Minimal residual disease and normalization of the bone marrow after long-term treatment with alpha-interferon2b in polycythemia vera. A report on molecular response patterns in seven patients in sustained complete hematological remission
Abstract Background : Polycythemia vera (PV) is a clonal myeloproliferative disorder characterized by the presence of the JAK2V617 mutation in virtually all patients. Recently several studies have shown that the JAK2V617F mutational load decreases during treatment with alpha-interferon2 (1–6). Aim: To report on molecular and histomorphological bone marrow responses in seven PV patients with complete molecular remissions during and after long-term treatment with alpha-interferon 2b. Patients: Seven patients treated with alpha-interferon2b for a median of 84 months (range 31–120) are reported. In four of the patients alpha-interferon2b was started at the time of diagnosis and in three patients 9, 36 and 42 months from the time of diagnosis, respectively. Methods: The mutation was determined by allele specific PCR (n=2 only) (7) and quantitative PCR (qPCR) (n=5) (8). In three out of these patients qPCR JAK2V617F was performed on archived bone marrow from diagnosis (2 patients) and on peripheral blood (one patient) prior to treatment with alpha-interferon2b. A complete molecular remission (CMoR) was defined by less than 2 % JAK2 V617F mutated alleles (7). Results: Molecular Responses. All patients obtained a CMoR after a median of 84 months (29–120 months) of treatment with alpha-interferon2b. Subsequently all patients have discontinued alpha-interferon with a follow-up period of median 10 months (range 4–30 months) and sustained complete hematological remission. Furthermore, in three patients molecular responses have recently been updated – April and May 2008 - showing CMoRs in all (1,2 %, 0,9 % 0,1 % mutated alleles, respectively). Bone Marrow Responses. Follow-up bone marrow biopsies were available in five patients. Complete normalization of the bone marrow was seen in three patients after treatment with alpha-interferon2b for 84, 132 and 132 months, respectively. In the bone marrow from the patient being treated with alpha-interferon for 132 months a qPCR JAK2V617 analysis was performed detecting the mutation at a very low level (0,5 % mutated alleles). In two other patients, being treated with alpha-interferon2b for 24 and 120 months, respectively, and having obtained a CmoR in peripheral blood the bone marrow histomorphology showed marked regression of PV-features but in both patients still with focal areas displaying an increased number of morphologically abnormal megakaryocytes. Updated histomorphological and molecular response patterns will be presented. Discussion and Conclusion : Previous studies on the molecular response during alpha-interferon2a treatment have shown that a substantial proportion of patients achieve a significant molecular response after 12 months with a continuous decrease in the JAK2V617F mutation load at 24 and 36 months (1,5,6). This report confirms and extends preliminary data, showing that long-term treatment with alpha-interferon 2b in a subgroup of PV-patients is able to induce complete molecular remissions with normalization of the bone marrow morphology, which may even be sustained after discontinuation of alpha-interferon2b for up to 20 months (5). Prolonged treatment for several years seems necessary to induce such sustained responses, since treatment for only a few months has been reported to be followed by rapid recurrence of clonal hematopoiesis (9). In conclusion, a state of “minimal residual disease” may be achieved in PV by long-term immune therapy using alpha-interferon 2. Our observations call for large prospective clinical studies in which treatment with alpha-interferon is initiated up-front in patients with JAK2-positive PV and allied diseases. These studies should also aim at exploring the minimal dose of alpha-interferon needed to elicit complete molecular responses in order to minimize side effects of the drug and accordingly diminish the high drop-out rates reported in most previous studies.
