Belantamab mafodotin in combination with novel agents in relapsed/refractory multiple myeloma: DREAMM-5 study design.

Belantamab mafodotin (belamaf) is a BCMA-targeted antibody-drug conjugate recently approved as monotherapy for adults with relapsed/refractory multiple myeloma who have received ≥4 prior therapies. Belamaf binds to BCMA and eliminates myeloma cells by multimodal mechanisms of action. The cytotoxic and potential immunomodulatory properties of belamaf have led to novel combination studies with other anticancer therapies. Here, we describe the rationale and design of DREAMM-5, an ongoing Phase I/II platform study evaluating the safety and efficacy of belamaf combined with novel agents, including GSK3174998 (OX40 agonist), feladilimab (an ICOS; GSK3359609), nirogacestat (a gamma-secretase inhibitor; PF-03084014) and dostarlimab (a PD-1 blocker) versus belamaf monotherapy for patients with relapsed/refractory multiple myeloma. Clinical trial registration: NCT04126200 (ClinicalTrials.gov).

Phase 1 study of belinostat (PXD-101) and bortezomib (Velcade, PS-341) in patients with relapsed or refractory acute leukemia and myelodysplastic syndrome.

We report the results of a phase 1 dose-escalation study of belinostat and bortezomib in adult patients with acute leukemia or MDS or CML with blast crisis. Thirty-eight patients received IV belinostat days 1-5 and 8-12 with IV bortezomib days 1, 4, 8, and 11 every 21 days. QTc prolongation was the only identified DLT. The RP2Ds were 1.3 mg/m2 bortezomib and 1000 mg/m2 belinostat. One patient with highly refractory MLL-ENL rearranged biphenotypic AML with multiple karyotypic aberrations had a complete pathologic and karyotypic response. One patient with post-MPN AML remained on study with stable disease (SD) for 32 cycles. Whole-exome sequencing revealed no aberrations in the first patient and a hyper-mutator genotype in the second. Eighteen patients had a best response of SD. We conclude that this treatment strategy is feasible but has limited activity in this population. Nevertheless, the factors that predict exceptional responses to this strategy warrant further investigation.

Correction: Synergistic interactions between PLK1 and HDAC inhibitors in non-Hodgkin's lymphoma cells occur in vitro and in vivo and proceed through multiple mechanisms.

[This corrects the article DOI: 10.18632/oncotarget.15649.].

A Phase II Trial of Bortezomib and Vorinostat in Mantle Cell Lymphoma and Diffuse Large B-cell Lymphoma.

BACKGROUND: The proteasome inhibitor bortezomib has demonstrated marked preclinical activity when combined with the histone deacetylase inhibitor vorinostat in leukemia, multiple myeloma, and mantle cell lymphoma (MCL) cells. The present study evaluated the efficacy and safety of the combination in patients with relapsed or refractory MCL and diffuse large B-cell lymphoma (DLBCL). PATIENTS AND METHODS: The present multicenter, nonrandomized phase II trial used a Simon 2-stage design with 3 cohorts: cohort A, MCL with no previous bortezomib (including untreated MCL); cohort B, MCL with previous bortezomib; and cohort C, relapsed or refractory DLBCL with no previous bortezomib. Vorinostat (400 mg) was administered orally on days 1 to 5 and 8 to 12 before bortezomib (1.3 mg/m2), which was administered intravenously on days 1, 4, 8, and 11 of each 21-day cycle. RESULTS: For the 65 treated patients (22 in cohort A, 4 in cohort B, and 39 in cohort C), the overall response rate was 31.8%, 0%, and 7.7%, respectively. The median progression-free survival was 7.6 months for cohort A and 1.8 months for cohort C. In cohort A, 7 patients had a partial response (PRs), 5 had stable disease (SD), 7 had progressive disease (PD), 1 was not assessed, and 2 were not evaluable. In cohort B, 2 had SD and 2 had PD. In cohort C, 3 had a PR, 8 had SD, 23 had PD, and 5 were not assessed. Baseline NF-κB activation, measured as nuclear RelA by immunohistochemistry, did not correlate with clinical response. CONCLUSION: The combination of bortezomib and vorinostat is safe and has modest activity in MCL and limited activity in DLBCL.

