Clinical presentation and outcome of patients with AL amyloidosis requiring salvage therapy

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Background: The diagnosis and upfront management of immunoglobulin light chain (AL) amyloidosis have greatly improved in recent years. However, little is known about the presentation, treatment, and outcome of these patients at first relapse/progression (R/P). Methods: All patients with AL amyloidosis who received salvage therapy for first R/P disease at Moffitt Cancer Center between 2008 and 2020 were included in this retrospective review. Definitions of hematologic and organ R/P were based on 2012 consensus. Overall survival was measured from the time of salvage to last follow up/death. Survival was assessed by Kaplan-Meier with log-rank comparison. Results: Sixty-nine patients were included. The median age at diagnosis was 62 years and 61% were male. Upfront therapy included high dose melphalan with autologous transplant in 36% and bortezomib in 52%. At salvage, 19% had disease refractory to upfront therapy and 40% had not achieved an organ response. The median time from upfront to salvage therapy was 22 months. Salvage regimens included proteasome inhibitors, daratumumab and immunomodulatory drugs in 55%, 13% and 22%, respectively. At least a very good partial response and organ response were achieved in 35% (22/62) and 39% (21/54) with measurable disease. The median overall survival was 60 months. Based on salvage indication, patients were classified into hematologic (n = 29) and organ R/P (n = 40), and the latter showed more frequent lambda-light chain disease (59% vs. 83%, p = 0.028) and low difference of involved-uninvolved free light chain at diagnosis (< 50 mg/L, 8% vs. 44%, p = 0.002). Negative prognostic markers for survival included bone marrow plasma cells ≥20% at diagnosis (median 17 months vs. not reached; p < 0.001) and organ, particularly cardiac R/P (median, 31 months vs. not reached; p = 0.003). Salvage ( p = 0.48) or prior regimens ( p = 0.11) did not impact post-salvage survival. Conclusions: Our study highlights the unmet need of salvage in R/P AL amyloidosis in a real-world setting, given the low rate of deep responses regardless of current salvage options. Patients with bone marrow plasma cells ≥20% at diagnosis and organ R/P at salvage had inferior survival, supporting use of intensive upfront regimens for the former and adjustment of therapy if deep response is not achieved.[Table: see text]

Will adding alkylating agent to bortezomib improve survival of newly diagnosed AL amyloidosis patients?

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Background: The combination of bortezomib (Bort) and alkylating agent (AA) is a frequently used first-line therapy for AL amyloidosis. Kastritis et al. compared melphalan and dexamethasone with or without bortezomib as primary therapy and demonstrated increased hematologic response rate with the bortezomib and melphalan combination. However, the role of AA is unclear. This study aimed to evaluate if adding AA to Bort improved patient outcomes in AL amyloidosis. Methods: We retrospectively reviewed clinical data on 209 patients with systemic AL Amyloidosis at Moffitt Cancer Center between 2008 and 2020. We excluded patients with localized amyloidosis or amyloid other than AL. Patients were divided into two groups based on upfront therapy: A) Bort and B) Bort + AA. All patients also received dexamethasone. The staging was per Mayo 2012. Organ involvement, response, and progression were defined based on the 2005 criteria. Overall survival (OS) was defined as the time from initial diagnosis until death or last contact. Time to next therapy (TTNT) was calculated in patients with the documented hematologic response from the time of initiation of therapy to time of the next therapy/last follow up/death. Results: Of 209 patients, 36% (n=76) received Bort+AA; 30% (n=62) received Bort. No significant difference in clinical characteristics was seen in both groups except for age (which was higher for arm A: median 65 and 62 years, respectively, p=0.043) (table). In addition, Bort+AA became more commonly used as a frontline therapy after 1/1/2014 (p=0.001). Group A and B had similar median OS (69.9 months [95% CI. 44.7-95.2] and 64.4 mo [95% CI 40.5-88.3] respectively, p=0.60). 86% of patients in group B achieved a hematologic response as compared to 74% of patients in group A (p=0.15). Similarly, 47% of patients in group B achieved an organ response as compared to 34% of patients in group A (p=0.22). TTNT was higher in group A than group B (16.9 mo [95% CI, 0-41.5] and 7.8 mo [95% CI, 3.5-12.0], respectively, p=0.08). Conclusions: While Bort+AA is a commonly used regimen for amyloidosis, the addition of AA to Bort did not result in superior OS, TTNT compared to Bort alone in this retrospective study. This finding should be confirmed in prospective studies. Baseline Characteristics. [Table: see text]

