TP53, SF3B1, and NOTCH1 mutations and outcome of allotransplantation for chronic lymphocytic leukemia: six-year follow-up of the GCLLSG CLL3X trial

Blood ◽  
2013 ◽  
Vol 121 (16) ◽  
pp. 3284-3288 ◽  
Author(s):  
Peter Dreger ◽  
Andrea Schnaiter ◽  
Thorsten Zenz ◽  
Sebastian Böttcher ◽  
Marianna Rossi ◽  
...  
Keyword(s):  
Chronic Lymphocytic Leukemia ◽  
Disease Control ◽  
Residual Disease ◽  
Lymphocytic Leukemia ◽  
Key Points ◽  
Tumor Clone ◽  
Minimal Residual ◽  
Notch1 Mutations

Key Points This trial update shows that allotransplantation can provide long-term minimal residual disease–negative disease control in poor-risk chronic lymphocytic leukemia. Six-year survival is close to 60% and is independent of the presence of TP53, SF3B1, and NOTCH1 mutations in the tumor clone.

scholarly journals Serial Minimal Residual Disease Evaluation in Patients with Chronic Lymphocytic Leukemia Under Long-Term Venetoclax Treatment

Blood ◽  
2018 ◽  
Vol 132 (Supplement 1) ◽  
pp. 1876-1876
Author(s):  
Thomas Lew ◽  
Mary Ann Anderson ◽  
Constantine S. Tam ◽  
Sasanka Handunnetti ◽  
Dennis Carney ◽  
...  
Keyword(s):  
Chronic Lymphocytic Leukemia ◽  
Board Of Directors ◽  
Median Time ◽  
Research Funding ◽  
Residual Disease ◽  
Lymphocytic Leukemia ◽  
Advisory Committees ◽  
Minimal Residual

