Efficacy Of Carfilzomib Research Articles

Spheroid culture to select theoretical therapeutic drugs in intravascular large B-cell lymphoma.

Intravascular large B-cell lymphoma (IVLBCL) is a rare type of extranodal large B-cell lymphoma that is characterized by the proliferation of lymphoma cells in the lumina of small vessels. Recent progress uncovering the genetic characteristics associated with MYD88/CD79B mutations has stimulated interest in the use of drugs targeting B-cell receptor signaling, including Bruton's tyrosine kinase. However, difficulties in culturing exvivo IVLBCL cells has hampered research on the development of novel therapies. In the present study, we demonstrated the establishment of an exvivo culture system of IVLBCL cells obtained from patient-derived xenograft (PDX) models. The spheroid culture enabled us to culture IVLBCL PDX cells for more than 10 days and to explore the efficacy of drug treatments acting on these cells. We found that carfilzomib and ibrutinib were effective for treating IVLBCL in exvivo experiments and conducted invivo analyses to assess the efficacy of these drugs. Although the efficacy of carfilzomib was difficult to confirm due to its toxicity in our models, ibrutinib showed comparable efficacy to a standard combination of chemotherapy drugs. Together, our data provide a new culture method for IVLBCL PDX cells and a rationale for translating ibrutinib to clinical use in IVLBCL patients.

Real-life effectiveness of carfilzomib in patients with relapsed multiple myeloma receiving treatment in the context of early access: The CARMYN study.

The real-life retrospective observational study CARMYN aimed at investigating the long-term efficacy and safety of carfilzomib in combination with dexamethasone and lenalidomide (KRd, 159 patients). These patients (62% in first and 38% in second relapse, median age 62 yo) were treated between 02/2014 and 02/2017. Most had been pre-exposed to bortezomib (98.2%) and to an IMID (75.4%). At the time of collection, 90% had permanently discontinued carfilzomib. Data collection was conducted from January to July 2021 in 27 participating sites, after a median of 39 months follow-up. For patients treated with KRd, an overall response rate of 78.4% translated in a median progression free survival (PFS) of 24.0 months (95% CI 18.8-27.6) and a median overall survival (OS) of 51.1 months (95% CI 41.3-not reached). Results were poorer but difficult to interpret in the small cohort of Kd recipients. The study is one of the longest real-life studies of carfilzomib treatment in patients in first or second relapse. CARMYN confirmed the real-life long-term efficacy of carfilzomib in combination with lenalidomide and dexamethasone with results similar to those of clinical trials. The KRd regimen is thus an option to consider for late relapses in the current context of MM management.

Abstract 1398: Impact of proteasome inhibitor specificity and efficacy on apoptosis induction by combination with ABT-199

Abstract Metastatic Soft-Tissue Sarcomas (STS) are a rare and highly heterogeneous group of mesenchymal malignancies that carry a poor prognosis. Therapy is hampered by a limited number of effective treatments, and the almost non-existing long-term survival rate illustrates the need of effective targeted treatment. As a potential approach, we investigated combination of the clinically approved BH3-mimetic drug ABT-199 with different proteasome inhibitors (PIs): Bortezomib, Carfilzomib and Ixazomib, each with proven efficacy, e.g., in multiple myeloma. ABT-199 selectively inhibits the anti-apoptotic protein Bcl-2 while Bortezomib (BOZ) and Ixazomib (IXZ) bind reversible to the β1 and β5 subunits of the 20S proteasome and Carfilzomib (CFZ) irreversibly blocks the subunits β2 and β5. We investigated whether the combination of ABT-199 with CFZ or IXZ shows synergistic activity as recently published for BOZ. SW982 sarcoma cells were cultured with PIs alone or in combination with ABT-199. Cell death was detected by flow cytometric analysis of mitochondrial membrane potential (TMRM) and exposure of phosphatidyl serine (Annexin V). To elucidate potential differences due to specificity of PIs, we analyzed expression of BCL-2 family proteins by Western Blot and performed analogue experiments in knock-out (BAXKO, BAKKO, BOKKO) cell lines. In combination, ABT-199&BOZ or ABT-199&CFZ showed comparable synergistic cell death induction in SW982 while ABT-199&IXZ less efficiently induced cell death. Engineered SW982 knock-out cell lines suggests specific relevance of BOK in IXZ induced apoptosis, whereas all tested PIs crucially depend on BAX for apoptosis induction in combination with ABT-199. Also, as shown for ABT-199&BOZ, both CFZ and IXZ, alone and in combination with ABT-199, efficiently induced expression of NOXA. Strikingly, and in line with augmented cell death induction, ABT-199&CFZ resulted in highest expression of NOXA as compared to BOZ and IXZ. ABT-199&PIs synergistically induce apoptotic cell death in SW982 and corresponding knock-out cell lines with CFZ showing exacerbated expression of NOXA. ABT-199&CFZ also induced strongest stabilization of p53, a transcriptional key regulator of NOXA. We suggest that simultaneous inhibition of anti-apoptotic BCL-2 by ABT-199 and the enhanced expression of NOXA double-hit on the BCL-2 and the MCL-1 signaling axis force the cells over the threshold of apoptosis. Enhanced efficacy of CFZ is dually caused by reduced degradation of NOXA and enhanced stabilization of p53, which in turn transactivates expression of NOXA. In conclusion, PI specificity and efficacy modulate apoptosis induction by combination with ABT-199. Future efforts, e.g. knock-out of relevant BH3-only proteins, will elucidate the observed variable efficacy of these and other PIs for prospective translation in clinical applications. Citation Format: Sandra Weller, Benjamin Schaefer, Tobias Beigl, Kathrin Böpple, Walter E. Aulitzky, Hans-Georg Kopp, Frank Essmann. Impact of proteasome inhibitor specificity and efficacy on apoptosis induction by combination with ABT-199 [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 1398.

