ALBERT

Description: We have conducted a retrospective study of 82 patients (49 - male, 33 - female, median age 67 years (Male), 63 years (Female) ) of whom 72 were de novo and 10 had a previous diagnosis of MGUS/Smouldering myeloma/Plasmacytoma. The duration of symptoms prior to diagnosis was used to categorise patients into 4 groups [A - 0 - 3months, B - 3 -6 months, C - 6 - 12 months, D 〉 12 months]. The incidence of complications of myeloma (infection, renal failure, bone disease, neurological disease and anaemia) were assessed in each group. 25 of 72 patients (35%) were in group A, 47 (65%) were in group B,C and D and 30 of these (64%) had presented initially to a general practitioner. The commonest presenting symptom was bone pain (60%) and skeletal disease was the commonest complication seeing in 43% of group A but in 57% of groups B,C and D. All 18 patients in group D had 〉 1 complication (median 2, range 1–4) while 9 of 25 patients (35%) in group A had no complication. Four of 25 (16%) patients in group A were in remission or first phase of treatment and 7 of 25 (28%) had survived 5 years or more. In contrast, 9 of 18 (50%) patients in group D had relapsed disease and only 2 had survived 5 years or more. Our findings indicate that a delay in diagnosing multiple myeloma has a significant impact on the course of the disease.

Description: Pts with CML resistant to im have few therapeutic options. A growing body of evidence suggests that treatment outcomes can be improved with increased potency of BCR-ABL inhibition. Escalating the dose of im to 800mg/day (d) can overcome some cases of im-resistance, but tolerability and durability of response are significant issues. Dasatinib (SPRYCEL®, formerly BMS-354825) is a novel, oral, multi-targeted kinase inhibitor of BCR-ABL, SRC, and other kinases that is approximately 300 times more potent than im in vitro. Dasatinib has been shown to be effective and safe in pts with CML resistant or intolerant to im, leading to recent FDA approval. START-R is an international trial of dasatinib 70mg twice daily (BID) and im 800mg/d in pts with CP-CML resistant to prior im 400–600mg/d. Crossover was allowed upon confirmed progression or intolerance despite dose reduction (grade 3/4 non-hematologic toxicity). Dasatinib dose escalation to 90mg BID was allowed for inadequate response at 12 wks, and dose reduction to 50 or 40mg BID for toxicity. Dose reduction of im to 600mg/d was allowed for patients who had not previously received that dose. Major cytogenetic response (MCyR) rate at 12 weeks was the primary endpoint. From Feb–Nov 2005, 150 pts were randomized (2:1), 101 to dasatinib, 49 to im. MCyR to prior im had been seen in 28% of dasatinib and 29% of im pts. With a minimum follow-up of 10 mo, complete hematologic response (CHR) rate was 92% (93 dasatinib pts) vs 82% (40 im pts), and MCyR rate was 48% dasatinib vs 33% im. Of importance, the primary difference was the complete cytogenetic response (CCyR) rate of 35% (35/101) dasatinib vs 16% (8/49) im, suggesting that dasatinib can achieve deeper responses in this patient population. Of pts with no prior CyR to im, 44% (17/39) achieved a MCyR with dasatinib vs 7% (1/15) with higher dose im. MCyR rates of 40% to dasatinib and 20% to im were achieved in pts with baseline im-resistant BCR-ABL mutations, with 47% of dasatinib pts vs 0 im pts with difficult-to-treat P-loop mutations achieving a MCyR. Pts with no prior CyR to im were able to achieve MCyR with dasatinib, but dose escalation of im was not effective. 23% dasatinib pts vs 80% im pts had treatment failure (TF, defined as progression, lack of response, crossover for intolerance, or off treatment). Median time to TF was not reached for dasatinib, and was 3.5 mo (95% CI: 3.3-3.8) for im. 61 pts discontinued the initially assigned treatment, of whom 50 (12 dasatinib; 38 im) crossed over after progression, no response, or intolerance. Of 45 post-crossover pts (38 dasatinib; 7 im), 17 (45%) dasatinib pts achieved MCyR, but no (0%) im pts with 800mg/d achieved MCyR after crossover following dasatinib. Grade 3/4 non-hematologic toxicity was minimal in both arms. All grades of superficial edema and fluid retention were more common with im than dasatinib (41% im vs 15% dasatinib; and 43% im vs 28% dasatinib respectively), whereas pleural effusion was 13% (3% grade 3/4) dasatinib vs 0 im. Cytopenia was more frequent and severe with dasatinib. This is the first clinical trial in pts with CML to include both im and dasatinib arms. Based on nearly 1 year of follow-up, dasatinib clearly appears to be more effective in achieving MCyR than high-dose im in pts who fail 400–600mg/d im. An update with molecular response data and detailed mutational analysis will be presented.

