A Phase I Trial of High-Dose Lenalidomide and Melphalan as Conditioning for Autologous Stem Cell Transplantation in Relapsed or Refractory Multiple Myeloma

Autologous stem cell transplantation (ASCT) conditioned with high-dose chemotherapy has long been established as the standard of care for eligible patients with newly diagnosed multiple myeloma. Despite recent therapeutic advances, high-dose melphalan (HDM) remains the chemotherapy regimen of choice in this setting. Lenalidomide (LEN) in combination with low-dose dexamethasone is recognized as a standard of care for patients with relapsed or refractory multiple myeloma (RRMM), and there is growing support for the administration of LEN as maintenance therapy post-ASCT. In view of the above, the present phase I clinical trial was designed to evaluate the safety and tolerability of high-dose LEN (HDLEN) in patients with RRMM, and to determine the maximum tolerated dose of HDLEN when added to HDM before ASCT. Despite administering HDLEN at doses of up to 350 mg/day, the maximum tolerated dose could not be determined, owing to an insufficient number of dose-limiting toxicities in the 21 patients enrolled in the trial. Conditioning with HDLEN plus HDM was associated with a favorable tolerability profile. Adverse events following ASCT were as expected with HDM. Median progression-free and overall survival were 10 months and 22 months, respectively, in this population of heavily pretreated patients. Our findings suggest that HDLEN in combination with HDM may offer significant potential as a conditioning regimen before ASCT in patients with RRMM. These preliminary findings are now being evaluated further in an ongoing phase II clinical trial.

Thalidomide, clarithromycin, lenalidomide and dexamethasone therapy in newly diagnosed, symptomatic multiple myeloma

We studied T-BiRD (thalidomide [Thalomid(®)], clarithromycin [Biaxin(®)], lenalidomide [Revlimid(®)] and dexamethasone) in symptomatic, newly diagnosed multiple myeloma. In 28-day cycles, patients received dexamethasone 40 mg/day on days 1, 8, 15, 22, clarithromycin 500 mg twice daily on days 1-28; lenalidomide 25 mg/day on days 1-21; and thalidomide 100 mg/day (50 mg/day on days 1-7 of cycle 1 only) on days 1-28. Twenty-six patients received a median of 6 cycles (range 0-41). Overall response rate (ORR) was 80% for the group and 100% in 11 patients who underwent autologous stem cell transplantation as part of first-line therapy. The 4-year overall survival rate was 74.9%, and the median progression-free survival was 35.6 months. Eight patients discontinued due to regimen toxicity. Grade 3 non hematologic toxicity affected 12 patients (46.2%). T-BiRD is a highly active regimen with potential toxicity limitations. ClinicalTrials.gov identifier: NCT00538733.

Overcoming the response plateau in multiple myeloma: a novel bortezomib-based strategy for secondary induction and high-yield CD34+ stem cell mobilization

PURPOSE

This phase II study evaluated bortezomib-based secondary induction and stem cell mobilization in 38 transplant-eligible patients with myeloma who had an incomplete and stalled response to, or had relapsed after, previous immunomodulatory drug-based induction.

EXPERIMENTAL DESIGN

Patients received up to six 21-day cycles of bortezomib plus dexamethasone, with added liposomal doxorubicin for patients not achieving partial response or better by cycle 2 or very good partial response or better (≥VGPR) by cycle 4 (DoVeD), followed by bortezomib, high-dose cyclophosphamide, and filgrastim mobilization. Gene expression/signaling pathway analyses were conducted in purified CD34+ cells after bortezomib-based mobilization and compared against patients who received only filgrastim ± cyclophosphamide. Plasma samples were similarly analyzed for quantification of associated protein markers.

RESULTS

The response rate to DoVeD relative to the pre-DoVeD baseline was 61%, including 39% ≥ VGPR. Deeper responses were achieved in 10 of 27 patients who received bortezomib-based mobilization; postmobilization response rate was 96%, including 48% ≥ VGPR, relative to the pre-DoVeD baseline. Median CD34+ cell yield was 23.2 × 10(6) cells/kg (median of 1 apheresis session). After a median follow-up of 46.6 months, median progression-free survival was 47.1 months from DoVeD initiation; 5-year overall survival rate was 76.4%. Grade ≥ 3 adverse events included thrombocytopenia (13%), hand-foot syndrome (11%), peripheral neuropathy (8%), and neutropenia (5%). Bortezomib-based mobilization was associated with modulated expression of genes involved in stem cell migration.