An Open-Label Phase I/II Study of Carfilzomib, Bendamustine and Dexamethasone (CBD) in Newly Diagnosed Multiple Myeloma Patients

BackgroundCarfilzomib is an irreversible epoxyketone proteasome inhibitor which has demonstrated superior disease control and PFS for myeloma compared to bortezomib. Bendamustine is a bifunctional alkylating agent with demonstrated activity in relapsed/refractory myeloma. We hypothesized that the combination of carfilzomib and bendamustine may result in additive and synergistic effects, without excessive toxicity. In this phase I/II study, we investigate the safety and efficacy of carfilzomib, bendamustine and dexamethasone (CBD) for newly diagnosed myeloma.ObjectivesThe primary objective is to determine the maximum tolerated dose (MTD) of carfilzomib in combination with bendamustine and dexamethasone. Secondary endpoints include overall response rate (ORR), duration of response (DOR), progression free survival (PFS), overall survival (OS), and assessment of stem cell collection.MethodsPatients with newly diagnosed myeloma were enrolled. Carfilzomib was administered intravenously on days 1, 2, 8, 9, 15, 16 of a 28-day cycle. Bendamustine was given intravenously on days 1 and 2. Dexamethasone was administered orally or intravenously on days of carfilzomib and on day 22 of each cycle. The dose escalation portion of the study used an Up-and-Down dose escalation scheme (Storer's schema D), with one patient per dose level run in. Transplant eligible patients received 4 cycles of treatment and then underwent peripheral blood stem cell harvest (SCH) after mobilization with granulocyte-stimulating factor +/- plerixafor. They then received an additional 4 cycles and underwent stem cell transplant (SCT) after 8 total cycles of CBD. Transplant ineligible patients also received 8 total cycles of treatment. Both groups then received maintenance therapy with carfilzomib 36 mg/m2 on days 1, 2, 15, 16 of each 28-day cycle for up to 2 years. Adverse events were assessed according to CTCAE V4 and responses were assessed using IMWG criteria.ResultsAt 38 months into the study, 15 patients have been treated, amongst which 14 were evaluable for response. Median age was 65 (range: 51-74); 10/15 (67%) were male; 6 (40%) were Hispanic, 6 Caucasian, 2 (13%) Asian and 1 (7%) African American. Four patients were allocated to lower level doses and 11 patients thus far have been given the maximum planned dose - carfilzomib 56 mg/m2, bendamustine 90 mg/m2, dexamethasone 20 mg. No dose-limiting toxicities have been noted and the most common adverse events (AEs) are shown in Table 1. Hematologic AEs were most common, occurring in 9 (64%) patients, and Grade 3 or 4 events occurring in 7 (50%). Other notable AEs included Grade 1 or 2 fever (50%), Grade 1 or 2 headache (43%) and thromboembolic events (29%). There were no deaths. No congestive heart failure or arrhythmias were noted. 11 patients underwent stem cell collection, with data available for 10. Median total stem cell yield, in million CD34/kg, was 6.85 (range 5.44-13.83). Median day 1 stem cell yield was 4.43 (range 1.28-13.83). 5 patients received plerixafor. 5 patients had 2 days of collection and 1 had a third.ResponseThe ORR was 14/14 (100%). 10 (71%) had a complete response (CR) / very good partial response (VGPR): 1 (7%) MRD-negative CR by flow, 1 stringent CR, 2 (14%) CR / near CR, 6 (43%) VGPR. 4 (29%) had partial response (PR). 3 of the 6 patients with VGPR and all 4 patients with PR are still on induction therapy and anticipated to have deeper responses. 3 of 4 patients with ISS stage III disease had CR with one being MRD-negative by flow. By time of SCH (after 4 cycles), 1/11 (9%) had attained CR, 7 (64%) VGPR and 3 (27%) PR. To date, 4 patients underwent SCT, and all have attained CR with 1 being MRD-negative by flow. Amongst other patients who underwent SCH, 3 were deemed ineligible for SCT, 1 declined, and 4 are eligible. Median time to best response was 3 months (range 1-11) amongst patients whose response has plateaued, and median time to CR was 4 months (range 1-11). Median follow-up was 8.8 months (range 2-37.3). To date, only 1 patient has progressed, at 18 months after start of therapy, and median PFS has not been reached. No patients have died.ConclusionsCurrent preliminary evidence suggests that CBD is a potent induction regimen. CBD does not appear to impact stem cell collection, and toxicities were acceptable, although increased attention to thromboembolic events is warranted. Further evaluation of this regimen at our maximum dose level is planned. [Display omitted] DisclosuresLentzsch:Caelum Biosciences: Other: leadership position and stock; BMS: Consultancy; Amgen: Consultancy.

Carfilzomib, Elotuzumab and Dexamethasone for Relapsed or Refractory Myeloma Patients

Carfilzomib, Elotuzumab and Dexamethasone for Relapsed or Refractory Myeloma Patients

Ternary Polypeptide Nanoparticles with Improved Encapsulation, Sustained Release, and Enhanced In Vitro Efficacy of Carfilzomib.

