Efficacy and safety of ofatumumab and bendamustine followed by ofatumumab maintenance in patients with relapsed indolent non-Hodgkin lymphoma after prior rituximab

In indolent non-Hodgkin's lymphoma (iNHL), patients treated with rituximab, alone or in combination with various chemotherapeutic agents eventually relapse. This study evaluated the combination of ofatumumab and bendamustine, followed by maintenance ofatumumab in patients with relapsed iNHL with prior sensitivity to rituximab. Among the 49 patients enrolled, 24.5% achieved a complete response (CR) and 42.9% achieved a partial response (PR), with an overall response rate of 67.3% at the end of the induction therapy. Additionally, six patients with PR during induction phase achieved CR during the maintenance phase. Treatment-related adverse event was observed in 95.9% patients. The most common hematologic and biochemical abnormalities were decrease in lymphocytes (85.7%) and increase in glucose (91.8%), respectively. Overall, 42.9% progressed and 14.3% died during the study. Thus, ofatumumab in combination with bendamustine, followed by ofatumumab maintenance, was effective in the treatment of patients with iNHL with a manageable safety profile (NCT01294579).

A Phase Ib multicenter, dose-escalation study of the polyamine analogue PG-11047 in combination with gemcitabine, docetaxel, bevacizumab, erlotinib, cisplatin, 5-fluorouracil, or sunitinib in patients with advanced solid tumors or lymphoma

PURPOSE

Polyamines are absolutely essential for maintaining tumor cell proliferation. PG-11047, a polyamine analogue, is a nonfunctional competitor of the natural polyamine spermine that has demonstrated anticancer activity in cells and animal models of multiple cancer types. Preclinical investigations into the effects of common chemotherapeutic agents have revealed overlap with components of the polyamine metabolic pathway also affected by PG-11047. This report describes a Phase Ib clinical trial investigating PG-11047 in combination with cytotoxic and anti-angiogenic chemotherapeutic agents in patients with advanced refractory metastatic solid tumors or lymphoma.

METHODS

A total of 172 patients were assigned to treatment arms based on cancer type to receive the appropriate standard-of-care therapy (gemcitabine, docetaxel, bevacizumab, erlotinib, cisplatin, 5-fluorouracil (5-FU), or sunitinib as directed) along with once weekly intravenous infusions of PG-11047. PG-11047 dose escalation ranged from 50 to 590 mg.

RESULTS

The maximum tolerated dose (MTD) of PG-11047 in combination with bevacizumab, erlotinib, cisplatin, and 5-FU was 590 mg. Dose-limiting toxicities (DLTs) in these groups were rare (5 of 148 patients). Overall partial responses (PR) were observed in 12% of patients treated with PG-11047 and bevacizumab, with stable disease documented in an additional 40%. Stable disease occurred in 71.4% of patients in the 5-FU arm, 54.1% in the cisplatin arm, and 33.3% in the erlotinib arm. Four of the patients receiving cisplatin + PG-11047 (20%) had unconfirmed PRs. MTDs for gemcitabine, docetaxel, and sunitinib could not be determined due to DLTs at low doses of PG-11047 and small sample size.

CONCLUSIONS

Results of this Phase Ib trial indicate that PG-11047 can be safely administered to patients in combination with bevacizumab, erlotinib, cisplatin, and 5-FU on the once weekly dosing schedule described and may provide therapeutic benefit. The manageable toxicity profile and high MTD determination provide a safety profile for further clinical studies.

CC-486 (oral azacitidine) in patients with myelodysplastic syndromes with pretreatment thrombocytopenia