Phase 1 trial of ibrutinib and carfilzomib combination therapy for relapsed or relapsed and refractory multiple myeloma.

This phase 1, dose-finding study investigated ibrutinib and carfilzomib ± dexamethasone in patients with relapsed or relapsed/refractory multiple myeloma (≥2 lines of therapy including bortezomib and an immunomodulatory agent). Of 43 patients enrolled, 74% were refractory to bortezomib and 23% had high-risk cytogenetics. No dose-limiting toxicities were observed. The recommended phase 2 dose was ibrutinib 840 mg and carfilzomib 36 mg/m2 with dexamethasone. The most common ≥ grade 3 (>10%) treatment-emergent adverse events were hypertension, anemia, pneumonia, fatigue, diarrhea, and thrombocytopenia. Overall response rate was 67% (very good partial response, 21%; stringent complete response, 2%), with an additional 9% minimal response. Median progression-free survival was 7.2 months and was not inferior in refractory nor high-risk patients. Median overall survival was not reached. Ibrutinib plus carfilzomib demonstrated encouraging responses with a manageable safety profile in this advanced population.

Synergistic interactions between PLK1 and HDAC inhibitors in non-Hodgkin's lymphoma cells occur in vitro and in vivo and proceed through multiple mechanisms.

Interactions between the polo-like kinase 1 (PLK1) inhibitor volasertib and the histone deacetylase inhibitor (HDACI) belinostat were examined in diffuse large B-cell lymphoma (DLBCL) and mantle cell lymphoma (MCL) cells in vitro and in vivo. Exposure of DLBCL cells to very low concentrations of volasertib in combination with belinostat synergistically increased cell death (apoptosis). Similar interactions occurred in GC-, ABC-, double-hit DLBCL cells, MCL cells, bortezomib-resistant cells and primary lymphoma cells. Co-exposure to volasertib/belinostat induced a marked increase in M-phase arrest, phospho-histone H3, mitotic errors, cell death in M-phase, and DNA damage. Belinostat diminished c-Myc mRNA and protein expression, an effect significantly enhanced by volasertib co-exposure. c-Myc knock-down increased DNA damage and cell death in response to volasertib, arguing that c-Myc down-regulation plays a functional role in the lethality of this regimen. Notably, PLK1 knock-down in DLBCL cells significantly increased belinostat-induced M-phase accumulation, phospho-histone H3, γH2AX, and cell death. Co-administration of volasertib and belinostat dramatically reduced tumor growth in an ABC-DLBCL flank model (U2932) and a systemic double-hit lymphoma model (OCI-Ly18), accompanied by a pronounced increase in survival without significant weight loss or other toxicities. Together, these findings indicate that PLK1/HDAC inhibition warrants attention as a therapeutic strategy in NHL.

A phase 1 study of bortezomib and romidepsin in patients with chronic lymphocytic leukemia/small lymphocytic lymphoma, indolent B-cell lymphoma, peripheral T-cell lymphoma, or cutaneous T-cell lymphoma.

A phase 1 study was conducted to determine the dose-limiting toxicities and maximum-tolerated dose (MTD) for bortezomib followed by romidepsin on days 1, 8, and 15 in patients with relapsed/refractory CLL/SLL or B- or T-cell lymphoma. Eighteen treated patients were evaluable for response. The MTD was 1.3 mg/m2 bortezomib and 10 mg/m2 romidepsin; median treatment duration was 3 cycles at this dose. The dose-limiting toxicities were grade 3 fatigue, vomiting, and chills. Two patients had partial responses, one lasting >2 years, 8 had stable disease, and 8 had progressive disease. The median duration of stable disease was 3.5 cycles. Correlative studies examining expression of NF-кB, XIAP, Bcl-xL, and Bim yielded variable results. The safety profile was consistent with that reported for single-agent bortezomib and romidepsin. This regimen has modest activity in heavily pretreated patients with relapsed/refractory CLL or B- or T-cell lymphoma. NCT00963274.