To develop a new nanoparticle formulation for a proteasome inhibitor Carfilzomib (CFZ) to improve its stability and efficacy for future in vivo applications. CFZ-loaded ternary polypeptide nanoparticles (CFZ/tPNPs) were prepared by using heptakis(6-amino-6-deoxy)-β-cyclodextrin(hepta-hydrochloride) (HaβCD) and azido-poly(ethylene glycol)-block-poly(L-glutamic acid sodium salt) (N3-PEG-PLE). The process involved ternary (hydrophobic/ionic/supramolecular) interactions in three steps: 1) CFZ was entrapped in the cavity of HaβCD by hydrophobic interaction, 2) the drug-cyclodextrin inclusion complexes were mixed with N3-PEG-PLE to form polyion complex nanoparticles, and 3) the nanoparticles were modified with fluorescent dyes (AFDye 647) for imaging and/or epithelial cell adhesion molecule (EpCAM) antibodies for cancer cell targeting. CFZ/tPNPs were characterized for particle size, surface charge, drug release, stability, intracellular uptake, proteasome inhibition, and in vitro cytotoxicity. tPNPs maintained an average particle size of 50nm after CFZ entrapment, EpCAM conjugation, and freeze drying. tPNPs achieved high aqueous solubility of CFZ (>1mg/mL), sustained drug release (t1/2 = 6.46h), and EpCAM-mediated cell targeting, which resulted in increased intracellular drug accumulation, prolonged proteasome inhibition, and enhanced cytotoxicity of CFZ in drug-resistant DLD-1 colorectal cancer cells. tPNPs improved stability and efficacy of CFZ in vitro, and these results potentiate effective cancer treatment using CFZ/tPNPs in future vivo studies.

Abstract 6329: Carfilzomib: A potential drug against cisplatin-resistant lung adenocarcinoma

Abstract Recent advances in the treatment of lung cancer, such as small molecule inhibitors and immunotherapy, have transformed care. However, platinum-based chemotherapy, such as cisplatin, is the recommended treatment option for those that do not express markers that respond to targeted therapy. In most cases, prolonged exposure to cisplatin eventually renders cancer cells resistant to therapy and patients progress on this line of care. Our study has shown that integrin beta 4 (ITGB4) and paxillin (PXN) in the focal adhesion complex are highly expressed in lung adenocarcinoma (LUAD) and their interaction plays an important role in mediating cisplatin resistance. Disrupting this axis with an FDA-approved compound can potentially alleviate cisplatin resistance in non-small cell lung cancer. Upon screening 10 LUAD cell lines, we determined one KRAS mutant (H2009) and one KRAS wild-type cell line (H1993) with highest resistance to cisplatin using a cell viability assay. Proximity ligation assay and co-immunoprecipitation results confirmed interaction between ITGB4 and PXN in H2009 cells. By virtually screening a library of 1440 FDA-approved compounds that bind to the N-terminal region of PXN, the top 40 hits were screened using a cell-based assay with H358 cells. These results determined the top 11 compounds with the lowest IC50 values (0.8 nM to 1.54 μM). Drug sensitivity to these 11 compounds was tested again using the cisplatin-resistant cell line H2009. Carfilzomib, a proteasome inhibitor, was identified to be the most effective (IC50 = 193.4 nM). This compound was further tested in 3D cell line-derived spheroids and patient cancer tissue-derived organoids that were allowed to form in multi-well ultra-low attachment plates. These cultures were monitored in real-time using the IncuCyte S3 Live-Cell Analysis System. In cisplatin-resistant cell lines H2009 and H1993, carfilzomib was the most effective (IC50 = 193.4 nM, 1.77 μM, respectively), irrespective of KRAS status. Wound healing was impeded by 20% in H2009 with a submicromolar dose (200 nM). In both H2009 and H1993 cells, a sublethal dose of carfilzomib decreased expression of ITGB4 and phospho-Rb (S807/811) and increased expression of p27, γH2AX, and cleaved PARP, indicating cell cycle inhibition and cell death. In H2009 spheroids, carfilzomib (600 nM) was highly effective in decreasing spheroid viability by 60% and inducing a 2.5-fold increase in caspase-3/7-mediated apoptosis. Also in patient-derived organoids, carfilzomib induced an increase in apoptosis by 5-fold in one case and 50-fold in a second case compared to cisplatin. Another proteasome inhibitor ixazomib was among the top 11 compounds tested in H2009 cells but had a higher IC50 (2.93 μM) compared to carfilzomib, indicating greater efficacy of carfilzomib against cisplatin-resistant LUAD. These results impart a potential therapeutic approach for overcoming chemoresistance in LUAD by targeting the focal adhesion complex through repurposing carfilzomib, an FDA-approved compound. Citation Format: Arin Nam, Atish Mohanty, Supriyo Bhattacharya, Saumya Srivastava, Rajendra Pangeni, Dan Raz, John Orban, Prakash Kulkarni, Ravi Salgia. Carfilzomib: A potential drug against cisplatin-resistant lung adenocarcinoma [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 6329.