Impact of doxycycline on outcomes in AL amyloidosis

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Background: It has been shown in mouse models doxycycline(Doxy) interferes with amyloid fibril formation. Retrospective data suggests the addition of Doxy to standard chemotherapy(chemo) reduces mortality in cardiac amyloidosis. We examined the relationship between Doxy use, treatment, and OS in a cohort of AL Amyloidosis(AL) within an academic center. Methods: AL pts between 2008 and 2020 at Moffitt Cancer Center. For this study we included patients with AL, with all types of organ involvement. We excluded pts with non-AL Amyloidosis and pts with localized amyloidosis were excluded. Data on organ involved, organ response, date of death, treatment were obtained for each pt. OS was defined as time from AL diagnosis to date of death. Univariate comparisons were performed to identify differences in treatment and other prognostic variables between Doxy groups, where appropriate (Table). Results: 209 pts that met inclusion criteria, 13 pts(6%) had cardiac involvement with AL. Of those 13 pts, only 3 pts(23%) received Doxy in addition to standard of care chemo. For this study, we included all types of AL for total 209 pts. Of the 209 pts, 9.5% received Doxy in addition to standard of care chemo and 90.5% pts did not receive Doxy and had chemo alone. Pts who received Doxy had more proteinuria (suggesting more significant renal involvement) but other characteristics were not statistically different including cardiac biomarkers (table). A numerically higher rate of organ response (67% versus 43%) was noted in patients who received Doxy but this didn’t reach statistical significance. Further the OS was numerically higher for Doxy treated pts however again this didn’t meet statistical significance. Conclusions: We noted higher organ responses and overall survival in Doxy treated pts, we could not identify statistical differences in outcomes possibly because of the sample size. Nevertheless, further follow up is warranted and Doxy may be associated with improved outcomes in AL. [Table: see text]

An open-label phase I/II study of cyclophosphamide, bortezomib, pegylated liposomal doxorubicin, and dexamethasone in newly diagnosed myeloma

We conducted a phase 1/2 trial evaluating the combination of cyclophosphamide, bortezomib, pegylated liposomal doxorubicin, and dexamethasone (CVDD) for newly diagnosed multiple myeloma (MM). The primary objective of the phase 1 was to evaluate the safety and tolerability of maximum planned dose (MPD) and the phase 2 was to assess the overall response rate. Patients received 6-8 cycles of CVDD at four dose levels. There were no dose-limiting toxicities. The MPD was cyclophosphamide 750 mg/m(2) IV on day 1, bortezomib 1.3 mg/m(2) IV on days 1, 4, 8, 11, pegylated liposomal doxorubicin 30 mg/m(2) IV on day 4, and dexamethasone 20 mg orally on the day of and after bortezomib (21-d cycle). Forty-nine patients were treated at the MPD of which 22% had high-risk myeloma. The most common grade ≥3 toxicities included myelosuppression, infection, and fatigue. Overall response and complete response rates were 91% and 26% in standard-risk, and 100% and 58% in high-risk cohort, respectively. After a median follow-up of 34 months, the median progression-free survival was 31.3 months. The 2-yr overall survival was 91.1% in the standard-risk and 88.9% in the high-risk cohort, respectively. CVDD regimen was well tolerated and was highly active in newly diagnosed MM.

Pharmacokinetically-targeted BU and fludarabine as conditioning before allogeneic hematopoietic cell transplantation for adults with ALL in first remission

Allogeneic hematopoietic cell transplantation offers improved survival in patients with ALL, but with regimens containing TBI, the nonrelapse mortality is 20-40%. Efforts to lessen transplant toxicities by reducing conditioning regimen intensity have led to increased relapse risk. Therefore, there is a need for less toxic regimens that maintain an anti-leukemia effect. We report here a retrospective review of 65 patients with ALL in first remission receiving grafts from allogeneic donors after fludarabine 40 mg/m(2)/day for 4 days and i.v. BU targeted to a median daily area under the concentration-time curve below 6000 μmoles min/L. At 2 years after transplantation, OS was 65% (95% confidence interval (CI): 52-77%), relapse-free survival was 61% (95% CI: 48-73%), cumulative incidence of relapse was 26% (95% CI: 17-39%) and cumulative incidence of nonrelapse mortality was 14% (95% CI: 8-26%). Age over 35 years, Ph chromosome positivity and minimal residual disease at transplant did not adversely affect outcomes. Pharmacokinetically targeted BU and fludarabine can provide intensive pre-transplant conditioning for adults with ALL in first remission, with promising relapse-free and OS rates.

