International myeloma working group (IMWG) consensus statement and guidelines regarding the current status of stem cell collection and high-dose therapy for multiple myeloma and the role of plerixafor (AMD 3100)

Multiple myeloma is the most common indication for high-dose chemotherapy with autologous stem cell support (ASCT) in North America today. Stem cell procurement for ASCT has most commonly been performed with stem cell mobilization using colony-stimulating factors with or without prior chemotherapy. The target CD34+ cell dose to be collected as well as the number of apheresis performed varies throughout the country, but a minimum of 2 million CD34+ cells/kg has been traditionally used for the support of one cycle of high-dose therapy. With the advent of plerixafor (AMD3100) (a novel stem cell mobilization agent), it is pertinent to review the current status of stem cell mobilization for myeloma as well as the role of autologous stem cell transplantation in this disease. On June 1, 2008, a panel of experts was convened by the International Myeloma Foundation to address issues regarding stem cell mobilization and autologous transplantation in myeloma in the context of new therapies. The panel was asked to discuss a variety of issues regarding stem cell collection and transplantation in myeloma especially with the arrival of plerixafor. Herein, is a summary of their deliberations and conclusions.

Final results of PX-171–003-A0, part 1 of an open-label, single-arm, phase II study of carfilzomib (CFZ) in patients (pts) with relapsed and refractory multiple myeloma (MM)

8504

Background: CFZ is a novel proteasome inhibitor of the epoxyketone class that exhibits a high level of proteasome selectivityand demonstrates antitumor activity in bortezomib (BTZ)-resistant MM pts in phase I studies. Methods: PX-171–003-A0 was an open-label, multicenter study that enrolled MM pts who relapsed from >2 prior therapies, failed BTZ and at least 1 immunomodulatory agent [thalidomide (THAL) or lenalidomide (LEN)], and were refractory to last treatment [progressing on or within 60 d of last therapy or <25% response to last therapy]. Pts received CFZ 20 mg/m2 IV d 1, 2, 8, 9, 15 and 16 every 28 d for up to 12 cycles (C). Clinical benefit response (CBR) was defined as MR or better. Results: 46 pts were enrolled, including 78% with progression on or within 60 d of last therapy and 22% with no response to last therapy. 39 pts completed at least 1 C of CFZ, had measurable M-protein, and were evaluable for response. Median prior therapies was 5 (range 2–15). 100% of pts received prior BTZ, 91% prior THAL, 89% prior LEN, and 83% prior stem cell transplant (SCT) and all had failed combinations including anthracyclines (80%) and/or alkylating agents (94%). Pts received a median of 3 C (range 1–12); 13 pts completed ≥6 C. CBR was 26% (10/39 eval pts), including 5 pts achieving PR and 5 pts achieving MR. 5 BTZ-refractory pts achieved MR or PR. Median TTP was 6.2 mo, the median DOR for the MR + PR was 7.4 mo. 8/10 pts achieved response during C1. 16 additional pts achieved SD for at least 6 wks. The most common adverse events were fatigue, anemia, thrombocytopenia, nausea, upper respiratory infection, increased creatinine and diarrhea. Peripheral neuropathy occured in < 10% of pts with 1 Gr 3 in a pt with pre-existing Gr 2. Conclusions: Single-agent CFZ achieved a TTP of > 6 mo in relapsed and refractory MM pts who failed available therapies. 26% of patients had at least an MR and median duration of >7 mo with this steroid- and anthracycline-sparing regimen. CFZ toxicities were manageable and importantly, exacerbation of pre-existing PN was rare. The study has been expanded to enroll an additional 250 pts in this unmet medical need population at an escalated dose, and treatment has been extended beyond a year.

[Table: see text]

Lenalidomide, bortezomib, and dexamethasone in relapsed/refractory multiple myeloma (MM): Encouraging outcomes and tolerability in a phase II study

