Jonathan L. Kaufman

Lenalidomide, bortezomib, and dexamethasone combination therapy in patients with newly diagnosed multiple myeloma.

This phase 1/2 study is the first prospective evaluation of lenalidomide-bortezomib-dexamethasone in front-line myeloma. Patients (N = 66) received 3-week cycles (n = 8) of bortezomib 1.0 or 1.3 mg/m(2) (days 1, 4, 8, 11), lenalidomide 15 to 25 mg (days 1-14), and dexamethasone 40 or 20 mg (days 1, 2, 4, 5, 8, 9, 11, 12). Responding patients proceeded to maintenance or transplantation. Phase 2 dosing was determined to be bortezomib 1.3 mg/m(2), lenalidomide 25 mg, and dexamethasone 20 mg. Most common toxicities included sensory neuropathy (80%) and fatigue (64%), with only 27%/2% and 32%/3% grade 2/3, respectively. In addition, 32% reported neuropathic pain (11%/3%, grade 2/3). Grade 3/4 hematologic toxicities included lymphopenia (14%), neutropenia (9%), and thrombocytopenia (6%). Thrombosis was rare (6% overall), and no treatment-related mortality was observed. Rate of partial response was 100% in both the phase 2 population and overall, with 74% and 67% each achieving very good partial response or better. Twenty-eight patients (42%) proceeded to undergo transplantation. With median follow-up of 21 months, estimated 18-month progression-free and overall survival for the combination treatment with/without transplantation were 75% and 97%, respectively. Lenalidomide-bortezomib-dexamethasone demonstrates favorable tolerability and is highly effective in the treatment of newly diagnosed myeloma. This study is registered at http://clinicaltrials.gov as NCT00378105.

Plerixafor and G-CSF versus placebo and G-CSF to mobilize hematopoietic stem cells for autologous stem cell transplantation in patients with multiple myeloma.

This phase 3, multicenter, randomized (1:1), double-blind, placebo-controlled study evaluated the safety and efficacy of plerixafor with granulocyte colony-stimulating factor (G-CSF) in mobilizing hematopoietic stem cells in patients with multiple myeloma. Patients received G-CSF (10 microg/kg) subcutaneously daily for up to 8 days. Beginning on day 4 and continuing daily for up to 4 days, patients received either plerixafor (240 microg/kg) or placebo subcutaneously. Starting on day 5, patients began daily apheresis for up to 4 days or until more than or equal to 6 x 10(6) CD34(+) cells/kg were collected. The primary endpoint was the percentage of patients who collected more than or equal to 6 x 10(6) CD34(+) cells/kg in less than or equal to 2 aphereses. A total of 106 of 148 (71.6%) patients in the plerixafor group and 53 of 154 (34.4%) patients in the placebo group met the primary endpoint (P < .001). A total of 54% of plerixafor-treated patients reached target after one apheresis, whereas 56% of the placebo-treated patients required 4 aphereses to reach target. The most common adverse events related to plerixafor were gastrointestinal disorders and injection site reactions. Plerixafor and G-CSF were well tolerated, and significantly more patients collected the optimal CD34(+) cell/kg target for transplantation earlier compared with G-CSF alone. This study is registered at www.clinicaltrials.gov as #NCT00103662.

Tyrosine phosphorylation inhibits PKM2 to promote the Warburg effect and tumor growth