Description: Point mutations were found in the adenosine triphosphate (ATP) binding region of BCR/ABL in 12 of 18 patients with chronic myeloid leukemia (CML) or Ph-positive acute lymphoblastic leukemia (Ph+ ALL) and imatinib resistance (defined as loss of established hematologic response), but they were found in only 1 of 10 patients with CML with imatinib refractoriness (failure to achieve cytogenetic response). In 10 of 10 patients for whom samples were available, the mutation was not detected before the initiation of imatinib therapy. Three mutations (T315I, Y253H, and F317L present in 3, 1, and 1 patients, respectively) have a predicted role in abrogating imatinib binding to BCR/ABL, whereas 3 other mutations (E255K, G250E, and M351T, present in 4, 2, and 2 patients, respectively) do not. Thus we confirm a high frequency of mutations clustered within the ATP-binding region of BCR/ABL in resistant patients. Screening may allow intervention before relapse by identifying emerging mutations with defined impacts on imatinib binding. Certain mutations may respond to higher doses of imatinib, whereas other mutations may mandate switching to another therapeutic strategy.

Description: Interpatient variability in intracellular uptake and retention (IUR) of imatinib may be due to variable function of the OCT-1 influx pump. OCT-1 activity was measured in pretherapy blood from chronic myeloid leukemia (CML) patients by calculating the difference in IUR of [14C]-imatinib with and without OCT-1 inhibition. Of patients with higher than median (high) OCT-1 activity, 85% achieved major molecular response (MMR) by 24 months, versus 45% with no more than a median (low) OCT-1 activity. Assessing patients receiving 600 mg imatinib per day and those averaging fewer than 600 mg over 12 months of therapy revealed patients with high OCT-1 activity achieved excellent molecular response regardless of dose, whereas response of patients with low OCT-1 activity was highly dose dependent. Of patients with low OCT-1 activity who received fewer than 600 mg, 45% failed to achieve a 2-log reduction by 12 months, and 82% failed to achieve a MMR by 18 months, compared with 8% and 17% in the cohort with high OCT-1 activity and dose less than 600 mg/day (P = .017 and P = .022). OCT-1 activity is an important determinant of molecular response to imatinib, with predictive value closely linked to dose. This pretherapy assay identifies patients at greatest risk of suboptimal response where dose intensity is critical, and those likely to respond equally well to standard dose imatinib.

Description: Imatinib-treated chronic myeloid leukemia (CML) patients with acquired resistance commonly have detectable BCR-ABL kinase domain mutations. It is unclear whether patients who remain sensitive to imatinib also have a significant incidence of mutations. We evaluated 144 patients treated with imatinib for BCR-ABL kinase domain mutations by direct sequencing of 40 accelerated phase (AP), 64 late chronic phase (≥ 12 months from diagnosis, late-CP), and 40 early-CP patients. Mutations were detected in 27 patients at 17 different residues, 13 (33%) of 40 in AP, 14 (22%) of 64 in late-CP, and 0 of 40 in early-CP. Acquired resistance was evident in 24 (89%) of 27 patients with mutations. Twelve (92%) of 13 patients with mutations in the adenosine triphosphate (ATP) binding loop (P-loop) died (median survival of 4.5 months after the mutation was detected). In contrast, only 3 (21%) of 14 patients with mutations outside the P-loop died (median follow-up of 11 months). As the detection of mutations was strongly associated with imatinib resistance, we analyzed features that predicted for their detection. Patients who commenced imatinib more than 4 years from diagnosis had a significantly higher incidence of mutations (18 [41%] of 44) compared with those treated within 4 years (9 [9%] of 100), P 〈 .0001. Lack of a major cytogenetic response (MCR) was also associated with a higher likelihood of detecting a mutation; 19 (38%) of 50 patients without a MCR had mutations compared with 8 (8.5%) of 94 with an MCR, P 〈 .0001. In conclusion, the detection of kinase domain mutations using a direct sequencing technique was almost always associated with imatinib resistance, and patients with mutations in the P-loop had a particularly poor prognosis. (Blood. 2003; 102:276-283)

