Phase II California Cancer Consortium Trial of Gemcitabine-Eribulin Combination in Cisplatin-Ineligible Patients With Metastatic Urothelial Carcinoma: Final Report (NCI-9653).

PURPOSE: Patients with metastatic urothelial carcinoma are often ineligible for cisplatin-based treatments. A National Cancer Institute Cancer Therapy Evaluation Program-sponsored trial assessed the tolerability and efficacy of a gemcitabine-eribulin combination in this population. METHODS: Patients with treatment-naïve advanced or recurrent metastatic urothelial carcinoma of the bladder, ureter, or urethra not amenable to curative surgery and not candidates for cisplatin-based therapy were eligible. Cisplatin ineligibility was defined as creatinine clearance less than 60 mL/min (but ≥ 30 mL/min), grade 2 neuropathy, or grade 2 hearing loss. Treatment was gemcitabine 1,000 mg/m2 intravenously followed by eribulin 1.4 mg/m2, both on days 1 and 8, repeated in 21-day cycles until progression or unacceptable toxicity. A Simon two-stage phase II trial design was used to distinguish between Response Evaluation Criteria in Solid Tumors, version 1.1 objective response rates of 20% versus 50%. RESULTS: Between June 2015 and March 2017, 24 eligible patients with a median age of 73 years (range, 62 to 88 years) underwent therapy. Performance status of 0, 1, or 2 was seen in 11, 11, and two patients, respectively. Sites of disease included: lymph nodes, 16; lungs, nine; liver, seven; bladder, five; bones, two. Median number of cycles received was four (range, one to 16). Of 24 patients, 12 were confirmed responders; the observed objective response rate was 50% (95% CI, 29% to 71%). Median overall survival was 11.9 months (95% CI, 5.6 to 20.4 months), and median progression-free survival was 5.3 months (95% CI, 4.5 to 6.7 months). The most common treatment-related any-grade toxicities were fatigue (83% of patients), neutropenia (79%), anemia (63%), alopecia (50%), elevated AST (50%), and constipation, nausea, and thrombocytopenia (42% each). CONCLUSION: Gemcitabine-eribulin treatment response and survival for cisplatin-ineligible patients compare favorably to other regimens. Additional research is needed.

A dose escalation feasibility study of lenalidomide for treatment of symptomatic, relapsed chronic lymphocytic leukemia.

Adequate dosing of lenalidomide in Chronic Lymphocytic Leukemia (CLL) remains unclear. This study determined maximum tolerated dose (MTD) in relapsed CLL patients (Cohort A) and patients achieving a partial response (PR) or better to recent therapy (Cohort B). Thirty-seven patients were enrolled. MTD was 2.5mg followed by 5.0mg continuous. In Cohort A, tumor flare grade 1-2 occurred in 15 patients (50%) and grade 3 in 1 patient (3%). Cohort A had 19 of 23 evaluable (83%) patients, 4 PR (17%) and 15 (65%) stable disease (SD), Cohort B had 6 of 7 patients (86%) with SD. Despite overall response rate not being high, many patients remained on therapy several months with SD.

Phase I study of GTI-2040, a ribonucleotide reductase antisense, with high dose cytarabine in patients with relapsed/refractory acute myeloid leukemia.

We hypothesized that GTI-2040, a 20-mer oligonucleotide complementary to the R2 subunit mRNA of ribonucleotide reductase, combined with high dose cytarabine (HiDAC) would result in enhanced cytotoxicity by favoring Ara-CTP DNA incorporation. In a phase I dose escalation trial, adults (≥ 60 years) with refractory or relapsed acute myeloid leukemia (AML) received daily HiDAC plus infusional GTI-2040. Using a novel assay, evidence of intracellular drug accumulation and target R2 down-regulation was observed. GTI-2040/HiDAC can be administered safely. However, with no complete remissions observed, alternative doses and schedules may need to be investigated to achieve clinical activity in older patients with AML.

Pharmacokinetics and dose escalation of the heat shock protein inhibitor 17-allyamino-17-demethoxygeldanamycin in combination with bortezomib in relapsed or refractory acute myeloid leukemia.

