ALBERT

Description: Introduction. Chronic myeloid leukemia (CML) patients (pts) treated with imatinib first line achieve complete cytogenetic response (CCyR) in 〉 70% of cases and major molecular response (MMR) in 18-58%. These pts have a life expectancy similar to the general population. However even undetectable BCR-ABL may not equate to eradication of the disease because of the sensitivity of Q-RT-PCR. A new diagnostic method, the digital-PCR (dPCR), able to detect 1 BCR-ABL+ cell out of 107 cells, has been recently developed (Goh HG et al., 2011). dPCR corresponds to a 100 fold increase in sensitivity as compared to Q-RT-PCR. Therefore, dPCR by assessing the presence of minimal residual disease with higher sensitivity, could potentially identify pts in whom CML has been eradicated. Aims. The Imatinib Suspension And Validation (ISAV) study is aimed at validating the capability of dPCR to predict relapses after imatinib discontinuation in CML pts with negative Q-RT-PCR results. Methods. This study involves 15 sites, 10 in Italy and 1 in each of the following countries: Germany, Spain, The Netherlands, Canada and Israel. CML pts (Chronic or Accelerated Phase) under imatinib therapy since more than 2 years and in complete molecular remission (CMR) were eligible for this study. Patients had to be in CMR for at least 18 months (mts), with a minimum of 3 Q-RT-PCR performed at their own sites. After signing the informed consent, blood samples are obtained for dPCR and the pts discontinue imatinib therapy. Standard Q-RT-PCR is performed monthly (mts 1-6) and then bimonthly for 36 mts to assess the maintenance of the molecular remission. The loss of molecular remission is defined as two consecutive positive Q-RT-PCR tests with at least one BCR-ABL/ABL value above 0.1%. Patients losing molecular remission resume imatinib treatment at the same dosage used before interruption. Patients’ quality of life during imatinib discontinuation/resumption is evaluated through the EORTC – C30 Quality of Life questionnaire. Results. The enrolment in ISAV began in November 2011 and ended in July 2013. The study enrolled 112 pts: Italy 69.6%, Germany 21.4%, Canada 5.3%, Spain 2.6% and Israel 0.9%. Among the 112 pts, 59.3% were male and 37.0% were aged 65 or older; median duration of imatinib treatment was 103.1 mts with median duration of CMR of 25.8 mts before imatinib discontinuation. To date, the median follow-up (FUP) time is 16.6 mts [95% CI: 14.9-18.2]. Forty-seven pts (43.5%, 95% CI: 34.0-53.4) of the 108 eligible pts relapsed and resumed imatinib; 38/47 (80.9%) of them relapsed in the first 9 mts and the last relapse occurred 19.6 mts after imatinib discontinuation. A loss of CCyR occurred in 11 pts (23.4%): 10/11 CCyR losses were recovered; 1 patient withdrew the consent shortly after obtaining a partial cytogenetic response. No case of CML progression was observed. After the resumption of imatinib the median time to either MMR or CMR was 1.9 [95% CI: 1.2-2.4] mts. Of the 61 not-relapsed pts, 43 (39.8% of the total) regained Q-RT-PCR positivity but never lost MMR. The median time to Q-RT-PCR positivity was 3.6 mts [95% CI: 3.0-4.8] and the range of duration of Q-RT-PCR positivity (below 0.1%) was between 5.7 and 29.2 mts. No significant correlation between relapse and previous duration of imatinib treatment, use of interferon, time to CCyR or duration of CMR was identified. An inverse relationship between pts age and risk of relapse is evident: 90% of pts 〈 45 years relapsed vs 37.5% in the class ≥ 45 - 〈 65 years and 27.5% of pts ≥ 65 years, p(χ2)

Description: Introduction. A substantial proportion of patients (pts) affected by Chronic Myeloid Leukemia (CML) achieve complete negativity in Q-RT-PCR. In this situation, as already demonstrated in other STOP trials, it is possible to safely discontinue imatinib treatment but it is still not clear how to discriminate subjects who will relapse. In fact even undetectable BCR-ABL may not equate to eradication of the disease because of the sensitivity of Q-RT-PCR. A new diagnostic method, the digital-PCR (dPCR), able to detect 1 BCR-ABL+ cell out of 107 cells, has been developed. Therefore, dPCR by assessing the presence of minimal residual disease with higher sensitivity, could potentially identify pts in whom CML has been eradicated. Aims. The ISAV study is aimed at validating the capability of dPCR to predict relapses after imatinib discontinuation in CML pts with negative Q-RT-PCR results and to evaluate relapse rate and timing of recurrence, survival and the impact of imatinib treatment on Quality of Life (QoL). Methods. This study involves 15 sites, 10 in Italy and 1 in each of the following countries: Germany, Spain, The Netherlands, Canada and Israel. CML pts (Chronic or Accelerated Phase) under