Abstract Background The selective BCL2 inhibitor venetoclax (Ven) achieves an overall response rate of approximately 75-80% as a single agent in relapsed and refractory chronic lymphocytic leukemia/small lymphocytic lymphoma (RR-CLL/SLL)1. At one year ~75% of patients (pts) are progression-free at the approved monotherapy dose of 400 mg/day1,2 and Ven is the only novel agent with a significant rate of minimal residual disease (MRD) negativity (MRD-neg)3. The temporal pattern of MRD levels and systematic long term follow up of pts stratified by their MRD status on Ven have not been reported. We report the long term outcomes according to MRD status for 59 pts with RR-CLL/SLL who attained objective disease response to Ven, and the temporal patterns of change in MRD. Methods We reviewed the clinical outcomes to July 2018 of 67 pts with RR-CLL/SLL enrolled since June 2011 on early phase clinical studies of Ven at our two hospitals. Analysis was restricted to the 59 pts who achieved a partial response or complete response by iwCLL criteria. Pts initially received 150-1200mg Ven/day (45 ≥400mg/day) on one of three ongoing trials: Phase 1 Ven monotherapy (NCT01328626) (n=36), Phase 1b Ven plus rituximab (NCT01682616) (n=14), or Phase 2 Ven monotherapy in del(17p) CLL/SLL (NCT01889186) (n=9). For this analysis MRD-negativity was defined as <1 cell in 10-4 leukocytes by ERIC criteria, or no cells with a CLL phenotype when <400,000 cells were analyzed in an assay with a minimum sensitivity of 0.1%. Of those pts reported as MRD-neg this was confirmed at a level of 10-4 in 71%4. Unless otherwise specified, MRD-neg refers to status in the bone marrow (BM) and pts who were not tested were considered to be MRD-pos (n=2 pts). Landmark analyses of time to progression (TTP) by MRD status used the median time to achievement of MRD-neg. Fisher exact test was used to assess the association of clinical, biological and treatment variables with achievement of MRD-neg. TTP and time to MRD-neg were estimated using the method of Kaplan-Meier, and comparisons among groups used the log-rank (Mantel-Cox) test. Results Of the 59 pts who achieved an objective response to Ven, 21 (36%) achieved MRD-neg in the BM and 26 (44%) in the PB. Of the 38 pts who did not achieve BM MRD-neg, 36 (95%) had at least one BM assessment on treatment; the two remaining pts did not clear MRD in the PB. The strongest positive predictor for the achievement of BM MRD-neg was treatment with Ven plus rituximab (9 of 14 [64%]) achieved vs 13 of 45 [27%] on Ven monotherapy (p=0.02)). Complex karyotype was a negative predictor in pts receiving ≥400mg/day. TP53 aberrant state (mutation and/or del(17p)), bulky adenopathy >5cm and fludarabine-refractoriness were not significantly associated with achievement of MRD-neg, irrespective of dose (table 1). The median time to MRD-neg was 8.2 (range 2 - 46) mths for BM (fig 1A) and 5 (range <1 - 50) mths for PB, with 22/26 (85%) pts who achieved PB MRD-neg doing so within 12 mths of starting Ven. 25/26 had a contemporaneous or subsequent BM aspirate and 20 (80%) achieved BM MRD-neg after a median of 3 (<1 - 17) further mths. After a median follow up of 25 (range 2 - 55) mths since attainment of BM MRD-neg, 8/21 (38%) pts have developed confirmed re-emergence of BM MRD, and a further 2 pts have re-developed PB MRD-pos. Median time to reemergence of BM MRD has not been reached (59% BM MRD relapse free at 2 years post attainment). In a landmark analysis from median time to BM MRD-neg (8.2 mths), TTP by iwCLL criteria was significantly longer among BM MRD-neg pts (n = 21; median TTP 65 mths [95% CI 47 - undefined]) than BM MRD-pos pts (n = 31; median 22 mths [95% CI 14 - 39]; Hazard Ratio (HR) 0.11; p<0.0001) (figure 1B). Similar patterns held for the equivalent landmark analysis according to PB MRD (HR 0.21; p = 0.0002). Conclusions Venetoclax frequently induces BM MRD-neg, and pts achieving BM MRD-neg have very durable responses. Combined Ven plus rituximab increases the rate of BM MRD-neg. With Ven therapy, PB MRD status appears to be a reasonable surrogate for BM MRD status, but further validation is required. Achievement of BM MRD-neg should be the aim of therapy with Ven and Ven-based combination approaches may be the most effective way to achieve this.Roberts; N Engl J Med; 2016;374:311-22.Stilgenbauer; Lancet Oncol; 2016;17:768-78.Seymour; Lancet Oncol; 2017;18:230-40.Rawstron; Leukemia; 2016;30:929-36. Disclosures Lew: Walter and Eliza Hall: Employment, Patents & Royalties. Anderson:Genentech: Research Funding; AbbVie, Inc: Research Funding; Walter and Eliza Hall: Employment, Patents & Royalties. Tam:Janssen: Honoraria, Research Funding; AbbVie: Honoraria, Research Funding; Beigene: Honoraria, Other: Travel funding; Beigene: Honoraria, Other: Travel funding; Pharmacyclics: Honoraria, Travel funding; Gilead: Honoraria; Pharmacyclics: Honoraria; Roche: Honoraria; AbbVie: Honoraria, Research Funding; Gilead: Honoraria; Roche: Honoraria. Roberts:AbbVie: Research Funding; Walter and Eliza Hall: Employment, Patents & Royalties: Employee of Walter and Eliza Hall Institute of Medical Research which receives milestone and royalty payments related to venetoclax; Genentech: Research Funding; Janssen: Research Funding. Seymour:Celgene: Consultancy; AbbVie: Consultancy, Honoraria, Research Funding; F. Hoffmann-La Roche Ltd: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Genentech Inc: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Janssen: Honoraria, Research Funding.

Eradication of Minimal Residual Disease with Alemtuzumab in Chronic Lymphocytic Leukemia Is Associated with Prolonged Survival and Is an Appropriate Theraputic Endpoint for Relapsed CLL.