Abstract This phase I study was conducted to determine the maximum tolerated dose (MTD) and dose limiting toxicities (DLTs) of the heat shock protein 90 (HSP90) inhibitor 17-allyamino-17-demethoxygeldanamycin (17-AAG) in combination with bortezomib, and to provide pharmacokinetic data in relapsed or refractory acute myeloid leukemia (AML). Eleven patients were enrolled. The MTD was 17-AAG 150 mg/m(2) and bortezomib 0.7 mg/m(2). Hepatic toxicity and cardiac toxicity were dose limiting. Co-administration on day 4 led to a decrease in clearance (p = 0.005) and increase in AUC (p = 0.032) of 17-amino-17-demethoxygeldanamycin (17-AG), not observed when 17-AAG was administered alone. Pharmacokinetic parameters of patients who developed toxicities and those who did not were not different. The combination of 17-AAG and bortezomib led to toxicity without measurable response in patients with relapsed or refractory AML. Pharmacokinetic data provide insight for studies of related agents in AML. Next-generation HSP90 inhibitors are appealing for further development in this area.

A dose escalation and pharmacodynamic study of triapine and radiation in patients with locally advanced pancreas cancer.

PURPOSE: Triapine, a novel inhibitor of the M2 subunit of ribonucleotide reductase (RR), is a potent radiosensitizer. This phase 1 study, sponsored by the National Cancer Institute Cancer Therapy Evaluation Program, assessed the safety and tolerability of triapine in combination with radiation (RT) in patients with locally advanced pancreas cancer (LAPCA). METHODS AND MATERIALS: We evaluated 3 dosage levels of triapine (24 mg/m2, 48 mg/m2, 72 mg/m2) administered with 50.4 Gy of RT in 28 fractions. Patients with LAPCA received triapine thrice weekly, every other week during the course of RT. Dose-limiting toxicity (DLT) was assessed during RT and for 4 weeks after its completion. Dynamic contrast-enhanced magnetic resonance imaging and serum RR levels were evaluated as potential predictors for early response. RESULTS: Twelve patients were treated. Four patients (1 nonevaluable) were enrolled at dosage level 1 (DL1), 3 patients at DL2, and 5 patients (2 nonevaluable) at DL3. No DLTs were observed, and the maximum tolerated dose was not reached. Two patients (17%) achieved partial response, and 6 patients (50%) had stable disease. One patient underwent R0 resection after therapy. Ninety-two percent of patients (100% at DL3) experienced freedom from local tumor progression. In 75% of patients who eventually experienced progression, metastases developed without local progression. RR levels did not seem to predict outcome. In 4 patients with available data, dynamic contrast-enhanced magnetic resonance imaging may predict early response or resistance to therapy. CONCLUSION: The combination of triapine at 72 mg/m2 3 times weekly every other week and standard RT is tolerable with interesting activity in patients with LAPCA.

Clinical and pharmacodynamic activity of bortezomib and decitabine in acute myeloid leukemia.

We recently reported promising clinical activity for a 10-day regimen of decitabine in older AML patients; high miR-29b expression associated with clinical response. Subsequent preclinical studies with bortezomib in AML cells have shown drug-induced miR-29b up-regulation, resulting in loss of transcriptional activation for several genes relevant to myeloid leukemogenesis, including DNA methyltransferases and receptor tyrosine kinases. Thus, a phase 1 trial of bortezomib and decitabine was developed. Nineteen poor-risk AML patients (median age 70 years; range, 32-84 years) enrolled. Induction with decitabine (20 mg/m(2) intravenously on days 1-10) plus bortezomib (escalated up to the target 1.3 mg/m(2) on days 5, 8, 12, and 15) was tolerable, but bortezomib-related neuropathy developed after repetitive cycles. Of previously untreated patients (age ≥ 65 years), 5 of 10 had CR (complete remission, n = 4) or incomplete CR (CRi, n = 1); 7 of 19 overall had CR/CRi. Pharmacodynamic analysis showed FLT3 down-regulation on day 26 of cycle 1 (P = .02). Additional mechanistic studies showed that FLT3 down-regulation was due to bortezomib-induced miR-29b up-regulation; this led to SP1 down-regulation and destruction of the SP1/NF-κB complex that transactivated FLT3. This study demonstrates the feasibility and preliminary clinical activity of decitabine plus bortezomib in AML and identifies FLT3 as a novel pharmacodynamic end point for future trials.

A phase 2 trial of bevacizumab and high-dose interferon alpha 2B in metastatic melanoma.