Description: Fusion genes derived from the platelet-derived growth factor receptor beta (PDGFRB) or alpha (PDGFRA) play an important role in the pathogenesis of BCR-ABL–negative chronic myeloproliferative disorders (CMPDs). These fusion genes encode constitutively activated receptor tyrosine kinases that can be inhibited by imatinib. Twelve patients with BCR-ABL–negative CMPDs and reciprocal translocations involving PDGFRB received imatinib for a median of 47 months (range, 0.1-60 months). Eleven had prompt responses with normalization of peripheral-blood cell counts and disappearance of eosinophilia; 10 had complete resolution of cytogenetic abnormalities and decrease or disappearance of fusion transcripts as measured by reverse transcriptase–polymerase chain reaction (RT-PCR). Updates were sought from 8 further patients previously described in the literature; prompt responses were described in 7 and persist in 6. Our data show that durable hematologic and cytogenetic responses are achieved with imatinib in patients with PDGFRB fusion–positive, BCR-ABL–negative CMPDs.

Description: Abstract LBA-1 Background: Nilotinib is a highly potent and the most selective inhibitor of BCR-ABL, the only proven molecular target for CML therapy. ENESTnd (Evaluating Nilotinib Efficacy and Safety in Clinical Trials-Newly Diagnosed Patients) is a phase 3, randomized, open-label, multicenter study comparing the efficacy and safety of 300 or 400 mg bid nilotinib with 400 mg qd imatinib in patients (pts) with newly diagnosed Ph+ CML in chronic phase (CML-CP). Methods: 846 pts with newly diagnosed Ph+ CML-CP, diagnosed within 6 mos, and stratified by Sokal risk score, were randomized 1:1:1 to nilotinib 300 mg bid (n=282), nilotinib 400 mg bid (n=281), and imatinib 400 mg qd (n=283) arms. The primary endpoint was rate of major molecular response (MMR) at 12 months (mos). All pts had a minimum of 12 mos of treatment or discontinued early; median follow-up was 14 mos. MMR was defined as a value of ≤ 0.1% of BCR-ABL/ABL ratio on the International Scale. Molecular response was assessed by RQ-PCR at baseline, monthly for 3 mos and every 3 mos thereafter. Samples were analyzed at a central PCR laboratory. The major secondary endpoint was rate of complete cytogenetic response (CCyR) by 12 mos based on bone marrow cytogenetics. Results: Baseline demographics, disease characteristics, and Sokal scores were well balanced among the 3 arms; pts with high-risk Sokal scores were 28% in all arms. Median dose intensities of nilotinib delivered were 592 mg/day for 300 mg bid and 779 mg/day for 400 mg bid; imatinib dose intensity was 400 mg/day. Overall, 84%, 82%, and 79% of pts remained on the study for 300 mg bid nilotinib, 400 mg bid nilotinib, and 400 mg qd imatinib, respectively. Rates of MMR at 12 mos (Table) were superior for nilotinib 300 mg bid compared with imatinib 400 mg qd (44% vs. 22%,P 〈 .0001) and also for nilotinib 400 mg bid compared with imatinib 400 mg qd (43% vs. 22%,P 〈 .0001). Median time to MMR among pts who achieved MMR was faster for nilotinib 300 mg bid (5.7 mos) and nilotinib 400 mg bid (5.8 mos) compared with imatinib 400 mg qd (8.3 mos). Rates of CCyR by 12 mos were significantly higher for both nilotinib at either 300 mg bid compared with imatinib 400 mg qd (80% vs. 65%,P 〈 .0001) and for nilotinib 400 mg bid compared with imatinib 400 mg qd (78% vs. 65%,P = .0005). Overall, progression to advanced disease was lower for nilotinib 300 mg bid (2 pts) and nilotinib 400 mg bid (1 pt) compared with imatinib 400 mg qd (11 pts). Overall, both drugs were well-tolerated. Rates of discontinuation due to adverse events or laboratory abnormalities were 7% for nilotinib 300 mg bid, 11% for nilotinib 400 mg bid, and 9% for imatinib 400 mg qd. Pts were monitored for QT prolongation and LVEF. No patients in any treatment arm showed a QTcF interval 〉 500 msec. There was no decrease from baseline in mean LVEF anytime during treatment in any arm. The study is ongoing. Conclusions: Nilotinib at both 300 mg bid and 400 mg bid induced significantly higher and faster rates of MMR and CCyR compared with imatinib 400 mg qd, the current standard of care in pts with newly diagnosed CML. Nilotinib was effective across all Sokal scores. After only one year of treatment, both nilotinib arms resulted in a meaningful clinical benefit compared to imatinib, with reduction of transformation to AP/BC. Nilotinib exhibited a favorable safety and tolerability profile. The superior efficacy and favorable tolerability profile of nilotinib compared with imatinib suggests that nilotinib may become the standard of care in newly diagnosed CML. Disclosures: Saglio: Novartis: Consultancy, Speakers Bureau; BMS: Consultancy, Speakers Bureau. Off Label Use: Nilotinib is not currently approved for first-line treatment of CML. The presentation will report the results from a randomized study of imatinib versus nilotinib in patients with newly diagnosed Ph+ CML-CP. Kim:Novartis: Honoraria, Membership on an entity’s Board of Directors or advisory committees, Research Funding; BMS: Honoraria, Membership on an entity’s Board of Directors or advisory committees, Research Funding; Wyeth: Research Funding. le Coutre:Novartis: Honoraria, Research Funding; BMS: Honoraria. Reiffers:Novartis: Research Funding. Pasquini:Novartis: Consultancy, Membership on an entity’s Board of Directors or advisory committees; BMS: Membership on an entity’s Board of Directors or advisory committees; Schering: Membership on an entity’s Board of Directors or advisory committees. Clark:Novartis: Honoraria, Research Funding, Speakers Bureau. Hughes:Novartis: Honoraria, Research Funding; BMS: Honoraria, Research Funding. Hochhaus:Novartis: Research Funding. Gallagher:Novartis: Employment, Equity Ownership. Hoenekopp:Novartis: Employment. Dong:Novartis: Employment, Equity Ownership. Haque:Novartis: Employment. Larson:Novartis:

