ALBERT

Description: Background: Increasingly thalidomide (Thal) plus dexamethasone (Dex) is being used as initial therapy for multiple myeloma (MM), but there is a need to minimize non-hematologic toxicity with this regimen. CC-5013 (lenalidomide; Revlimid™) is a more potent analog of thalidomide with significantly fewer non-hematologic toxicities that has shown promising results in relapsed refractory myeloma. We report the initial results of the first phase II trial using the combination of CC-5013 plus Dex (Rev/Dex) as initial therapy for newly diagnosed MM. Methods: The trial is designed to accrue 31 eligible patients; 13 patients (pts) (11 male and 2 female) were analyzed in this interim report. Patients were enrolled between February 2004 and July 2004. CC-5013 was given orally at a dose of 25 mg daily on days 1–21 of a 28-day cycle. Dex was given orally at a dose of 40 mg daily on days 1–4, 9–12, 17–20 of each cycle. Patients also received an aspirin once daily as thrombosis prophylaxis. Response was defined as a decrease in serum monoclonal (M) protein by 50% or higher and a decrease in urine M protein by at least 90% or to a level less than 200 mg/24 hours. Responses were assessed on an intent to treat basis. Results: The median age was 61 years (range, 32–78). 8 patients (62%) had Stage III myeloma. 11 of the 13 patients achieved an objective response yielding a response rate of 85% within 1–2 months of therapy. So far 6 patients have experienced grade 3 adverse events. These include one episode each of CD4-count 〈 200/mm3, anemia, neutropenia, increased liver enzymes, muscle weakness, agitation, hyperglycemia, cardiac arrhythmia, pneumonitis, and colonic perforation (underlying diverticulitis and dexamethasone suspected). No deep vein thrombosis or grade 4 or higher adverse events have been observed so far. Conclusions: Rev/Dex appears active and well tolerated in the treatment of newly diagnosed MM and is a potential alternative to Thal/Dex. However, these results are preliminary and responses are still being evaluated and need to be confirmed in the final analysis of this trial. A large randomized trial using Rev/Dex as initial therapy for MM is expected to be activated by the Eastern Cooperative Oncology Group later this year.

Description: Background: Though STI-571 (Gleevec™) was designed to specifically inhibit the bcr-abl gene product, it inhibits other receptor tyrosine kinases at physiologically attainable concentrations, including c-kit (steel factor receptor, stem cell factor receptor, SCF-R or CD 117). Studies have shown that about one-third of patients with multiple myeloma or monoclonal gammopathy of undetermined significance have plasma cells that display reactivity for c-kit. Others have shown that several myeloma cell lines and fresh myeloma bone marrow cells proliferate in response to stem cell factor. mRNA transcripts for c-kit ligand and, more commonly, its receptor have been detected in myeloma cell lines RPMI 8226, JJN3, U266 B1, NCI-H929, ARH77 and HS-Sultan by RT-PCR. Methods: Patients were eligible for study if they presented with relapsed or refractory myeloma, an ECOG performance score 〈 3, ability to sign informed consent, serum creatinine