Warfarin improves neuropathy in monoclonal gammopathy of undetermined significance.

We report a case of a 60-year-old man who was referred to a palliative care clinic with monoclonal gammopathy of undetermined significance (MGUS)-associated neuropathy, responding to a therapeutic trial of warfarin. Electromyography showed distal symmetric sensory axonal neuropathy. The patient reported having had improvement of his neuropathic symptoms while taking warfarin postoperatively for thromboprophylaxis 1 year prior, and recurrence of his symptoms after the warfarin was discontinued. The patient was rechallenged with a trial of warfarin, targeting an international normalised ratio of 1.5-2.0. His pain scores decreased from 5/10 to 3/10 at 1 month and symptom improvement was maintained through 24 months of follow-up. Warfarin had a remarkable impact on our patient's symptoms and quality of life. The mechanisms mediating the symptomatic benefit with warfarin are unclear; however, a placebo effect is unlikely. Further studies may help guide the use of warfarin for MGUS-associated neuropathy.

A Phase II Trial of AZD6244 (Selumetinib, ARRY-142886), an Oral MEK1/2 Inhibitor, in Relapsed/Refractory Multiple Myeloma.

PURPOSE: AZD6244 is a MEK1/2 inhibitor with significant preclinical activity in multiple myeloma cells. This phase II study used a two-stage Simon design to determine the AZD6244 response rate in patients with relapsed or refractory multiple myeloma. EXPERIMENTAL DESIGN: AZD6244 (75 mg) was administered orally, twice a day, continuously for 28-day cycles. Response was evaluated after three cycles. RESULTS: Thirty-six patients received therapy. The median age was 65 years (range: 43-81) and the median number of prior therapies was 5 (range: 2-11). The most common grade 3 and 4 toxicities included anemia, neutropenia, thrombocytopenia, diarrhea, and fatigue. Three deaths occurred possibly related to AZD6244 (2 due to sepsis, 1 due to acute kidney injury). After AZD6244 discontinuation, three additional deaths occurred due to disease progression. The response rate (CR + PR) was 5.6% with a mean duration of response of 4.95 months and median progression-free survival time of 3.52 months. One patient had a very good partial response (VGPR), 1 patient had a partial response, 17 patients had stable disease, 13 patients had progressive disease, and 4 patients could not be assessed for response. Pharmacodynamic studies revealed variable effects on bone marrow CD138(+) cell MEK1/2 and ERK1/2 phosphorylation. The best clinical response, a prolonged VGPR, occurred in a patient with an MMSET translocation. CONCLUSIONS: Single-agent AZD6244 was tolerable and had minimal activity in this heavily pretreated population.

Phase 1 trial of carfilzomib (PR-171) in combination with vorinostat (SAHA) in patients with relapsed or refractory B-cell lymphomas.

A phase 1 study with carfilzomib and vorinostat was conducted in 20 B-cell lymphoma patients. Vorinostat was given orally twice daily on days 1, 2, 3, 8, 9, 10, 15, 16, and 17 followed by carfilzomib (given as a 30-min infusion) on days 1, 2, 8, 9, 15, and 16. A treatment cycle was 28 days. Dose escalation initially followed a standard 3 + 3 design, but adapted a more conservative accrual rule following dose de-escalation. The maximum tolerated dose was 20 mg/m2 carfilzomib and 100 mg vorinostat (twice daily). The dose-limiting toxicities were grade 3 pneumonitis, hyponatremia, and febrile neutropenia. One patient had a partial response and two patients had stable disease. Correlative studies showed a decrease in NF-κB activation and an increase in Bim levels in some patients, but these changes did not correlate with clinical response.

Phase 2 study of frontline brentuximab vedotin monotherapy in Hodgkin lymphoma patients aged 60 years and older.