Abstract LB-269: IDH2 inhibition enhances proteasome inhibitor responsiveness in hematological malignancies

Abstract The introduction of proteasome inhibitors (PIs) into the clinic has transformed the treatment of patients affected by multiple myeloma (MM) and mantle-cell lymphoma (MCL) establishing new standards of care. Despite these improvements, patients continuously relapse or are intrinsically resistant to PIs. Here, to identify druggable targets that synergize with PIs, we carried out a functional screening in MM cell lines using a short hairpin RNA library targeting 152 cancer driver genes, highly representative of all signaling pathways. The Isocitrate Dehydrogenase 2 (IDH2) gene was identified as a top candidate, showing a synthetic lethal activity with the PI Carfilzomib (CFZ). IDH2 is a NADP(+) dependent mitochondrial enzyme which catalyzes the oxidative decarboxylation of isocitrate to 2-oxoglutarate in the tricarboxylic acid (TCA) cycle. We demonstrated that combinations of the pharmacological IDH2 inhibitor AGI-6780 with FDA approved PIs significantly increased apoptotic cell death in ten MM cell lines, both sensitive and resistant to PIs. Combined treatments triggered synergistic cytotoxicity also in four MCL and in two Burkitt's lymphoma cell lines. Importantly, CFZ/AGI-6780 treatment increased death of primary CD138-positive cells from nine MM patients and exhibited a favorable cytotoxicity profile towards peripheral blood mononucleated cells and bone marrow-derived stromal cells. Mechanistically, CFZ/AGI-6780 combination significantly decreased TCA cycle activity and ATP levels, as a consequence of enhanced IDH2 enzymatic inhibition. In contrast, only a slight increase of mitochondrial reactive oxygen species (ROS) was observed. CFZ treatment reduced the expression of nicotinamide phosphoribosyltransferase (NAMPT), a rate-limiting enzyme required for IDH2 activation through the NAD(+)-dependent deacetylase SIRT3. Consistently, combination of CFZ with either NAMPT (FK866) or SIRT3 (AGK7) inhibitors impaired IDH2 activity and increased MM cell death, thus phenocopying CFZ/AGI-6780 effects and putting the proteasome in a direct link with IDH2 inhibition. Finally, inducible IDH2 knock-down enhanced the therapeutic efficacy of CFZ in a subcutaneous xenograft model of MM, resulting in inhibition of tumor progression and extended survival. In conclusion, our data demonstrate that IDH2 inhibition increases the therapeutic efficacy of PIs, thus providing compelling evidence for treatments with lower and less toxic doses, and broadening the application of PIs to other malignancies. Citation Format: Elisa Bergaggio, Chiara Riganti, Giulia Garaffo, Elisabetta Mereu, Nicoletta Vitale, Cecilia Bandini, Elisa Pellegrino, Paola Omedè, Katia Todoerti, Valentina Audrito, Antonio Rossi, Francesco Bertoni, Silvia Deaglio, Antonino Neri, Antonio Palumbo, Roberto Piva. IDH2 inhibition enhances proteasome inhibitor responsiveness in hematological malignancies [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr LB-269.

Phase 2 study of carfilzomib for the treatment of patients with advanced neuroendocrine cancers.

382 Background: Carfilzomib (CFZ) is an irreversible proteasome inhibitor (PI) that exhibits anti-proliferative and pro-apoptotic activity in solid and hematologic tumor cells i n vitro, and is US FDA approved for multiple myeloma. Proteasomes degrade cell cycle inhibitor proteins and inhibition of these proteins offers a novel therapy for the treatment of patients with neuroendocrine tumors (NET). This phase 2 study evaluated the efficacy of CFZ for patients with advance NETs. Methods: Pts with biopsy-proven, advanced, well-to-moderately differentiated NETs, including typical carcinoid and pancreatic islet cell tumors, were treated with CFZ 20 mg/m2 IV Days (D) 1 and 2, then 56 mg/m2 IV D 8, 9, 15, and 16 of Cycle (C) 1, followed by CZF 56 mg/m2 IV D 1, 2, 8, 9, 15, and 16 of C 2 and beyond. Pts continued study treatment (tx) until intolerable toxicity, disease progression, or withdrawal of consent. Restaging occurred every 3 cycles. The primary endpoint was overall response rate (ORR); secondary endpoints were disease control rate (DCR), progression free survival (PFS), and toxicity. Results: 62 pts were enrolled: median age 63 yrs, 61% female, 50% ECOG 0/50% ECOG 1. 65% of pts had carcinoid tumors and 35% of pts had pancreatic NET. The most common primary sites of disease were the pancreas (34%) and the small intestines (21%). 74% of pts had prior systemic therapy, 42% had prior surgery and 16% had prior radiotherapy. Median tx duration was 11 wks. At the time of data cutoff, 31% of pts remained on tx. 32% of pts discontinued due to progressive disease, 16% due AE, and 21% due to pt or physician decision. Two pts (3%) had a confirmed partial response (PR) and 1 pt (2%) had an unconfirmed PR; 4 ongoing patients have not yet been evaluated for response. The ORR was 3.23% (95% CI 0.4%, 11.2%), the DCR was 53.23% (CI 95% 40.1%, 66.0%), and median PFS was 8.1 months. The most frequently reported tx-related AEs were nausea (52%; Grade 3/4 [G3/4], 2%), fatigue (42%; G3/4, 3%), vomiting (36%; G3/4, 2%), and diarrhea (27%; G3/4, 5%). Conclusions: CFZ tx was well-tolerated in this pt population. Future plans will be determined once response data are available on all patients. Updated results will be presented. Clinical trial information: NCT02318784.