Blood ◽  
2007 ◽  
Vol 110 (11) ◽  
pp. 3114-3114 ◽  
Author(s):  
Hazem A. Sayala ◽  
Paul Moreton ◽  
Ben Kennedy ◽  
Guy Lucas ◽  
Michael Leach ◽  
...  
Keyword(s):  
Chronic Lymphocytic Leukemia ◽  
Minimal Residual Disease ◽  
Median Survival ◽  
Residual Disease ◽  
Lymphocytic Leukemia ◽  
End Point ◽  
Long Term Follow Up ◽  
Minimal Residual

Abstract Eradication of minimal residual disease (MRD) in chronic lymphocytic leukemia (CLL) is emerging as a desirable therapeutic end point predicting for better outcome. The monoclonal antibody alemtuzumab (Mabcampath) is approved for patients with fludarabine refractory CLL. We previously published 91 patients with relapsed CLL (74 men and 17 women, median age 58 years [range, 32 to 75 years]; 44 fludarabine-refractory) who received a median of 9 weeks (range 1 to 16) of alemtuzumab, 30mg 3x a week after dose escalation, between 1996 and 2003. 84 patients had i.v. alemtuzumab and 7 received it subcutaneously. Responses to alemtuzumab according to NCI-WG criteria were complete remission (CR) in 32 patients (36%), partial remission (PR) in 17 (19%) and no response (NR) in 42 (46%). Detectable CLL to a level of less than one CLL cell in 10,000 leucocytes, assessed by four-color MRD flow cytometry, was eradicated from the blood and marrow in 18 patients (20%). 8 of these 18 patients were fludarabine refractory. We report here the results of long term follow up of this cohort of patients after a median follow up of 77 months (range 5 to 123 months). Median survival was significantly longer in patients achieving MRD negative responses compared with those with detectable CLL at the end of therapy. The median survival for all 18 MRD negative responders has not been reached but was 87 months for the 8 fludarabine-refractory patients achieving MRD negativity. Overall survival for the 18 patients with MRD-negative remissions was 66% at 72 months (see Figure). MRD positive CR patients had a median survival of 56 months, MRD positive PR patients a median survival of 42 months and non-responders a median survival of 14 months. The median treatment-free interval prior to alemtuzumab for the 18 MRD negative patients was 8 months (range 4 to 35). Excluding planned stem cell transplantation performed in CR, the median time to next treatment for the 18 MRD negative patients was 114 months and 72% (13/18) have required no further therapy. Therefore alemtuzumab can induce MRD negative remissions in CLL resulting in a clear survival advantage with 66% of MRD negative patients alive 6 years after alemtuzumab. The markedly increased treatment-free survival and excellent survival for MRD negative patients strongly suggests that achieving an MRD negative remission is an appropriate therapeutic end-point in relapsed CLL. Figure Figure

Eradication of Minimal Residual Disease Using Alemtuzumab Consolidation After High-Dose Methyl-Prednisolone Plus Rituximab (HDMP-R) Is Safe, Effective and Induces Long Term Remission in Chronic Lymphocytic Leukemia

Blood ◽  
2011 ◽  
Vol 118 (21) ◽  
pp. 2866-2866
Author(s):  
Januario E. Castro ◽  
Lina M. Ariza-Serrano ◽  
Juan S. Barajas-Gamboa ◽  
Julio A. Diaz-Perez ◽  
Danelle F. James ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Chronic Lymphocytic Leukemia ◽  
Adverse Events ◽  
Minimal Residual Disease ◽  
Residual Disease ◽  
Lymphocytic Leukemia ◽  
High Dose ◽  
Bulky Disease ◽  
Minimal Residual

