A phase 1 study of ruxolitinib, steroids and lenalidomide for relapsed/refractory multiple myeloma patients

Ruxolitinib with lenalidomide and dexamethasone shows anti-myeloma effects in vitro and in vivo. MUC1 leads to lenalidomide resistance in multiple myeloma (MM) cells, and ruxolitinib blocks its expression. Thus, ruxolitinib may restore sensitivity to lenalidomide. A phase I trial was conducted to determine the safety and efficacy of ruxolitinib with lenalidomide and methylprednisolone for patients with relapsed/refractory (RR)MM who had been treated with lenalidomide, steroids and a proteasome inhibitor and showed progressive disease at study entry. A traditional 3 + 3 dose escalation design was used to enroll subjects in four cohorts. Subjects received ruxolitinib twice daily, lenalidomide daily on days 1-21 of a 28 day cycle and methylprednisolone orally every other day. Primary endpoints were safety, clinical benefit rate (CBR) and overall response rate (ORR). Forty-nine patients were enrolled. The median age was 64 years and they had received a median of six prior treatments including lenalidomide and steroids to which 94% were refractory. No dose limiting toxicities occurred. The CBR and ORR were 49% and 36%, respectively. All responding patients were refractory to lenalidomide. Grade 3 or 4 adverse events (AEs) included anemia (17%), decreased lymphocyte count (15%), and hypophosphatemia (10%). Most common serious AEs included sepsis (9.8%) and pneumonia (7.8%). This Phase I trial demonstrates that a JAK inhibitor, ruxolitinib, can overcome refractoriness to lenalidomide and steroids for patients with RRMM. These results represent a promising novel therapeutic approach for treating MM. NCT03110822.

Use of serum B-cell maturation antigen levels to predict outcomes for myeloma patients treated with ruxolitinib, lenalidomide and methylprednisolone

Previous retrospective studies have shown that serum B-cell maturation antigen (sBCMA) levels predict outcomes among patients with multiple myeloma (MM) undergoing new treatments. Specifically, baseline levels and changes during treatment of this protein predict both progression free survival (PFS) and overall survival. However, prospective studies are lacking evaluating sBCMA for determining outcomes among MM patients undergoing new treatments. Thus, we evaluated whether its baseline levels and changes during treatment in the amount of this serum marker predict outcomes among 38 relapsed/refractory MM patients treated with ruxolitinib, lenalidomide and methylprednisolone in a phase 1 trial. Patients with baseline sBCMA levels in the lowest three quartiles had longer PFS (median PFS 136 vs. 28 days; p < 0.0001). This was also shown for patients with baseline levels below the median (median PFS 140 vs. 77 days; p = 0.0225). PFS was shorter for patients whose sBCMA levels increased ≥25% through their first cycle (median PFS: 50 vs. 134 days, p = 0.0022), second cycle (median PFS: 50 vs. 141 days, p = 0.0273), and during the first three cycles of study treatment (median PFS: 50 vs. 220 days, p < 0.0001). No patient whose sBCMA increased ≥25% during cycle 1 responded whereas the majority (58%) of patients whose level increased <25% responded. This is the first prospective study to determine whether sBCMA levels predict outcomes for MM patients undergoing a non-BCMA directed treatment regimen and demonstrates that baseline levels and its changes during treatment predict PFS and the likelihood of responding to their treatment. These results add to the growing literature suggesting that this serum marker will be useful for determining outcomes for patients undergoing treatment for MM.

A phase 2 trial of the efficacy and safety of elotuzumab in combination with pomalidomide, carfilzomib and dexamethasone for high-risk relapsed/refractory multiple myeloma

High-risk multiple myeloma (MM) continues to have a poor prognosis and remains a therapeutic challenge. This phase 2 study evaluated the efficacy and safety of elotuzumab in combination with pomalidomide, carfilzomib, and low-dose dexamethasone for patients with high-risk relapsed/refractory (RR)MM (NCT03104270). Of 13 enrolled patients, 11 were evaluable for efficacy. Overall response rate and clinical benefit rate were 45.4% and 54.5%, respectively. Deep responses were observed including two complete responses. The novel quadruplet combination was overall well-tolerated, with clinically manageable adverse events. Common adverse events of ≥ grade 3 included lymphopenia (15%), anemia (15%), sepsis (15%), pneumonia (15%), and hypophosphatemia (15%). The novel combination showed promising efficacy and was well tolerated in this heavily pretreated MM population. Even though the study was terminated early prior to completion of enrollment, the results indicate that this may be a promising therapeutic approach for high-risk RRMM patients, which warrants further study.

Baseline serum B-cell maturation antigen levels predict time to disease progression for patients with smoldering multiple myeloma

Multiple myeloma (MM) patients with smoldering (S) disease are defined by a lack of CRAB/SLiM criteria but may transform into disease requiring treatment. The International Myeloma Working Group risk stratification model for SMM uses serum M-protein, serum-free light chain ratio, and bone marrow plasma cell percentage. We investigated whether baseline serum B-cell maturation antigen (sBCMA) levels are predictive of disease progression among 65 patients with SMM. A receiver operating characteristic curve was used to establish a definition for high-risk baseline sBCMA. Mantel Byar analysis was used to examine whether high-risk sBCMA was correlated with shorter time to transformation, and a time-dependent cox proportional hazard was used to determine whether it is independent of other risk factors. A z test for proportions was used to compare the percentage of patients that progressed among high-risk versus low-risk sBCMA patients. A baseline sBCMA level ≥137.5 mg/ml was found to be the optimal cutoff between high- and low-risk SMM patients. Patients with high-risk sBCMA levels had a shorter time to transformation (P = .000332). sBCMA was also higher at the time of transformation than baseline levels (P = .0116). sBCMA was the only variable found to be significantly predictive of time to transformation and additionally was found to be independent of other risk factors. In this study, we have shown for the first time that sBCMA levels predict transformation of SMM to active disease and that these levels increase at the time of transformation. These results are consistent with other studies showing that active MM patients undergoing therapy with higher baseline sBCMA levels are more likely to progress early and its levels increase at the time of disease progression.