Safety and Efficacy of Carfilzomib (CFZ) in Previously-Treated Systemic Light-Chain (AL) Amyloidosis

Safety and Efficacy of Carfilzomib (CFZ) in Previously-Treated Systemic Light-Chain (AL) Amyloidosis

Safety and efficacy of carfilzomib (CFZ) in previously-treated systemic light-chain (AL) amyloidosis

Safety and efficacy of carfilzomib (CFZ) in previously-treated systemic light-chain (AL) amyloidosis

Abstract 1737: Carfilzomib transcriptionally regulates CIP2A/PP2A/p-Akt signaling and induces apoptosis in leukemia cells

Abstract Background: Protein phosphatase 2A (PP2A) has been shown to be an important tumor suppressor protein and loss of PP2A function has been identified in several solid cancers and in leukemias. Recent studies have suggested strategies for enhancing PP2A activity as an anti-leukemic approach. Among the potential key players regulating PP2A, a new oncoprotein, called cancerous inhibitor of protein phosphatase 2A (CIP2A), is recently identified as a key factor in the development of malignancies in various human cells. Previously we studied novel drug mechanisms of bortezomib, a proteasome inhibitor, on acute leukemia cells. We discovered that CIP2A plays an indispensable role in mediating bortezomib-induced apoptosis in acute leukemia cells (Hematologica 2013), hepatocellular carcinoma cells (Oncogene 2010) and in breast cancer cells (Breast Cancer Research 2012). Importantly, this mechanism by bortezomib is independent to its proteasome inhibition. Carfilzomib, a more selective proteasome inhibitor than bortezomib, has shown efficacy in multiple myeloma and is being investigated in phase III clinical trials. In this study, we examined the effect of carfilzomib on CIP2A in leukemia cells. Methods: Leukemia cell lines (HL-60, KG-1, THP-1, and K562) were used for in vitro studies. Apoptosis was examined by both flow cytometry and Western blot. Signal transduction pathways in cells were assessed by Western Blot. Quantitative RT-PCR was used for assessing gene transcription. In vivo efficacy of carfilzomib was tested in nude mice with subcutaneous leukemia xenografts. Results: We found carfilzomib induced differential antiproliferative effects and apoptosis. HL-60, KG-1 and THP-1, but not K562 cells, were sensitive to carfilzomib-induced apoptosis. Similarly, carfilzomib-induced apoptosis may be dissociated with its proteasome inhibition. We found CIP2A mediated this apoptotic effect of carfilzomib in leukemia cells. Carfilzomib down-regulated CIP2A in association with p-Akt downregulation. Furthermore, carfilzomib increased PP2A activity and over-expression of CIP2A up-regulated p-Akt and suppressed carfilzomib-induced apoptosis. In addition, carfilzomib downregulated CIP2A mRNA but did not affect the degradation of CIP2A protein. Further dissecting the regulatory mechanism showed that carfilzomib may affect CIP2A transcription though transcriptional factors. Importantly, carfilzomib demonstrated anti-tumor activity in xenografted mice models. Conclusions: CIP2A is a major determinant mediating carfilzomib-induced apoptosis in leukemia cells and may be a therapeutic target in leukemia. This study disclosed a novel drug mechanism of carfilzomib in leukemia cells. (Supported by Taiwan Clinical Oncology Research Foundation, MOST 103-2325-B-075-002, V103C-141; and TVGH-NTUH Joint Research Program VN103-08) Citation Format: Chun-Yu Liu, Wen-Chun Tsai, Man-Hsin Hung, Yuan-Bin Yu, Po-Shen Ko, Cheng-Hwai Tzeng, Chung-Wai Shiau, Kuen-Feng Chen. Carfilzomib transcriptionally regulates CIP2A/PP2A/p-Akt signaling and induces apoptosis in leukemia cells. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1737. doi:10.1158/1538-7445.AM2015-1737

Abstract 1735: Identification of novel synthetic lethal interactions in small cell lung cancer with the proteasome inhibitor carfilzomib

Abstract Proteasome inhibition (PI) has emerged as a valuable cancer treatment in hematological malignancies by causing a disruption of protein homeostasis. While proteasome inhibitors have been historically unsuccessful in the clinic for solid tumors, all cancer cell lines succumb to proteasome inhibition in vitro. Solid tumor cell lines have a higher threshold for disruption of protein homeostasis; as they require continuous exposure to achieve cytotoxicity similar to pulsatile exposure of PI in heme cell lines. The in-vivo half-life of proteasome inhibitors is short (∼1hr) making it challenging to mimic in vitro continuous treatment. Therefore we explored the option of sensitizing solid tumors to proteasome inhibitors through combination therapy. In order to identify novel synthetic lethal interactions with PI, we performed a screen utilizing a pooled siRNA library targeting 2240 genes of the druggable genome in combination with the proteasome inhibitor carfilzomib (CFZ) or DMSO. Cells were first transfected with the siRNA for 24 hours and then treated with CFZ or DMSO for an additional 72h to assess synergy. We performed the screen in small cell lung cancer (SCLC), an unmet medical need. Preliminary responses in SCLC patients were observed with CFZ in an all comers solid tumor trial (Papadopoulos, et al. Cancer Chemother Pharmacol, 2013). The screen was performed in NCI-H841 cells that are adherent, easy to culture, and have high transfection efficiency. The combined effect of siRNA and CFZ on viability was measured using a Sensitivity Index (SI), which ranges from -1 (antagonistic) to 1 (synergistic). Using an SI threshold >0.2, we identified 33 synthetic lethal genes when H841 cells were treated with an IC9 of CFZ. To validate screen hits, we performed experiments using single siRNA reagents (4 - 6 sequences per gene) in combination with CFZ in NCI-H841. Two hits were confirmed with two or more single siRNAs sensitizing cells to CFZ. These genes (TGFBR3 and GRK6) are of particular interest because of their involvement in proliferation signaling mechanisms. Subsequent screens have also uncovered two additional genes, involved in the protein degradation and trafficking pathway (CLPP and COG8), which meet the same validation criteria for synergy. The characterization of these hits is currently on-going in a panel of SCLC lines, and in cells engineered with CRISPR technology to achieve a near complete knockout. In parallel, we are testing commercially available reagents targeting our proteins of interest to validate our results. Preliminary data with a published GRK6 inhibitor, GF109203x, demonstrates synergy with Bliss scores of 0.35 in H841 and 0.44 in DMS114 SCLC lines (Zhou et al. J Pharmacol Exp Ther, 2001). In summary, we have identified druggable targets that would potentiate CFZ efficacy towards solid tumors and may elucidate the PI mechanism of action. Citation Format: Vincent B. Masto, Alana G. Lerner, Shirin Arastu-Kapur. Identification of novel synthetic lethal interactions in small cell lung cancer with the proteasome inhibitor carfilzomib. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1735. doi:10.1158/1538-7445.AM2015-1735