Description: Purpose: Flavopiridol is a cyclin-dependent kinase inhibitor with preclinical activity against multiple myeloma cells in vitro and ex vivo. It can induce apoptosis in non-cycling human cell lines, including RPMI-8226, a myeloma cell line. Suggested mechanisms of cytotoxicity include down regulation of anti-apoptotic regulators, direct binding to duplex DNA, disruption of transcription factor/DNA binding, upregulation of p53, inhibition of transcription, and inhibition of angiogenesis. A Phase II multicenter trial was conducted to determine the activity of flavopiridol in patients with relapsed or refractory multiple myeloma. Experimental Design: Eighteen patients were treated with 1 hour flavopiridol infusions (50 mg/m(2)/day) for 3 consecutive days every 21 days. Responses were assessed according to IBMTR criteria each cycle. Serial bone marrow aspirates were collected before and immediately after flavopiridol treatment to measure in vivo and ex vivo effects of flavopiridol on patient plasma cells. Immunoblotting for Mcl-1, Bcl-2, p53, cyclin D, phosphoRNA polymerase II and phosphoSTAT 3 was conducted on total cellular proteins isolated from sorted plasma/myeloma cells. Ex vivo assessment of flavopiridol sensitivity of freshly collected myeloma cells was performed for 5 patients pre-therapy. Results: Median age of patients ranged from 49 to 81 years, with a median of 65 years. Patients had received a median of 3 (range, 1–5) treatment regimens prior to enrollment. Sixty-one percent of patients were refractory to prior therapy and fifty-five percent had received prior high dose therapy with hematopoietic stem cell support. The immunoglobulin isotypes of the patients were as follows: IgG (10), IgA (4), light chain (3), and non-secretory (1). At enrollment, 13 patients had a beta-2 microglobulin greater than 3.5. Seven had a plasma cell labeling index greater than or equal to 1%. Four had an elevated LDH. The trial was stopped at time of interim analysis due to a lack of clinical efficacy. Of eighteen treated patients, 15 progressed (including 1 death on study) and 3 discontinued due to toxicity. All patients have ended the active treatment phase, and the mean number of cycles administered for all enrolled patients was 1.6 cycles (range 1–3). No objective responses were observed. The most frequent adverse events were leukopenia and diarrhea (83% each), followed by thrombocytopenia, nausea, and fatigue (61% each). Ex vivo flavopiridol treatment of pre-therapy patient plasma/myeloma cells led to cytotoxicity, but only after longer exposure times at higher flavopiridol concentrations than were anticipated to be achieved in vivo. Further, immunoblotting demonstrated no indication that known in vitro cellular effects of flavopiridol were recapitulated in vivo. Conclusions: Flavopiridol has little single-agent activity in relapsed or refractory multiple myeloma when administered at this dose and schedule, which is likely due to the inability to achieve biologically relevant concentrations in patients. .

Description: RIZ1 (PRDM2) is a tumor suppressor gene on 1p36 that frequently undergoes deletion, rearrangements, and loss of heterozygosity in a broad spectrum of tumors. RIZ1 is a member of the nuclear protein methyltransferase superfamily involved in chromatin remodeling. RIZ1 contains a ~130 amino acid conserved domain (PR or SET) that is important in chromatin-mediated regulation of gene expression and in the development of cancer. RIZ1 methylates Histone H3 on K9 and this activity may play a role in transcription repression as H3-K9 methylation is known to be associated with repression. Aberrant activities or mistargeting of chromatin modifying activities are proving to have unexpected links to cancer. We and others have shown that RIZ1 expression is down regulated in human leukemias and in the human erythroleukemia cell line K562. Expression of RIZ1 in K562 reduced proliferation, increased apoptosis, and promoted erythroid differentiation. To understand how RIZ1’s DNA binding, methyltransferase, and transcription repressor functions are related to its tumor suppressor activity it is necessary to characterize RIZ1 target genes. We used DNA microarrays to globally monitor how RIZ1 affects gene expression profiles. We constructed a K562 cell line with RIZ1 stably integrated under the control of a CMV promoter and analyzed the gene expression profiles of K652 and K562 + RIZ1 using a 42K Stanford human gene microarray. By comparing the gene expression profiles of these cell lines, we identified potential RIZ1 gene targets that are up and down regulated in the presence of RIZ1. In total, we identified 5 upregulated genes and 20 down regulated genes using significance analysis of microarrays (SAM) and standard deviation filter analysis of the gene expression data. RIZ1-mediated changes in gene expression profiling indicate that RIZ1 is potentially involved in the regulation and connection of the IGF-1 (IGF-1, IGFBP2) and integrin (LMS1) pathways, and in the activation of the TGF-β (SPARC) pathway. The genes perturbed by RIZ1 expression suggest that the tumor suppressor properties of RIZ1 arise from its control of proliferation, apoptosis and differentiation using these pathways. Finally, we observed an overrepresentation of the SP-1 transcription factor binding sites in genes that are upregulated in the absence of RIZ1. This correlates with the ability of RIZ1 to recognize SP1 sequences.