A Phase I Study of Ruxolitinib, Lenalidomide, and Steroids for Patients with Relapsed/Refractory Multiple Myeloma

PURPOSE

Ruxolitinib with lenalidomide and dexamethasone shows antimyeloma effects in vitro and in vivo. MUC1 leads to lenalidomide resistance in multiple myeloma cells, and ruxolitinib blocks its expression. Thus, ruxolitinib may restore sensitivity to lenalidomide. Therefore, a phase I trial was conducted to determine the safety and efficacy of ruxolitinib with lenalidomide and methylprednisolone for patients with relapsed/refractory multiple myeloma (RRMM) who had been treated with lenalidomide/steroids and a proteasome inhibitor and showed progressive disease at study entry.

PATIENTS AND METHODS

A traditional 3+3 dose escalation design was used to enroll subjects in four cohorts with planned total enrollment of 28 patients. Subjects received ruxolitinib twice daily, lenalidomide daily on days 1-21 of a 28-day cycle, and methylprednisolone orally every other day. Primary endpoints were safety, clinical benefit rate (CBR), and overall response rate (ORR).

RESULTS

Twenty-eight patients were enrolled. The median age was 67 years and received a median of six prior treatments including lenalidomide and steroids to which 93% were refractory. No dose-limiting toxicities occurred. The CBR and ORR were 46% and 38%, respectively. All 12 responding patients were refractory to lenalidomide. Grade 3 or grade 4 adverse events (AE) included anemia (18%), thrombocytopenia (14%), and lymphopenia (14%). Most common serious AEs included sepsis (11%) and pneumonia (11%).

CONCLUSIONS

This phase I trial demonstrates that a JAK inhibitor, ruxolitinib, can overcome refractoriness to lenalidomide and steroids for patients with RRMM. These results represent a promising novel therapeutic approach for treating multiple myeloma (ClinicalTrials.gov number, NCT03110822).

A phase I trial of ruxolitinib, lenalidomide, and methylprednisolone for patients with relapsed/refractory multiple myeloma (MM)

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Background: Preclinical studies from our laboratory have demonstrated that ruxolitinib (RUX) in combination with lenalidomide (LEN) and dexamethasone shows marked anti-myeloma effects both in vitro and in vivo. Furthermore, MUC1 is responsible for LEN resistance in MM cells, and RUX blocks its expression in MM cells. Thus, RUX may restore sensitivity to LEN. Therefore, a phase 1 trial was conducted to determine the safety and efficacy of RUX in combination with LEN and methylprednisolone (MP) for relapsed/refractory (RR) MM patients (pts) who had previously been treated with LEN/steroids and a proteasome inhibitor (PI) and showed progressive disease at study entry. Methods: A traditional 3+3 dose escalation design was used to enroll subjects in four cohorts with planned total enrollment to be 49 pts. Subjects received RUX twice daily continuously, LEN daily on d1-21 of a 28-d cycle and MP orally every other day. In DL0, pts received RUX 5 mg, LEN 5 mg, and MP 40 mg. In DL+1 and +2, both doses of LEN and MP remained unchanged and RUX was escalated to 10 and 15 mg, respectively. DL+3 escalated LEN to 10 mg with MP unchanged and RUX at 15 mg. Primary endpoints were safety, clinical benefit rate (CBR) and overall response rate (ORR). Results: As of September 1, 2018, 36 pts were enrolled, and 32 were evaluable for efficacy. The median age was 66 years (range, 46-81), and 21 (58%) were male. Pts received a median of 6 prior treatments including LEN and steroids to which they were all refractory and a proteasome inhibitor. No DLTs occurred, and DL+3 was expanded. Among evaluable pts, the CBR and ORR were 47% and 41%, respectively (1 CR, 2 VGPR, 10 PR and 2 MR), and 14 and 3 pts showed SD and PD. All 15 responding pts were refractory to LEN. G3 AEs included anemia (17%), neutropenia (14%), sepsis (14%), lymphocytopenia (11%), thrombocytopenia (11%), and pneumonia (11%). Most common SAEs included sepsis (14%) and pneumonia (11%). Conclusions: This Ph 1 trial demonstrates for the first time that a JAK inhibitor, RUX, can overcome refractoriness to LEN and steroids for RR MM pts. These promising results are leading to expansion of the current clinical trial to 78 pts, and represents a novel therapeutic approach for treating MM. Clinical trial information: NCT03110822.

Analysis of efficacy and safety of POM as a replacement therapy for lenalidomide for relapsed/refractory multiple myeloma pts refractory to a lenalidomide-containing combination regimen