Tyrosine phosphorylation of pyruvate kinase M2 gives tumor cells a metabolic advantage. A Malignant Metabolic Switch Cancer cells show aberrant metabolism, consuming more glucose than do healthy cells and producing lactate even in the presence of abundant oxygen, rather than shifting to oxidative phosphorylation. This phenomenon is called the Warburg effect, after Otto Warburg, who described it many years ago. Building on recent research implicating inhibition of the M2 isoform of the glycolytic enzyme pyruvate kinase (PKM2) by phosphotyrosine binding as critical to the Warburg effect—and tumorigenesis—Hitosugi et al. explored the role of signaling from oncogenic forms of the fibroblast growth factor receptor type 1 (FGFR1) in mediating this metabolic switch. They found that FGFR1, a receptor tyrosine kinase, phosphorylated a tyrosine residue (Y105) on PKM2 itself. Further analysis revealed that this tyrosine residue was commonly phosphorylated in human cancers and that a mutant form of PKM2 lacking this tyrosine residue inhibited both “Warburg metabolism” and tumor growth. They thus propose that phosphorylation of PKM2 by oncogenic tyrosine kinases provides the very phosphotyrosine that binds to and inhibits PKM2 to induce the Warburg effect and promote tumor growth. The Warburg effect describes a pro-oncogenic metabolism switch such that cancer cells take up more glucose than normal tissue and favor incomplete oxidation of glucose even in the presence of oxygen. To better understand how tyrosine kinase signaling, which is commonly increased in tumors, regulates the Warburg effect, we performed phosphoproteomic studies. We found that oncogenic forms of fibroblast growth factor receptor type 1 inhibit the pyruvate kinase M2 (PKM2) isoform by direct phosphorylation of PKM2 tyrosine residue 105 (Y105). This inhibits the formation of active, tetrameric PKM2 by disrupting binding of the PKM2 cofactor fructose-1,6-bisphosphate. Furthermore, we found that phosphorylation of PKM2 Y105 is common in human cancers. The presence of a PKM2 mutant in which phenylalanine is substituted for Y105 (Y105F) in cancer cells leads to decreased cell proliferation under hypoxic conditions, increased oxidative phosphorylation with reduced lactate production, and reduced tumor growth in xenografts in nude mice. Our findings suggest that tyrosine phosphorylation regulates PKM2 to provide a metabolic advantage to tumor cells, thereby promoting tumor growth.

Widespread Genetic Heterogeneity in Multiple Myeloma: Implications for Targeted Therapy

We performed massively parallel sequencing of paired tumor/normal samples from 203 multiple myeloma (MM) patients and identified significantly mutated genes and copy number alterations and discovered putative tumor suppressor genes by determining homozygous deletions and loss of heterozygosity. We observed frequent mutations in KRAS (particularly in previously treated patients), NRAS, BRAF, FAM46C, TP53, and DIS3 (particularly in nonhyperdiploid MM). Mutations were often present in subclonal populations, and multiple mutations within the same pathway (e.g., KRAS, NRAS, and BRAF) were observed in the same patient. In vitro modeling predicts only partial treatment efficacy of targeting subclonal mutations, and even growth promotion of nonmutated subclones in some cases. These results emphasize the importance of heterogeneity analysis for treatment decisions.

Elotuzumab in Combination With Lenalidomide and Low-Dose Dexamethasone in Relapsed or Refractory Multiple Myeloma

PURPOSE This phase I study evaluated elotuzumab, lenalidomide, and dexamethasone in patients with relapsed or refractory multiple myeloma (MM). PATIENTS AND METHODS Three cohorts were enrolled and treated with elotuzumab (5.0, 10, or 20 mg/kg intravenously) on days 1, 8, 15, and 22 of a 28-day cycle in the first two cycles, and days 1 and 15 of each subsequent cycle; lenalidomide 25 mg orally [PO] on days 1 to 21; and dexamethasone 40 mg PO weekly. Dose-limiting toxicities (DLTs) were assessed during cycle 1 of each cohort, and clinical responses were evaluated during each cycle. The first five patients received up to six cycles of therapy; subsequent patients were treated until disease progression. RESULTS Twenty-nine patients with advanced MM and a median of three prior MM therapies were enrolled; 28 patients were treated, three each in the 5.0-mg/kg and 10-mg/kg cohorts and 22 in the 20-mg/kg cohort. No DLTs were observed up to the maximum proposed dose of 20 mg/kg. The most frequent grade 3 to 4 toxicities were neutropenia (36%) and thrombocytopenia (21%). Two patients experienced a serious infusion reaction (one grade 4 anaphylactic reaction and one grade 3 stridor) during the first treatment cycle. Objective responses were obtained in 82% (23 of 28) of treated patients. After a median of 16.4 months follow-up, the median time to progression was not reached for patients in the 20-mg/kg cohort who were treated until disease progression. CONCLUSION The combination of elotuzumab, lenalidomide, and low-dose dexamethasone was generally well tolerated and showed encouraging response rates in patients with relapsed or refractory MM.