Abstract Abstract 3767 Background With the introduction of imatinib (IM) and subsequent TKIs such as nilotinib (NI) and dasatinib (DA), deaths due to progression of chronic myeloid leukemia (CML) have decreased dramatically. In such circumstances, the new occurrence of other malignant diseases in patients with CML on treatment with TKIs always causes distress. With the increase in long term surviving patients with CML, there is concern over whether these malignancies are related to treatment with TKIs or not. We investigated the improved prognosis in patients with CML on long-term treatment with TKIs and the occurrence of complicating malignancies. Methods We evaluated 173 patients (101 males, 72 females) in the chronic phase of CML, all of whom had CML diagnosed at our hospital between January 1990 and June 2011 and received treatment with TKIs for at least 1 year. The median age at the start of treatment with TKIs was 57 (19 – 92) years. Patients aged 60 years and older accounted for 72 (42%). The median follow-up period after the start of treatment with TKIs was 68 (12 – 128) months. Before the onset of CML, 11 patients had prior malignancies. Treatments for CML administered before use of TKIs were hydroxyurea (HU) alone 3, HU + interferon-α (IFN-α) 47, IFN-α alone 7, chemotherapy for AML + IFN-α 2 and chemotherapy for ML + IFN-α 1. TKIs were used as frontline therapy in 113.TKI treatment of all patients initially consisted of IM at the dose of 100 mg per 12 kg body weight. We switched the drug to NI when complete molecular response (CMR) was not achieved after long-term treatment with IM. In addition, a switch to DA was used to consolidate CMR. Treatments that contained TKIs consisted of IM alone in 42, IM → NI in 46, and IM →NI → DA in 85. Two patients with a complete cytogenetic response (CCR) underwent bone marrow transplantation. Results Among 173 patients, the best response to treatment in patients treated with TKIs was CMR in 72, a major molecular response (MMR) in 84, CCR in 15, and refractory CML in 2. Currently, 22 have maintained CMR for 6 to 111 months after discontinuation of TKIs, and 19 (11%; 17 males, 2 females) have developed new onset of a malignancy. In these 19, the median age at the onset of cancer was 70 (31 – 85) years. Patients aged 60 years and older accounted for 15 (79%). The median period from the start of TKIs to the onset of cancer was 38 (10 – 117) months. Affected organs were bladder 5; stomach 3; rectum 3; large intestine 2; lung 2; and esophagus, appendix, prostate, and pancreas each in 1. The TKIs given to the patients with malignant diseases were IM alone in 13, IM → NI in 4, and IM → NI → DA in 2. Prior treatments included HU + IFN-α in 8 and IFN-α alone in 1. The observed number of patients who were diagnosed as malignant neoplasm was compared with the expected number. The expected number was obtained through integration of age specific incidence rate of malignant neoplasm from the start age taking medicine to the age at which the diagnosis as malignancy was made or the follow up was finished for censoring. The age specific incidence rates were estimated by interpolating five year old specific incidence rates from of the 2007's survey that was conducted by Center for Cancer Control and Information Services, National Cancer Center, Japan. The observed number/expected number (O/E) ratio for the occurrence of all malignant diseases was 1.00 (19/18.97), and the O/E for gastrointestinal cancer was 1.118 (11/9.84). Therefore, no increase in the incidence of malignant diseases was observed in patients treated with TKIs. However, the O/E for bladder cancer was 4.525 (5/1.11) with a 95% confidence interval of 1.42 – 9.32 (P = 0.0002), which means that the incidence of bladder cancer in patients treated with TKIs was higher than that in the general Japanese population. So far 19 patients have died and the median age at death was 79 (59 – 94) years. In these patients, 8 deaths were related to cancer and the others were caused by diseases associated with old age that were unrelated to the worsening of CML. Conclusion The introduction of TKIs has undoubtedly improved the prognosis of patients with CML. Based on the results of this investigation, the apparent increase in malignant diseases observed during the long-term follow-up of patients treated with TKIs was generally considered to be attributable to the aging of patients. We should however further investigate whether the higher incidence of bladder cancer seen in patients treated with TKIs is incidental or not. Disclosures: No relevant conflicts of interest to declare.