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Background: Pomalidomide (POM) is a third –generation immunomodulatory drug shown to be safe and effective for the treatment of relapsed/refractory multiple myeloma (RRMM) for patients (pts) previously treated with bortezomib and lenalidomide (LEN) and in combination with dexamethasone it has been shown to overcome resistance in RRMM. In this phase 2 trial, we are evaluating the efficacy, safety and tolerability of POM as a replacement therapy for LEN for pts who have progressed receiving a LEN combination regimen. Methods: This is a phase 2, multicenter, open-label and non-randomized study. Pts who have failed a combination regimen containing LEN were treated with POM along with all of the other drugs previously used in the regimen. POM administered orally (dose is determined based on the previous regimen) on days 1-21 of a 28-day cycle, whereas other drugs are administered using the same schedule(s), dose(s) and drug combination as the last LEN-containing regimen that the patient received and failed. The planned enrollment on the study will be 45 pts. Results: To date, a total of 29 pts have been enrolled, 25 pts are evaluable and 12 pts have discontinued treatment. Of the evaluable pts, 9 (36%) and 16 (64%) received 3mg and 4mg of POM, respectively. The median age of all pts was 72 years (range, 52-81), and 17 (68%) were males. Pts have received a median of 3 prior treatments (range, 1-7). The median follow-up time for all pts is 3.1 months (range, 0.2-8.1). Amongst evaluable pts, 5 (23.8%) pts achieved at least a minimal response, 10 (47.6%) pts showed stable disease while 6 (28.6%) pts exhibited disease progression. At the time of data cutoff, only 17 pts have completed more than 1 full cycle of treatment; and, thus, the overall response and clinical benefit rates are fairly low (14.3% and 23.8%, respectively) but expected to improve with further follow up. The median PFS for the cohort was 7.6 months. Common ≥ Gr3 adverse events were neutropenia (8%), hypomania (4%) and leukopenia (4%). Conclusions: We show thatPOM appears to be promising replacement therapy for LEN in RRMM pts who have progressed within receiving a LEN combination regimen.

Replacement of ixazomib for relapsed/refractory multiple myeloma patients refractory to a bortezomib or carfilzomib-containing combination therapy

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Background: The proteasome inhibitor (PI) ixazomib (Ixz) is the first orally administered PI approved for treating multiple myeloma (MM). It has shown clinical activity as a single agent and when used in other combinations. In this phase 1/2 trial, we evaluated Ixz as a replacement therapy for bortezomib or carfilzomib for MM patients who were refractory to a bortezomib- or carfilzomib-containing combination regimen. Methods: This was a phase 1/2, intra-patient, multicenter, open-label trial evaluating the replacement of ixazomib for bortezomib or carfilzomib for MM patients who were refractory in combination with the other agents that the patients had received and failed. Patients received Ixz on days 1, 8 and 15 on a 28-day schedule and the other drugs were administered using the same doses and schedules as they were receiving during their prior regimen. If the Ixz maximum tolerated dose (MTD) for a particular combination regimen was previously determined, then patients were enrolled directly into Phase 2 (PhII). If not, MTD was determined during the Phase 1 (PhI) portion of the trial. Results: To date, a total of 40 patients have been enrolled; 37 patients (21 were enrolled in PhI and 16 in PhII) had completed at least one cycle of this treatment. Patients received a median of 5 prior treatments (range, 1-22). The median follow-up time for all patients was 1.6 months (range, 0.1-10.7 months), whereas that of PhII was 2.2 months (range, 0.2-10.7 months). There was no clinical benefit (CBR; 0%) nor any overall response rate (ORR; 0%) for patients receiving Ixz 3 mg (PhI). Nine patients (43%) showed stable disease (SD) while 12 (57%) exhibited disease progression (PD). In PhII (4mg Ixz) portion of the trial, ORR and CBR were both 18.7% with 16 (43.2%) patients showing SD, and 18 (48.6%) patients displaying PD. Common ≥ Gr3 adverse events were anemia (11%), thrombocytopenia (5.4%), hyponatremia (5.4%), dehydration (5.4%) and neutropenia (2.7%). Conclusions: Replacement of bortezomib or carfilzomib with Ixz infrequently leads to responses among RRMM patient who have progressed while on proteasome inhibitor -containing combination regimens. Clinical trial information: NCT02206425.

Serum B-cell maturation antigen: a novel biomarker to predict outcomes for multiple myeloma patients

B-cell maturation antigen is expressed on plasma cells. In this study, we have identified serum B-cell maturation antigen as a novel biomarker that can monitor and predict outcomes for multiple myeloma patients. Compared to healthy donors, patients with multiple myeloma showed elevated serum B-cell maturation antigen levels (P<0.0001). Serum B-cell maturation antigen levels correlated with the proportion of plasma cells in bone marrow biopsies (Spearman's rho = 0.710; P<0.001), clinical status (complete response vs partial response, P=0.0374; complete response vs progressive disease, P<0.0001), and tracked with changes in M-protein levels. Among patients with non-secretory disease, serum B-cell maturation antigen levels correlated with bone marrow plasma cell levels and findings from positron emission tomography scans. Kaplan-Meier analysis demonstrated that serum B-cell maturation antigen levels above the median levels were predictive of a shorter progression-free survival (P=0.0006) and overall survival (P=0.0108) among multiple myeloma patients (n=243). Specifically, patients with serum B-cell maturation antigen levels above the median level at the time of starting front-line (P=0.0043) or a new salvage therapy (P=0.0044) were found to have shorter progression-free survival. Importantly, serum B-cell maturation antigen levels did not show any dependence on renal function and maintained independent significance when tested against other known prognostic markers for multiple myeloma such as age, serum β2 microglobulin, hemoglobin, and bone disease. These data identify serum B-cell maturation antigen as a new biomarker to manage multiple myeloma patients.

Low serum vitamin D occurs commonly among multiple myeloma patients treated with bortezomib and/or thalidomide and is associated with severe neuropathy

PURPOSE

Previous studies have shown that low serum vitamin D levels have been associated with many skeletal and non-skeletal disorders. We studied the relationship between 25-hydroxyvitamin D (25D) levels and motor and sensory peripheral neuropathy (PN) among multiple myeloma (MM) patients who have been treated with bortezomib and/or thalidomide.

METHODS

We performed a study of 111 MM patients who had received at least one of these two agents for at least 12 weeks by correlating physical exam/neurologic assessment findings with patient self-assessment responses.