imatinib therapy since more than 2 years and in complete molecular remission (CMR) were eligible. Patients had to be in CMR for at least 18 months (mts), with a minimum of 3 Q-RT-PCR performed at their own sites. After signing the informed consent, blood samples were obtained for dPCR and the pts discontinued imatinib therapy. Standard Q-RT-PCR is performed monthly (mts 1-6) and then bimonthly for 36 mts to assess the maintenance of the molecular remission. The loss of molecular remission is defined as two consecutive positive Q-RT-PCR tests with at least one BCR-ABL/ABL value above 0.1%. Patients losing molecular remission resume imatinib treatment at the same dosage used before interruption. Patients' QoL during imatinib discontinuation/resumption is evaluated through the EORTC QLQ-C30 questionnaire. Results. The study enrolled 112 pts with a median follow-up (FUP) time of 28.0 mts [95% CI: 25.5-30.1]. The 59.3% of pts were male and 37.0% were aged 65 or older; median duration of imatinib treatment was 103.1 mts with median duration of CMR of 25.7 mts before imatinib discontinuation. The cumulative probability of survival is 97.8% [95% CI: 91.4-99.5]. dPCR results showed that 23.1% of pts were positive and 75.9% negative, with a significant Negative Predictive Value ratio (dPCR/Q-RT-PCR) of 1.112 [95% CI: 1.009-1.225]. At 24 mts from imatinib discontinuation, 53 pts (49.1%, 95% CI: 39.3-58.9) of the 108 eligible pts relapsed and resumed imatinib; 73.6% of them relapsed in the first 9 mts and the last relapse occurred 21.8 mts after imatinib discontinuation. A loss of CCyR occurred in 13 pts (34.2% of those tested): 10/13 CCyR losses were recovered, the remaining 3 were not assessed for response. No case of CML progression or resistance to imatinib was observed. After the resumption of imatinib the median time to MMR/CMR was 1.9 [95% CI: 1.2-2.4] mts. Of the 55 not-relapsed pts, 42 (38.9% of the total) regained Q-RT-PCR positivity but never lost MMR. The median time to Q-RT-PCR positivity was 2.9 mts [95% CI: 2.0-3.1] in the relapsed pts and 4.5 mts [95% CI: 2.9-6.9] in pts who developed only PCR positivity. No significant correlation between relapse and previous duration of imatinib treatment, use of interferon, time to CCyR, Sokal score or duration of CMR was identified, while an inverse relationship between pts age and risk of relapse is evident. Moreover, age and dPCR results together can predict the risk of relapse: pts with less than 45 years and with a positive dPCR had the highest risk of relapse (100%) as opposed to pts ≥ 45 years and with negative dPCR (36.1%). The analysis of QoL evidenced a statistically significant improvement in the general well-being and symptoms scales at 1 month after imatinib discontinuation and in particular nausea, diarrhea and fatigue (p

Description: Introduction Imatinib induces complete cytogenetic response (CCyR) in up to 80% of chronic myeloid leukemia (CML) patients (pts) and major molecular response (MMR) in 33-60% of them. These patients enjoy life expectancy similar to general population. However even undetectable BCR-ABL may not equate to eradication of the disease because the sensitivity of the standard diagnostic method, the Q-RT-PCR, is limited. A new diagnostic method, the digital-PCR (dPCR), able to detect 1 BCR-ABL+ cell out of 107 cells, corresponding to a 100 times increased sensitivity as compared to conventional Q-RT-PCR, was developed (Goh HG et al., Leuk Lymphoma 52(5): 896-904. 2011). Therefore dPCR, assessing with more sensitivity the presence of minimal residual disease, could potentially identify pts in whom CML is eradicated. The Imatinib Suspension And Validation (ISAV) study is aimed at assessing the capability of dPCR to predict relapses after imatinib discontinuation in CML pts with negative Q-RT-PCR results. Methods This study involves 15 sites, 10 in Italy and 5 in each of the following countries: Germany, Spain, The Netherlands, Canada and Israel. In this study CML patients (Chronic Phase or Accelerated Phase) under imatinib therapy since more than 2 years and in complete molecular remission (CMR) were eligible. Patients had to be in CMR for at least 18 months, with a minimum of 3 Q-RT-PCR performed in their own centers. After signing the informed consent, pts were tested for dPCR and discontinued imatinib therapy. They are being monitored by standard Q-RT-PCR for 36 months to assess the maintenance of the molecular remission. At the end of this period, a peripheral blood sample for dPCR analysis will be obtained from those pts who will still have undetectable BCR-ABL transcripts by Q-RT-PCR, to verify CML eradication. The loss of molecular remission is defined as two consecutive positive Q-RT-PCR tests with at least one BCR-ABL/ABL value above 0.1%. Patients