Description: Background: Primary systemic amyloidosis (AL) is an incurable plasma cell dyscrasia with limited therapeutic options. Based on the observed 25 to 50% partial response rates in myeloma patients, thalidomide has been tried in patients with AL. Two reports (Dispenzieri et al, Amyloid10:247; 2003; Seldin et al, Clinical Lymphoma3:241; 2003) have demonstrated that standard dose, single agent thalidomide (≥ 200 mg per day) has a higher than expected rate of adverse events in AL patients without hematologic or organ response, potentially due to rapid patient attrition. We therefore performed a prospective clinical trial using low dose, single agent thalidomide in patients with AL. Methods: In August 2001, we began accrual to a phase II trial of low dose thalidomide for patients with AL. Eligibility included: age ≥ 18 years, creatinine 45%, histochemical proof of amyloid and a monoclonal plasma cell dyscrasia, symptomatic organ involvement, and ability to supply informed consent. Patients were started with thalidomide 50 mg per day, with a dose escalation to a maximum dose of 400 mg per day over a 19 week period as tolerated. Patients were evaluated monthly by their physician. These office visits were staggered with telephone toxicity checks monthly by the primary investigator. The endpoint of the study was hematologic and organ response by 12 months. Results: Eighteen patients were treated. The median age was 66 years (range 43–83). Eight were male. Twenty-eight percent had an ECOG performance status of 2 or 3. Five patients (28%) had received no prior therapy. Five had received one prior regimen; 6, two prior; and 2, ≥ three. Three had received prior PBSCT. Sixteen patients had a monoclonal lambda plasma cell disorder; two, monoclonal kappa. Immunoglobulin heavy chains were IgG (n=9), IgM (n=5), IgA (n=1), and none (n=3). Twelve patients (67%) had cardiac involvement; twelve (67%) renal; two liver; two symptomatic gastrointestinal; one pulmonary; and two nerve involvement. Study participants had significant symptomatology at baseline with dyspnea (n=12), light-headedness (n=6), and edema (n=13). Median number of organs involved was 1, range (1 to 4). Median time on study drug was 5.6 months, range 0.7–24 months. Reasons for discontinuation included: progression, 7 (39%); 3 each (17%) for adverse events, death, and patient refusal; and other causes in 2. The median tolerated dose was 100 mg. There were no hematologic responses observed. The overall organ response rate was 11%. There was one renal response at 1 year and a gastrointestinal response at 3 months with 24 hour fecal fat changing from 21 to 8.7 grams. The most common adverse effects attributable to thalidomide were: constipation (78%), edema (44%), sinus bradycardia (17%), dyspnea (11%), and paresthesias (11%). Light-headedness, rising creatinine, thrombosis, infection, syncope, and rash was attributed to the thalidomide in 5.6% of patients. Conclusions: Low dose thalidomide is tolerable in this fragile group of patients, but as a single agent efficacy is limited. Further study of combination therapy of thalidomide and low dose dexamethasone may be warranted. A study using the next generation immune modulatory drug Revlimid is scheduled to open to accrual. Funded by NIH grant CA 91561 and Celgene.

Description: Heterogeneity in the clinical behavior of patients with chronic lymphocytic leukemia (CLL) makes it difficult for physicians to accurately identify which patients may benefit from an early or more aggressive treatment strategy and to provide patients with relevant prognostic information. Given the potential efficacy of newer therapies and the desire to treat patients at “optimum” times, it is more important than ever to develop sensitive stratification parameters to identify patients with poor prognosis. The evolution of risk stratification models has advanced from clinical staging and use of basic laboratory parameters to include relevant biologic and genetic features. This article will review the dramatic progress in prognostication for CLL and will propose statistical modeling techniques to evaluate the utility of these new measures in predictive models to help determine the optimal combination of markers to improve prognostication for individual patients. This discussion will also elaborate which markers and tools should be used in current clinical practice and evaluated in ongoing clinical trials.