Description: Imatinib inhibits tyrosine kinases important in osteoclast (c-Fms) and osteoblast (platelet-derived growth factor receptor [PDGF-R], c-Abl) function, suggesting that long-term therapy may alter bone homeostasis. To investigate this question, we measured the trabecular bone volume (TBV) in iliac crest bone biopsies taken from chronic myeloid leukemia (CML) patients at diagnosis and again after 2 to 4 years of imatinib therapy. Half the patients (8 of 17) showed a substantive increase in TBV (〉 2-fold), after imatinib therapy, with the TBV in the posttreatment biopsy typically surpassing the normal upper limit for the patient's age group. Imatinib-treated patients exhibited reduced serum calcium and phosphate levels with hypophosphatemia evident in 53% (9 of 17) of patients. In vitro, imatinib suppressed osteoblast proliferation and stimulated osteogenic gene expression and mineralized-matrix production by inhibiting PDGF receptor function. In PDGF-stimulated cultures, imatinib dose-dependently inhibited activation of Akt and Crk-L. Using pharmacologic inhibitors, inhibition of PI3-kinase/Akt activation promoted mineral formation, suggesting a possible molecular mechanism for the imatinib-mediated increase in TBV in vivo. Further investigation is required to determine whether the increase in TBV associated with imatinib therapy may represent a novel therapeutic avenue for the treatment of diseases that are characterized by generalized bone loss.

Description: Pathological angiogenesis associated with wound healing often occurs subsequent to an inflammatory response that includes the secretion of cytokines such as tumor necrosis factor (TNF). Controversy exists on the angiogenic actions of TNF, with it being generally proangiogenic in vivo, but antiangiogenic in vitro. We find that whereas continuous administration of TNF in vitro or in vivo inhibits angiogenic sprouting, a 2- to 3-day pulse stimulates angiogenesis by inducing an endothelial “tip cell” phenotype. TNF induces the known tip cell genes platelet-derived growth factor B (PDGFB) and vascular endothelial cell growth factor receptor-2 (VEGFR2), while at the same time blocking signaling through VEGFR2, thus delaying the VEGF-driven angiogenic response. Notch signaling regulates tip cell function, and we find that TNF also induces the notch ligand jagged-1, through an NFκB-dependent mechanism. Enrichment of jagged-1 in tip cells was confirmed by immunofluorescent staining as well as by laser capture microdissection/quantitative reverse-transcription–polymerase chain reaction (qRT-PCR) of tip cells sprouting in vitro. Thus, in angiogenesis, the temporal expression of TNF is critical: it delays angiogenesis initially by blocking signaling through VEGFR2, but in addition by inducing a tip cell phenotype through an NFκB-dependent pathway, it concomitantly primes endothelial cells (ECs) for sprouting once the initial inflammatory wave has passed.