Carfilzomib, cyclophosphamide, and dexamethasone in patients with newly diagnosed multiple myeloma: a multicenter, phase 2 study

AbstractThis multicenter, open-label phase 2 trial determined the safety and efficacy of carfilzomib, a novel and irreversible proteasome inhibitor, in combination with cyclophosphamide and dexamethasone (CCyd) in patients with newly diagnosed multiple myeloma (NDMM) ≥65 years of age or who were ineligible for autologous stem cell transplantation. Patients (N = 58) received CCyd for up to 9 28-day cycles, followed by maintenance with carfilzomib until progression or intolerance. After a median of 9 CCyd induction cycles (range 1-9), 95% of patients achieved at least a partial response, 71% achieved at least a very good partial response, 49% achieved at least a near complete response, and 20% achieved stringent complete response. After a median follow-up of 18 months, the 2-year progression-free survival and overall survival rates were 76% and 87%, respectively. The most frequent grade 3 to 5 toxicities were neutropenia (20%), anemia (11%), and cardiopulmonary adverse events (7%). Peripheral neuropathy was limited to grades 1 and 2 (9%). Fourteen percent of patients discontinued treatment because of adverse events, and 21% of patients required carfilzomib dose reductions. In summary, results showed high complete response rates and a good safety profile. This trial was registered at clinicaltrials.gov as #NCT01346787.

Selective Inhibitor Of Nuclear Exports (SINE) KPT-330 In Combination With The Novel Proteasome Inhibitor Carfilzomib As a Novel Therapeutic Regimen For Treating Aggressive B-Cell Lymphomas

Aggressive non-Hodgkin lymphomas (NHL), such as Diffuse Large B cell lymphoma (DLBCL) and mantle cell lymphoma (MCL), are one of a small number of important human cancers increasing in incidence in the US over the last four decades. Although these lymphomas are now potentially curable, almost half the treated patients still develop relapsed/refractory disease with poor survival outcomes, indicating an urgent need for better therapeutic approaches with improved efficacy. Double–hit lymphomas (DHL) constitute a particularly aggressive subtype of DLBCL and are characterized by a chromosomal breakpoint affecting the MYC/8q24 locus in combination with another recurrent breakpoint, usually a t(14;18)(q32;q21) involving BCL2. Prognosis for DHL is extremely poor, indicating a need for new treatment options as well. Multi-drug combination therapies are expected to potentiate therapeutic responses and delay disease recurrence by blocking adaptive resistance responses. Carfilzomib (CFZ), a novel second-generation proteasome inhibitor, and the novel Selective Inhibitor of Nuclear Exports (SINE) KPT-330 are effective treatments for refractory lymphomas. We hypothesized that combining the two would be even more successful because the drugs target different cellular pathways and processes in malignant B-cells. CFZ inhibits chymotrypsin-like, protein-degrading activity in the ubiquitin-proteasome pathway while KPT-330 irreversibly inhibits the major nuclear export receptor, chromosome region maintenance 1, CRM1, also termed XPO1. This study investigates whether the effects of CFZ and KPT-330 in combination are synergistic and thus more effective, reducing side effects and chemoresistance. Two DLBCL cell lines, DOHH-2 and OCI-Ly10, two DH-DLBCL cell lines, CJ and U-2973, and two MCL cell lines, Mino and Jeko-1, were used. Working with these cell lines, we identified and analyzed the increase in the efficacy of the combination over single agents alone through MTS proliferation and Annexin-V binding apoptosis assays. Growth inhibitory combination indexes for each cell line were calculated, and the Chou-Talalay Method was used to quantify additive effects (CI=1), synergistic effects (CI<1), or antagonistic affects (CI>1). Results indicated strong synergistic behavior of the combinatorial therapy, with many of the dose combinations indexes falling below 1. Apoptosis assays also showed a high degree of synergy when combining CFZ with KPT-330. The efficacy of CFZ and KPT-330 in combination signifies the combination's potential as a foundation for future studies, treatments, and clinical trials. Disclosures:Kirk:Onyx Pharmaceuticals: Employment, Equity Ownership. Kauffman:Karyopharm Therapeutics Inc.: Employment. Shacham:Karyopharm : Employment, Equity Ownership, Membership on an entity's Board of Directors or advisory committees, Patents & Royalties.