Abstract Background Radioimmunoconjugates are effective treatment in relapsed/refractory follicular lymphoma (FL) when used as single agents, and can result in effective disease control (Kaminski et al, NEJM 1993; Witzig, JCO 2002). When used as consolidative treatment following a course of initial chemotherapy for patients with newly diagnosed FL, durable remissions have been noted (Gordon LI et al, Blood 2004). As a pure high energy beta emitting isotope, Zevalin has several advantages and has been well studied in relapsed refractory indolent NHL (Witzig TE et al, JCO 2002). Therefore, our hypothesis is that radioimmunoconjugates significantly change outcome for patients with FL when given in a situation of minimal residual disease, and number of long term remissions would increase with initial cytoreduction. For cytoreduction, we chose to use an outpatient formulation of ESHAP (etoposide, methylprednisolone, cytarabine, cisplatin): ESHAP has excellent efficacy as a salvage regimen in treating relapsed low-grade lymphomas (Rodriguez-Monge EJ et al, Hem Oncol Clin N Am, 1997). Further, it is not utilized by community oncology practices fostering chemo sensitivity in a relapsed setting. Methods Histologically confirmed CD 20 + relapsed FL, ≥1< 4 prior therapies, age 18, ECOG performance status 0–2, measurable disease, signed informed consent, creatinine, bilirubin< 2.0 x ULN , platelet counts ≥150,000 able to receive 0.4 mCi/kg of Zevalin; patients with platelet counts 100,000-150,000 received 0.3mCi/kg dose of Zevalin. Patients were treated with 2 cycles of ESHAP every 28 days. At subsequent restaging, if bone marrow aspirate, biopsy showed<25% involved and expected biodistribution, Zevalin was administered. If Bone marrow involvement was >25 % was noted, patients were taken off study secondary to treatment failure. Results Twenty-eight patients with FL were enrolled with total 8 year follow-up. 6 patients did not complete the study: one patient was ineligible secondary to re-review of path showing DLBCL. Three patients were ineligible for study completion secondary to bone marrow showing residual involvement. Two patients withdrew secondary to toxicities: one from a perforated duodenal ulcer (SAE), and one from side effects of ESHAP chemotherapy including nausea, progressive functional decline. Other Grade 3, 4 adverse events included myelosuppression. Twenty-two patients were evaluable for response. Of the 22 evaluable patients, the overall response rate was 72% (17/22) with another 13 % achieving stable disease. After follow-up of 8 years, the median progression free survival (PFS) was 10 months for both the intent to treat analysis and responders (p=0.14). The median overall survival (OS) in the intent to treat analysis was 63 months, and the median OS in the 8 year follow-up of responders has not been reached (p=0.02). When analyzed by median number of prior therapies, the median PFS for patients with more than one prior chemotherapy regimen was 9, whereas the median PFS for patients with one prior regimen was 22 months. Similarly, for patients with more than one prior therapy, the median OS was 54 months, whereas the median OS for patients with one prior regimen has not been reached at 8 year follow-up. Conclusions In prior long term follow-up data(7 years) of a phase I/II study of Zevalin (Gordon et al, Blood 2004) in NHL including FL, the median time to progression in responders was 12.6 months, and durable responses were noted in 5/51 patients with FL. In a phase II study of relapsed FL treated with Zevalin (Witzig et al, JCO 2002) the median time to progression was 6.8 months, and in a subsequent Phase III study comparing Zevalin to rituximab, the median time to progression was 11.2 months. In comparison to above studies, our study has shown that outpatient ESHAP is an effective cytoreductive regimen. Zevalin is active when administered in a setting of minimal residual disease early in the disease course as evidence by the excellent overall survival of the responders. Disclosures: Off Label Use: Use of the investigational agent MLN8237 in combination in patients with aggressive B-cell NHL. Persky:Millennium: The Takeda Oncology Company: Research Funding.