RESULTS

The median age of study patients was 66 years (range 42-89 years) and 54 % were males. 25D levels were determined, and complete history and physical and neurologic examinations were performed at the same study visit. In addition, study subjects completed questionnaires regarding symptoms related to motor and sensory PN. Overall, patients had a median serum 25D level of only 32 ng/ml; 42 % of patients were considered either 25D-deficient (<20.0 ng/mL; 16 % of patients) or 25D-insufficient (20.0-29.9 ng/mL; 26 %). Notably, we found that 25D-deficient MM patients were more likely to have severe PN (>grade 2) of both motor (p = 0.0415) and sensory (p = 0.0086) types although the overall incidence of PN was not higher in this patient population.

CONCLUSION

These results show that the severity of peripheral neuropathy is associated with lower vitamin D levels and provides the rationale for monitoring vitamin D for myeloma patients especially those receiving drugs associated with the development of peripheral neuropathy.

A phase 3 trial of armodafinil for the treatment of cancer-related fatigue for patients with multiple myeloma

PURPOSE

Fatigue is a common problem among multiple myeloma (MM) patients. Armodafinil is a drug known to promote wakefulness, which is related to modafinil, a compound that improves fatigue in some cancer patients treated with chemotherapeutic agents. We investigated whether armodafinil could reduce cancer-related fatigue in MM patients.

METHODS

This double-blind, placebo-controlled phase 3 trial evaluated the efficacy of armodafinil in MM patients with evidence of moderate fatigue. Patients were randomized to one of two arms: treatment-only, with armodafinil given at 150 mg/daily for 56 days, or placebo-first, with placebo given on days 1-28, followed by armodafinil administered at 150 mg daily on days 29-56. Fatigue was measured on days 1 (pre-dose: baseline), 15, 28, 43, and 56 using seven separate assessments, including four patient-reported outcomes of fatigue and related quality of life measures, as well as three objective measures of cognitive function.

RESULTS

Overall toxicities were similar between treatment groups. No significant differences were observed between the placebo-first and the treatment-only arms after 28 days. Treatment with armodafinil for 28 additional days did not produce responses. Both placebo-first and treatment-only patients showed similar significant improvements in three patient-reported measures and one objective task at day 28 compared to baseline. Placebo-first patients improved on eight additional measures (one patient-reported measure, six subscales, and one objective task), suggesting a strong placebo effect in this patient population.

CONCLUSIONS

Evaluation and treatment of cancer-related fatigue continues to be challenging; a clear definition of this symptom and better assessment tools are needed.

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)

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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.

Risk of skin cancer in multiple myeloma patients: A retrospective cohort study

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Background: Multiple myeloma (MM) patients (pts) have shown a higher risk of developing other cancers, although the type, time course, and relationship to MM treatment of these cancers are less clear. In this study, we determined the risk of specific skin cancer (CA) types among MM patients and its relationship to onset of MM and treatment. Methods: MM pts and unrelated age, sex, and race-matched companions (controls) seen at a MM clinic were enrolled in a retrospective cohort study. Information regarding baseline characteristics of MM and history of skin CA was obtained from medical records. Overall skin CA prevalence and types were compared between groups; among MM patients, the occurrence of skin CA was analyzed relative to date of diagnosis and treatment regimens, with stratification according to treatment duration. Results: We enrolled 205 MM pts and 201 controls with 27.3% and 14.9% demonstrating skin CA, respectively (p < 0.001). Specific types of skin CA included 60 and 37 basal cell carcinomas (BCC), 50 and 17 squamous cell carcinomas (SCC), and 9 and 5 melanomas in the MM pts and controls, respectively. The standardized incidence ratios (SIR) were SCC: 2.88 (p< 0.001), BCC: 1.59 (p<0.001), and melanoma: 1.76 (p = 0.074). SCC SIR was elevated (p<0.001) across each yearly time point from 10 years prior to MM diagnosis through 10 years subsequent to MM diagnosis. BCC SIR was elevated (p <0.002) from 7 through 10 years following MM diagnosis. The SIR markedly increased over time following the diagnosis of MM for both SCC and BCC. Relative risk (RR) was determined for pts treated with bortezomib, immunomodulatory agents, alkylating agents, glucocorticoids, and anthracyclines. There was no significant increase in RR overall or for any specific type of skin CA in relationship to the type or duration of MM treatment. Conclusions: MM pts show an increased risk of skin CA (there was no increase in melanoma incidence), including SCC and BCC. SCC occurred before and following the diagnosis of MM whereas BCC followed the diagnosis of MM. The post-MM diagnosis increase in skin CA was not related to specific drugs used to treat MM.

A phase I/II study (NCT01541332) of pomalidomide (POM), dexamethasone (DEX), and pegylated liposomal doxorubicin (PLD) for patients with relapsed/refractory (R/R) multiple myeloma (MM)

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Background: POM is a newer IMiD immunomodulatory compound with high in vitro potency that has shown promise in combination with DEX as an effective treatment option for R/R MM patients (pts), even those refractory to bortezomib and lenalidomide (LEN). We conducted a phase I/II trial investigating the safety and efficacy of POM in combination with IV DEX and PLD using a modified dose and longer 28-day schedule in R/R MM pts. Methods: Phase I pts had progressive MM at the time of enrollment that was R/R to at least one anti-MM regimen. Phase II pts had to be refractory to LEN (singe-agent or in combination) demonstrated by progressive disease while receiving LEN or relapse within 8 weeks of its last dose. During phase I, POM was administered orally at 2, 3, or 4 mg daily in 3 successive cohorts of 3 pts each on days 1-21 of each 28-day cycle. DEX was administered IV at 40 mg over 30 min and PLD was administered at 5 mg/m2as an IV infusion over 30-90 min on days 1, 4, 8, and 11 of each cycle. POM doses were escalated until maximum tolerated dose (MTD) was reached. Once MTD was reached, all subsequent pts were enrolled at that dose. Results: To date, 27 pts have been enrolled, with 18 evaluable for efficacy and 19 for safety. Pts received a median of 5 prior treatments (range, 1-18) with a median of 1 prior PLD regimens (range, 0-2). Pts have completed a median of 1 cycle (range: 0-8) with a median of 1.4 months of follow up (range: 0-7.1). No DLTs were seen during phase I, which established the MTD at 4 mg. Phase II has enrolled 16 pts at 4 mg so far. Clinical benefit was seen in 7 (39%) of evaluable pts (partial response = 22%; minor response = 17%) with another 44% showing stable disease. Common ≥ G3 adverse events included leukopenia (32% of pts), neutropenia (32%), lymphopenia (26%), and hyponatremia (16%). Neutropenia at ≥ G3 occurred in more than half of patients on the phase II trial (4 mg POM). Conclusions: The combination of pomalidomide with dexamethasone and PLD on a 28-day cycle shows efficacy for R/R MM pts. However, because of excessive ≥ G3 neutropenia, POM is being reduced to 3 mg for newly enrolled patients. Clinical trial information: NCT01541332.