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.

Safety and tolerability of ixazomib, an oral proteasome inhibitor, in combination with lenalidomide and dexamethasone in patients with previously untreated multiple myeloma: an open-label phase 1/2 study

BACKGROUND The combination of bortezomib, lenalidomide, and dexamethasone is a highly effective therapy for newly diagnosed multiple myeloma. Ixazomib is an investigational, oral, proteasome inhibitor with promising anti-myeloma effects and low rates of peripheral neuropathy. In a phase 1/2 trial we aimed to assess the safety, tolerability, and activity of ixazomib in combination with lenalidomide and dexamethasone in newly diagnosed multiple myeloma. METHODS We enrolled patients newly diagnosed with multiple myeloma aged 18 years or older with measurable disease, Eastern Cooperative Oncology Group performance status 0-2, and no grade 2 or higher peripheral neuropathy, and treated them with oral ixazomib (days 1, 8, 15) plus lenalidomide 25 mg (days 1-21) and dexamethasone 40 mg (days 1, 8, 15, 22) for up to 12 28-day cycles, followed by maintenance therapy with ixazomib alone. In phase 1, we gave patients escalating doses of ixazomib (1·68-3·95 mg/m(2)) to establish the recommended dose for phase 2. The primary endpoints were maximum tolerated dose for phase 1, and the rate of very good partial response or better for phase 2. Safety analyses were done in all patients who received at least one dose of study drug; efficacy analyses were done in all patients who received at least one dose of study drug at the phase 2 dose, had measurable disease at baseline, and had at least one post-baseline response assessment. This study is registered at ClinicalTrials.gov, number NCT01217957. FINDINGS Between Nov 22, 2010, and Feb 28, 2012, we enrolled 65 patients (15 to phase 1 and 50 to phase 2). Four dose-limiting toxic events were noted in phase 1: one at a dose of ixazomib of 2·97 mg/m(2) and three at 3·95 mg/m(2). The maximum tolerated dose of ixazomib was established as 2·97 mg/m(2) and the recommended phase 2 dose was 2·23 mg/m(2), which was converted to a 4·0 mg fixed dose based on population pharmacokinetic results. Grade 3 or higher adverse events related to any drug were reported in 41 (63%) patients, including skin and subcutaneous tissue disorders (11 patients, 17%), neutropenia (eight patients, 12%), and thrombocytopenia (five patients, 8%); drug-related peripheral neuropathy of grade 3 or higher occurred in four (6%) patients. Five patients discontinued because of adverse events. In 64 response-evaluable patients, 37 (58%, 95% CI 45-70) had a very good partial response or better. INTERPRETATION The all-oral combination of weekly ixazomib plus lenalidomide and dexamethasone was generally well tolerated and appeared active in newly diagnosed multiple myeloma. These results support the phase 3 trial development of this combination for multiple myeloma. FUNDING Millennium Pharmaceuticals, a wholly owned subsidiary of Takeda Pharmaceutical International Company.

A phase 2 trial of lenalidomide, bortezomib, and dexamethasone in patients with relapsed and relapsed/refractory myeloma

In this prospective, multicenter, phase 2 study, 64 patients with relapsed or relapsed and refractory multiple myeloma (MM) received up to 8 21-day cycles of bortezomib 1.0 mg/m(2) (days 1, 4, 8, and 11), lenalidomide 15 mg/day (days 1-14), and dexamethasone 40/20 mg/day (cycles 1-4) and 20/10 mg/day (cycles 5-8) (days of/after bortezomib dosing). Responding patients could receive maintenance therapy. Median age was 65 years; 66% were male, 58% had relapsed and 42% had relapsed and refractory MM, and 53%, 75%, and 6% had received prior bortezomib, thalidomide, and lenalidomide, respectively. Forty-eight of 64 patients (75%; 90% confidence interval, 65-84) were alive without progressive disease at 6 months (primary end point). The rate of partial response or better was 64%; median duration of response was 8.7 months. Median progression-free and overall survivals were 9.5 and 30 months, respectively (median follow-up: 44 months). Common treatment-related toxicities included sensory neuropathy (53%), fatigue (50%), and neutropenia (42%); common grade 3/4 treatment-related toxicities included neutropenia (30%), thrombocytopenia (22%), and lymphopenia (11%). Grade 3 motor neuropathy was reported in 2 patients. Lenalidomide-bortezomib-dexamethasone appears effective and tolerable in patients with relapsed or relapsed and refractory MM, demonstrating substantial activity among patients with diverse prior therapies and adverse prognostic characteristics. This trial is registered with www.clinicaltrials.gov as #NCT00378209.