Abstract Background: Numerous studies from others and our institution have demonstrated that the presence of minimal residual disease (MRD), detected at the time of hematopoietic cell transplantation (HCT), is strongly and independently associated with increased relapse risk and short survival in adults with acute myeloid leukemia (AML) undergoing myeloablative allogeneic HCT in morphologic complete remission (CR). In contrast, very little information is available regarding the prognostic significance of peri-transplant MRD dynamics in these patients. Since bone marrow staging studies with multiparameter flow cytometric (MFC) assessment for MRD are routinely obtained not only before but also at approximately day +28 following transplantation at our institution, we here retrospectively studied the relationship between peri-HCT MRD dynamics and post-transplant outcomes in a large patient cohort. We asked whether persistence or disappearance of MRD might identify cohorts of patients in whom post-transplant therapy was particularly indicated or unnecessary. Patients and Methods: AML patients ³18 years of age were eligible for this retrospective analysis if they were in first or second morphologic CR or CR with incomplete blood count recovery (CRi) irrespective of the presence of MRD, underwent allogeneic HCT with myeloablative conditioning between 2006 and 2014, received peripheral blood or bone marrow as stem cell source, and had pre-HCT bone marrow staging studies available that included 10-color MFC assessments for MRD. MRD was identified as a cell population showing deviation from normal antigen expression patterns compared with normal or regenerating marrow; any level of residual disease was considered MRDpos. We considered post-HCT MRD assessments in patients in whom bone marrow re-staging with MFC MRD analysis were obtained 28±7 days after transplantation. For this analysis, the primary endpoint of interest was overall survival, which was estimated using the Kaplan-Meier method. Results: 311 patients were identified and included in this study. Consistent with our previous analyses, patients with MRD at the time of HCT (MRDpos; n=76) had significantly shorter survival than MRDneg patients (n=234; estimated 3 year post-HCT survival: 26% [95% confidence interval: 17-37%) vs. 73% [66-78%], P <0.001). 310 patients survived at least 21 days following transplantation; for 279 of these (89.7%), post-HCT MRD assessments were obtained at day +28±7 and available for analysis. 214 patients (76.7%) had no MFC evidence of MRD before and after HCT (MRDneg/MRDneg), 2 (0.7%) were MRDneg/MRDpos, 49 (17.6%) were MRDpos/MRDneg, and 14 (5.0%) were MRDpos/MRDpos. Of the 65 patients who had detectable MRD either before and/or after transplantation, 58 had decreasing levels of MRD (MRDdecr) over the peri-HCT period, whereas 7 patients had increasing MRD levels (MRDincr) around the time of transplantation. As depicted in Figure 1, MRDneg/MRDneg patients had excellent long-term outcomes (survival at 3 years after day +28 MRD assessment: 76% [69-82%]), whereas both MRDneg/MRDpos patients died within 70 days after the day +28 MRD assessment. Interestingly, for patients who were MRDpos before transplantation, outcomes were relatively poor regardless of whether or not they had persistent MRD around day +28 after transplantation (MRDpos/MRDneg patients: 23% [12-36%]; for MRDpos/MRDpos patients: 19% [4-44%]). However, long-term survival was only observed among MRDdecr patients (at 3 years after day +28 MRD assessment: 24% [14-37%]), whereas all MRDincr patients died a median of 97 (range: 15-808) days following the post-HCT MRD assessment (Figure 2). Conclusion: Patients who have no evidence of MRD before and after HCT have excellent long-term outcomes. In contrast, patients who are MRDpos before transplantation have poor survival expectations regardless of whether or not they clear MRD within the first 28 days after transplantation, but long-term survival is only found among some patients with decreasing MRD levels over the peri-transplant period. This finding suggests that patients who are MRDpos at the time of HCT should be considered for pre-emptive therapeutic strategies given their high risk of disease recurrence regardless of the day +28 MRD information. Figure 1. Figure 1. Figure 2. Figure 2. Disclosures Radich: Incyte: Consultancy; Ariad: Consultancy; Gilliad: Consultancy; Novartis: Consultancy, Research Funding. Walter:Amphivena Therapeutics, Inc.: Consultancy, Research Funding; Seattle Genetics, Inc.: Research Funding; Covagen AG: Consultancy; AstraZeneca, Inc.: Consultancy; Pfizer, Inc.: Consultancy; Amgen, Inc.: Research Funding.