Serum B-cell maturation antigen is elevated in multiple myeloma and correlates with disease status and survival

Although TNFRSF17 (also designated as B-cell maturation antigen (BCMA)) is expressed on tumour cells in B-cell malignancies, it has not been found in serum. The present study found that BCMA concentrations were higher in the supernatants of cultured bone marrow mononuclear cells from multiple myeloma (MM) patients than in healthy subjects. Serum BCMA levels were measured in samples from MM patients (n = 209), monoclonal gammopathy of undetermined significance (MGUS) individuals (n = 23) and age-matched controls (n = 40). BCMA was detected in the serum of untreated MM patients (n = 50) and levels were higher than in MGUS patients (P = 0·0157) and healthy subjects (P < 0·0001). Serum BCMA levels were higher among patients with progressive disease (n = 80) compared to those with responsive disease (n = 79; P = 0·0038). Among all MM patients, overall survival was shorter among patients whose serum BCMA levels were above the median (P = 0·001). We also demonstrated that sera from mice with human MM xenografts contained human BCMA, and levels correlated with the change in tumour volume in response to melphalan or cyclophosphamide with bortezomib. These results suggest that serum BCMA levels may be a new biomarker for monitoring disease status and overall survival of MM patients.

A phase I/II study of carfilzomib (CFZ) as a replacement for bortezomib (BTZ) for multiple myeloma (MM) patients (Pts) progressing while receiving a BTZ-containing combination regimen

8098

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 1/2 trial investigating the safety and efficacy of CFZ as a replacement for BTZ in BTZ‑containing regimens to which pts have progressed. Methods: Eligible pts had to have progressed while receiving their most recent BTZ‑containing regimen after at least 4 doses of BTZ at > 1.0 mg/m² in < 4 weeks per cycle. Combination regimens containing an alkylating agent, anthracycline, or a glucocorticosteroid were eligible. 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 BTZ‑containing 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 19 enrolled pts 13 are evaluable to date and 6 have recently started treatment. Pts received a median of 7 (range, 1-18) prior treatments and 5 (range, 1-5) different BTZ-containing regimens. Pts were treated with CFZ and the following different combinations: bendamustine (BEND) alone, BEND + methylprednisolone, dexamethasone (DEX) alone, DEX + pegylated liposomal doxorubicin, ascorbic acid + cyclophosphamide, and melphalan alone. Pts have completed a median of 3 cycles. Clinical benefit was seen in 10 (77%) pts (complete response = 8%; very good partial response = 8%; partial response = 31%; minor response = 31%) with another 23% showing stable disease. The median time to progression (range: 2-8 months) has not been reached and only 2 pts have progressed. The most common grade 3/4 adverse events were thrombocytopenia occurring in 5 pts (all = grade 3 except 1 event) and fever occurring in two pts (grade 3). Four pts experienced a serious adverse event but no regimen has reached a MTD. Conclusions: These early results suggest that CFZ is an effective and tolerable replacement for BTZ for pts who are refractory to BTZ-containing combination regimens.

A phase I/II trial of melphalan (MEL) combined with panobinostat (PAN) for patients with relapsed or refractory (R/R) multiple myeloma (MM)

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Background: PAN, a potent histone deacetylase inhibitor, significantly inhibits the growth of MM cells in vitro and enhances the cytotoxicity of standard chemotherapy. Studies with our SCID-hu MM models show an increased inhibition of MM cell growth when PAN was combined with MEL compared to treatment with either drug alone. These preclinical studies provided the rationale for evaluating the combination of oral MEL with oral PAN for the treatment of MM patients with R/R disease. Methods: This was a Phase 1/2, open-label, dose‑escalation study to treat R/R MM patients initially using oral PAN every Monday, Wednesday and Fridayin combination with oral MEL (0.05 mg/kg) on days 1-5 of a 28‑day cycle. Results: Thirty-seven patients were enrolled into the Phase 1 portion of this study. The median number of prior regimens received were 4 (range, 1-17) with 22 patients previously treated with MEL. Following amendments to dose and schedule because of toxicity including cytopenias and fatigue, PAN and MEL were both administered only on days 1, 3 and 5 of a 28-day cycle. The maximum tolerated dose for this combination was defined as PAN at 20 mg and MEL at 0.05 mg/kg both administered on only days 1, 3 and 5. Overall, 4 patients (11%) showed objective responses to this combination with 1 complete (3%) and 3 partial (8%) responses and only occurred among patients receiving PAN throughout the cycle. An additional 18 (49%) patients had stable disease while 15 (41%) progressed while on study. Eighteen patients experienced grade 3 or 4 adverse events (AEs) with 6 of these meeting the definition of a dose-limiting toxicity. These AEs included reversible thrombocytopenia (n=11), reversible neutropenia (n=10), reversible worsening anemia (n=3), and one case each of a forearm rash, fatigue/weakness, pneumonia, hypokalemia and hyponatremia. Three more patients who are not yet evaluable have been enrolled into the Phase 2 portion to complete the planned 40 patients on the trial. Conclusions: The combination of intermittent PAN & low-dose oral MEL shows modest activity in heavily pretreated patients with R/R MM. Continuous doses of PAN with MEL yielded better efficacy but this treatment schedule was not tolerable.