Outcomes in older patients with Hodgkin lymphoma (HL) tend to be poor following conventional chemotherapy regimens. Treatment-related toxicity is significant and comorbidities often limit therapeutic options. This phase 2, open-label study evaluated the efficacy and safety of brentuximab vedotin, a CD30-directed antibody-drug conjugate, as frontline therapy in 27 HL patients aged ≥60 years. The objective response rate (ORR) was 92%, with 73% achieving complete remission. All patients achieved stable disease or better, and had decreased tumor volume following treatment. At the time of this analysis, the median duration of objective response for efficacy-evaluable patients (N = 26) was 9.1 months (range, 2.8 to 20.9+ months), median progression-free survival was 10.5 months (range, 2.6+ to 22.3+ months), and median overall survival had not been reached (range, 4.6+ to 24.9+ months). The observed adverse events (AEs) were generally consistent with the known safety profile of brentuximab vedotin. The most common AEs were peripheral sensory neuropathy (78%), fatigue (44%), and nausea (44%), and were ≤ grade 2 for most patients. The incidence of grade 3 peripheral neuropathy events was relatively high (30% overall), particularly among patients with the known risk factors of diabetes and/or hypothyroidism (46% vs 14% for those without). However, these risk factors were not associated with delayed time to resolution/improvement of peripheral neuropathy. Preliminary data showed no substantial age-related changes in brentuximab vedotin pharmacokinetics. Brentuximab vedotin monotherapy may provide a frontline treatment option for older patients who cannot tolerate conventional combination chemotherapy. This trial was registered at www.clinicaltrials.gov as #NCT01716806.

A Phase II Study of Sorafenib Combined With Cetuximab in EGFR-Expressing, KRAS-Mutated Metastatic Colorectal Cancer.

BACKGROUND: Mutations in the KRAS gene predict for resistance to anti-epidermal growth factor receptor (EGFR) therapies, including cetuximab. Upregulation of vascular endothelial growth factor (VEGF)-A has been implicated in resistance to anti-EGFR treatment. Abrogation of the VEGF and RAS/RAF/MEK/ERK pathways has the potential to restore cetuximab sensitivity. PATIENTS AND METHODS: Adult patients with histologically documented, measurable, EGFR-expressing, KRAS-mutated metastatic colorectal cancer (mCRC) that had progressed after 5-fluorouracil-based regimens were treated with sorafenib 400 mg orally twice daily and intravenous cetuximab weekly in 28-day cycles. The primary endpoint was the response rate (complete response, partial response, and stable disease at 4 cycles). The secondary endpoints included plasma biomarker analysis of angiogenic cytokines and correlative imaging studies with dynamic contrast-enhanced magnetic resonance imaging and zirconium 89-panitumumab. RESULTS: Of the 30 patients enrolled, 26 were evaluable for response. Of the 26 patients evaluated, 4 had stable disease at 4 cycles and 1 had stable disease at 8 cycles. The median progression-free survival was 1.84 months. The common toxicities were rash, diarrhea, and liver enzyme elevations. Of the angiogenic cytokines evaluated, only the placental growth factor increased significantly with treatment (P < .0001). No pharmacodynamic parameters were associated with the treatment response. CONCLUSION: We report the results of a trial that combined cetuximab and sorafenib for the treatment of KRAS-mutated mCRC, with correlative imaging studies and pharmacodynamic angiogenic cytokine profiling as downstream markers of EGFR and VEGF receptor (VEGFR) signaling. No objective responses were observed. Additional development of biomarkers for patient selection is needed to evaluate combined EGFR and VEGFR blockade as a therapeutic option in KRAS-mutated CRC.

Phase I trial of bortezomib (PS-341; NSC 681239) and "nonhybrid" (bolus) infusion schedule of alvocidib (flavopiridol; NSC 649890) in patients with recurrent or refractory indolent B-cell neoplasms.