8536

Background: Lenalidomide (Revlimid, Len), bortezomib (VELCADE, Bz; maximum tolerated dose [MTD] 15 mg/1.0 mg/m2) ± dexamethasone (Dex; 20–40 mg; RVD) was well tolerated in a phase I study in relapsed/refractory MM patients (pts), with 58% ≥MR. This multicenter phase 2 study evaluated RVD efficacy and safety at the MTD. Methods: Patients received up to eight 21-day cycles of Len 15 mg (days 1–14), Bz 1.0 mg/m2 (days 1, 4, 8, 11), and Dex 40/20 mg (cycles 1–4/5–8, days of/after Bz dosing). After cycle 8, patients with stable/responding disease received maintenance (Len, days 1–14; Bz, days 1, 8; doses per end of cycle 8; Dex 10 mg, days 1, 2, 8, 9) until progression or unacceptable toxicity. Pts with significant peripheral neuropathy were excluded. Results: Among 64 pts, 38 (59%) had relapsed and 26 (41%) refractory/relapsed MM. Median number of prior therapies was two, including Len (8%), Bz (55%), Dex (92%), thalidomide (77%), and stem cell transplant (SCT, 36%). Forty-one pts (64%) completed 8 cycles, 33 continue on maintenance, 22 discontinued early (11 due to progressive disease). Toxicities were manageable, primarily grade (G) 1/2 myelosuppression; 2 developed DVT on aspirin, 2 G3 atrial fibrillation, 1 G3 peripheral neuropathy. One pt died on-study (fungal pneumonia, possibly due to Dex). Overall response rate (62 evaluable patients) was 84% ≥MR, including 21% CR/nCR, 68% ≥PR, which was independent of high-risk features and prior treatment ( Table ). Median duration of response is 24 weeks (range 6–81). Time-to-events data including median time to progression, progression-free survival, and 1-year survival rates will be presented. Conclusions: RVD is active and well tolerated in pts with relapsed/refractory MM, including pts who have received prior Len, Bz, thalidomide, and SCT. Durable responses have been observed and appear independent of adverse cytogenetics and other recognized risk factors.

[Table: see text]

[Table: see text]

PX-171–004, a multicenter phase II study of carfilzomib (CFZ) in patients with relapsed myeloma: An efficacy update

8537

Background: Carfilzomib (CFZ) is a proteasome inhibitor, active against hematologic malignancies. Preclinically, CFZ overcomes bortezomib (BTZ) resistance in multiple tumors, including myeloma (MM). PX-171–004 is an ongoing Phase II study evaluating safety and efficacy of CFZ in MM patients with relapsed disease after 1–3 prior therapies. Overall Response Rate (ORR) of 35.5% for all subjects was previously reported (ASH 2008); updated data are now available. Methods: Patients were divided into two cohorts: BTZ-naïve and BTZ-exposed. CFZ 20 mg/m2 was administered Days 1, 2, 8, 9, 15 and 16 in a 28-day cycle, for up to 12 cycles. Dexamethasone 4 mg po was administered prior to each dose in Cycle 1. The primary endpoint was ORR, defined as Partial Response (PR) or better. Secondary endpoints included Duration Of Response (DOR) and Time To Progression (TTP). Results: 31 patients were enrolled; 14 (45%) BTZ-naïve and 17 (55%) BTZ-exposed. Of the BTZ-exposed cohort, 2 subjects received BTZ exclusively as a single agent, 6 had BTZ in a chemotherapy combination, and 9 received BTZ in a transplant regime. Overall, 23 (74%) subjects had > 1 prior therapy and 27 (87%) received transplant. In BTZ-naïve patients, CFZ achieved an ORR of 57%; median DOR of 8.6 mos (range >1.9 to >9.7 mos). To date, 7 patients (50%) remain progression free and 3 patients have completed 12 cycles. The median follow-up was 10 mos and the median TTP has not been reached. For the BTZ- exposed group, CFZ achieved an ORR of 18%; median DOR not yet reached (>8.5 mos) (range >1 d to >8.5 mos). 7 patients (41%) are progression free and 3 patients have completed 12 cycles. Median follow-up and TTP were 9.2 and 8.9 mos, respectively. Conclusions: These preliminary results demonstrate that single-agent CFZ is tolerable for at least 1 yr and achieves sustained responses in relapsed MM. Prior BTZ mono/combination therapy does not preclude durable response with CFZ. These data support continuing evaluation of CFZ in the treatment of relapsed MM.

[Table: see text]

[Table: see text]

A phase II multicenter study of CNTO 328, an anti-IL-6 monoclonal antibody, in patients (pts) with relapsed or refractory multiple myeloma (MM)