Abstract Abstract 2866 Despite advances in the treatment of patients with chronic lymphocytic leukemia (CLL), the disease still remains incurable and eradication of minimal residual disease (MRD) being one of the most challenging goals of treatment. Alemtuzumab (Campath-H1™) has been shown to effectivily eradicate MRD from the bone marrow and induce long-term remissions, however its use is limited to patients without bulky disease. Futhermore, combination of alemtuzumab with chemotherapy has resulted in serious adverse events. In this study, we evaluate the toxicity and efficacy of alemtuzumab as consolidation therapy for CLL patients following induction with high-dose methylprednisolone in combination with rituximab (HDMP-R). Twenty-one patients with evidence of residual disease after treatment with HDMP-R received additional treatment with alemtuzumab. This antibody was administered three times a week for a total of 8 weeks. Patients received antibiotic prophylaxis with trimethoprim-sulfamethoxazole 160/800 mg twice a day × 3 per week, fluconazole 100 mg / day and valganciclovir 900 mg / day. The median age was 60 years (range, 49–73), with Rai stage III-IV in 81% of the patients. Twelve patients (57%) had evidence of unmutated IgVH gene and thirteen (62%) had high level of ZAP-70 expression. Cytogenetic and FISH analysis showed eight patients with deleletion 13q, three patients with trisomy 12, one patient with deletion 11q, five patients with no chromosomal abnomalities and in six patients data was not available. The median number of previous treatments was 1.3 (range, 0–5) and the median time from the end of HDMP-R treatment to initiation of alemtuzumab was 5 months (range, 1–14). After HDMP-R, nine patients (43%) achieved CR and twelve (57%) were in PR; all of them had evidence of residual disease in the bone marrow by 4-color flow cytometry analysis. Eight additional patients achieved CR after consolidation with alemtuzumab for a total of 17 patients (81%) in CR at the end of the study. We found no evidence of MRD (MRDneg) in 12 of those patients (57% of the total and 71% of CR patients). Of the remaining patients, one had PR and three patients had progressive disease for an overall response rate of 86%. The median progression-free survival (PFS) was 63 months (range, 6–84) for all patients. The median PFS in CR MRDneg patients has not been reached at a median follow-up of 46 months (range, 18–84), with 8/12 patients that have not progressed after a time at risk of 3.8 years. CR MRDpos patients have a median PFS of 48 months (range, 6–48). The treatment was well tolerated and there were no deaths attributed to therapy. Adverse events were classified following the NCI common terminology criteria for adverse events (CTCAE) Version 4.0. Two patients (9.5%) developed infections. The first event occurred during the administration of alemtuzumab and required hospitalization of the patient for management of pneumonia galactomannan positive suspicious for invasive aspergillosis (Grade 3), the second event was in a patient with aspegillus sp. infection of the skin that occurred four months after completion of alemtuzumab (Grade 2). Both patients recovered completely. We observed no CMV or other opportunistic infections. Three patients (14%) developed cytopenias; two patients with (Grade 4) thrombocytopenia and three patients with (Grade 4) neutropenia. In conclusion, alemtuzumab consolidation for residual disease after treatment with HDMP-R was well tolerated and effective in patients with CLL. We observed a near two-fold increase in the number of patients that achieved CR and the majority of these (71%) had no evidence of MRD. Moreover, patients with CR MRDneg have an exceptionally long PFS. The low rate of infection and lack of treatment related mortality compares very favorably with previous studies using alemtuzumab consolidation after chemotherapy treatment in which toxicities including treatment related death were found to be prohibitive. These encouraging results provide the rationale for additional studies using this combination therapy. Disclosures: James: Celgene: Research Funding.

scholarly journals Eradication of bone marrow minimal residual disease may prompt early treatment discontinuation in CLL

Blood ◽  
2014 ◽  
Vol 123 (24) ◽  
pp. 3727-3732 ◽  
Author(s):  
Paolo Strati ◽  
Michael J. Keating ◽  
Susan M. O'Brien ◽  
Jan Burger ◽  
Alessandra Ferrajoli ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Chronic Lymphocytic Leukemia ◽  
Minimal Residual Disease ◽  
Early Treatment ◽  
Residual Disease ◽  
Treatment Discontinuation ◽  
Lymphocytic Leukemia ◽  
Prompt Treatment ◽  
Key Points ◽  
Minimal Residual

Key Points MRD eradication is a desirable end point in chronic lymphocytic leukemia. Early MRD eradication may prompt treatment discontinuation.

Bone Marrow May Be More Informative Than Peripheral Blood To Evaluate Minimal Residual Disease During 1st and 2nd Year Follow Up After First-Line Fludarabine, Cyclophosphamide, and Rituximab For Chronic Lymphocytic Leukemia

Blood ◽  
2013 ◽  
Vol 122 (21) ◽  
pp. 1621-1621
Author(s):  
Paolo Strati ◽  
Michael J. Keating ◽  
Susan O'Brien ◽  
Jan A. Burger ◽  
Alessandra Ferrajoli ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Chronic Lymphocytic Leukemia ◽  
Peripheral Blood ◽  
Residual Disease ◽  
Response Assessment ◽  
Lymphocytic Leukemia ◽  
First Line ◽  
Final Response ◽  
Minimal Residual