CONCLUSION

Bortezomib-based secondary induction and mobilization could represent an alternative strategy for elimination of tumor burden in immunomodulatory drug-resistant patients that does not impact stem cell yield.

Clarithromycin, pomalidomide, and dexamethasone (ClaPD) in relapsed or refractory multiple myeloma

8036

Background: Clarithromycin has been shown to enhance anti-myeloma activity of lenalidomide+dexamethasone in the upfront treatment of multiple myeloma (MM). Pomalidomide is an immunomodulatory agent effective in relapsed/refractory MM (RRMM). We hypothesized that clarithromycin may similarly enhance pomalidomide + dexamethasone in RRMM. We now report updated results from a phase 2 trial of ClaPD in RRMM. Methods: 73 patients with RRMM were enrolled in a single-institution phase 2 study of ClaPD. All subjects had ≥ 3 prior lines of therapy, one of which must have included lenalidomide. ClaPD is clarithromycin 500mg twice daily; dexamethasone 40mg weekly; and pomalidomide 4mg for days 1-21 of a 28-day cycle. All patients had VTE prophylaxis with aspirin. Monthly disease response evaluation included immunoelectrophoresis and free light chain analysis; bone marrow biopsy with skeletal imaging was used to confirm MM responses. Treatment continued as tolerated until disease progression. Results: The 66 patients who completed ≥ 1 cycle of ClaPD are reported. Median number of cycles was 6 (range 1-17). Responses were progressive disease: 10%, stable disease: 21%, minimal response: 12%, partial response: 33%, very good partial response: 18%, stringent complete remission: 5%, for an overall response rate (ORR) of 56% and ≥VGPR rate of 23%. Median time to PR was 1.25 cycles (range 1-8). Median PFS was 5 months. Response and PFS were not different in patients refractory to lenalidomide (85%), bortezomib (82%), or double-refractory patients (76%). After a median follow up of 12 months,28 pts (42%) remain on study without progression and 56pts (85%) are alive. Two pts withdrew due to toxicity (1 Grade 3 fatigue, 1 Grade 4 muscular weakness). One patient withdrew consent. Conclusions: ClaPD is highly effective for heavily pre-treated RRMM, particularly in lenalidomide-refractory disesase and compares favorably to previously published Phase 2 data of Pom/Dex (ORR 56% vs 40% - Lacy et. al JCO 2009) without excess toxicity. Response to ClaPD is rapid, well tolerated, and sustained over 7 months in most subjects. These data support the clinical efficacy of pomalidomide based regimens in RRMM.

Prophylactic low-dose aspirin is effective antithrombotic therapy for combination treatments of thalidomide or lenalidomide in myeloma

Multiple myeloma (MM) patients have a propensity for thromboembolic events (TE), and treatment with thalidomide/dexamethasone or lenalidomide/dexamethasone increases this risk. This report describes the use of low-dose aspirin (81 mg) as primary thromboprophylaxis in three series of MM patients receiving thalidomide or lenalidomide with other drugs. In the first regimen (clarithromycin, thalidomide, dexamethasone), initiation of low-dose aspirin negated the occurrence of any further TE. In a second study, prophylactic aspirin given with thalidomide/dexamethasone resulted in a rate of TE similar to that seen with dexamethasone alone (without aspirin). A third study (n = 72) evaluated thrombosis rates with aspirin and a lenalidomide-containing regimen (clarithromycin, lenalidomide, dexamethasone). Of nine occurrences of thromboembolism, five were associated with aspirin interruption or poor compliance. Low-dose aspirin appears to reduce the incidence of thrombosis with these regimens. Routine use of aspirin as antithrombotic prophylaxis in MM patients receiving immunomodulatory drugs with corticosteroids is warranted.

BLT-D (clarithromycin [Biaxin], low-dose thalidomide, and dexamethasone) for the treatment of myeloma and Waldenström's macroglobulinemia