Thrombocytopenia is among the strongest predictors of decreased survival for patients with myelodysplastic syndromes (MDS) across all prognostic risk groups. The safety and efficacy of CC-486 (oral azacitidine) was investigated in early-phase studies; we assessed clinical outcomes among subgroups of MDS patients from these studies, defined by presence or lack of pretreatment thrombocytopenia (≤75 × 10⁹/L platelet count). Patients received CC-486 300 mg once-daily for 14 or 21 days of repeated 28-day cycles. Overall, 81 patients with MDS, median age 72 years, comprised the Low Platelets (n = 45) and High Platelets (n = 36) cohorts. Pretreatment median platelet counts were 34 × 10⁹/L and 198 × 10⁹/L, respectively. Grade 3-4 bleeding events occurred in 2 patients in the Low Platelets and 1 patient in the High Platelets groups; events resolved without sequelae. Treatment-related mortality was reported for 7 patients, 5 of whom had pretreatment platelet values <25 × 10⁹/L. Overall response rates were 38% and 46% in the Low Platelets and High Platelets groups, respectively. Five thrombocytopenic patients attained complete remission and 9 attained platelet hematologic improvement. In both cohorts, platelet counts dropped during the first CC-486 treatment cycle, then increased thereafter. Extended CC-486 dosing was generally well tolerated and induced hematologic responses in these patients regardless of pretreatment thrombocytopenia.

Sotatercept with long-term extension for the treatment of anaemia in patients with lower-risk myelodysplastic syndromes: a phase 2, dose-ranging trial

BACKGROUND

Myelodysplastic syndromes are characterised by ineffective erythropoiesis leading to anaemia. Sotatercept (ACE-011) is a novel activin receptor type IIA fusion protein that acts as a ligand trap to neutralise negative regulators of late-stage erythropoiesis. The aim of the study was to establish a safe and effective dose of sotatercept for the treatment of anaemia in patients with lower-risk myelodysplastic syndromes.

METHODS

This open-label, multicentre, dose-ranging, phase 2 trial took place at 11 treatment centres in the USA and France. Eligible patients were aged 18 years or older, had International Prognostic Scoring System-defined low-risk or intermediate-1-risk myelodysplastic syndromes, had anaemia requiring red blood cell (RBC) transfusions, and were ineligible for, or refractory to, erythropoiesis-stimulating agents (ESAs). Patients were not eligible if they had chromosome 5q deletion myelodysplastic syndromes without documented failure of lenalidomide. Patients were randomly assigned to receive either 0·1 or 0·3 mg/kg sotatercept subcutaneously, using a permuted-block method with stratification for serum erythropoietin concentration and transfusion burden. Patients were assigned to 0·5, 1·0, and 2·0 mg/kg groups in a non-randomised fashion. The primary efficacy endpoint was the proportion of patients who achieved haematological improvement-erythroid (HI-E), according to International Working Group 2006 criteria. Efficacy and safety analyses were done in the intention-to-treat population. This trial is registered at ClinicalTrials.gov, number NCT01736683 and at EU Clinical Trials Register, number 2012-002601-22, and is ongoing.

FINDINGS

Between Dec 5, 2012, and July 22, 2015, 74 patients were enrolled into the study (seven to receive 0·1 mg/kg sotatercept, six to 0·3 mg/kg, 21 to 0·5 mg/kg, 35 to 1·0 mg/kg, and five to 2·0 mg/kg). 36 (49%; 95% CI 38-60) of 74 patients achieved HI-E; 29 (47%; 95% CI 35-59) of 62 patients with a high transfusion burden achieved HI-E (RBC-transfusion reduction from baseline of 4 or more units for at least 56 days), and seven (58%; 95% CI 32-81) of 12 patients with a low transfusion burden achieved HI-E (haemoglobin increase of 1·5 g/dL or more sustained for at least 56 days in the absence of transfusions). The most commonly reported adverse events were fatigue in 19 (26%) of 74 patients and peripheral oedema in 18 (24%) of 74 patients. Grade 3-4 treatment-emergent adverse events (TEAEs) were reported in 25 (34%) of 74 patients; four (5%) patients had grade 3-4 TEAEs that were considered to be treatment related. The most common grade 3-4 TEAEs were lipase increase and anaemia, which each occurred in three (4%) of 74 patients. 17 (23%) of 74 patients had at least one serious TEAE, and one patient died from a treatment-emergent subdural haematoma due to a fall.

INTERPRETATION

Sotatercept, a novel activin-receptor fusion protein, was well tolerated and effective for the treatment of anaemia in patients with lower-risk myelodysplastic syndromes in whom previous ESA treatment had failed. Treatment with sotatercept could be beneficial for these patients who have few available treatment options.