Abstract Background Minimal Residual Disease (MRD) status at end of first-line chemoimmunotherapy is an independent prognostic factor for patients (pts) with chronic lymphocytic leukemia (CLL). In the CLL8 trial of the German CLL Study Group, peripheral blood (PB) was monitored for MRD during follow up. Because the microenvironment is important for CLL cell growth and survival and typically it is the last site to eliminate residual disease with chemoimmunotherapy, bone marrow (BM) might be a more reliable site to monitor MRD. Methods Two-hundred thirty-seven pts with CLL and an indication for therapy (IWCLL-WG 2008) received first-line fludarabine, cyclophosphamide, and rituximab (FCR) on protocol between 09/2008 and 09/2012. MRD was prospectively assessed in BM and/or PB by flow cytometry using the highly sensitive international standardized approach, 2 months after the last course of treatment (final response assessment) and every 3-6 months thereafter. Kaplan-Meier estimates were compared using the log-rank test. Results Sixty-one percent of pts were male, 21% were >65 years old, 40% had Rai stage III-IV, 41% had beta2-microglobulin (B2M) ≥4 mg/L, 61% had unmutated IGHV, and 21% had FISH analysis positive for deletion 11q and 7% for deletion 17p. Seventy-five percent of pts received ≥3 total courses of FCR. The complete remission (CR) and overall response (OR) rates were 65 and 97%, respectively. BM MRD negativity was achieved in 59% of pts at final response assessment. For monitoring, BM MRD was assessed in 121 pts during the 1st year and in 30 pts during the 2nd year after completion of treatment with FCR; all samples were serial. PB MRD was assessed in 106 pts during the 1st year and in 57 during the 2nd year of follow up; again all samples were serial. BM MRD negativity was observed in 63 (52%) pts during the 1st year of follow up and in 15 (50%) pts during the 2nd year. PB MRD negativity was observed at the same staging times in 81 (76%) and 29 (51%) pts, respectively. Concurrent BM and PB samples were taken during the 1st year in 51 pts, and in 6 pts during the 2nd year of follow up. We evaluated the association between MRD negativity during the 1st and 2nd year of follow-up and progression-free survival (PFS). BM MRD positive status was associated with shorter PFS when assessed during both the 1st and 2nd year of follow up (p<0.001 and p=0.001, respectively; Figure). In contrast, PB MRD positive status did not correlate with PFS for either time (p=0.15 and p=0.79, respectively; Figure). Conclusions After first-line FCR for pts with CLL, positive BM MRD may identify pts at higher risk for progression. Based on this finding, BM may be preferred to assess MRD status and pts with positive BM MRD could be considered for maintenance or consolidation strategies. Additional studies confirming these findings are warranted. Disclosures: No relevant conflicts of interest to declare.

scholarly journals Fixed Duration of Venetoclax-Rituximab in Relapsed/Refractory Chronic Lymphocytic Leukemia Eradicates Minimal Residual Disease and Prolongs Survival: Post-Treatment Follow-Up of the MURANO Phase III Study

2019 ◽  
Vol 37 (4) ◽  
pp. 269-277 ◽  
Author(s):  
Arnon P. Kater ◽  
John F. Seymour ◽  
Peter Hillmen ◽  
Barbara Eichhorst ◽  
Anton W. Langerak ◽  
...  
Keyword(s):  
Chronic Lymphocytic Leukemia ◽  
Disease Progression ◽  
Minimal Residual Disease ◽  
Residual Disease ◽  
Lymphocytic Leukemia ◽  
Fixed Duration ◽  
Low Level ◽  
High Level ◽  
Minimal Residual