Description: While transplantation of unrelated umbilical cord blood (UCB) halts the progression of neurological damage in children with lysosomal storage diseases (LSD), it does not necessarily reverse the damage sustained before transplant. Isolation and expansion of central nervous system progenitor cells from UCB has potential therapeutic application in treating these patients. We have recently described the reliable isolation and expansion of oligodendrocyte-like precursor cells (OPC) from freshly collected, non-crypreserved UCB (Tracy et al. Cytotherapy. 2008, 3:1–8). We anticipate utilizing these cells as adjuvant, targeted therapy to reduce the time to donor cell correction/prevention of disease-induced CNS injury. This approach will require use of cyropreserved donor UCB. We now demonstrate the feasibility of isolating and expanding OPCs from a series of thawed, cryopreserved UCB units and comparing those cells to OPCs derived from fresh UCB units. Cryopreserved UCB units were thawed using a standard protocol employed in clinical transplantation. Mononuclear cells were isolated by either ficoll density separation or centrifugation after a dextran-albumin wash. Fresh UCB units underwent hetastarch depletion of red blood cells then mononuclear cell isolation by ficoll density gradient separation. Both types of cells were plated at 3×10(6) cells/ml in media containing platelet derived growth factor, neurotopin 3, vascular endothelial growth factor, and triiodothyronine. All UCB unit cultures were trypsinized at 21 days, counted, then characterize by flow cytometry after being fixed, permeablized, and labeled with the following antibodies: anti-oligidendrocyte marker 4 (O4), anti-oligidendrocyte marker 1 (O1), anti-myelin basic protein (MBP). To examine phenotypic changes over time, cultures from two units (one thawed, one fresh) were also analyzed weekly over 4 weeks. On flow cytometric analysis, 72% of thawed UCB units yielded O4-expressing cells as at least 20% of total events compared with 94% of fresh UCB units (Table 1). Average oligodendrocyte yield per UCB unit was less for thawed units (9.65×10(5)) compared with fresh (3.77×10(6)). However, within the gated population, expression of O1, O4, and MBP was similar between thawed and fresh cords. We also noted early expression of the preoligodendrocyte marker O4 by 1–2 weeks in culture, followed by increasing expression of mature oligodendrocyte markers O1 and MBP over the subsequent 2–4 weeks (Table 2). Our results demonstrate that oligodendrocyte precursor cells can be derived reliably from thawed, cryopreserved UCB units, and suggest the feasibility of using these cells in human clinical trials. Table 1: Characteristics of UCB-Derived Oligodendrocytes Thawed UCB Units Fresh UCB Units Total Units Cultured 18 16 Mean # mononuclear cells plated/UCB Unit 2.55×10(8) 1.4×10(8) Final oligodendrocyte cell count/UCB Unit 8.41×10(5) 3.7×10(6) Units with O4 expression 〉20% of total events 13 (72%) 15 (94%) Events in gate as % total events 58.26 77.83 O4 expression (% of gated) 83.66 86.45 O1 expression (% of gated) 88.13 86.29 MBP expression (% of gated) 31.10 31.41 Co-expression of MBP-O1 (% of gated) 28.50 31.86 Table 2: Expression of Markers by UCB-Derived Oligodendrocytes Thawed UCB Unit Fresh UCB Unit Day O1 MBP MBP+ O1 Day O1 MBP MBP+ O1 Day 7 95.75 10.14 9.45 Day 7 68.78 25.13 12.11 Day 14 98.07 35.93 35.74 Day 14 97.71 34.03 33.75 Day 21 95.24 35.43 31.80 Day 21 99.22 34.82 34.72 Day 28 99.69 51.08 51.04 Day 28 96.49 24.10 23.40