Outcomes of patients with solitary plasmacytomas (SP) in the era of PET imaging and serum-free light chain (sFLC) testing: A single institution experience

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Background: SP can occur in bone (SPB) or in extramedullary sites (EMP) and generally accounts for ~ 3-5% of plasma cell dyscrasias. Up to 50% of SPB and 15% of EMP will progress to multiple myeloma (MM). We evaluated the utility and prognostic significance of positron emission tomography (PET) imaging and SFLC ratio (sFLCr). Methods: We retrospectively reviewed electronic medical records of patients with SP evaluated at Moffitt Cancer Center between 1990-2012. The diagnosis of SP was per IMWG criteria (BJH 2003, 121:749) (biopsy proven single site, negative skeletal survey, bone marrow biopsy with no more than 10% plasma cells). Initial and post therapy sFLCr as well as PET findings were correlated with progression to symptomatic MM (PFS). Radiation therapy (XRT) was at the discretion of the treating physician. Results: 135 patients were identified and 91 (67%) were males. The median age was 58 years (range 20-82). Consistent with prior reports, the PFS of the entire cohort was 43 months (95% CI 17.8-70). 23 patients had PET prior to progression. All patients had uptake in the primary lesion (except 4 who had resection of the primary). 8 patients had additional PET findings in other bony structure (PET+), and 15 did not (PET-). 2 and 6 of the PET- and PET+ patients progressed (median PFS Not reached (NR) vs. 8.1 months, p=0.021) respectively. Of the 49 patients with available sFLC data, 32 had an abnormal ratio (17 progressed) and 17 patients had a normal ratio (2 progressed). Abnormal baseline sFLCr was associated with progression (median PFS 19 months vs NR, p=0.012). Post XRT, 44 patients had an available sFLCr, of which 23 had an abnormal ratio and 21 a normal ratio. A persistent serum/urine m spike after XRT was associated with progression to MM (median PFS 20.8 months vs NR, p<0.0001). However, the association between Post XRT sFLCr and progression to MM was not statistically significant (median PFS 19 vs 43 months (abnormal vs normal ratio) p=0.2). Conclusions: PET imaging and sFLC are predictors of outcomes in SP and their routine inclusion in the diagnostic work up of patients with SP will result in a stage migration where patients outcomes are improved compared to historical controls.

Evaluation of spot urine protein to creatinine ratio and 24-hour urine protein quantification for proteinuria in patients with plasma cell dyscrasia

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Background: Though cumbersome, a 24-hour urine collection remains crucial for diagnosis and monitoring in plasma cell dyscrasias (PCD). Nephrology guidelines recommend replacement of 24-hour urine collection with spot urine protein/creatinine (Pr/Cr) ratio for proteinuria. Only limited data exist on accuracy of spot urine Pr/Cr ratio in PCD. Methods: From 04/2012 to 01/2013, a total of 67 PCD patients were prospectively enrolled. Oliguria or dialysis were considered ineligible. Spot urine was collected on the day of 24-hour urine collection. Spot urine Pr/Cr ratios were compared to 24-hour urine on (1) total protein and (2) monoclonal protein (M-spike). Results: Fifty-two of 67 patients were evaluable (missing samples in 9; no Pr/Cr ratios in 4; protein below the level of detection in 2). A median age was 66 (range, 36 - 82), 62% were male, and 81% were Caucasian. Primary diagnoses were myeloma (n=47), amyloidosis (n=2), plasmacytoma (n=2), and MGUS (n=1). Comorbidities included hypertension (58%), chronic kidney disease (27%), diabetes (19%), and congestive heart failure (2%). A median serum creatinine was 0.9 mg/dL (range, 0.5 - 5.1). A median spot urine Pr/Cr ratio was 140 mg/g creatinine (range, 32 - 21,447), a median 24-hour urine protein was 130 mg (range, 31 - 15,092: n=49), and a median urine M-spike was 1.9 mg (range, 0 - 8,099). Most spot urine samples were collected in the morning (65%). There were strong correlations between (1) spot urine Pr/Cr ratio and 24-hour total urine protein (Spearman correlation coefficient=0.91, p < 0.0001), and (2) spot urine Pr/Cr ratio and 24-hour urine M-spike (Spearman correlation coefficient=0.73, p < 0.0001). The timing of spot urine sample collection had no significant effect (p = 0.274 by Wilcoxon rank-sum test). Conclusions: Spot urine Pr/Cr ratio strongly correlates with proteinuria measured in 24-hour urine collection and may predict the quantity of urine M-spike in non-oliguric PCD population. Spot urine Pr/Cr ratio may be useful as a monitoring tool for estimation of proteinuria. The study is ongoing and updated result will be provided.