losing molecular remission resumed imatinib treatment at the same dosage used before interruption. Patients’ quality of life during imatinib discontinuation/resumption is being evaluated trough the EORTC – C30 Quality of Life questionnaire. Results The enrollment in the ISAV study began in November 2011 and ended in June 2013. The study enrolled 112 pts: Italy 69.6%, Berlin 21.4%, Montreal 5.3%, Zaragoza 2.6% and Tel Hashomer 0.9%. Sixty-one percent of the pts were male and 38% were aged 65 or older; median duration of imatinib treatment is 102 months with median duration of CMR of 32 months before imatinib discontinuation. To date, the median follow-up (FUP) time is 4.6 months [95% CI: 4.1-5.8] and 92 pts out of 112 (82%) had at least one Q-RT-PCR performed after imatinib discontinuation. The following analysis is restricted to 48 pts with a minimum of 6 months of FUP. Of these 48 pts, 20 remained Q-RT-PCR negative (42%, 95% CI:29-56%, median duration of negativity after imatinib discontinuation: 10.3 months). Nineteen pts (40%, 95% CI:27-53%) relapsed and resumed imatinib. All relapses occurred in the first 10 months and all but 3 of them in the first 6 months. A loss of CCyR happened in 5 pts out of 19 (26%): 1 pt regained CCyR after 3 months of re-treatment and is now in CMR, 1 pt died shortly after the diagnosis of relapse because of lung adenocarcinoma and 3 pts are now being monitored after imatinib resumption. No case of progression of CML was observed. After the resumption of imatinib the median time to either MMR or CMR, whichever came first, was 2.1 [95% CI: 0.9-5.8] months. Finally, nine pts (18%, 95% CI:10-31%) regained Q-RT-PCR positivity but never lost MMR. The median time to Q-RT-PCR positivity in this group of pts was 2.92 months (range 1-5 months), and the range of duration of Q-RT-PCR positivity (below 0.1%) is between 2 and 14 months. No significant correlation between relapse and previous duration of imatinib treatment, time to CCyR or duration of CMR was present. Patients previously treated with interferon showed a trend toward lower risk of relapse which is not significant so far. Finally, 19% of pts complained of musculoskeletal/articular pain after imatinib discontinuation. Conclusions After 21 months from the beginning of the study with a median follow-up of 4.6 months, 40% of pts relapsed; the majority of relapses happened in the first 6 months after imatinib discontinuation. The correlation of dPCR results with clinical outcomes will be presented at the meeting. Disclosures: le Coutre: Novartis: Honoraria; BMS: Honoraria; Pfizer: Honoraria; Novartis: Research Funding. Gozzini:Novartis: Consultancy; Bristol Myers Squibb: Consultancy.

Description: Introduction. It is known that imatinib can be safely discontinued in patients (pts) with Chronic Myeloid Leukemia (CML) with minimal residual disease. Here we report an update of the Imatinib Suspension And Validation (ISAV) study at 79 months (mts) from study initiation to provide long term follow up data. Aims. The ISAV study aims to validate the capability of digital PCR (dPCR) to predict relapses after imatinib discontinuation in CML pts with negative Q-RT-PCR and to evaluate relapse rate, time to recurrence, survival and the impact of imatinib treatment on Quality of Life (QoL). Methods. This study involves 15 sites, 10 in Italy and 1 in each of the following countries: Germany, Spain, The Netherlands, Canada and Israel. CML pts (chronic or accelerated phase) treated with imatinib for more than 2 years and in complete molecular remission (CMR) were eligible. Patients had to be in CMR for at least 18 mts, with a minimum of 3 Q-RT-PCR performed at their own sites. After discontinuation of imatinib therapy, Q-RT-PCR was performed monthly (mts 1-6), bimonthly for 36 mts and then every 6 mts for additional 2 years, to assess the maintenance of the molecular remission. The loss of molecular remission was defined as two consecutive positive Q-RT-PCR tests with at least one BCR-ABL/ABL value above 0.1%. Patients losing molecular remission resumed imatinib treatment at the same dosage used before interruption. dPCR was performed at screening and at 36 mts for those pts who were still in remission. Patients' QoL during imatinib discontinuation/resumption was evaluated through the EORTC QLQ-C30 questionnaire. Results. The ISAV study enrolled 112 pts with a median follow-up time of 60.0 mts [95% CI: 59.6-60.6] for pts who do not relapsed; 66.1% of them completed the study as per protocol. The 58.9% of pts were male and 37.4% were aged 65 or older; median duration of imatinib treatment was 103.2 mts with median duration of CMR of 25.6 mts before imatinib discontinuation. At 79 mts from imatinib discontinuation, 56 pts of the 107 eligible ones relapsed and resumed imatinib