Multiple myeloma remains incurable. Despite the pursuit of various chemotherapeutic approaches, little improvement in outcome has been made in the last 30 years. Thalidomide, dexamethasone, and clarithromycin are oral, nonmyelosuppressive agents, each with reported single agent activity against myeloma. We evaluated a regimen of clarithromycin (Biaxin), low-dose thalidomide and dexamethasone (BLT-D) in patients with previously untreated or treated multiple myeloma or Waldenström's macroglobulinemia. Patients were initially given clarithromycin 500 mg twice daily, thalidomide 50-200 mg daily, and dexamethasone 40 mg weekly until disease progression. Minimum response was defined as > 50% reduction in monoclonal immunoglobulin or light chain levels in serum or urine. Response, toxicity, and survival were determined on an evaluable and/or intent-to-treat basis. Of the 50 patients available for analysis, 92% remain alive and 64% remain on treatment with a median and mean duration of treatment of 7 and 8 months, respectively. Overall, 93% of evaluable patients responded to BLT-D, including 13% complete remissions, 40% near complete responses, 13% major responses, and 27% partial responses. Minimal drug resistance was initially encountered. Neurotoxicity, although usually mild to moderate, was the primary reason for treatment discontinuation. Only four patients died, including three sudden deaths in patients with severe cardiopulmonary disease. It appears that BLT-D is a highly effective, nonmyelosuppressive regimen for myeloma. Caution should be exercised when using thalidomide, alone or in combination, in patients with a preexisting tendency to thromboses, severe cardiopulmonary disease, or neurologic dysfunction.

Rapid diagnosis of cytomegalovirus pneumonia in marrow transplant recipients by bronchoalveolar lavage using the polymerase chain reaction, virus culture, and the direct immunostaining of alveolar cells

The objective was to compare the use of the polymerase chain reaction (PCR), virus culture, and immunostaining of alveolar cells used alone and in combination as diagnostic methods for the rapid diagnosis of cytomegalovirus (CMV) pneumonia in marrow transplant recipients. Seventy-five marrow transplant recipients with clinical and radiological evidence of pneumonitis were used as subjects. Bronchoalveolar lavage was performed on all patients to obtain material for conventional and/or rapid CMV culture, immunostaining of alveolar cells with monoclonal antibodies (MoAbs), and amplification of CMV-DNA by PCR. Assay results were then prospectively correlated with clinical outcome. Seven of the 75 patients (9.3%) had CMV pneumonitis and 6 patients (8%) had CMV infection without pneumonia. PCR is the most sensitive assay for the detection of CMV in bronchoalveolar lavage fluid. For the diagnosis of CMV pneumonitis, the sensitivity of alveolar cell immunostaining and PCR were both 100%. The sensitivity of virus culture was 85.7%. The positive predictive value for each test, used alone, for the identification of CMV pneumonitis was low. However, when the result of the PCR assay was assessed in combination with CMV immunostaining of alveolar cells, the sensitivity, specificity, positive, and negative predictive value of this strategy was 100%. The concomitant use of PCR and the rapid immunostaining of alveolar cells for CMV has facilitated the development of a sensitive and specific diagnostic algorithm for the detection and early treatment of CMV pneumonitis in transplant recipients.

Cytotoxic and proliferative T-cell clones with antidonor reactivity from a patient transplanted for severe combined immunodeficiency disease

Patients who have become split lymphoid chimeras (T cells of donor origin, B cells and monocytes of host origin) following transplantation of HLA-haploidentical marrow for the treatment of severe combined immunodeficiency disease provide a unique model for the study of tolerance. One such patient, UPN 345, was transplanted with maternal marrow and was found to have antidonor proliferative reactivity without detectable donor-directed cytotoxicity when tested at 18, 23, and 66 mos following bone marrow transplantation. In bulk culture, the proliferation to donor cells could be blocked by monoclonal antibodies to HLA-DR and -DQ. Nine clones with antidonor reactivity were established by limiting dilution techniques from a mixed lymphocyte culture between engrafted T cells and irradiated donor E rosette-negative cells. All of the clones were of maternal donor origin, and all were CD3+CD4+CD8-. The clones were tested for proliferative and cytotoxic activity toward donor, host, and paternal B-lymphoblastoid cell lines (B-LCL). Six clones proliferated strongly to maternal B-LCL but not to host B-LCL. Six clones were found to exclusively lyse maternal B-LCL. Four of the clones had both antidonor cytotoxic and antidonor proliferative reactivity. Monoclonal antibody blocking studies were performed on five of the six clones with cytotoxic activity. The antidonor cytotoxicity was not inhibited by monoclonal antibodies to class I determinants; however, three clones were inhibited in the presence of monoclonal antibody to DR, one clone was inhibited by anti-DQ monoclonal antibody, and one clone was inhibited by anti-DP monoclonal antibody. The cytotoxicity of all five clones was inhibited by monoclonal antibody to CD4. These data indicate that antidonor reactivity may also include a cytotoxic component which is not apparent in bulk cultures and which, based on our limiting dilution studies, is probably controlled by regulatory cells. Both the antidonor cytotoxicity and the antidonor proliferation appear to be directed primarily toward donor HLA class II antigens that are not shared with the patient.