Results of a phase I/II study (NCT01365559) of carfilzomib (CFZ) replacing bortezomib (BTZ) in BTZ-containing regimens for BTZ-treated patients (pts) with relapsed and refractory multiple myeloma (MM).

8599 Background: Recent data has shown that single-agent CFZ can produce responses among MM pts refractory to previous treatment regimens including those containing BTZ. We conducted an intrapatient phase I/II trial investigating the safety and efficacy of CFZ as a replacement for BTZ in BTZEcontaining regimens to which pts have progressed. Methods: Eligible pts progressed while receiving their most recent BTZEcontaining regimen after at least 4 doses of BTZ at ≥1.0 mg/m² in ≤4 weeks per cycle. CFZ replaced BTZ in each regimen via intravenous administration over 30 min on days 1, 2, 8, 9, 15, and 16 of each cycle. Treatment continued using the same dose(s) and schedule(s) of each drug administered in the BTZEcontaining regimen. CFZ doses were escalated on each of the first 4 cycles from 20 to 27, 36, and 45 mg/m² or until a maximum tolerated dose (MTD) was reached for that regimen. Results: Of 37 enrolled pts, 33 were evaluable for efficacy and 37 for safety. Pts received a median of 4 prior treatments (range, 1-23) and 2 different BTZ-containing regimens (range, 1-13). Pts were treated with CFZ and a variety of different combinations of agents, including: bendamustine, clarithromycin, cyclophosphamide, dexamethasone, melphalan, methylprednisolone, pegylated liposomal doxorubicin, thalidomide, lenalidomide, and ascorbic acid. Pts have completed a median of 3 cycles with 12 pts going on to maintenance. One of 14 combinations, CFZ + ascorbic acid + cyclophosphamide, has reached a MTD at 45 mg/m2. Clinical benefit was seen in 23 (70%) evaluable pts (complete response = 6%; very good partial response = 18%; partial response = 21%; minor response = 24%) with another 18% showing stable disease. The median time to progression is 8.8 mo. (95% CI: 6.4-11.1 mo.) with 21 pts progressing overall and 9 progressing on study treatment. The most common ≥ G3 adverse events were lymphopenia (35% of pts), thrombocytopenia (19%), neutropenia (11%), and anemia (8%). Conclusions: These results suggest that replacement of BTZ with CFZ in a BTZ-containing combination regimen to which a MM patient is failing often leads to responses and is well-tolerated. Clinical trial information: NCT01365559.

Carfilzomib in multiple myeloma patients with renal impairment: pharmacokinetics and safety

This phase 2 study assessed the safety, pharmacokinetics, pharmacodynamics and efficacy of carfilzomib, a selective proteasome inhibitor, in patients with multiple myeloma and varying degrees of renal impairment, including patients on chronic hemodialysis. Patients were grouped by creatinine clearance: >80 ml/min, 50–80 ml/min, 30–49 ml/min, <30 ml/min and chronic hemodialysis. Carfilzomib was administered on days 1, 2, 8, 9, 15 and 16 in 28-day cycles: 15 mg/m2 (Cycle 1), 20 mg/m2 (Cycle 2) and 27 mg/m2 (Cycles 3+). There were no differences in carfilzomib clearance or exposure among patients with normal renal function and any group with renal impairment. Grade 3/4 adverse events (AEs) included anemia (28.0%), thrombocytopenia (20.0%), lymphopenia (18.0%) and fatigue (14.0%). AEs were similar among groups. At 15 mg/m2, proteasome inhibition up to 85% was observed and did not differ among groups. Although nearly 50% of patients were refractory to both bortezomib and lenalidomide, end of study partial response or better (overall response rate) was 25.5% with 7.9 months median duration of response. In conclusion, the pharmacokinetics and safety of carfilzomib were not influenced by the degree of baseline renal impairment, including in patients on dialysis, and carfilzomib was well tolerated and demonstrated promising efficacy.

Carfilzomib: A new proteasome inhibitor for relapsed or refractory multiple myeloma

The pharmacology, pharmacokinetics, clinical trials, adverse effects, dosage recommendations, and economic considerations of carfilzomib are reviewed. Multiple myeloma accounts for approximately 10-15% of all hematologic malignancies and 20% of blood-related cancer deaths. Despite recent advances in the treatment of multiple myeloma, most patients will eventually relapse, requiring further treatment. Carfilzomib is a new proteasome inhibitor that primarily targets the chymotrypsin-like activity of the 20S proteasome. The safety and efficacy of carfilzomib was demonstrated in the PX-171-003-A1 trial, a prospective phase II trial in patients with relapsed or refractory multiple myeloma who had received at least 2 prior therapies including a proteasome inhibitor and an immunomodulatory agent. Common adverse effects included fatigue (55.5%), anemia (46.8%), nausea (44.9%), and thrombocytopenia (36.3%). The recommended dose of carfilzomib for the first cycle is 20 mg/m(2) on 2 consecutive days each week for 3 weeks in a 4-week cycle escalating to 27 mg/m(2) for subsequent cycles. It is recommended that patients receive premedication with dexamethasone during cycle 1 and cycle 2 to minimize risk of infusion reactions. Carfilzomib provides a clinical benefit to patients with relapsed or refractory multiple myeloma who have been previously treated with a proteasome inhibitor and an immunomodulatory agent.