Bevacizumab is a humanized recombinant monoclonal antibody that neutralizes vascular endothelial growth factor, an agent with proangiogenic effects in melanoma. Interferon alpha (IFN-α) has antiangiogenic properties through its ability to downregulate basic-fibroblast growth factor levels. We hypothesized that the coadministration of these agents would lead to tumor regression. Patients with metastatic melanoma received bevacizumab 15 mg/kg intravenously on day 1 of the 2-week cycle. IFN-α was administered thrice weekly at 5 MU/m subcutaneously during cycle 1 and was increased to 10 MU/m during cycle 2. Patients were restaged every 6 cycles. Patients with stable disease or a response continued with therapy. Baseline serum vascular endothelial growth factor and fibroblast growth factor were measured. Twenty-five patients were accrued. Mean age was 58.4 years. Eleven patients required IFN-α dose reductions due to toxicity. Common grade 3 toxicities associated with IFN-α included fatigue and myalgia. Bevacizumab administration was associated with grade 2-3 proteinuria in 6 patients. Grade 4 adverse events were pulmonary embolus (1), myocardial infarction (1), and stroke (1). Six patients had a partial response, and 5 patients exhibited stable disease that lasted more than 24 weeks (range: 30 to 122 wk). Median progression-free survival and overall survival were 4.8 and 17 months, respectively. Significantly lower fibroblast growth factor levels were observed in patients with a partial response compared to those with stable or progressive disease (P=0.040). Administration of bevacizumab with IFN led to a clinical response in 24% of patients with stage IV melanoma and stabilization of disease in another 20% of patients. This regimen has activity in advanced melanoma.

Dose escalation of lenalidomide in relapsed or refractory acute leukemias.

PURPOSE: Lenalidomide is effective in myeloma and low-risk myelodysplastic syndromes with deletion 5q. We report results of a phase I dose-escalation trial of lenalidomide in relapsed or refractory acute leukemia. PATIENTS AND METHODS: Thirty-one adults with acute myeloid leukemia (AML) and four adults with acute lymphoblastic leukemia (ALL) were enrolled. Lenalidomide was given orally at escalating doses of 25 to 75 mg daily on days 1 through 21 of 28-day cycles to determine the dose-limiting toxicity (DLT) and maximum-tolerated dose (MTD), as well as to provide pharmacokinetic and preliminary efficacy data. RESULTS: Patients had a median age of 63 years (range, 22 to 79 years) and a median of two prior therapies (range, one to four therapies). The DLT was fatigue; 50 mg/d was the MTD. Infectious complications were frequent. Plasma lenalidomide concentration increased proportionally with dose. In AML, five (16%) of 31 patients achieved complete remission (CR); three of three patients with cytogenetic abnormalities achieved cytogenetic CR (none with deletion 5q). Response duration ranged from 5.6 to 14 months. All responses occurred in AML with low presenting WBC count. No patient with ALL responded. Two of four patients who received lenalidomide as initial therapy for AML relapse after allogeneic transplantation achieved durable CR after development of cutaneous graft-versus-host disease, without donor leukocyte infusion. CONCLUSION: Lenalidomide was safely escalated to 50 mg daily for 21 days, every 4 weeks, and was active with relatively low toxicity in patients with relapsed/refractory AML. Remissions achieved after transplantation suggest a possible immunomodulatory effect of lenalidomide, and results provide enthusiasm for further studies in AML, either alone or in combination with conventional agents or other immunotherapies.

Phase I clinical and pharmacokinetic study of a novel schedule of flavopiridol in relapsed or refractory acute leukemias.