Carfilzomib, pomalidomide, and dexamethasone for relapsed or refractory myeloma

Treatment options for patients with heavily pretreated relapsed and/or refractory multiple myeloma remain limited. We evaluated a novel therapeutic regimen consisting of carfilzomib, pomalidomide, and dexamethasone (CPD) in an open-label, multicenter, phase 1, dose-escalation study. Patients who relapsed after prior therapy or were refractory to the most recently received therapy were eligible. All patients were refractory to prior lenalidomide. Patients received carfilzomib IV on days 1, 2, 8, 9, 15, and 16 (starting dose of 20/27 mg/m(2)), pomalidomide once daily on days 1 to 21 (4 mg as the initial dose level), and dexamethasone (40 mg oral or IV) on days 1, 8, 15, and 22 of 28-day cycles. The primary objective was to evaluate the safety and determine the maximum tolerated dose (MTD) of the regimen. A total of 32 patients were enrolled. The MTD of the regimen was dose level 1 (carfilzomib 20/27 mg/m(2), pomalidomide 4 mg, dexamethasone 40 mg). Hematologic adverse events (AEs) occurred in ≥60% of all patients, including 11 patients with grade ≥3 anemia. Dyspnea was limited to grade 1/2 in 10 patients. Peripheral neuropathy was uncommon and limited to grade 1/2. Eight patients had dose reductions during therapy, and 7 patients discontinued treatment due to AEs. Two deaths were noted on study due to pneumonia and pulmonary embolism (n = 1 each). The combination of CPD is well-tolerated and highly active in patients with relapsed/refractory multiple myeloma. This trial was registered at www.clinicaltrials.gov as #NCT01464034.

Safety and Clinical Activity of a Combination Therapy Comprising Two Antibody-Based Targeting Agents for the Treatment of Non-Hodgkin Lymphoma: Results of a Phase I/II Study Evaluating the Immunoconjugate Inotuzumab Ozogamicin With Rituximab

PURPOSE Inotuzumab ozogamicin (INO) is an antibody-targeted chemotherapy agent composed of a humanized anti-CD22 antibody conjugated to calicheamicin, a potent cytotoxic agent. We performed a phase I/II study to determine the maximum-tolerated dose (MTD), safety, efficacy, and pharmacokinetics of INO plus rituximab (R-INO) for treatment of relapsed/refractory CD20(+)/CD22(+) B-cell non-Hodgkin lymphoma (NHL). PATIENTS AND METHODS A dose-escalation phase to determine the MTD of R-INO was followed by an expanded cohort to further evaluate the efficacy and safety at the MTD. Patients with relapsed follicular lymphoma (FL), relapsed diffuse large B-cell lymphoma (DLBCL), or refractory aggressive NHL received R-INO every 4 weeks for up to eight cycles. RESULTS In all, 118 patients received one or more cycles of R-INO (median, four cycles). Most common grade 3 to 4 adverse events were thrombocytopenia (31%) and neutropenia (22%). Common low-grade toxicities included hyperbilirubinemia (25%) and increased AST (36%). The MTD of INO in combination with rituximab (375 mg/m(2)) was confirmed to be the same as that for single-agent INO (1.8 mg/m(2)). Treatment at the MTD yielded objective response rates of 87%, 74%, and 20% for relapsed FL (n = 39), relapsed DLBCL (n = 42), and refractory aggressive NHL (n = 30), respectively. The 2-year progression-free survival (PFS) rate was 68% (median, not reached) for FL and 42% (median, 17.1 months) for relapsed DLBCL. CONCLUSION R-INO demonstrated high response rates and long PFS in patients with relapsed FL or DLBCL. This and the manageable toxicity profile suggest that R-INO may be a promising option for CD20(+)/CD22(+) B-cell NHL.