with a relapse rate of 52.3% [95%CI: 20.4-32.6]; 69.6% of them relapsed in the first 9 mts. Of the 52 not-relapsed pts, 40 (76.9%) regained Q-RT-PCR positivity without losing MMR. In this latter group 2 pts experienced late relapses, at 30.6 and 45.5 mts respectively. A loss of CCyR occurred in 13 pts (23.6%): 10/13 CCyR losses were recovered, the remaining 3 were not assessed for response. No case of CML progression or resistance to imatinib was observed. After the resumption of imatinib the median time to MMR/CMR was 1.8 [95% CI: 1.0-2.0] mts. No significant correlation between relapse and previous duration of imatinib treatment, use of interferon, time to CCyR, Sokal score or duration of CMR was identified, while an inverse relationship between pts age and risk of relapse was evident. dPCR results before imatinib discontinuation showed that 23.4% of pts were positive and 76.6% negative at the time of discontinuation, with a Negative Predictive Value ratio (dPCR/Q-RT-PCR) of 1.1 [95%CI: 0.99-1.22]. At 36 mts from imatinib discontinuation 80.4% [95%CI: 30.6-50.4] of the pts tested were positive in dPCR. Moreover, the results of dPCR performed at imatinib discontinuation and age together can predict the risk of relapse: pts with less than 45 years and with a positive dPCR had the highest risk of relapse (100%) as opposed to pts ≥45 years and with negative dPCR (36.1%). The analysis of QoL evidenced a statistically significant improvement in the general well-being and symptoms scales at 1 month after imatinib discontinuation, particularly with regard to nausea, diarrhea, fatigue and insomnia (p

Description: Abstract 3766 The independent, multicenter Imatinib Long Term Effects (ILTE) study assessed overall survival, loss of complete cytogenetic remission (CCyR), attainment of negative Philadelphia chromosome hematopoiesis assessed with quantitative polymerase chain reaction (PCR), serious adverse events (SAE), and toxicities not qualifying as SAE (NSAE) but judged by treating physicians as substantially affecting quality of life. The ILTE study also investigated the development of second tumours after at least two years of treatment. Consecutive CML patients, who started imatinib before 2005 and who were in CCyR after two years, were eligible. Overall survival, incidence of the first adverse events, and loss of CCyR were estimated according to the Kaplan-Meier method and compared with the standard log-rank test. Cumulative incidence of death was broken down into incidence related or unrelated to CML, accounting for competing risks. Standardized incidence ratio were calculated based on population rates specific for gender and age classes. The results at December 31st 2008 were published in J Natl Cancer Inst 2011; 103: 553–561. Here we report the results updated at December 31st, 2009, where a total of 832 patients were enrolled with a median treatment duration of 6.7 years. A comparison of the observed mortality rate in CML patients with the rate in the general Italian population showed no excess mortality. Thirty-three deaths were observed (8 CML-related), with a mortality incidence rate of 0.8 per 100 person-years (standardized incidence ratio = 0.85; 95% CI = 0.58 to 1.19). Similar results were obtained when this analysis was restricted to Italian patients. The CML-related death rate was 0.12 per 100 person-years. There were 139 recorded SAE, of which 19.4% were probably related to imatinib. Among the 830 NSAEs (which developed in 57.8% of patients and were possibly related to imatinib in 68.2% of the 830 events), the most frequent ones were muscle cramps, asthenia (observed in 4.9% of patients), edema, skin fragility, diarrhea, conjunctival hemorrhages, osteoarticular pain and tendon or ligament lesions. Nineteen patients (2.3%) discontinued imatinib because of drug-related toxicities. Fifty-three patients lost CCyR, corresponding to a rate of 1.4 per 100 person years (1.1% in patients who received imatinib as first line treatment). Durable (greater than 1 year) Philadelphia negative hematopoiesis, as evaluated by PCR was attained by 125 patients (15%). The onset of second tumours was also evaluated: 34 patients developed second cancers. The overall rate was not significantly different from that of the general population (SIR = 0.9, 95% CI = 0.63 to 1.26), with the exception of prostate cancer (SIR = 2.86; 95% CI = 1.48 to 4.99). In conclusion, CML-related deaths are uncommon in CML patients who are in CCyR two years after starting imatinib. Survival is not statistically significantly different from that of the general population. Side effects are present but generally not serious. A higher incidence of prostate cancer, to be confirmed and further analyzed, was observed. Disclosures: No relevant conflicts of interest to declare.