Evaluation of serum B-cell maturation antigen in multiple myeloma

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Background: B cell maturation antigen (BCMA) is a receptor whose expression increases during B-cell development and is found on malignant cells from multiple myeloma (MM) patients; however, it has not been identified in human serum. Methods: Bone marrow (BM) aspirates and peripheral blood were obtained from patients with MM, monoclonal gammopathy of undetermined significance (MGUS) and healthy control subjects following informed consent (Western IRB BIO 001). Serum was isolated and analyzed with a BCMA enzyme‑linked immunosorbent assay. Values represent the mean of triplicate experiments. BM mononuclear cells (MCs) were isolated using density‑gradient centrifugation and cultured for 72 h in RPMI1640 supplemented with 10% fetal bovine serum. Our human MM xenograft (LAGκ-2)was grown in SCID mice and treated with bortezomib (BORT) with cyclophosphamide (CY); tumor volume and BCMA levels were determined. Statistical significance of differences observed was determined using a Student’s t test and analysis was determined using GraphPad prism software. Results: We showed that the supernatants of cultured BMMCs from MM patients had high concentrations of BCMA (median = 2,250 pg/ml) whereas normal subjects showed minimal amounts (56 ng/ml; P < 0.0001). The serum BCMA levels from newly diagnosed MM patients (n = 51) had much higher levels (13.74 ng/ml) than among controls (n = 40; median 2.58 ng/ml; P < 0.0001) and MGUS subjects (n = 26; median 5.40 ng/ml; P = 0.005). Notably, protein levels were much higher among patients with relapsed or refractory (R/R) disease (n = 79; median 20.02 ng/ml) compared to those with responsive (> partial response) disease (n = 80; median 4.14 ng/ml; P = 0.0038). Following treatment, patients with responsive disease showed decreases in BCMA levels whereas those with R/R disease showed increases. Following treatment with BORT and CY, we also showed a marked decrease in tumor volume and serum human BCMA levels in mice bearing the LAGκ-2 xenograft whereas untreated animals showed marked increases in tumor size and serum BCMA. Conclusions: This is the first report identifying serum BCMA in any human disease and suggests that these levels may be a novel biomarker for monitoring disease status and therapeutic response of MM patients.

Prognostic factors and jaw and renal complications among multiple myeloma patients treated with zoledronic acid

Few studies have evaluated prognostic factors among patients with multiple myeloma (MM) since new therapies have become available. Monthly zoledronic acid (ZOL) has been incorporated into many treatment regimens to reduce skeletal-related events (SREs), but outcomes among patients receiving this bisphosphonate have not been well-defined. The aim of this retrospective study was to determine baseline and on-treatment prognostic factors in these patients. Data were collected from the date of diagnosis on 300 consecutive MM patients treated with ZOL. Median duration of ZOL was 18 months (range 1-121 months). The skeletal morbidity rate was 0.116 events per patient year. Five-year overall survival (OS) was 69%. Risk factors for shortened OS included SREs, increased serum creatinine, and International Staging System (ISS) Stage II or III. Thirty-four (11%) patients showed worsening renal function. In 28 of these patients, ZOL was discontinued and restarted in half of these patients following a brief delay. Only 5 of the 34 patients showed worsening of their renal function. Fourteen patients (4.7%) developed osteonecrosis of the jaw (ONJ). All patients with ONJ are in remission or with stable disease except one patient who died of a myocardial infarction while in remission. Only two patients showed some worsening of ONJ despite of ongoing monthly ZOL. Overall, these results suggest that skeletal complications are an important prognostic factor for MM. Although ONJ and renal deterioration may infrequently occur with ZOL, most patients do not experience worsening of these conditions with ongoing treatment with this bisphosphonate.

Bortezomib, ascorbic acid and melphalan (BAM) therapy for patients with newly diagnosed multiple myeloma: an effective and well-tolerated frontline regimen

BACKGROUND

We conducted a single-arm, multicentre phase 2 study to evaluate bortezomib, ascorbic acid and melphalan (BAM) for patients with newly diagnosed multiple myeloma (MM).

METHODS

Induction consisted of up to eight 28-d cycles of bortezomib 1.0 mg/m(2) on days 1, 4, 8 and 11, plus oral ascorbic acid 1 g and oral melphalan 0.1 mg/kg on days 1-4, followed by maintenance bortezomib 1.3 mg/m(2) every 2 wk until progression.

RESULTS

Among 35 patients enrolled (median age 70 yr), responses occurred in 23/31 evaluable patients (74%) including five (16%) complete, three (10%) very good partial, six (19%) partial and nine (29%) minimal responses. Six patients (19%) had stable disease. Thus, disease control was achieved in 29 (94%) patients. Median times to first and best responses were 2 and 3 months (ranges 1-5 and 1-7), respectively. Median time to progression was 19 months and median overall survival has not been reached (range 2-23+ months). Grade 3 and 4 adverse events occurred in 17 and 5 patients, respectively; the most common were neutropenia, neuropathy and thrombocytopenia.

CONCLUSIONS

BAM is an efficacious, well-tolerated and steroid- and immunomodulatory drug (IMiD)-free frontline treatment regimen for MM patients.