Purpose The MURANO study demonstrated significant progression-free survival (PFS) benefit for fixed-duration venetoclax-rituximab compared with bendamustine-rituximab in relapsed/refractory chronic lymphocytic leukemia. With all patients off treatment, we report minimal residual disease (MRD) kinetics and updated outcomes. Methods Patients were randomly assigned to 2 years of venetoclax plus rituximab during the first six cycles, or six cycles of bendamustine-rituximab. Primary end point was PFS. Safety and peripheral blood (PB) MRD status—at cycle 4, 2 to 3 months after end of combination therapy (EOCT), and every 3 to 6 months thereafter—were secondary end points. Results Of 194 patients, 174 (90%) completed the venetoclax-rituximab phase and 130 (67%) completed 2 years of venetoclax. With a median follow-up of 36 months, PFS and overall survival remain superior to bendamustine-rituximab (hazard ratio, 0.16 [95% CI, 0.12 to 0.23]; and hazard ratio, 0.50 [95% CI, 0.30 to 0.85], respectively). Patients who received venetoclax-rituximab achieved a higher rate of PB undetectable MRD (uMRD; less than 10−4) at EOCT (62% v 13%) with superiority sustained through month 24 (end of therapy). Overall, uMRD status at EOCT predicted longer PFS. Among those with detectable MRD, low-level MRD (10−4 to less than 10−2) predicted improved PFS compared with high-level MRD (10−2 or greater). At a median of 9.9 months (range, 1.4 to 22.5 months) after completing fixed-duration venetoclax-rituximab, overall only 12% (16 of 130) of patients developed disease progression (11 high-level MRD, three low-level MRD). At the end of therapy, 70% and 98% of patients with uMRD remained in uMRD and without disease progression, respectively. Conclusion With all patients having finished treatment, continued benefit was observed for venetoclax-rituximab compared with bendamustine-rituximab. uMRD rates were durable and predicted longer PFS, which establishes the impact of PB MRD on the benefit of fixed-duration, venetoclax-containing treatment. Low conversion to detectable MRD and sustained PFS after completion of 2 years of venetoclax-rituximab demonstrate the feasibility of this regimen.

Anti-B4 Blocked Ricin Post Chemotherapy in Patients with Chronic Lymphocytic Leukemia--Long-term Follow-up of a Monoclonal Antibody-based Approach to Residual Disease

2003 ◽  
Vol 44 (10) ◽  
pp. 1719-1725 ◽  
Author(s):  
Apostolia M. Tsimberidou ◽  
Francis J. Giles ◽  
Hagop M. Kantarjian ◽  
Michael J. Keating ◽  
Susan M. O'Brien
Keyword(s):  
Monoclonal Antibody ◽  
Chronic Lymphocytic Leukemia ◽  
Residual Disease ◽  
Lymphocytic Leukemia ◽  
Long Term Follow Up

scholarly journals Minimal Residual Disease Dynamics after Venetoclax-Obinutuzumab Treatment: Extended Off-Treatment Follow-up From the Randomized CLL14 Study

2021 ◽  
Author(s):  
Othman Al-Sawaf ◽  
Can Zhang ◽  
Tong Lu ◽  
Michael Z. Liao ◽  
Anesh Panchal ◽  
...  
Keyword(s):  
Overall Survival ◽  
Minimal Residual Disease ◽  
Residual Disease ◽  
Hazard Ratio ◽  
Lymphocytic Leukemia ◽  
Term Outcome ◽  
Long Term Outcome ◽  
Minimal Residual

PURPOSE The CLL14 study has established one-year fixed-duration treatment of venetoclax and obinutuzumab (Ven-Obi) for patients with previously untreated chronic lymphocytic leukemia. With all patients off treatment for at least three years, we report a detailed analysis of minimal residual disease (MRD) kinetics and long-term outcome of patients treated in the CLL14 study. PATIENTS AND METHODS Patients were randomly assigned to receive six cycles of obinutuzumab with 12 cycles of venetoclax or 12 cycles of chlorambucil (Clb-Obi). Progression-free survival (PFS) was the primary end point. Key secondary end points included rates of undetectable MRD and overall survival. To analyze MRD kinetics, a population-based growth model with nonlinear mixed effects approach was developed. RESULTS Of 432 patients, 216 were assigned to Ven-Obi and 216 to Clb-Obi. Three months after treatment completion, 40% of patients in the Ven-Obi arm (7% in the Clb-Obi arm) had undetectable MRD levels < 10−6 by next-generation sequencing in peripheral blood. Median MRD doubling time was longer after Ven-Obi than Clb-Obi therapy (median 80 v 69 days). At a median follow-up of 52.4 months, a sustained significant PFS improvement was observed in the Ven-Obi arm compared with Clb-Obi (median not reached v 36.4 months; hazard ratio 0.33; 95% CI, 0.25 to 0.45; P < .0001). The estimated 4-year PFS rate was 74.0% in the Ven-Obi and 35.4% in the Clb-Obi arm. No difference in overall survival was observed (hazard ratio 0.85; 95% CI, 0.54 to 1.35; P = .49). No new safety signals occurred. CONCLUSION Appearance of MRD after Ven-Obi is significantly slower than that after Clb-Obi with more effective MRD reduction. These findings translate into a superior long-term efficacy with the majority of Ven-Obi–treated patients remaining in remission.