Relapsed and refractory lymphoid neoplasms and multiple myeloma with a focus on carfilzomib

Proteasomal inhibition revolutionized myeloma therapies in this decade of novel agents. The only US Food and Drug Administration approved proteasome inhibitor so far, bortezomib effectively targets the constitutive proteasome subunit β5 of the 26S proteasome. Bortezomib induces high and quality response rates that are durable. However, myeloma cells acquire resistance to bortezomib through various mechanisms. Further, grade 3/4 peripheral neuropathy is seen in up to a quarter of patients treated with bortezomib. While the recent change in the mode of administration via the subcutaneous route is associated with a lower incidence of grade 3/4 peripheral neuropathy, it remains a major concern. The second generation proteasome inhibitors are promising, with increased preclinical efficacy and a better administration schedule. The current review spotlights the second generation proteasome inhibitors with special focus on the safety and efficacy of carfilzomib, an epoxyketone with lesser peripheral neuropathy, which exhibits irreversible proteasome inhibition. In this article, we review the pharmacology and preclinical and clinical efficacy and safety of carfilzomib alone and in combination with other chemotherapeutic agents in the various lymphoid neoplasms and multiple myeloma as well as ongoing clinical trials.

A Phase 1/2 Study of Carfilzomib As a Replacement for Bortezomib for Multiple Myeloma (MM) Patients (pts) Refractory to a Bortezomib-Containing Combination Regimen

AbstractAbstract 4063 Background:Carfilzomib has shown promise in treating both newly diagnosed and relapsed/refractory MM patients. Recent data has suggested that single agent carfilzomib can produce a response for MM pts refractory to previous treatment regimens, including prior bortezomib-containing regimens. We conducted an intrapatient Phase 1/2 trial investigating the safety and efficacy of carfilzomib as a replacement for bortezomib in bortezomib-containing regimens to which pts have progressed. Methods:Eligible pts had to have progressed while receiving their most recent bortezomib-containing regimen after at least 4 doses of bortezomib at ≥ 1.0 mg/m2 in ≤ 4 weeks per cycle. Patients treated with bortezomib-containing combination regimens, including alkylating agents, anthracyclines, glucocorticosteroids, and/or immunomodulatory agents were eligible. Carfilzomib replaced bortezomib in each regimen via intravenous administration over 30 min on days 1, 2, 8, 9, 15, and 16 of each 28 day cycle. For each pt, carfilzomib doses were escalated on each of the first 4 cycles from 20 to 27, 36, and 45 mg/m2 or until maximum tolerated dose (MTD) was reached for that regimen. Aside from carfilzomib replacing bortezomib, regimens utilized the same dose(s) and schedule(s) of each drug administered in the most recent bortezomib-containing regimen to which the patient was refractory. Results:The trial has currently enrolled 32 of 45 planned patients. Pts received a median of 6 prior treatments (range, 1–18) and 2 different bortezomib-containing regimens (range, 1–13). Pts were treated with carfilzomib and 13 different combination regimens at varying doses and schedules. Agents in these combination regimens varied per patient, potentially including any of the following: ascorbic acid, bendamustine, clarithromycin, cyclophosphamide, dexamethasone, lenalidomide, melphalan, methylprednisolone, pegylated liposomal doxorubicin, and/or thalidomide. Six patients received a regimen containing IMiDs (thalidomide or lenalidomide). Pts have completed a median of 3 cycles (range: 0–12) with a median of 5.9 months of follow up (range: 0.4–14.1). To date, 1 regimen, carfilzomib + ascorbic acid + cyclophosphamide, has reached MTD with the maximum dose of carfilzomib (45 mg/m2) without any DLTs.Efficacy data stems from 24 of 32 enrolled pts who have completed at least 1 cycle of treatment. Clinical benefit was seen in 18 (75%) pts (complete response = 8.3%; very good partial response = 16.7%; partial response = 29.2%; minor response = 20.8%) with another 16.7% showing stable disease. Notably, response was achieved for each type of agent included in the trial across a variety of specific treatment combinations. Only 3 pts have progressed while on study, one with progressive disease after an initial response. Kaplan-Meier analysis reveals the median progression-free survival (PFS) at this point in the study to be 10 months (95% confidence interval: 8.6–11.2). The median time to progression (TTP) and duration of response (DOR) have not yet been reached.Safety data stems from all 32 enrolled pts. The most common grade 3/4 hematologic adverse events include: thrombocytopenia, occurring in 16 pts (G3: 5; G4: 2); lymphopenia occurring in 12 pts (G3: 6; G4: 1) and fever occurring in 2 pts (G3). The most common grade 3/4 non-hematologic adverse events include: fever, occurring in 8 pts (G3: 2); urinary tract infection, occurring in 3 pts (G3: 1); sepsis occurring in 1 pt (G4); pneumonia occurring in 2 pts (G3: 1); tumor lysis syndrome occurring in 1 pt (G3). Ten pts experienced a serious adverse event on study. Conclusions:These early results suggest that carfilzomib is an effective and tolerable replacement for bortezomib among pts who are refractory to bortezomib-containing combination regimens. These results appear to be applicable to a variety of combination regimens consisting of a wide array of therapeutic agents. Disclosures:Berenson:Onyx: Consultancy, Honoraria, Research Funding, Speakers Bureau.