BACKGROUND: A pharmacokinetically derived schedule of flavopiridol administered as a 30 min intravenous bolus followed by 4-hour continuous intravenous infusion (IVB/CIVI) is active in fludarabine-refractory chronic lymphocytic leukemia, but no studies examining the feasibility and maximum tolerated dose of this schedule have been reported in acute leukemia. DESIGN AND METHODS: We conducted a phase I dose escalation trial of single-agent flavopiridol in adults with relapsed/refractory acute leukemias, utilizing a modification of the intravenous bolus/continuous intravenous infusion approach, intensifying treatment for administration on days 1, 2, and 3 of 21-day cycles. RESULTS: Twenty-four adults with relapsed/refractory acute myeloid leukemia (n=19) or acute lymphoblastic leukemia (n=5) were enrolled. The median age was 62 years (range, 23-78). The maximum tolerated dose of flavopiridol was 40 mg/m(2) intravenous bolus plus 60 mg/m(2) continuous intravenous infusion (40/60). The dose limiting toxicity was secretory diarrhea. Life-threatening hyperacute tumor lysis syndrome requiring hemodialysis on day 1 was observed in one patient. Pharmacokinetics were dose-dependent with increased clearance observed at the two highest dose levels. Diarrhea occurrence and severity significantly correlated with flavopiridol concentrations at the end of the 4-hour infusion, volume of distribution, and elimination half-life. Modest anti-leukemic activity was observed, with most patients experiencing dramatic but transient reduction/clearance of circulating blasts lasting for 10-14 days. One refractory acute myeloid leukemia patient had short-lived complete remission with incomplete count recovery. CONCLUSIONS: Flavopiridol as a single agent given by intravenous bolus/continuous intravenous infusion causes marked, immediate cytoreduction in relapsed/refractory acute leukemias, but objective clinical responses were uncommon. With this schedule, the dose is limited by secretory diarrhea.

Clinical response and miR-29b predictive significance in older AML patients treated with a 10-day schedule of decitabine.

A phase II clinical trial with single-agent decitabine was conducted in older patients (>or=60 years) with previously untreated acute myeloid leukemia (AML) who were not candidates for or who refused intensive chemotherapy. Subjects received low-dose decitabine at 20 mg/m(2) i.v. over 1 h on days 1 to 10. Fifty-three subjects enrolled with a median age of 74 years (range, 60-85). Nineteen (36%) had antecedent hematologic disorder or therapy-related AML; 16 had complex karyotypes (>or=3 abnormalities). The complete remission rate was 47% (n = 25), achieved after a median of three cycles of therapy. Nine additional subjects had no morphologic evidence of disease with incomplete count recovery, for an overall response rate of 64% (n = 34). Complete remission was achieved in 52% of subjects presenting with normal karyotype and in 50% of those with complex karyotypes. Median overall and disease-free survival durations were 55 and 46 weeks, respectively. Death within 30 days of initiation of treatment occurred in one subject (2%), death within 8 weeks in 15% of subjects. Given the DNA hypomethylating effect of decitabine, we examined the relationship of clinical response and pretreatment level of miR-29b, previously shown to target DNA methyltransferases. Higher levels of miR-29b were associated with clinical response (P = 0.02). In conclusion, this schedule of decitabine was highly active and well tolerated in this poor-risk cohort of older AML patients. Levels of miR-29b should be validated as a predictive factor for stratification of older AML patients to decitabine treatment.

Single-agent lenalidomide induces complete remission of acute myeloid leukemia in patients with isolated trisomy 13.

Patients with acute myeloid leukemia (AML) frequently fail chemotherapy due to refractory disease, relapse, or toxicity. Among older AML patients (age > 60 years), there are few long-term survivors. Lenalidomide is a candidate for study in AML based on its clinical activity in a related disorder, myelodysplastic syndrome (MDS), with the 5q- chromosomal abnormality. We report induction of sustained morphologic and cytogenetic complete remission in 2 older AML patients treated with high-dose, single-agent lenalidomide; each patient had trisomy 13 as the sole cytogenetic abnormality. We show for the first time that lenalidomide has clinical activity in this poor-risk cytogenetic subset of AML. The clinical trials described in this paper have been registered with www.clinicaltrials.gov under identifiers NCT00466895 and NCT00546897.

Phase I study of GTI-2040, an antisense to ribonucleotide reductase, in combination with high-dose cytarabine in patients with acute myeloid leukemia.