FUNDING

Celgene Corporation.

Antitumor activity and safety of combination therapy with the Toll-like receptor 9 agonist IMO-2055, erlotinib, and bevacizumab in advanced or metastatic non-small cell lung cancer patients who have progressed following chemotherapy

BACKGROUND

IMO-2055 is a Toll-like receptor 9 (TLR9) agonist that potentially enhances the efficacy of antitumor agents through immune stimulation. The objective of this phase Ib dose-escalation trial (3 + 3 design) was to determine the recommended phase II dose (RP2D) of IMO-2055 when combined with erlotinib and bevacizumab in patients with advanced non-small cell lung cancer (NSCLC).

METHODS

Patients with stage 3/4 NSCLC and progressive disease (PD) following chemotherapy received IMO-2055 0.08, 0.16, 0.32, or 0.48 mg/kg once weekly plus erlotinib 150 mg daily and bevacizumab 15 mg/kg every 3 weeks. Patients could receive treatment until PD or unacceptable toxicity.

RESULTS

Thirty-six patients were enrolled; 35 received at least one treatment dose. Two dose-limiting toxicities were observed across the dose range (Grade 3 dehydration and fatigue) with neither suggestive of a consistent toxicity pattern. IMO-2055 0.32 mg/kg was adopted as RP2D based on clinical and pharmacodynamic data. The most common treatment-emergent adverse events (TEAEs) were diarrhea (74 %), nausea (51 %), fatigue (51 %), rash (51 %), and injection-site reactions (49 %). Four patients experienced serious TEAEs considered to be study drug related. Five patients died, all due to PD. High-grade neutropenia and electrolyte disturbances previously reported with TLR9 agonists combined with platinum-based therapy were not observed in this study. Five of 33 patients evaluable for response (15 %) achieved partial response; another 20 (61 %) had stable disease, including 13 with stable disease ≥4 months.

CONCLUSIONS

IMO-2055 demonstrated good tolerability and possible antitumor activity in combination with erlotinib and bevacizumab in heavily pretreated patients with advanced NSCLC.

Randomized phase II trial of preoperative chemoradiotherapy with or without cetuximab in locally advanced rectal adenocarcinoma

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Background: Treatment for locally advanced rectal cancer (LARC) includes preoperative radiation concurrent with fluoropyrimidine chemotherapy (CRT). Local recurrence is a problem. Cetuximab is active in colorectal cancer and is effective with radiotherapy in other diseases. This study evaluated the pathologic response rate for LARC treated with preoperative chemoradiotherapy w/wo cetuximab. Methods: LARC (T3/4 or LN+, M0) pts were randomized to Arm1/Arm2. Arm 1 received standard pelvic radiotherapy (5040-5400cGy in daily fractions) with continuous infusional 5-FU (225mg/m2/day); Arm 2 received identical chemoradiotherapy + concurrent cetuximab (400mg/m2 initial dose) 1 week before pelvic radiotherapy, followed by 250mg/m2 weekly for the duration of chemoradiotherapy. After study treatment completion, pts were re-evaluated clinically and radiographically for clinical response. After 6-8 weeks, patients underwent surgical resection. The primary end point was pathologic CR (pCR), and secondary endpoints included ORR, RFS, OS, and local recurrence rates. Results: 139 pts were enrolled (Arm 1=69/Arm2=70); Arm1/Arm2 median age 61/55 yrs, and stage II and III 59%, 39%/40%, 60%. In 124 postsurgery pts, pCR occurred in 17 Arm 1 pts (28.3%, 95% CI 17.5-41.4) and 17 Arm 2 pts (26.6%, 95% CI 16.3-39.1); TRG postsurgery was similar between treatment arms (Table). Grade 3 and 4 toxicities were largely nonhematologic: diarrhea 16%/22%, rash 0%/12%, dehydration 5%/8%, mucositis 5%/6%. The 5-yr RFS for Arm1/Arm2 was 61%/65%, 5-yr OS was 66%/83%, local recurrence was 3%/4%. Conclusions: The addition of cetuximab to preoperative CRT for LARC was associated with increased but manageable toxicities. pCR rates were similar between treatment arms, as were survival statistics and local recurrence rates. No association was found between KRAS status and pCR. Clinical trial information: NCT00527111. [Table: see text]