PURPOSE: This phase I study was conducted to determine the dose-limiting toxicities (DLT) and maximum tolerated dose (MTD) for the combination of bortezomib and alvocidib in patients with B-cell malignancies (multiple myeloma, indolent lymphoma, Waldenstrom macroglobulinemia, and mantle cell lymphoma). EXPERIMENTAL DESIGN: Patients received bortezomib (intravenous push), followed by alvocidib (1-hour infusion), on days 1, 4, 8, and 11 of a 21-day treatment cycle. Patients experiencing responses or stable disease continued on treatment at the investigator's discretion. A standard 3+3 dose-escalation design was used to identify the MTD based on DLTs, and pharmacokinetic and pharmacodynamic studies were conducted. RESULTS: A total of 44 patients were enrolled, with 39 patients assessed for response. The MTD was established as 1.3 mg/m(2) for bortezomib and 40 mg/m(2) for alvocidib. The most common hematologic toxicities included leukopenia, lymphopenia, neutropenia, and thrombocytopenia. The most common nonhematologic toxicities included diarrhea, fatigue, and sensory neuropathy. Three complete remissions (8%) and 10 partial remissions (26%) were observed for a total response rate of 33%. Pharmacokinetic findings with the current dosing regimen were consistent with the comparable literature and the hybrid dosing regimen. Pharmacodynamic study results did not correlate with clinical responses. CONCLUSIONS: The combination of bortezomib and alvocidib is tolerable, and an MTD has been established for this schedule. The regimen appears to be efficacious in patients with relapsed/refractory multiple myeloma or indolent non-Hodgkin lymphoma. As the nonhybrid regimen is less cumbersome than the previous hybrid dosing schedule regimen, the current schedule is recommended for successor studies.

Bortezomib for the treatment of non-Hodgkin's lymphoma.

INTRODUCTION: Bortezomib , the first proteasome inhibitor (PI) to be evaluated in humans, is approved in the USA and Europe for the treatment of patients with multiple myeloma, and in the USA for patients with relapsed mantle cell lymphoma (MCL). AREAS COVERED: This review examines the role of bortezomib in the therapy of non-Hodgkin's lymphoma (NHL). Bortezomib may be particularly effective against the NF-κB-dependent activated B-cell subtype of diffuse large B-cell lymphoma. The combination of bortezomib with rituximab and dexamethasone represents a standard approach for the treatment of Waldenström's macroglobulinemia, and that with bendamustine and rituximab has demonstrated excellent efficacy in follicular lymphoma. Combinations with other novel agents, such as inhibitors of cyclin-dependent kinases or histone deacetylases, also hold substantial promise in NHL. Unmet needs in NHL, competitor compounds, chemistry, pharmacokinetics, pharmacodynamics and safety and tolerability of bortezomib are also discussed. EXPERT OPINION: The success of bortezomib in MCL has validated the proteasome as a therapeutic target in NHL. Rational combinations, for example, with Bruton's tyrosine kinase inhibitors or BH3-mimetics, may hold the key to optimizing the therapeutic potential of PIs in NHL. Future trials are likely to involve newer agents with improved pharmacodynamic (e.g., carfilzomib, marizomib) or pharmacokinetic (e.g., ixazomib, oprozomib) properties.

A phase I trial of vorinostat and alvocidib in patients with relapsed, refractory, or poor prognosis acute leukemia, or refractory anemia with excess blasts-2.