Abstract Background Ropeginterferon alfa-2b (AOP2014/P1101) is a novel long-acting pegylated IFN-alpha-2b, composed of mainly one isoform, resulting in longer half-life and exposure time. Reduced dosing frequencies, better tolerability, improved compliance and more favorable long-term treatment outcomes in patients with polycythemia vera (PV) are expected. The drug has Orphan designation by EMA and FDA and is currently in the phase III stage of development. Study design Efficacy and safety data are being collected in the follow-up extension stage of the study (collecting the data of both Phase I and Phase II portions of the study), after the maximum tolerated dose (MTD) of ropeginterferon alfa-2b, administered subcutaneously every 14 to 28 days, has been defined earlier. Patients with confirmed diagnosis of PV, age ≥18 years, both naïve and cytoreductively pre-treated were eligible. After establishing the MTD, an extended cohort of 25 additional patients has been planned to be recruited. Complete hematological response (CR) is defined by hematocrit (Hct)<45%, platelet count≤400*109/L, WBC count≤10*109/L, normal spleen size by sonography, and absence of thromboembolic events. Partial response (PR) is defined as Hct<45% without phlebotomy but with persistent splenomegaly or elevated (>400*109/L) platelet count, or reduction of phlebotomy requirements by at least 50%. Complete molecular response has been defined as reduction of any molecular abnormality to undetectable levels; partial molecular response as: reduction ≥ 50% in patients with < 50% mutant allele burden, or a reduction ≥ 25% in patients with > 50% mutant allele burden. The present analysis was focused on long-term tolerability and safety in correlation with the dose of ropeginterferon alfa-2b in PV. Results Data on treatment as by July, 24, 2015, are covered by the current analysis. Baseline characteristics of the study cohort during short-term treatment were already presented earlier (Gisslinger et al, ASH 2013). The full analysis set and efficacy set were composed of 51 and 47 patients, respectively. Currently, the median reported treatment duration is 138 weeks, 33 patients completed their follow up for two years, 19 for three years. Starting with the week 10, Hct-level, platelet- and WBC-counts could be constantly maintained within normal range in the majority of patients. In a group of patients with the mean administered dose of <300 µg ("low dose", n=36), CR as best individual response was achieved in 20 (56%) patients, and PR in 14 (39%) compared to the CR and PR in the high dose (>300 µg, n=11) group of 8 (73%) and 3 (27%) respectively. However, no statistical significance can be observed if correlation between the dose and response status was analyzed. 30 patients are still being treated in the study. Similarly, no association between the dose and occurrence of adverse events in the study could be observed. Complete molecular response as best individual response was observed more frequently in the high dose group 4 (36%) compared to 8 (23%) in the low dose group, while partial molecular responses were equally frequent in both dose groups (in 6/55% and 20/57%, respectively). 21 patients discontinued the study, 18 being treated with AOP2014 doses corresponding to low, and 3 to the high dose arms, corresponding to the drop-out rate of 50% and 27% in the respective arms. Interestingly, all discontinuations in the high dose group occurred within the first year of treatment (at weeks 16, 18 and 32), while the drop-outs in the low dose group (6 patients, 33%) discontinued the study after completion of their first year of treatment. Conclusions Efficacy and safety profile remain in line with expectations from other (pegylated) interferons. Overall response rate of >80% with cumulative CRs in 45-50%, accompanied by phlebotomy independence, normalization of hematological parameters and spleen size reduction in majority of patients have been observed. Significant and sustained JAK2 allelic burden decrease, starting from week 28 of treatment, was seen. No significant difference between the two mean dose levels regarding response rates or adverse events even during long-term treatment and observation could be observed. These finding are to be further verified in a larger prospective setting. Disclosures Gisslinger: Celgene: Consultancy, Honoraria, Research Funding, Speakers Bureau; Novartis: Honoraria, Research Funding, Speakers Bureau; AOP ORPHAN: Consultancy, Honoraria, Research Funding, Speakers Bureau; Geron: Consultancy; Sanofi Aventis: Consultancy; Janssen Cilag: Honoraria, Speakers Bureau. Buxhofer-Ausch:AOP Orphan: Research Funding. Thaler:AOP Orphan: Research Funding. Schlögl:AOP Orphan: Research Funding. Gastl:Novartis: Membership on an entity's Board of Directors or advisory committees, Research Funding; AOP Orphan: Research Funding. Ban:AOP Orphan: Research Funding. Egle:AOP Orphan: Research Funding. Melchardt:AOP Orphan: Research Funding. Burgstaller:AOP Orphan Pharmaceuticals: Honoraria, Research Funding; Novartis: Honoraria; Mundipharma: Honoraria; Celgene: Consultancy, Honoraria, Research Funding. Willenbacher:COMET Center ONCOTYROL: Research Funding; AOP Orphan: Research Funding. Kralovics:AOP Orphan: Research Funding; Qiagen: Membership on an entity's Board of Directors or advisory committees. Zörer:AOP Orphan: Employment. Ammann-Mwathi:AOP Orphan: Employment. Kadlecova:AOP Orphan: Consultancy. Zagrijtschuk:AOP Orphan: Employment. Klade:AOP Orphan: Employment. Greil:Pfizer: Honoraria, Research Funding; GSK: Research Funding; Boehringer-Ingelheim: Honoraria; AOP Orphan: Research Funding; Celgene: Consultancy; Janssen-Cilag: Honoraria; Genentech: Honoraria, Research Funding; Novartis: Honoraria; Astra-Zeneca: Honoraria; Amgen: Honoraria, Research Funding; Ratiopharm: Research Funding; Sanofi Aventis: Honoraria; Merck: Honoraria; Mundipharma: Honoraria, Research Funding; Eisai: Honoraria; Cephalon: Consultancy, Honoraria, Research Funding; Bristol-Myers-Squibb: Consultancy, Honoraria; Roche, Celgene: Honoraria, Research Funding.
The Presence of Minimal Residual Disease, As Determined By Highly Sensitive Quantitation of NPM1-Mutatation, Provided Powerful Prognostic Information in Acute Myeloid Leukemia
Background: As recurrence of acute myeloid leukemia (AML) is difficult to predict, it is important to detect it by measuring minimal residual disease (MRD). PML-RARA, RUNX-RUNX1T1, CBFB-MYH11 are regarded as the reliable MRD markers. However, in AML with normal karyotype and many other forms, no MRD markers have been established. NPM1 mutations, occurring in approximately 30% of adult AML cases, and 50-60% of AML cases with normal karyotype, represent one of the most frequent mutations in AML. Recently, NPM1 mutation is reported to be useful in assessing MRD. We undertook a retrospective and prospective investigation of the usefulness of NPM1 mutation as an MRD marker in Japanese patients with AML. Methods: The subjects were 38 NPM1-mutated AML patients with first hematological remission at several hospitals related to our institution between 2001 and 2018. This study was approved by the ethics committee of Nippon Medical School and the informed consents were obtained from all patients, according to the Declaration of Helsinki. We analyzed peripheral blood cells or bone marrow cells at diagnoses, and evaluated only bone marrow cells after diagnoses. Detection of NPM1 mutation was carried out using allele-specific real time PCR following creation of a complementary primer. After dilution of the samples, sensitivity to TCTG, CATG, and CCTG was found to be 0.001%. The NPM1 mutant copies were qualified only at successful amplification of internal control. Results: The median age of the patients was 58 years (18-79 years). There were 32 cases with intermediate cytogenetic prognosis and 6 cases with unclear chromosomal profile. Of the 38 cases, 14 cases (37%) were FLT3-ITD-positive and allogeneic hematopoietic stem cell transplantation was carried out in 14 cases (37%). The base sequence was TCTG in 36 cases and CCTG in 2 cases. Persistence of NPM1-mutatation was present in 25 patients with first hematological remission (66%). Compared with patients with MRD negative, patients with MRD positive were associated with DNMT3A mutation (MRD positive 12/25 vs MRD negative 0/13, p=0.003). The rate of relapse in patients with MRD positive was significantly higher than those of in patients with MRD negative (MRD positive 76% vs MRD negative 23%, p=0.004). The rates of relapse free survival (RFS) and overall survival (OS) in patients with MRD positive were significantly lower than those in patients with MRD negative (RFS at 2 years: MRD positive 14% vs MRD negative 86% p=0.003; Figure 1, OS at 2 years: MRD positive 25% vs MRD negative 93%, p<0.001). In FLT3-ITD negative group, the rates of RFS in patients with MRD positive were significantly lower than those in patients with MRD negative. (RFS at 2 years: MRD positive 21% vs MRD negative 92% p=0.001; Figure 1). Conclusion: The presence of MRD with NPM1 mutation is significantly associated with relapse and it is useful to decide their treatment strategy. Especially, there is the usefulness of NPM1 mutation as an MRD marker in NPM1 positive Flt3-ITD negative AML patients who are generally classified as favorable risk. According to previous reports, it is known that NPM1-mutated AML sometimes relapse with losing NPM1 mutations. However, in this study, all NPM1-mutated AML relapse without losing NPM1 mutations. We need to collect more patients and are going to confirm whether there are patients who relapse with losing NPM1 mutations or not. We plan to analyze the genetic background of MRD positive and negative patients with next-generation sequencing. We are going to announce the genetic characteristics in addition to this result at ASH. Disclosures Usuki: Astellas Pharma Inc: Research Funding, Speakers Bureau; Daiichi Sankyo Co., Ltd.: Research Funding, Speakers Bureau. Kako:Bristol-Myers Squibb: Honoraria; Pfizer Japan Inc.: Honoraria. Inokuchi:Bristol-Myers Squibb: Honoraria, Research Funding; Novartis: Honoraria; Celgene: Honoraria; Pfizer: Honoraria.