Tolerability and activity of combinations of the PI3Kδ inhibitor idelalisib (GS-1101) with rituximab and/or bendamustine in patients with previously treated, indolent non-Hodgkin lymphoma (iNHL): Updated results from a phase I study

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Background: PI3K-delta signaling is critical for activation, proliferation and survival of B cells, and is hyperactive in many B-cell malignancies. Idelalisib is a first-in-class, selective, oral inhibitor of PI3Kδ that has shown considerable monotherapy activity in recurrent iNHL (Kahl, ICML 2011), as well as combination therapy (Fowler, ASCO 2012). Methods: This phase I study evaluated the activity of continuous (48 weeks) idelalisib (Id), 100/150 mg BID, in combination with rituximab (R) (375 mg/m2 weekly x 8 doses) (Id+R), with bendamustine (B) (90 mg/m2 x 2, for 6 cycles) (Id+B), or in combination with R (375 mg/m2 monthly x 6) and B (90 mg/m2 x 2), for 6 cycles (Id+BR). Investigators assessed response according to standard criteria (Cheson 2007). Patients who continued to benefit were able to enroll on an extension study. Results: Study enrolled 78 pts with relapsed/refractory iNHL, with 34 (44%) pts continuing on treatment in the ongoing extension protocol. The 3 cohorts included Id+R (N=30), Id+B (N=34), and Id+BR (N=14). Pts were 67% male, median age [range] of 62 [37E84] years, 41% with refractory disease, 88% stage III/IV, and 36% of FL with high FLIPI scores. The median [range] number of prior therapies was 3 [1E10]. The median [range] duration of treatment was 10.6 [0.5-29.2] months. Overall response rate (ORR) was 63/78 (81%), with 22/78 (28%) CR. The ORR/CR for Id+R was 77%/20%, Id+B was 85%/29%, and Id+BR was 79%/43%. At 20 months, the PFS was 66%. For responders, 73% were progression-free at 20 months. Most common adverse events included (total%/≥G3%) pyrexia (56/4), fatigue (45/4), nausea (41/0), rash (40/8), cough (37/0), diarrhea (36/8), chills (18/0), URI (18/1), and pneumonia (17/15). Lab abnormalities included (total%/≥G3%) ALT/AST elevations (56/17). Conclusions: Idelalisib-based combination therapy is highly active and well tolerated in patients with relapsed/refractory iNHL. These data support further clinical development. Phase III trials evaluating the efficacy of idelalisib in combination with R, or BR in iNHL are ongoing (NCT01732913, NCT01732926). Clinical trial information: NCT01732913, NCT01732929.

Update on a phase I study of the selective PI3Kδ inhibitor idelalisib (GS-1101) in combination with rituximab and/or bendamustine in patients with relapsed or refractory CLL