Phase II study of CD4+-guided pentostatin lymphodepletion and pharmacokinetically targeted busulfan as conditioning for hematopoietic cell allografting

One limitation of reduced-intensity preparative regimens is potential for graft failure. We have developed a regimen that targets CD4(+) lymphodepletion to ensure early and durable engraftment. The primary endpoint was achievement of ≥50% CD3(+) donor chimerism by day +28. Forty-two patients (median age, 53 years; range, 29 to 73 years) received pentostatin 4 mg/m(2) i.v. on days -28, -21, and -14 when the CD4(+) cell count was >100 cells/μL and on days -4 and -3 regardless of CD4(+) level. Rituximab 375 mg/m(2) was administered to patients with CD20(+) malignancies on days -21, -14, -7, +1, and +8. Busulfan 200 mg/m(2) i.v. was administered on days -4 and -2 at a dose to target a cumulative AUC dose of 16,000 (±10%) μmol·min/L. Graft-versus-host disease (GVHD) prophylaxis consisted of tacrolimus plus methotrexate in 86% of patients. Donors were matched-related (47%), matched unrelated (43%), or mismatched unrelated (10%). Chronic lymphocytic leukemia (45%) and follicular non-Hodgkin lymphoma (14%) were the most common diagnoses. Disease status at initiation of the preparative regimen was complete remission in 22%, partial response in 55%, and stable/progression in 24%. The median percent CD4(+) cell count decrease from baseline (day -28) was 52% to day -21, 66% to day -14, 62% to day -7, and 91% to day 0. At day +28, all 42 patients (100%) had ≥50% CD3(+) donor chimerism. No patient experienced graft failure. Overall response rate was 82% (complete remisson, 67%). The day +100 cumulative incidence of grade II-IV acute GVHD was 59% (grade III-IV acute GVHD, 19%), and the 2 year cumulative incidence of chronic GVHD was 69% (moderate/severe, 58%). Nonrelapse mortality was 2% at day +100 and 17% at 2 years. Two-year PFS was 55%, and OS was 68%. This regimen ensures durable engraftment, is effective against persistent disease, and results in relatively low mortality from causes other than relapse.

Allogeneic hematopoietic cell transplantation for consolidation of VGPR or CR for newly diagnosed multiple myeloma

Allogeneic hematopoietic cell transplantation (HCT) is a potentially curative approach in patients with multiple myeloma, but its use for consolidation of first remission has not yet been fully explored. Twenty-two myeloma patients with very good partial response (VGPR) or CR received allogeneic peripheral blood grafts as consolidation from HLA-matched donors between 2007 and 2012. Conditioning regimens were fludarabine (30 mg/m(2) i.v. if with bortezomib and 40 mg/m(2) i.v. when without bortezomib, × 4 days) plus melphalan (70 mg/m(2) intravenously × 2 days) with (n=13) or without (n=9) bortezomib (1.3 mg/m(2)). The cumulative incidence of grades II - IV acute GVHD at day 100 was 45% (95% CI: 24-65%) and moderate-to-severe chronic GVHD at 2 years was 46% (95% CI: 19-69%). With a median follow-up of 18 (range, 2-61) months, the 2-year PFS estimate is 74.8% (95% CI: 45-90%), which compares favorably with the 52% (95% CI: 35-66%) after autologous HCT for similar patients (a median follow-up of 30 (range, 9-55) months). We are conducting a phase 2 study to assess the efficacy of allogeneic HCT as post-remission therapy.

Bortezomib salvage followed by a Phase I/II study of bortezomib plus high-dose melphalan and tandem autologous transplantation for patients with primary resistant myeloma

We conducted a Phase 1/2 study of bortezomib administered in combination with high-dose melphalan followed by tandem autologous transplants in patients with primary resistant multiple myeloma. Thirty patients received two cycles of salvage bortezomib followed by stem cell mobilization with granulocyte colony-stimulating factor and harvest. Melphalan 100 mg/m(2) per day on two consecutive days was administered, immediately followed by one dose of bortezomib (dose escalation) and stem cell infusion. The median beta 2-microglobulin was 4·35 mg/l (range: 1·8-11·4); albumin was 37 g/l (range: 3·1-4·9); high-risk karyotypes were noted in 45% of patients. The maximum planned dose of bortezomib at 1·3 mg/m(2) was well tolerated and a formal maximum tolerated dose was not determined. The peak of best overall response (≥partial response) and complete response rates after tandem transplants were 84% and 36%, respectively. With a median follow-up of 48 months, the median progression-free survival was 15 [95% confidence interval (CI): 11-21] months and the median overall survival was 35 (95% CI: 22-43) months. Correlative studies demonstrated decreased expression of BRCA2 (P = 0·0072) and FANCF (P = 0·0458) mRNA following bortezomib treatment. Bortezomib combined with high-dose melphalan is a well-tolerated conditioning with some activity in patients with resistant myeloma.