Zoledronic acid markedly improves bone mineral density for patients with monoclonal gammopathy of undetermined significance and bone loss

PURPOSE

Patients with monoclonal gammopathy of undetermined significance (MGUS) have increased rates of bone resorption, osteopenia, osteoporosis, and risk of fractures. This study was undertaken to determine the efficacy and safety of zoledronic acid for patients with MGUS and enhanced bone loss.

EXPERIMENTAL DESIGN

In this phase II open-label study, 54 patients with MGUS and osteopenia or osteoporosis were administered zoledronic acid 4 mg i.v. at 0, 6, and 12 months. The primary efficacy end point was bone mineral density, assessed using a dual-energy X-ray absorptiometry scan in the lumbar (L)-spine done at screening and at 13 months (1 month after the final zoledronic acid infusion).

RESULTS

At study end for all patients (N = 54), L-spine T-scores improved by a median of +0.27 (range, -0.38 to +3.91), corresponding to a median increase in bone mineral density of +15.0% (range, -18.0% to +1,140.0%; P < 0.0001). Hip T-scores improved by a median of +0.10 (range, -2.40 to +2.03), corresponding to a median increase of +6.0% (range, -350.0% to +165.0%). During the study, no new fractures, osteonecrosis of the jaw, or significant renal adverse events were reported.

CONCLUSIONS

Zoledronic acid administered i.v. at a dosage of 4 mg every 6 months for three doses total was well-tolerated and substantially improved bone mineral density for patients with MGUS and bone loss. Zoledronic acid may be effective for the prevention of new fractures in this high-risk population.

A phase I/II study of arsenic trioxide/bortezomib/ascorbic acid combination therapy for the treatment of relapsed or refractory multiple myeloma

PURPOSE

This multicenter, open-label, phase I/II dose escalation study assessed the safety/tolerability and initial efficacy of arsenic trioxide/bortezomib/ascorbic acid (ABC) combination therapy in patients with relapsed/refractory multiple myeloma.

EXPERIMENTAL DESIGN

Enrolled in six cohorts, patients were given arsenic trioxide (0.125 or 0.250 mg/kg), bortezomib (0.7, 1.0, or 1.3 mg/m(2)), and a fixed dose of ascorbic acid (1 g) i.v. on days 1, 4, 8, and 11 of a 21-day cycle for a maximum of eight cycles. The primary end point was safety/tolerability of the ABC regimen.

RESULTS

Twenty-two patients (median age, 63 years) were enrolled, having failed a median of 4 (range, 3-9) prior therapies. One occurrence of grade 4 thrombocytopenia was observed. One patient had asymptomatic arrhythmia and withdrew from the study. Objective responses were observed in 6 (27%) patients, including two partial responses and four minor responses. Median progression-free survival was 5 months (95% confidence interval, 2-9 months), and median overall survival had not been reached. The 12-month progression-free survival and overall survival rates were 34% and 74%, respectively. One (minor response) of six patients receiving the lowest dose of bortezomib (0.7 mg/m(2)) and 5 (2 partial responses and 3 minor responses) of 16 patients receiving the higher doses (1.0 or 1.3 mg/m(2)) responded.

CONCLUSIONS

The ABC regimen was well tolerated by most patients, and it produced preliminary signs of efficacy with an objective response rate of 27% in this heavily pretreated study population. These findings warrant further clinical evaluation of the ABC combination for treatment of relapsed/refractory multiple myeloma.

Efficacy and safety of melphalan, arsenic trioxide and ascorbic acid combination therapy in patients with relapsed or refractory multiple myeloma: a prospective, multicentre, phase II, single-arm study

We assessed the safety and efficacy of melphalan, arsenic trioxide (ATO) and ascorbic acid (AA) (MAC) combination therapy for patients with multiple myeloma (MM) who failed more than two different prior regimens. Patients received melphalan (0.1 mg/kg p.o.), ATO (0.25 mg/kg i.v.) and AA (1 g i.v) on days 1-4 of week 1, ATO and AA twice weekly during weeks 2-5 and no treatment during week 6 of cycle 1; during cycles 2-6, the schedule remained the same except ATO and AA were given twice weekly in week 1. Objective responses occurred in 31 of 65 (48%) patients, including two complete, 15 partial and 14 minor responses. Median progression-free survival and overall survival were 7 and 19 months respectively. Twenty-two patients had elevated serum creatinine levels (SCr) at baseline, and 18 of 22 (82%) showed decreased SCr levels during treatment. Specific grade 3/4 haematological (3%) or cardiac adverse events occurred infrequently. Frequent grade 3/4 non-haematological adverse events included fever/chills (15%), pain (8%) and fatigue (6%). This steroid-free regimen was effective and well tolerated in this heavily pretreated group. These results indicate that the MAC regimen is a new therapeutic option for patients with relapsed or refractory MM.

Serum pleiotrophin levels are elevated in multiple myeloma patients and correlate with disease status

Pleiotrophin (PTN), a tightly regulated angiogenic and mitogenic heparin-binding protein, is markedly elevated in a variety of aggressive solid tumours. The role of PTN in haematological malignancies, however, has not been previously evaluated. This study demonstrated that PTN serum levels were elevated in multiple myeloma (MM) patients when compared with healthy subjects (P < 0.0001). Serum levels of this protein significantly increased during progression of disease, and decreased during response to anti-MM therapy (P < 0.001). These results suggest that serum PTN may be a new biomarker for monitoring the disease status and therapeutic response of MM patients.

A Phase I, open label, dose ranging trial of intravenous bolus zoledronic acid, a novel bisphosphonate, in cancer patients with metastatic bone disease

BACKGROUND

Bone metastases typically are associated with osteolytic bone destruction, resulting in bone pain, pathologic fractures, spinal cord compression, and hypercalcemia. Bisphosphonates are potent inhibitors of normal and pathologic bone resorption and represent a significant therapeutic improvement in the management of patients with lytic bone metastases. Zoledronic acid is a new-generation, highly potent, nitrogen-containing bisphosphonate that to the authors knowledge is the most potent inhibitor of bone resorption currently in clinical trials. The objectives of the current study were to assess the safety and tolerability of increasing doses of zoledronic acid and to determine its activity with respect to reducing biochemical markers of bone resorption in cancer patients with bone metastases.

