mg/m2 and ARRY-520 at 1.0 mg/m2. Conclusions:The combination of ARRY-520 and carfilzomib is well tolerated with limited hematologic toxicity and a manageable side effect profile. Notably, in this patient population, with patients who have bortezomib refractory/intolerant myeloma, the combination has demonstrated early signals of activity. Updated safety and efficacy data for all patients will be presented at the meeting. Disclosures:Shah:Onyx: Honoraria, Research Funding, Speakers Bureau; Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Array BioPharma: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Novartis: Honoraria, Research Funding, Speakers Bureau. Off Label Use: This presentation will include information about Arry-520 which is not yet approved for use in patients with multiple myeloma. Wang:Pharmacyclic: Research Funding; onyx: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding. Hilder:Array BioPharma: Employment. Orlowski:onyx: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; array biopharma: Honoraria, Membership on an entity's Board of Directors or advisory committees.

Pomalidomide (CC4047) plus low dose dexamethasone (Pom/dex) is active and well tolerated in lenalidomide refractory multiple myeloma (MM)

Patients with multiple myeloma progressing on current therapies have limited treatment options. Pomalidomide (CC4047), an immunomodulatory drug, has significant activity in relapsed myeloma and previous studies suggest activity in lenalidomide refractory disease. To better define its efficacy in this group, we treated a cohort of lenalidomide refractory patients. Pomalidomide was given orally (2 mg) daily, continuously in 28-day cycles along with dexamethasone (40 mg) given weekly. Responses were assessed by the International Myeloma Working Group Criteria. Thirty-four patients were enrolled. The best response was very good partial response in 3 (9%), partial response (PR) in 8 (23%), best responses (MR) in 5 (15%), stable disease in 12 (35%) and progressive disease in 6 (18%), for an overall response rate of 47%. Of the 14 patients that were considered high risk, 8 (57%) had responses including 4 PR and 4 MR. The median time to response was 2 months and response duration was 9.1 months, respectively. The median overall survival was 13.9 months. Toxicity was primarily hematologic, with grade 3 or 4 toxicity seen in 18 patients (53%) consisting of anemia (12%), thrombocytopenia (9%) and neutropenia (26%). The combination of pomalidomide and dexamethasone (Pom/dex) is highly active and well tolerated in patients with lenalidomide-refractory myeloma.

ASH 2009 meeting report—Top 10 clinically oriented abstracts in multiple myeloma

ASH 2009 meeting report—Top 10 clinically oriented abstracts in multiple myeloma