Clinical outcomes of patients with plasma cell leukemia in the era of novel therapies and hematopoietic stem cell transplantation strategies: a single-institution experience

BACKGROUND

PCL carries a poor prognosis and the optimal management remains unknown.

PATIENTS AND METHODS

To evaluate the outcome of patients with PCL in the era of novel agents and innovative transplantation strategies, we conducted a review of patients with PCL who were treated at our institution from August 2003 to October 2009. Our primary endpoint was to determine overall survival, which was calculated from time of PCL diagnosis to death or last follow-up. Secondary endpoints included response rates and analyses regarding how the novel agents and presence of adverse cytogenetic analyses affected outcomes.

RESULTS

We identified 25 patients with PCL (13 with primary PCL [pPCL], 12 with secondary PCL [sPCL]) from our institution. Eighteen patients received bortezomib-based regimens, 19 received high-dose melphalan followed by autologous hematopoietic stem cell transplantation (HCT), and 6 underwent allogeneic HCT. The median overall survival for all patients was 23.6 months. Bortezomib-treated patients had a median survival of 28.4 months vs. 4.0 months for the non-bortezomib-treated group (P < .001).

CONCLUSIONS

Our analysis suggests that patients with PCL who were treated with bortezomib and/or allogeneic HCT had improved outcomes.

Human immunodeficiency virus (HIV)-negative plasmablastic lymphoma: a single institutional experience and literature review

Plasmablastic lymphoma (PBL) is a rare aggressive B-cell lymphoproliferative disorder. HIV-negative PBL has not been extensively reported. Nine HIV-negative PBL patients evaluated at Moffitt Cancer Center were studied. Eight patients had extranodal diseases. All patients were treated with CHOP or hyper-CVAD. Responses were observed in 8 cases (7 complete, 1 partial responses). Four patients underwent consolidation with autologous hematopoietic stem cell transplant (HSCT) in first complete remission (CR1). At median follow-up of 23.9 months, 7 patients were alive and 5 were disease-free. Aggressive induction chemotherapy and consolidation with autologous HSCT in CR1 might be considered for patients with HIV-negative PBL.

Targeted IV busulfan and fludarabine followed by post-allogeneic hematopoietic cell transplantation rituximab demonstrate encouraging activity in CD20+ lymphoid malignancies without increased risk of infectious complications

We examined pharmacokinetic-targeted IV busulfan (75-170 mg/m(2), with target AUC of 3500-6000 μmol min) and fludarabine (40 mg/m(2)) × 4 days with rituximab (t-IV Bu/Flu + rituximab) 375 mg/m(2) on days +1 and +8 followed by allogeneic hematopoietic cell transplantation in 19 patients (median age 56, range 35-68 years) with CD20+ lymphoid malignancies. Median time to neutrophil and platelet engraftment was 15 and 12 days. The cumulative incidence of grade II-IV acute graft-versus-host disease (GVHD) was 58% (95% confidence interval, CI 39-85%), and chronic GVHD was 50% (95% CI 28-88%). With a median follow up of 7 (range 1-31) months, overall response was observed in 15, and stable or progressive disease in 4. Overall survival at 1 year was 67%. Engraftment, chimerism, and infectious complications did not differ significantly from a contemporaneous non-rituximab containing comparator group. The addition of rituximab 375 mg/m(2) to t-IV Bu/Flu does not appear to adversely affect engraftment, donor chimerism, or increase the risk of infectious complications.

Patterns of use of vascular access devices in patients undergoing hematopoietic stem cell transplantation: results of an international survey

INTRODUCTION

There is limited information regarding of use of vascular access devices (VAD) in patients undergoing hematopoietic stem cell transplantation (HSCT). The frequent use of VAD in HSCT and its potential to cause morbidity requires understanding of the general use of VAD in HSCT.