8527

Background: Relapsed/refractory MM constitutes a specific and unmet medical need with poor overall response and survival. Interleukin-6 (IL-6) plays an important role in MM cell proliferation, survival, and corticosteroid resistance and previous studies have shown clinical benefit from anti-IL-6 therapy. We therefore evaluated the combination of CNTO328, a chimeric monoclonal antibody with high affinity for human IL-6, and dexamethasone (dex) in pts with relapsed/refractory MM. Methods: Pts were treated with 6 mg/kg CNTO328 IV Q2 weeks. Oral dex (40mg) was given once daily, days 1–4, 9–12, and 17–20 for a max of 4 cycles; and on days 1–4 for subsequent cycles. Inclusion criteria were > 2 prior lines of systemic therapy, creatinine clearance >20 ml/min, platelets >50,000/mm3, and neutrophils >1000/mm3. Primary endpoint was overall response with secondary endpoints of time to progression, incidence of AEs and SAEs. Results: Thirty-nine pts received at least 1 infusion of CNTO328 in combination with dex - median age 66 yrs (range 43–89), median disease duration 4.2 yrs (1–13), median lines of prior therapy 5 (2–9) including bortezomib (100%), IMIDs (87%), and ASCT (59%). The median duration of therapy was 3.3 months (0.5–21+). Of the 36 pts who were evaluable, the overall response rate (CR+PR+MR) using EBMT criteria was 31% (7PR, 4MR). An additional 4 uMR and 4 SD lasting ≥3 months have been reported. PRs were durable; 6 out of 7 pts had responses ranging from 3 months to up to more than 1 year (with 1 still ongoing for more than 1 year). Duration of MRs ranged from 2–5 months. Responses were seen in pts relapsing after and refractory to at least one other prior treatment including bortezomib, IMIDs, or steroids. Median time to disease progression (PD) was 3.7 months (0.3–18+). Main reasons for treatment discontinuation were PD (24) and AEs (6). Hematologic toxicities Grade ≥ 3 were common though not dose-limiting. Three pts had Grade ≥ 3 infections considered reasonably related to CNTO328. Conclusions: CNTO 328 in combination with dex shows promising preliminary activity in this heavily pretreated patient population with an acceptable safety profile. Further investigation is ongoing.

No significant financial relationships to disclose.

Endoscopic ultrasound and fine needle aspiration for the diagnosis of hepatocellular carcinoma

Liver cancer is one of the most frequent solid cancers. The major risk factor associated with the development of hepatocellular carcinoma (HCC) is cirrhosis caused by hepatitis B, hepatitis C virus or chronic alcohol consumption. The overall prognosis of patients with HCC is very poor and this is mainly due to the advanced stages of cancer at presentation and also because of underlying cirrhosis. When HCC is diagnosed at early stages, prognosis is better with five-year disease free survival of around 50% with resection, or local ablative treatments such as radio-frequency ablation or percutaneous ethanol injection, and 70-80% with liver transplantation. Therefore, systematic screening of all the high-risk patients is the key to an early diagnosis of small HCC and the use of an appropriate treatment modality. The currently available tools for the screening, surveillance and diagnosis of HCC in the presence of cirrhosis remain sub-optimal. The advancements made in the past 10 years, however, have made HCC a potentially curable disease in a highly selected group of patients. This review will briefly discuss the current guidelines for surveillance and diagnosis of HCC in high-risk subjects and then review the potential role of endoscopic ultrasound and fine needle aspiration for the diagnosis of small HCC.

The effect of induction therapy with novel agents on stem cell mobilization in multiple myeloma

8102

Background: Thalidomide or bortezomib combined with dexamethasone (TD or BD respectively) are now being increasingly used as induction regimens for newly diagnosed multiple myeloma. There are conflicting reports on the effects of T on stem cell mobilization. Since we have used both these regimens at our center, we performed a retrospective analysis of stem cell mobilization after induction therapy with either TD (n = 22) or BD (n = 18). Methods: The patients were balanced with respect to initial Durie-Salmon stage, median number of cycles of induction therapy prior to collection, response to induction therapy, bone marrow cellularity and involvement, and time from end of therapy to collection. All patients were mobilized with G-CSF 10mcg/kg and collected in a large volume pheresis, with a goal of at least 6x10(6) CD34+ cells/kg (for tandem transplant). Results: To achieve our stem cell goal, the number of patients who required 3 or more phereses in the TD group was 17/22 whereas it was only 4/18 in the BD group. (p<0.005). 3/3 patients who had received lenalidomide also required 3 or more phereses. Also, the number of CD34+ cells/kg obtained in the TD group was less–mean of 2.8x10(6) per pheresis, as compared to a mean of 5.2x10(6) per pheresis in the BD group (p<0.01). Time to neutrophil engraftment was similar in both groups. However in the TD group there was a 1 day delay in platelets > 20,000/ul (p<0.05). Conclusions: Thus, thalidomide induction led to a lower yield of stem cells when compared to bortezomib. Differences in stem cell markers are being investigated. This may become especially important when limiting numbers of stem cells are available from elderly patients, those with prior radiation or bulk disease and when used for in vitro manipulation. It is possible that agents such as bortezomib may alter the bone marrow microenviroment differently from imids such as thalidomide.

No significant financial relationships to disclose.