7017

Background: PI3K-delta signaling is critical for proliferation, survival, homing and tissue retention of malignant B cells. Idelalisib is a first-in-class, selective, oral inhibitor of PI3Kδ that has shown considerable monotherapy activity in pts with heavily pretreated CLL. Methods: This phase I study evaluated idelalisib continuously given at 150 mg BID in combination with rituximab (R, 375 mg/m2 every wk x 8), bendamustine (B, 70 or 90 mg/m2 x 2, every 4 wks x 6) or BR (every 4 wks x 6) for relapsed/refractory CLL. Pts still on treatment after 48 weeks were eligible to continue idelalisib on an extension study. Clinical response was evaluated according to published criteria (Hallek 2008; Cheson 2012). Results: 52 pts (23F/29M) with a median (range) age of 64 (41-87) years were enrolled. Adverse disease characteristics included bulky lymphadenopathy (62%), refractory disease (50%), multiple prior therapies (median 3, range: 1-14) with 96% receiving prior R and 44% receiving prior B. As of 14 Jan 2013, the median (range) treatment duration was 18 (1-33) months. 31/52 (60%) pts enrolled into the extension study; of those, 24/52 (46%) pts are continuing idelalisib treatment on the extension study. The ORR was 81%, with 1 CR, and a median (range) time to response of 1.9 (1.5-8.3) months. The 2-year PFS and OS were 62% and 85%, respectively. At 2 years follow up, 71% of responses were still enduring. There was no difference in outcomes for pts with <3 prior treatments (n=21) vs ≥3 prior treatments (n=31). The most common TEAEs (any Grade/≥Gr 3, independent of causality) included pyrexia (44%/6%), diarrhea (40%/14%), cough (31%/2%), fatigue (29%/2%), nausea (29%/0%). Pneumonia (any Gr/≥Gr 3) occurred in 15%/12% and rash was seen in 15%/0%. 10% of patients experienced ≥Gr 3 ALT/AST elevation based on laboratory values. Conclusions: A lack of overlapping toxicities allowed idelalisib to be co-administered with R, B, or BR, and all 3 combination regimens were highly active, resulting in durable tumor control in pts with heavily pretreated relapsed/refractory CLL. Phase III trials evaluating the efficacy of idelalisib in combination with R or BR are ongoing. Clinical trial information: NCT01088048.

Preliminary results of PI3Kδ inhibitor idelalisib (GS-1101) treatment in combination with everolimus, bortezomib, or bendamustine/rituximab in patients with previously treated mantle cell lymphoma (MCL)

8501

Background: PI3K-delta is critical for activation, proliferation and survival of B cells and plays a role in homing and retention in lymphoid tissues. PI3Kδ signaling is hyperactive in many B-cell malignancies. Idelalisib is a first-in-class, selective, oral inhibitor of PI3Kδ that has shown monotherapy activity in recurrent MCL (Kahl, ICML 2011). Methods: This phase 1 study is evaluating the activity of continuous idelalisib (Id), 150 mg BID, in combination with everolimus (E) (10 mg PO qD) (Id+E regimen), with bortezomib (V) (1.3 mg/m2 SC day 1, 8, 15 per 28 day cycle) (Id+V regimen), or with rituximab (R) (375 mg/m2, on Day 1) and bendamustine (B) (90 mg/m2x 2), for 6 cycles (Id+BR regimen). Investigators assessed response according to standard criteria (Cheson 2007). Results: Study enrolled 22 patients with relapsed/refractory MCL. Results are from 14 Jan 2013 data cutoff. The 3 cohorts included Id+E (N=12), Id+V (N=6), and Id+BR (N=4). Patients were 73% male, median age [range] of 68 [47E79] years, 32% with refractory disease and 73% stage III/IV. The median [range] number of prior therapies was 3 [1E7]. The median [range] duration of treatment was 2.5 [0.5-8.3+] months. Overall response rate (ORR) was 10/22 (46%), with 2 CR (9%). The ORR/CR for Id+E, was 25%/0%, Id+V was 50%/0%, and Id+BR was 100%/50%. The median duration of response (mDOR) and median PFS (mPFS) were not reached. Most common adverse events included (total%/≥G3%) diarrhea (41/9), fatigue (41/0), rash (27/14), cough (27/0), decreased appetite (23/0), and epistaxis (23/0). Lab abnormalities included (total%/≥G3%) thrombocytopenia (82/27), neutropenia (32/14), and ALT/AST elevations (50/5). Conclusions: Preliminary data indicates idelalisib-based combination therapy is active in patients with relapsed/refractory MCL. All combinations were tolerable. These data support further clinical development in larger trials to further characterize safety and response duration. Clinical trial information: NCT01088048.