NK and LAK activities from human marrow progenitors. I. The effects of interleukin-2 and interleukin-1

We have investigated the role of interleukin-2 (IL2) as a differentiation factor for human marrow-derived NK cell progenitors and have assessed the effects of interleukin-1 (IL1) on this activity. The effects of these cytokines on early NK cell precursors was determined by testing marrow which had been depleted of mature cells and of CD2+ cells by treatment with soybean agglutinin and sheep erythrocytes (SBA-E-BM). The cytolytic activities of the SBA-E-BM were tested in 51Cr release assays following 7-8 days of liquid culture. K562 targets were used to assess NK activity and NK-resistant Daudi targets were used to measure lymphokine-activated killer (LAK) cell activity. Neither NK nor LAK activity were measurable in marrow incubated in medium without cytokines, or in medium containing IL1 alone. In contrast, culture in medium containing IL2 resulted in a dose-dependent development of lytic activity. NK and LAK activities could be differentiated by the percentage of cultures in which the activity developed, the dose of IL2 required, the time kinetics of induction, and the effect of depletion of residual cells with NK phenotype prior to culture. The most lytically active effectors of both activities, however, were CD56+. Immunofluorescence analyses before and after culture with IL2 revealed that Leu19+ (CD56) cells increased from less than 2% to as much as 17% of the total marrow cells and showed the appearance of a population of CD56+CD16- cells. The addition of IL1 to the marrow cultures increased NK activity when suboptimal amounts of IL2 were used (less than or equal to 100 U/ml), but did not increase LAK activity at any concentration of IL2. A higher number of NK cells, as well as MY7+(CD13+) myeloid cells were recovered from cultures containing IL1 plus IL2, indicating that NK cells as well as myeloid cells had a growth advantage in the presence of IL1. IL2 receptor (CD25) expression was low in all cultures but was consistently higher in cultures containing IL1 and IL2, however, CD25 was not coexpressed on NK cells. These studies indicate that early NK cell precursors can grow and differentiate in response to IL2 and that NK and LAK lytic activities may be acquired at different developmental stages. IL1 may serve to promote the responsiveness of NK cell progenitors to low concentration of IL2 by a mechanism which may not require expression of CD25.

Natural killer and lymphokine-activated killer cell activities from human marrow precursors. II. The effects of IL-3 and IL-4

Both IL-3 and IL-4 have multi-CSF activity on early marrow progenitors. We have examined the effect of IL-3 and IL-4 on the differentiation of NK cells from their marrow-derived precursors and have further examined the interactions of these cytokines with IL-2 and IL-1. We tested marrow which had been depleted of mature cells and of E rosette-positive cells (including NK cells) by treatment with soybean lectin and SRBC (SBA-E-BM). The cytolytic activities of the SBA-E-BM samples were tested in 51Cr-release assays after 7 days of liquid culture. K562 targets were used as a measure of NK activity and NK-resistant Daudi targets were used to measure lymphokine-activated killer (LAK) cell activity. Neither NK nor LAK activity was detectable in marrow cultured in medium without cytokines, or in medium containing IL-3, or IL-4 alone. Both of these cytokines were shown to be inhibitory to the IL-2-induced generation of NK and LAK activity from SBA-E-BM at concentrations as low as 1 U/ml. The inhibitory activity of both IL-3 and IL-4 was found to occur early in the marrow cultures, with little or no inhibitory effects seen if added 48 h after IL-2. IL-3 appeared to be specifically inhibitory to NK cell precursors since addition of IL-3 to cultures of PBMC did not inhibit IL-2-induced lytic activities. In contrast, IL-4 was equally inhibitory to the activation of marrow and peripheral blood NK cells by IL-2. Mixing experiments demonstrated that the reduced lytic activity in IL-3 or IL-4 containing marrow cultures were not due to suppression of the NK effectors, nor could marrow cultured in IL-3 or IL-4 serve as targets for IL-2-activated NK cells. Phenotype analysis of the lymphoid cells in marrow cultures containing IL-2 combined with IL-3 or IL-4 revealed fewer cells expressing Leu-11 (CD16), or Leu-19 (CD56) and fewer CD16, CD56 coexpressing cells compared with marrow cultured in medium containing IL-2 alone. The inhibitory activity of IL-4, but not IL-3, could be partially reversed if IL-1 was added to the cultures, suggesting that IL-1 and IL-4 have opposing activities on NK cells responsiveness to IL-2. These interactions between cytokines might be important in the regulation of NK cell differentiation and on the functional activity of mature NK cells.