MATERIALS AND METHODS

A World Wide Web-based 19-item questionnaire was designed to determine the patterns of use of VAD in patients undergoing HSCT. The questionnaire was sent via electronic mail to the directors of HSCT programs throughout the world.

RESULTS

Of the 445 centers surveyed, 163 centers replied for a response rate of 37%. The most commonly used catheter for autologous peripheral blood stem cell (PBSC) harvest is the dual-lumen plasmapheresis/hemodialysis (62%). Of the institutions, 58% utilize the same catheter used for PBSC harvest to provide vascular access support during the transplant. Catheter-related blood stream infection (36%) and withdrawal occlusion (31%) were the most frequently encountered complications of VAD. Of the centers, 65% have established criteria for VAD removal when infection is suspected and 48% when occlusion is suspected.

DISCUSSION

Our study demonstrated that there are similarities in the utilization of VAD but also wide differences in the standard procedures for the insertion and care of VAD in the transplant setting. More comprehensive studies are needed to assess the use of central venous catheters in transplant recipients. Important areas for future research include the impact of VAD utilization on the quality of life of transplant recipients and the final consequences of VAD complications.

Incidence of Clostridium difficile-associated diarrhea before and after autologous peripheral blood stem cell transplantation for lymphoma and multiple myeloma

Diarrhea is a major cause of morbidity and discomfort for patients undergoing high-dose chemotherapy and autologous peripheral blood stem cell transplantation (APBSCT). There are multiple causes of diarrhea in patients undergoing transplantation including antineoplastic chemotherapy, antimicrobials and infection, including Clostridium difficile as the most common pathogen involved. The purpose of this study was to determine the incidence of C. difficile-associated diarrhea (CDAD) 1 week before and 30 days after APBSCT, and to identify risk factors for the development of CDAD including diagnosis. Two hundred and forty-two patients underwent APBSCT for multiple myeloma and lymphoma between October 1996 and October 2001 in two teaching hospitals. Diarrhea was reported in 157 (64.9%) subjects. One hundred and thirty-five out of the 157 subjects were tested for the presence of C. difficile toxin A. These subjects constitute the study group. The incidence of CDAD was 15%. Two thirds of the patients who developed CDAD had multiple myeloma and one third had lymphoma; this difference did not attain statistical significance. The use of cephalosporins (P = 0.03) and the use of intravenous vancomycin (P = 0.02) were the only identified risk factors associated with the development of CDAD. Patients treated with paclitaxel as part of the mobilization regimen had a lower incidence of CDAD than patients who received hematopoietic growth factor only (P = 0.01).

Phase I and Pharmacokinetic Study of Sequences of the Rebeccamycin Analogue NSC 655649 and Cisplatin in Patients with Advanced Solid Tumors

PURPOSE

To evaluate the feasibility of administering NSC 655649, a water-soluble rebeccamycin analogue that inhibits both topoisomerases I and II, in combination with cisplatin (CDDP) in adults with solid malignancies. Major toxicologic and pharmacologic differences between the two sequences of drug administration were also assessed.

EXPERIMENTAL DESIGN

NSC 655649 was administered as a 60-minute i.v. infusion; CDDP was given i.v. before or after NSC 655649 on day 1. Each patient was treated with alternating drug sequences every 3 weeks; doses of each drug were escalated in separate cohorts of new patients. Sequential dose escalation of NSC 655649 or CDDP resulted in three dosage permutations of NSC 655649/CDDP: 440/50, 550/50, and 440/75 mg/m2. After the maximum tolerated dose level was determined, the feasibility of using granulocyte colony-stimulating factor to permit further dose escalation was explored.

RESULTS

Twenty patients were treated with 70 courses of NSC 655649/CDDP. Myelosuppression was the principal toxicity. The incidence of severe neutropenia, often associated with severe thrombocytopenia, was unacceptably high in minimally pretreated patients at the NSC 655649/CDDP dose level of 550/50 mg/m2 without and with granulocyte colony-stimulating factor. Major pharmacokinetic interactions between NSC 655649 and CDDP were not apparent. No relevant sequence-dependent differences in toxicity or pharmacokinetic variables occurred. Three patients had partial responses.

CONCLUSIONS

NSC 655649 and CDDP were well tolerated by minimally pretreated subjects at 440 and 50 mg/m2, respectively. Neither pharmacokinetic interactions between the agents nor sequence-dependent toxicologic or pharmacokinetic effects were apparent. The tolerance and preliminary activity observed with this combination suggest that disease-directed evaluations of the regimen are warranted.