PURPOSE: This phase I study was conducted to identify the maximum-tolerated dose (MTD) of alvocidib when combined with vorinostat in patients with relapsed, refractory, or poor prognosis acute leukemia, or refractory anemia with excess blasts-2. Secondary objectives included investigating the pharmacokinetic and pharmacodynamic effects of the combination. EXPERIMENTAL DESIGN: Patients received vorinostat (200 mg orally, three times a day, for 14 days) on a 21-day cycle, combined with 2 different alvocidib administration schedules: a 1-hour intravenous infusion, daily × 5; or a 30-minute loading infusion followed by a 4-hour maintenance infusion, weekly × 2. The alvocidib dose was escalated using a standard 3+3 design. RESULTS: Twenty-eight patients were enrolled and treated. The alvocidib MTD was 20 mg/m(2) (30-minute loading infusion) followed by 20 mg/m(2) (4-hour maintenance infusion) on days one and eight, in combination with vorinostat. The most frequently encountered toxicities were cytopenias, fatigue, hyperglycemia, hypokalemia, hypophosphatemia, and QT prolongation. Dose-limiting toxicities (DLT) were cardiac arrhythmia-atrial fibrillation and QT prolongation. No objective responses were achieved although 13 of 26 evaluable patients exhibited stable disease. Alvocidib seemed to alter vorinostat pharmacokinetics, whereas alvocidib pharmacokinetics were unaffected by vorinostat. Ex vivo exposure of leukemia cells to plasma obtained from patients after alvocidib treatment blocked vorinostat-mediated p21(CIP1) induction and downregulated Mcl-1 and p-RNA Pol II for some specimens, although parallel in vivo bone marrow responses were infrequent. CONCLUSIONS: Alvocidib combined with vorinostat is well tolerated. Although disease stabilization occurred in some heavily pretreated patients, objective responses were not obtained with these schedules.

Proteasome inhibitors in mantle cell lymphoma.

Mantle cell lymphoma (MCL) represents a subtype of non-Hodgkin's lymphoma (NHL) which has a relatively poor prognosis compared to other forms of NHL. Despite multiple options for cytotoxic chemotherapy, attempts to prolong the survival of patients with this disease have not yet met with success. Consequently, the development of targeted approaches to therapy which minimize toxicities has potentially important implications for MCL. Proteasome inhibitors preferentially kill transformed cells through diverse mechanisms. The proteasome inhibitor bortezomib was initially approved for patients with relapsed or refractory multiple myeloma and now has been approved for relapsed or refractory MCL. The introduction of newer proteasome inhibitors with activity in bortezomib-resistant disease and reduced toxicity profiles may yield further benefits. Multiple ongoing studies are building on the known efficacy of proteasome inhibitors in MCL by evaluating combination regimens involving either cytotoxic or targeted therapies, with the ultimate goal of prolonging survival in this patient population.

Phase I trial of bortezomib (PS-341; NSC 681239) and alvocidib (flavopiridol; NSC 649890) in patients with recurrent or refractory B-cell neoplasms.

PURPOSE: A phase I study was conducted to determine the dose-limiting toxicities (DLT) and maximum tolerated dose (MTD) for the combination of bortezomib and alvocidib in patients with B-cell malignancies (multiple myeloma, indolent lymphoma, and mantle cell lymphoma). EXPERIMENTAL DESIGN: Patients received bortezomib by intravenous push on days 1, 4, 8, and 11. Patients also received alvocidib on days 1 and 8 by 30-minute bolus infusion followed by a 4-hour continuous infusion. Treatment was on a 21-day cycle, with indefinite continuation for patients experiencing responses or stable disease. Dose escalation employed a standard 3 + 3 design until the MTD was identified on the basis of DLTs. Pharmacokinetic studies and pharmacodynamic studies were conducted. RESULTS: Sixteen patients were treated. The MTD was established as 1.3 mg/m(2) for bortezomib and 30 mg/m(2) for alvocidib (both the 30-minute bolus and 4-hour infusions). Common hematologic toxicities included leukopenia, lymphopenia, neutropenia, and thrombocytopenia. Common nonhematologic toxicities included fatigue and febrile neutropenia. DLTs included fatigue, febrile neutropenia, and elevated aspartate aminotransferase (AST) levels. Two complete responses (CR; 12%) and five partial responses (PR; 31%) were observed at the MTD (overall response rate = 44%). Pharmacokinetic results were typical for alvocidib and pharmacodynamic studies yielded variable results. CONCLUSIONS: The combination of bortezomib and alvocidib is tolerable and an MTD has been established for the tested schedule. The regimen appears active in patients with relapsed and/or refractory multiple myeloma or non-Hodgkin's lymphoma, justifying phase II studies to determine the activity of this regimen more definitively.