PURPOSE: Inhibition of ribonucleotide reductase reduces the availability of the endogenous pool of deoxycytidine and may increase cytarabine (AraC) cytotoxicity. We performed a phase I dose escalation trial of AraC combined with GTI-2040, a 20-mer antisense oligonucleotide shown in preclinical studies to decrease levels of the R2 subunit of ribonucleotide reductase, to determine the maximum tolerated dose in adults with relapsed/refractory acute myeloid leukemia. EXPERIMENTAL DESIGN: Twenty-three adults (ages 18-59 years) were enrolled in this dose escalation phase I trial, receiving high-dose AraC twice daily combined with infusional GTI-2040. An ELISA-based assay measured plasma and intracellular concentrations of GTI-2040. R2 protein changes were evaluated by immunoblotting in pretreatment and post-treatment bone marrow samples. RESULTS: The maximum tolerated dose was 5 mg/kg/d GTI-2040 (days 1-6) and 3 g/m2/dose AraC every 12 hours for 8 doses. Neurotoxicity was dose limiting. Eight patients (35%) achieved complete remission. Mean bone marrow intracellular concentration of GTI-2040 were higher at 120 hours than at 24 hours from the start of GTI-2040 (P = 0.002), suggesting intracellular drug accumulation over time. Reductions in bone marrow levels of R2 protein (>50%) were observed at 24 and 120 hours. Higher baseline R2 protein expression (P = 0.03) and reductions after 24 hours of GTI-2040 (P = 0.04) were associated with complete remission. CONCLUSIONS: GTI-2040 and high-dose AraC were coadministered safely with successful reduction of the intended R2 target and encouraging clinical results. The clinical efficacy of this combination will be tested in an upcoming phase II study.

Higher doses of lenalidomide are associated with unacceptable toxicity including life-threatening tumor flare in patients with chronic lymphocytic leukemia.

PURPOSE: Lenalidomide is a novel therapeutic agent with uncertain mechanism of action that is clinically active in myelodysplastic syndrome (MDS) and multiple myeloma (MM). Application of high (MM) and low (MDS) doses of lenalidomide has been reported to have clinical activity in CLL. Herein, we highlight life-threatening tumor flare when higher doses of lenalidomide are administered to patients with CLL and provide a potential mechanism for its occurrence. PATIENTS AND METHODS: Four patients with relapsed CLL were treated with lenalidomide (25 mg/d for 21 days of a 28-day cycle). Serious adverse events including tumor flare and tumor lysis are summarized. In vitro studies examining drug-induced apoptosis and activation of CLL cells were also performed. RESULTS: Four consecutive patients were treated with lenalidomide; all had serious adverse events. Tumor flare was observed in three patients and was characterized by dramatic and painful lymph node enlargement resulting in hospitalization of two patients, with one fatal outcome. Another patient developed sepsis and renal failure. In vitro studies demonstrated lenalidomide-induced B-cell activation (upregulation of CD40 and CD86) corresponding to degree of tumor flare, possibly explaining the tumor flare observation. CONCLUSION: Lenalidomide administered at 25 mg/d in relapsed CLL is associated with unacceptable toxicity; the rapid onset and adverse clinical effects of tumor flare represent a significant limitation of lenalidomide use in CLL at this dose. Drug-associated B-cell activation may contribute to this adverse event. Future studies with lenalidomide in CLL should focus on understanding this toxicity, investigating patients at risk, and investigating alternative safer dosing schedules.

Phase I study of decitabine alone or in combination with valproic acid in acute myeloid leukemia.

PURPOSE: To determine an optimal biologic dose (OBD) of decitabine as a single agent and then the maximum-tolerated dose (MTD) of valproic acid (VA) combined with decitabine in acute myeloid leukemia (AML). PATIENTS AND METHODS: Twenty-five patients (median age, 70 years) were enrolled; 12 were untreated and 13 had relapsed AML. To determine an OBD (based on a gene re-expression end point), 14 patients received decitabine alone for 10 days. To determine the MTD, 11 patients received decitabine (at OBD, days 1 through 10) plus dose-escalating VA (days 5 through 21). RESULTS: The OBD of decitabine was 20 mg/m(2)/d intravenously, with limited nonhematologic toxicity. In patients treated with decitabine plus VA, dose-limiting encephalopathy occurred in two of two patients at VA 25 mg/kg/d and one of six patients at VA 20 mg/kg/d. Drug-induced re-expression of estrogen receptor (ER) was associated with clinical response (P < or = .05). ER promoter demethylation, global DNA hypomethylation, depletion of DNA methyltransferase enzyme, and histone hyperacetylation were also observed. In an intent-to-treat analysis, the response rate was 44% (11 of 25). Of 21 assessable patients, 11 (52%) responded: four with morphologic and cytogenetic complete remission (CR; each had complex karyotype), four with incomplete CR, and three with partial remission. In untreated AML, four of nine assessable patients achieved CR. Clinical responses appeared similar for decitabine alone or with VA. CONCLUSION: Low-dose decitabine was safe and showed encouraging clinical and biologic activity in AML, but the addition of VA led to encephalopathy at relatively low doses. On the basis of these results, additional studies of decitabine (20 mg/m(2)/d for 10 days) alone or with an alternative deacetylating agent are warranted.