Quantitation of Minimal Residual Disease in Patients with Chronic Lymphocytic Leukemia Using LNA-Modified Fluorescently Labeled Probes and Real-Time PCR Technology.

Blood ◽  
2006 ◽  
Vol 108 (11) ◽  
pp. 2331-2331
Author(s):  
Sona Pekova ◽  
Ludmila Saudkova ◽  
Lukas Smolej ◽  
Miroslav Prucha ◽  
Tomas Kozak
Keyword(s):  
Chronic Lymphocytic Leukemia ◽  
Tumor Cell ◽  
Real Time ◽  
Real Time Pcr ◽  
Residual Disease ◽  
Lymphocytic Leukemia ◽  
Specific Primers ◽  
Pcr Technology ◽  
Minimal Residual

Abstract Background: Patients with chronic lymphocytic leukemia (CLL) relapse even after aggressive therapies and stem cell transplantation. As the therapeutical goal today is to clear off the tumor cell burden as much as possible, highly sensitive assays for minimal residual disease (MRD) evaluation and monitoring are needed. At present, many patients with not only germline IgVH sequences, but also with hypermutated IgVH genes are being treated, with the need for a sensitive and specific MRD monitoring. The original notion of MRD follow-up in CLL was based on the usage of JH-gene specific TaqMan hybridization probes. At present, due to the vast diversity of B-clonal rearrangements to be detected, the original idea has been challenged and the methodology should be modified. Aims: Since the hypermutation process does not restrict itself to the VH segments only and might afflict the JH segment as well, the molecular tools for the monitoring of CLL clonal rearrangements must be versatile enough to allow for the detection and quantitation of virtually any sequence possible. Moreover, the technique must meet the criteria for high sensitivity and specificity. We present here a novel methodology for MRD monitoring in CLL, based on LNA technology (Locked Nucleic Acids) and quantitative Real-Time PCR. Methods: 59 patients with the diagnosis of CLL were enrolled into our MRD study (22 females, 37 males, median age 59.1 yrs). 33 out of 59 individuals had unmutated IgVH genes (4 females, 29 males), 26 out of 59 patients had mutated IgVH genes (15 females, 11 males). For each patient, clone-specific primers were designed and their clonal VH sequences were molecularly cloned to construct the quantitation standards. In one patient, allelic inclusion has been identified (VH1–8 and VH3–30, both mutated), and for this individual, clone-specific primers and standards have been constructed for both rearrangements. To quantify the individual clonal VH transcripts, LNA-modified fluorescently labeled probes targeted against individual gene segments were employed. For any of 6 (7) IgVH families with unmutated VH genes, family-specific consensus LNA-modified probes were used. For those CLL cases with heavily hypermutated genes, ProbeLibrary™ was employed. For quantitation experiments, ABL was used as the control gene. Results: The LNA-modified probes are distinguished by a very high specificity and sensitivity (reaching to 10−8, in contrast to flow cytometry with its detection limit being 10−4). The LNA-based assays allow for precise monitoring of the residual tumor cell burden in CLL patients, especially during those periods of time, when other, less sensitive techniques fail to trace the malignant clone. Conclusions: LNA-modified probes and Real-Time PCR technology represent a highly versatile, specific and extremely sensitive methodology for the monitoring of MRD in chronic lymphocytic leukemia. We strongly advocate their usage in the molecular follow-up of MRD in the setting of CLL (and possibly other B-cell malignancies with hypermutated VH gene sequences as well).

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