A phase I study of pulse high-dose vorinostat (V) plus rituximab (R), ifosphamide, carboplatin, and etoposide (ICE) in patients with relapsed lymphoma

Given the poor outcomes of relapsed aggressive lymphomas and preclinical data suggesting that ≥2·5 μmol/l concentrations of vorinostat synergize with both etoposide and platinums, we hypothesized that pulse high-dose vorinostat could safely augment the anti-tumour activity of (R)ICE [(rituximab), ifosphamide, carboplatin, etoposide] chemotherapy. We conducted a phase I dose escalation study using a schedule with oral vorinostat ranging from 400 mg/d to 700 mg bid for 5 d in combination with the standard (R)ICE regimen (days 3, 4 and 5). Twenty-nine patients [median age 56 years, median 2 prior therapies, 14 chemoresistant (of 27 evaluable), 2 prior transplants] were enrolled and treated. The maximally tolerated vorinostat dose was defined as 500 mg twice daily × 5 d. Common dose limiting toxicities included infection (n = 2), hypokalaemia (n = 2), and transaminitis (n = 2). Grade 3 related gastrointestinal toxicity was seen in 9 patients. The median vorinostat concentration on day 3 was 4·5 μmol/l (range 4·2-6·0 μmol/l) and in vitro data confirmed the augmented antitumour and histone acetylation activity at these levels. Responses were observed in 19 of 27 evaluable patients (70%) including 8 complete response/unconfirmed complete response. High-dose vorinostat can be delivered safely with (R)ICE, achieves potentially synergistic drug levels, and warrants further study, although adequate gastrointestinal prophylaxis is warranted.

Bruton tyrosine kinase inhibitor ibrutinib (PCI-32765) has significant activity in patients with relapsed/refractory B-cell malignancies

PURPOSE

Survival and progression of mature B-cell malignancies depend on signals from the B-cell antigen receptor, and Bruton tyrosine kinase (BTK) is a critical signaling kinase in this pathway. We evaluated ibrutinib (PCI-32765), a small-molecule irreversible inhibitor of BTK, in patients with B-cell malignancies.

PATIENTS AND METHODS

Patients with relapsed or refractory B-cell lymphoma and chronic lymphocytic leukemia received escalating oral doses of ibrutinib. Two schedules were evaluated: one, 28 days on, 7 days off; and two, once-daily continuous dosing. Occupancy of BTK by ibrutinib in peripheral blood was monitored using a fluorescent affinity probe. Dose escalation proceeded until either the maximum-tolerated dose (MTD) was achieved or, in the absence of MTD, until three dose levels above full BTK occupancy by ibrutinib. Response was evaluated every two cycles.

RESULTS

Fifty-six patients with a variety of B-cell malignancies were treated over seven cohorts. Most adverse events were grade 1 and 2 in severity and self-limited. Dose-limiting events were not observed, even with prolonged dosing. Full occupancy of the BTK active site occurred at 2.5 mg/kg per day, and dose escalation continued to 12.5 mg/kg per day without reaching MTD. Pharmacokinetic data indicated rapid absorption and elimination, yet BTK occupancy was maintained for at least 24 hours, consistent with the irreversible mechanism. Objective response rate in 50 evaluable patients was 60%, including complete response of 16%. Median progression-free survival in all patients was 13.6 months.

CONCLUSION

Ibrutinib, a novel BTK-targeting inhibitor, is well tolerated, with substantial activity across B-cell histologies.

A phase I/II study of the selective phosphatidylinositol 3-kinase-delta (PI3Kδ) inhibitor, GS-1101 (CAL-101), with ofatumumab in patients with previously treated chronic lymphocytic leukemia (CLL)