A randomized phase 2 trial of bevacizumab with or without daily low-dose interferon alfa-2b in metastatic malignant melanoma.

BACKGROUND: Vascular endothelial growth factor (VEGF) is a proangiogenic molecule produced by melanoma cells. We hypothesized that administration of bevacizumab (Bev), a monoclonal antibody that neutralizes VEGF, with low-dose interferon alfa-2b (IFN-alpha2b), an inhibitor of basic fibroblast growth factor (FGF), would lead to the regression of metastatic melanoma. METHODS: Patients with metastatic melanoma were randomized to receive Bev (15 mg/kg intravenously every 2 weeks) with or without low-dose IFN-alpha2b (1 MU/m2 subcutaneously daily). Patients exhibiting a clinical response or stable disease after 12 weeks were treated until disease progression. RESULTS: Thirty-two patients (16 per arm) were accrued (18 male, 14 female; mean age 57.5 years). Both regimens were well tolerated. Six patients developed easily managed exacerbations of preexisting hypertension. Two patients developed grade 3 proteinuria that resolved after a treatment break. IFN-alpha2b therapy was associated with grade 1 to 2 constitutional symptoms. Arterial thromboembolic complications were observed in three patients (two mild myocardial infarctions, one transient ischemic attack), all of whom had risk factors. One patient (Bev plus IFN-alpha2b arm) had locally recurrent scalp disease that partially responded to therapy. Eight patients (five Bev, three Bev plus IFN-alpha2b) had prolonged disease stabilization (24 to 146 weeks). Plasma levels of VEGF and FGF did not correlate with any clinical parameter. The patient with the longest period of stable disease had the highest baseline VEGF and FGF. CONCLUSIONS: Bev was well tolerated at this dose and prolonged disease stabilization was achieved in one-quarter of metastatic melanoma patients. Low-dose IFN-alpha2b did not augment the activity of Bev.

Phase I study of oblimersen sodium, an antisense to Bcl-2, in untreated older patients with acute myeloid leukemia: pharmacokinetics, pharmacodynamics, and clinical activity.

PURPOSES: Pharmacologic downregulation of Bcl-2, an antiapoptotic protein overexpressed in cancer, might increase chemosensitivity in acute myeloid leukemia (AML). Herein, we investigated the feasibility of this approach in untreated elderly AML patients by administering oblimersen sodium (G3139), an 18-mer phosphorothioate antisense to Bcl-2, during induction and consolidation treatments. PATIENTS AND METHODS: Untreated patients with primary or secondary AML (stratified to cohort 1 or 2, respectively) who were > or = 60 years received induction with G3139, cytarabine, and daunorubicin at one of two different dose levels (45 and 60 mg/m2) and, on achievement of complete remission (CR), consolidation with G3139 and high-dose cytarabine. An enzyme-linked immunosorbent assay (ELISA)-based assay was used to measure plasma and intracellular concentrations (IC) of G3139. Bcl-2 mRNA and protein levels were quantified by real-time reverse transcriptase polymerase chain reaction and ELISA, respectively, in bone marrow samples collected before induction treatment and after 72 hours of G3139 infusion, prior to initiation of chemotherapy. RESULTS: Of the 29 treated patients, 14 achieved CR. With a median follow-up of 12.6 months, seven patients had relapsed. Side effects of this combination were similar to those expected with chemotherapy alone and were not dose limiting at both dose levels. After 72-hour G3139 infusion, Bcl-2/ABL mRNA copies were decreased compared with baseline (P = .03) in CR patients and increased in nonresponders (NRs; P = .05). Changes in Bcl-2 protein showed a similar trend. Although plasma pharmacokinetics did not correlate with disease response, the median IC of the antisense was higher in the CR patients compared with NRs (17.0 v 4.4 pmol/mg protein, respectively; P = .05). CONCLUSION: G3139 can be administered safely in combination with intensive chemotherapy, and the degree of Bcl-2 downmodulation may correlate with response to therapy.