Abstract From 9/98 to 11/99, 126 patients with symptomatic previously untreated or first relapse (< 6 months of chlorambucil and/or local radiotherapy) CD20+ low-grade lymphoma, were included in a multicenter randomised phase II study. The treatment consisted of a first cycle of rituximab 375 mg/sqm q wk x 4. Pts in CR at week 14 were observed with no further treatment until symptomatic relapse, while pts with SD or PD went off study. Pts with PR or minor response were randomised to receive either a second cycle of rituximab 375 mg/sqm q wk x 4 or interferon-alpha-2a (IFN) 3 MIU/day sc (wk 1), 4,5 MIU/day (wk 2–5) in combination with rituximab 375 mg/sqm q wk (w 3–6). The clinical data from this study has previously been reported (Kimby E, et al. Ann Oncol2002;13 (Suppl 2):85). 38 patients (30%) fulfilled the criteria for CR, and were eligible for analysis of minimal residual disease (MRD). 14 more patients achieved CR at a time point later than first follow up after end of treatment. Per protocol, these patients are not included in the present analysis. By standard DNA-based PCR, presence of either a t(14;18) fusion transcript (MCR/mbr) or a clonal rearrangement of the Ig heavy chain (CDR3) could be detected in the diagnostic bone marrow and blood sample from 23 patients. These patients have now been studied for MRD, with a median follow-up time of 62 months. In dilution experiments the sensitivity of the assays was between 1:10−3 and 1:10−4. A given sample was considered negative if the PCR reaction was negative in three independent experiments, using up to 2 μg of template DNA. Patients were tested in blood and bone marrow at 10–16 weeks, 38–40 weeks and 52 weeks following treatment. A total of 175 samples, including 49 samples from patients in continued CR up to 5 years after treatment, have been analysed. Of 72 paired blood and bone marrow samples, only three showed inconsistency between blood and bone marrow, all three being positive in bone marrow and negative in blood. The frequency of MRD negativity 10–16 weeks after treatment was 4/9 (44%) in patients who received 1 cycle of rituximab, 3/5 (66%) in patients who received two cycles of rituximab and 7/9 (77%) in patients who received two cycles of rituximab with IFN priming. This trend towards a dose-response relation was however not significant, due to the small number of patients in each treatment group. The median duration of CR in patients who were negative at all three timepoints during the first year (n=14) was 62 months, compared to 21 months in patients (n=9) with one or more positive samples (p<0,005). At a median follow up of 62 months 9/14 patients who were MRD negative through the first year remain in complete molecular remission, compared to 1/9 patients who had one or more positive blood or bone marrow samples during the first year (p<0,03). Thus, sustained long-term complete molecular remissions are achievable with rituximab alone or in combination with IFN, and predictable by MRD status during the first year post treatment. Whether the quality of response is related to the dose of rituximab or the combination with IFN, and whether the response can be predicted using blood samples alone, must await the results of the ongoing ML16865 randomised phase III trial of rituximab vs IFN/rituximab in the same group of patients.