6518^

Background: PI3Kδ is expressed in cells of hematopoietic origin where it regulates the survival and proliferation of malignant B-cells. GS-1101 is an orally bioavailable, small-molecule inhibitor that selectively targets PI3Kδ and is highly active in patients with hematologic malignancies. Methods: This Phase 1/2 study evaluated repeated 28-day cycles of GS‑1101 in combination with ofatumumab. GS-1101 (150mg BID) was co-administered with a total of 12 infusions of ofatumumab over 24 weeks (300mg initial dose either on Day 1 or Day 2 (relative to the first dose of GS-1101), followed 1 week later by 1,000mg weekly for 7 doses, followed 4 weeks later by 1,000mg every 4 weeks for 4 doses). Thereafter, each subjects received single-agent GS‑1101 as long as the subject was benefitting. Results: Accrual is complete with 21 subjects enrolled and 11 evaluable. Six subjects started ofatumumab treatment on Day 1 and 5 on Day 2. Median [range] age was 63 [54‑76] years. The majority (9/11; 82%) of patients had bulky adenopathy. The median [range] number of prior therapies was 3 [1‑6], including prior exposure to alkylating agents (10/11; 90%), rituximab (9/11; 82%), purine analogs (8/11; 72%), alemtuzumab (3/11; 28%) and/or ofatumumab (2/11;18%). At the data cutoff, the median [range] treatment duration was 5 [0‑7] cycles. Almost all subjects (9/11;82%) experienced marked and rapid reductions in lymphadenopathy within the first 2 cycles. The lymphocyte mobilization that is expected with PI3Kδ inhibition was significantly reduced in magnitude and duration and persisted past Cycle 1 in only 1 patient. Early follow up data support a favorable safety profile and confirm a lack of clinically significant myelosuppression. Elevated baseline levels of CCL3, CCL4, CXCL13, and TNFa were significantly reduced after 28 days of treatment. Conclusions: GS-1101/ofatumumab offers a well-tolerated noncytotoxic combination regimen with substantial activity in previously treated patient with bulky adenopathy. Data on the complete cohort of 21 subjects will be presented.

Efficacy and safety of IMO-2055, a novel TLR9 agonist, in combination with erlotinib (E) and bevacizumab (bev) in patients (pts) with advanced or metastatic non-small cell lung cancer (NSCLC) who have progressed following prior chemotherapy

e18047

Background: IMO-2055 is a novel TLR-9 agonist with potential to enhance the efficacy of biologics and small molecules through immune stimulation. Xenograft data show anti-tumor synergy between IMO-2055, E and bev; E-bev has been evaluated in 2nd line NSCLC. Methods: Primary objective was to determine the recommended dose (RD) of IMO-2055 (dose range 0.08-0.48 mg/kg/w s.c.) with E 150mg/day p.o. and bev 15mg/kg q3w i.v. in a standard 3+3 design. An expansion cohort at the RD further determined safety and efficacy. Pts had AJCC stage 3/4 inoperable, histologically proven NSCLC where standard chemotherapy was not an option. Treatment was until progression (PD) or toxicity. Results: 36 pts were enrolled at 10 US sites from Nov ‘07 to Mar '11. 35 were treated/evaluable for safety; 33 for efficacy. Median age was 64, 58% were men, 81% white, 81% PS 1 with 69% adenocarcinomas and median 17 months since diagnosis. 44% pts were >2nd line. Pts received a median of 4.3 3-week cycles. 19 pts entered dose-escalation: 4 at 0.08 mg/kg, 6 at 0.16 mg/kg, 6 at 0.32 mg/kg, and 3 at 0.48 mg/kg IMO-2055. Two pts had DLTs: 1 grade 3 dehydration at 0.16 mg/kg, and 1 grade 3 fatigue at 0.48 mg/kg. RD was 0.32 mg/kg based on pharmacodynamic and clinical data: 17 more pts were treated at this dose. The most common AEs were diarrhea, nausea, fatigue and rash; most frequent grade 3-4 AEs were fatigue (9%), diarrhea (9%), anemia and dyspnea (both 6%), with no clear dose-relationship to IMO-2055. G3-4 hypertension was 0%, ATE 6% and hemorrhage 3%. Five pts died of PD on or within 30 days of study drug administration. Response rate was 12% with 79% disease control (SD+PR). Median PFS was 5.6 months (95% CI 3.9-7.2) and OS 16 months (95% CI 7.5-17.8) with 55% pts alive at 1 year. Conclusions: Addition of IMO-2055 to E-bev was well tolerated with no unexpected toxicity. The RD of IMO-2055 with E-bev is 0.32 mg/kg/w s.c.  Median PFS and OS in this heavily pretreated population compare favorably with published E-bev data.  IMO-2055 should be further explored in NSCLC.