METHODS

Forty-four cancer patients with bone metastases or primary bone lesions were enrolled sequentially into 1 of 5 fixed ascending-dose treatment groups. Each patient received a single intravenous bolus injection of 1, 2, 4, 8, or 16 mg of zoledronic acid over 30-60 seconds. Patients were monitored for 8 weeks for the evaluation of clinical findings, adverse events, vital signs, electrocardiograms, markers of bone resorption, and urinary N-acetyl-beta-D-glucosaminidase.

RESULTS

Zoledronic acid was safe and well tolerated at all dose levels tested. Commonly reported adverse events included bone pain, fever, anorexia, constipation, and nausea, which were experienced by a similar proportion of patients in each treatment group. Seven patients reported serious adverse events, none of which appeared to be related to the study drug. Zoledronic acid effectively suppressed biochemical markers of bone resorption, including the highly specific markers N-telopeptide and deoxypyridinoline, for up to 8 weeks in the 2-16-mg dose groups and for a shorter duration in the 1-mg group.

CONCLUSIONS

In the current study, zoledronic acid was safe and well tolerated and demonstrated potent inhibition of bone resorption. The authors believe it may improve the treatment of metastatic bone disease.

C-type natriuretic peptide expression and pulmonary vasodilation in hypoxia-adapted rats

Atrial and brain natriuretic peptides (ANP and BNP, respectively) are potent pulmonary vasodilators that are upregulated in hypoxia-adapted rats and may protect against hypoxic pulmonary hypertension. To test the hypothesis that C-type natriuretic peptide (CNP) also modulates pulmonary vascular responses to hypoxia, we compared the vasodilator effect of CNP with that of ANP on pulmonary arterial rings, thoracic aortic rings, and isolated perfused lungs obtained from normoxic and hypoxia-adapted rats. We also measured CNP and ANP levels in heart, lung, brain, and plasma in normoxic and hypoxia-adapted rats. Steady-state CNP mRNA levels were quantified in the same organs by relative RT-PCR. CNP was a less potent vasodilator than ANP in preconstricted thoracic aortic and pulmonary arterial rings and in isolated lungs from normoxic and hypoxia-adapted rats. Chronic hypoxia increased plasma CNP (15 +/- 2 vs. 6 +/- 1 pg/ml; P < 0.05) and decreased CNP in the right atrium (35 +/- 14 vs. 65 +/- 17 pg/mg protein; P < 0.05) and in the lung (3 +/- 1 vs. 14 +/- 3 pg/mg protein; P < 0.05) but had no effect on CNP in brain or right ventricle. Chronic hypoxia increased ANP levels fivefold in the right ventricle (49 +/- 5 vs. 11 +/- 2 pg/mg protein; P < 0.05) but had no effect on ANP in lung or brain. There was a trend toward decreased ANP levels in the right atrium (2,009 +/- 323 vs. 2,934 +/- 397 pg/mg protein; P = not significant). No differences in CNP transcript levels were observed between the two groups of rats except that the right atrial CNP mRNA levels were lower in hypoxia-adapted rats. We conclude that CNP is a less potent pulmonary vasodilator than ANP in normoxic and hypoxia-adapted rats and that hypoxia raises circulating CNP levels without increasing cardiopulmonary CNP expression. These findings suggest that CNP may be less important than ANP or BNP in protecting against hypoxic pulmonary hypertension in rats.

B-lymphoma induction by reticuloendotheliosis virus: characterization of a mutated chicken syncytial virus provirus involved in c-myc activation

Nondefective reticuloendotheliosis virus induces chicken bursal lymphoma in a manner similar to that of avian leukosis virus. The provirus integrates in the c-myc locus and uses a promoter insertion mechanism to activate c-myc expression. We cloned a provirus involved in c-myc activation from a B lymphoma. Detailed structural characterization of this clone, including sequence determination, revealed proviral insertion at 512 base pairs preceding the second c-myc exon. The provirus has a deletion of 80% of the viral genes but retains two intact long terminal repeats (LTRs). A segment of the viral env sequence is present in an inverted orientation. Elevated expression of c-myc, apparently directed by the 3' LTR, was detected. However, despite the presence of an intact 5' LTR, no viral transcripts were detected. Thus, the internal proviral rearrangement can affect 5' LTR transcription or stability of the message or both. This finding is in consonance with the view that proviral deletion plays an important role in the induction of bursal lymphomas by nonacute retroviruses.

Double cos site vectors: simplified cosmid cloning

A new vector for construction of cosmid libraries is described. Cosmid c2XB contains restriction sites for use in the insertion of foreign DNA and two lambda cos sites separated by a blunt-end restriction site. The presence of two cos sites on a single plasmid eliminates the need to prepare two separate cosmid arms, and the internal blunt-end restriction site prevents cosmid concatemerization. Thus, a double restriction-enzyme digestion is sufficient to prepare the vector for subsequent ligation with DNA fragments which are dephosphorylated to prevent their self-ligation. The use of this vector system allows efficient cosmid cloning (1 X 10(5) colonies per micrograms insert DNA) and eliminates background due to vector self-ligation. Furthermore, the procedure is so rapid as to eliminate the need to amplify cosmid libraries for storage and reuse. Also described is a cosmid vector for use in construction of cosmid libraries which are to be introduced into cultured eukaryotic cells. This vector contains the Herpes simplex virus thymidine kinase (HSV tk) gene as a selectable marker and a retroviral long terminal repeat (LTR) region as an enhancer sequence.