Predicting and monitoring tumor response to epidermal growth factor receptor inhibitor gefitinib in patients with locally advanced esophageal adenocarcinoma

14112

Background: This study aimed to validate an ex vivo chemosensitivity assay to measure the pharmacodynamic effect of gefitinib on esophageal adenocarcinoma (EAC) prior to treatment with pre-operative concomitant chemoradiotherapy (CRT). Methods: A 14 day run-in period with 250 mg/day of gefitinib preceded CRT. Endoscopic biopsies (D 0 and 14) in 4 patients with T2–3N0/1M0/1a EAC were analyzed by ex vivo chemosensitivity assay. Day 0 tissue was exposed to gefitinib ex vivo, then tumor was exposed to gefitinib for 14 days in vivo (ie in the patient). Phosphorylation of the EGFR, raf/MEK/ERK and PI3/AKT pathways was measured by Western blot. Profiles were compared for correlation between ex vivo and in vivo exposure, and patterns were correlated with response to CRT. The effects were also characterized by immunohistochemistry (IHC). EGFR, K-Ras, and PI3K mutations, serum concentrations of gefitinib and PTEN status were measured as potential confounders. Results: One patient with stage T3N1 died of unexplained hemorrhage during surgery. Three had clinical and path stages of: T3N1/T0N0, T3N0/T3N0, T3N1/T2N1. Gefitinib levels were constant, confirming exposure of target tissue to the drug. Ex vivo exposure yielded four distinct pathway patterns. The exact same patterns were seen after in vivo exposure. No mutations were identified in exons 18–21 of the EGFR, exons 2/3 of K-ras or exons 9/22 of PI3K. PTEN levels were similar in all tumors. PCNA expression correlated with raf/MEK/ERK pathway inhibition, but not with inhibition of EGFR activity. IHC correlated with Western blot for expression of EGFR, and phospho- and total ERK levels. No correlation was observed between gefitinib effect and pathologic response to CRT. Conclusions: This study used a novel ex vivo chemosensitivity assay to demonstrate the activity of gefitinib to inhibit target in tumor tissue obtained from patients with EAC. The exact correlation of pre- and post-treatment profiles suggests potential use in the pre-treatment setting to predict in vivo effects of targeted therapies. This approach may facilitate the further refinement of patient selection to maximize potential benefit while sparing patients unlikely to respond to a given agent.

No significant financial relationships to disclose.

Bortezomib appears to overcome the poor prognosis conferred by chromosome 13 deletion in phase 2 and 3 trials

In multiple myeloma, deletion of chromosome 13 (del(13)) is associated with poor prognosis regardless of treatment. This study analyzed the impact of del(13) status on response and survival following treatment with either bortezomib or high-dose dexamethasone in patients in the SUMMIT and APEX trials. Additionally, matched-pairs subset analyses were conducted of patients with and without del(13), balanced for age and International Staging System parameters. In both SUMMIT and APEX, prognosis appeared to be poorer in bortezomib-treated patients with del(13) compared with patients with no del(13) by metaphase cytogenetics. In the SUMMIT and APEX matched-pairs analysis, response and survival appeared comparable in bortezomib-treated patients with or without del(13) by metaphase cytogenetics. However, patients with del(13) receiving dexamethasone in APEX appeared to have markedly decreased survival compared with those without del(13) by metaphase cytogenetics. These matched-pairs analyses suggest that bortezomib may overcome some of the poor impact of del(13) as an independent prognostic factor. However, sample sizes were very small; these findings require confirmation from further studies.

Tumor antigen immunization of sibling stem cell transplant donors in multiple myeloma

The unique antigenic determinants (idiotype (Id)) of the immunoglobulin secreted by myeloma tumor can serve as a tumor-specific antigen for active immunotherapy. Our objective was to induce tumor-specific T-cell immunity in bone marrow transplant (BMT) donors to enhance antitumor effects of allografts. We vaccinated five HLA-matched sibling donors with myeloma Id proteins isolated from recipient plasma before bone marrow harvest. Recipients were administered booster Id immunizations following transplantation. Vaccination induced donor Id and carrier-specific cellular and/or humoral immune responses. Two recipients died within 30 days of BMT from transplant-related complications. Id and carrier-specific T-cell responses were detected in all three remaining patients post-, but not pre-BMT and persisted for 18 months. All three surviving patients converted from partial to complete responses following BMT. Two of the three patients remain disease-free 7 years and 8 years after BMT, and the third died of renal failure after 5.5 years while in complete remission from myeloma. Our results suggest that myeloma Id vaccination induces specific T-cell immunity in healthy donors which may be transferable by BMT, is associated with prolonged disease-free survival of recipients, and may represent a general strategy to enhance graft-versus-tumor effect in other malignancies for which defined tumor-specific antigens exist.