Natural killer and lymphokine-activated killer cell activities from human marrow precursors. II. The effects of IL-3 and IL-4

Both IL-3 and IL-4 have multi-CSF activity on early marrow progenitors. We have examined the effect of IL-3 and IL-4 on the differentiation of NK cells from their marrow-derived precursors and have further examined the interactions of these cytokines with IL-2 and IL-1. We tested marrow which had been depleted of mature cells and of E rosette-positive cells (including NK cells) by treatment with soybean lectin and SRBC (SBA-E-BM). The cytolytic activities of the SBA-E-BM samples were tested in 51Cr-release assays after 7 days of liquid culture. K562 targets were used as a measure of NK activity and NK-resistant Daudi targets were used to measure lymphokine-activated killer (LAK) cell activity. Neither NK nor LAK activity was detectable in marrow cultured in medium without cytokines, or in medium containing IL-3, or IL-4 alone. Both of these cytokines were shown to be inhibitory to the IL-2-induced generation of NK and LAK activity from SBA-E-BM at concentrations as low as 1 U/ml. The inhibitory activity of both IL-3 and IL-4 was found to occur early in the marrow cultures, with little or no inhibitory effects seen if added 48 h after IL-2. IL-3 appeared to be specifically inhibitory to NK cell precursors since addition of IL-3 to cultures of PBMC did not inhibit IL-2-induced lytic activities. In contrast, IL-4 was equally inhibitory to the activation of marrow and peripheral blood NK cells by IL-2. Mixing experiments demonstrated that the reduced lytic activity in IL-3 or IL-4 containing marrow cultures were not due to suppression of the NK effectors, nor could marrow cultured in IL-3 or IL-4 serve as targets for IL-2-activated NK cells. Phenotype analysis of the lymphoid cells in marrow cultures containing IL-2 combined with IL-3 or IL-4 revealed fewer cells expressing Leu-11 (CD16), or Leu-19 (CD56) and fewer CD16, CD56 coexpressing cells compared with marrow cultured in medium containing IL-2 alone. The inhibitory activity of IL-4, but not IL-3, could be partially reversed if IL-1 was added to the cultures, suggesting that IL-1 and IL-4 have opposing activities on NK cells responsiveness to IL-2. These interactions between cytokines might be important in the regulation of NK cell differentiation and on the functional activity of mature NK cells.

Immune reconstitution following bone marrow transplantation: comparison of recipients of T-cell depleted marrow with recipients of conventional marrow grafts

The reconstitution of hematopoietic cells and in vitro assays of immunologic function have been followed in leukemic patients after conventional bone marrow transplantation (BMT) (N = 34) and T-cell depleted BMT (N = 52) from human leukocyte antigen (HLA)-identical sibling donors. No effects of the T-cell depletion could be seen on the recovery of myeloid or lymphoid cells as measured by the day to engraftment or by the absolute number of cells through day 100. Normal numbers of lytically active natural killer cells returned the earliest and were rapidly followed in both groups of patients by the appearance of circulating B cells and normalization of the responses to B-cell mitogens. However, the recovery of normal T-cell proliferative responses were more delayed in recipients of T-cell depleted grafts. Significant quantitative differences were seen only during the first 3 months after transplantation. Neither the number of CD3+ T cells nor the ratio of CD4:CD8 positive cells differed markedly between the two transplant groups. Mitogen-induced immunoglobulin production by peripheral blood lymphocytes (PBL) from patients following T-cell depleted BMT was quantitatively less than that of conventional marrow recipients through the first year, with low normal IgM production reached by 4 to 6 months in both groups. IgG production reached low normal 7 to 9 months after conventional BMT but did not remain at this level until 1 year following either type of transplant. Assessment of the incidence of infections from the day the absolute neutrophil count reached 500 until day 180 after transplant revealed no significant differences between the two groups; indeed, the overall nonleukemic mortality was higher in the recipients of conventional bone marrow. Thus, in our series, the removal of mature cells from the marrow graft did not affect the rate or degree of recovery of myeloid and lymphoid cells but did affect the regeneration of in vitro T-cell dependent functions. We noted early quantitative differences and a delay in the normalization of the T-cell functions measured rather than prolonged absolute deficiencies. The in vitro deficiencies did not result in significant clinically apparent differences between the two groups.