Abstract Abstract 1390 Introduction: Levels of minimal residual disease (MRD) have been shown to correlate with PFS in previously untreated patients with CLL (CLL8, Boettcher et al. Leukemia, 2009). Patients who remain MRD positive after treatment have a higher risk of relapse. Eradication of MRD is therefore a desirable clinical endpoint of treatment. We were interested to assess this correlation in REACH, a randomized international clinical study in previously treated CLL patients, randomized 1:1 for treatment with rituximab, fludarabine and cyclophosphamide© R-FC (276 patients) or FC alone (276 patients); (Robak et al. JCO 2010). Methods: While MRD quantification by flow cytometry requires an identifiable stable phenotype and fresh blood samples, PCR based methods can be performed centrally on frozen samples. We have therefore developed a Realtime Quantitative (RQ) PCR method, using patient-specific IgVH (immunoglobulin variable heavy chain) gene rearrangements as targets. Briefly, genomic DNA was isolated from CD19 sorted B-cells. ASO (allele-specific oligonucleotide) primers were designed matching the hypervariable N-D-N region of the patient-specific leukemic clone and used with reverse consensus primers and hydrolysis probes annealing to the family-specific joining region of the IGH rearrangement (Brüggemann et al., Leukemia, 2004). Maximum sensitivity and quantitative range were defined for every RQ-PCR. Patients were categorized as molecular responders (MRD negative) if there was no detectable clonal IgH rearrangement, using a sensitivity cut-off of 1×10-4. Molecular response was assessed at the time of CR confirmation and 6 months later (if CR was maintained). Results: Among the 103 patients who achieved CR during the study, 86 patients had at least one MRD assessment in peripheral blood, 92 patients in bone marrow. Since many patients had a CR confirmation at different time points during the follow-up period, we initially analyzed the MRD levels only in patients who had achieved confirmed complete response at end of treatment +/−3 month (“EOT - period”). The rate of MRD negativity in blood (22 pts: 5(15) FC, 6(7)R-FC) at EOT was 33% for patients treated with FC, and 86% for patients treated with R-FC (p=0.06); In bone marrow at the EOT (61 patients: 5(27) FC, 20(34) R-FC) the rates were 19% and 59%, respectively (p= 0,02), indicating higher efficacy of the Rituximab containing regimen in eradication of residual disease; This is in line with the previously reported results using FACS analysis of MRD in the CLL8 trial; the differences in the detection rate in blood versus bone-marrow, suggest a higher sensitivity for detection of MRD in bone marrow. We therefore compared the levels of MRD negativity in samples from blood and bone marrow in patients where both samples were taken at the same time point. Results were concordant in 8/9 patients, one patient had a positive result in bone marrow with no detectable signal in blood. This supports the notion that assessment of MRD in bone marrow of CLL patients may be more sensitive than assessment in blood only. However, for a definitive statement larger sample size would be needed. We then correlated MRD status at EOT, regardless of treatment arm, with PFS: In line with previous reports, there was a clear trend to longer PFS in patients who had reached MRD negativity (median PFS not reached), while patients with residual disease had shorter PFS; however, due to small sample numbers, statistical significance could not be reached. We also analyzed the correlation of MRD negativity reached at any time during and after treatment with PFS, bearing in mind that this sample set is inherently biased, since patients with early progression will be lost from the analysis; the results are consistent with the EOT findings. Summary: ASO IgVH RQ-PCR is a powerful method to detect residual levels of disease in CLL patients with clinical complete response and undetectable MRD correlates with longer PFS. Among patients in REACH achieving clinical CR on either study arm, a higher percentage achieved MRD negativity on the R-FC arm, consistent with the increased efficacy shown for the Rituximab treatment arm by the REACH clinical data. Disclosures: Mundt: Roche: Employment. Smith:Roche: Employment. Lin:Genentech: Employment. Barrett:Roche: Employment. Hurst:Genentech: Employment. Geisler:Roche: Research Funding, Speakers Bureau. Hiddemann:Roche: Research Funding.
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.