CD30 expression in nonlymphomatous malignancies

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Background: CD30 is commonly expressed in Hodgkin lymphoma (HL), anaplastic large cell lymphoma (ALCL), and testicular embryonal carcinoma. Expression of CD30 in other solid tumors and non-lymphomatous malignancies has been reported but not investigated systematically. CD30 is the target of brentuximab vedotin (Adcetris), an antibody drug conjugate (ADC) that is approved for the treatment of patients with relapsed HL and systemic ALCL after failure of other therapies. A study was initiated to determine the incidence of CD30 expression in non-lymphomatous malignancies and to identify patients who may be candidates for treatment with brentuximab vedotin. Methods: Patients with non-lymphomatous malignancies were eligible for screening if they were relapsed or refractory to previous therapy or had no effective treatment options available. Archived tissue from solid tumors was tested for CD30 expression by immunohistochemistry (IHC); fresh bone marrow or blood samples from multiple myeloma or leukemia patients were tested by flow cytometry. Patients were considered CD30 positive and eligible for a companion treatment protocol with brentuximab vedotin if ≥10% of malignant cells stained positive by IHC or ≥20% by flow cytometry. Results: At this interim analysis, a total of 875 patients have been tested for CD30 expression: 95% had solid tumors, 3% had leukemia, and 2% had multiple myeloma. Twenty-two patients (2.5%) were CD30 positive, including 7 of 94 patients with ovarian cancer (7%), 5 of 20 with melanoma (25%), 2 of 5 with mesothelioma (40%), 1 of 4 with skin squamous cell carcinoma (25%), 2 of 41 with triple negative breast cancer (5%), 1 of 37 with pancreatic cancer (3%), 1 of 26 with small cell lung cancer (4%), and 1 of 3 with anal cancer (33%), and thyroid carcinoma (33%). One patient was identified with CD30-positive mast cell leukemia. In positive patients, the percent of CD30-positive malignant cells varied between 10 and 80%. Conclusions: CD30 expression was observed in multiple types of non-lymphomatous malignancies, thereby identifying additional populations who may be candidates for treatment with a CD30-targeted ADC, such as brentuximab vedotin. A companion clinical trial with brentuximab vedotin is currently ongoing.

5-year survival in patients with relapsed or refractory chronic lymphocytic leukemia in a randomized, phase III trial of fludarabine plus cyclophosphamide with or without oblimersen

PURPOSE

A randomized trial of oblimersen plus fludarabine/cyclophosphamide (OBL-FC; n = 120) versus FC (n = 121) was conducted in patients with relapsed/refractory chronic lymphocytic leukemia (CLL). The primary end point was met: the complete response (CR) rate, defined as complete or nodular partial response, was significantly greater with OBL-FC than with FC (17% v 7%; P = .025). Among patients with CR, response duration was significantly longer with OBL-FC than with FC (median not reached; > 36 months v 22 months; P = .03). Maximum benefit with OBL-FC, including a four-fold increase in CR rate and a survival benefit with 3 years of follow-up (hazard ratio, 0.53; P = .05), was observed in patients with fludarabine-sensitive disease. We evaluated long-term survival and poststudy CLL therapy among all randomly assigned patients.

METHODS

Poststudy CLL treatment information was collected. Patients were observed for survival for up to 5 years from the date of random assignment.

RESULTS

Poststudy CLL treatment was balanced between arms. Intent-to-treat analysis of 5-year survival showed no significant between-treatment difference (hazard ratio, 0.87; P = .34). Among the greater than 40% of patients with complete or partial remission, a significant 5-year survival benefit was observed with OBL-FC (hazard ratio, 0.60; P = .038). Among patients with fludarabine-sensitive disease who had previously demonstrated maximum benefit with OBL-FC, the previously observed survival benefit improved: a 50% reduction in the risk of death was observed (P = .004).

CONCLUSION

In relapsed/refractory CLL, OBL combined with FC offers patients who achieve complete or partial remission, as well as those who have fludarabine-sensitive disease, a significant survival benefit.

Randomized phase III trial of fludarabine plus cyclophosphamide with or without oblimersen sodium (Bcl-2 antisense) in patients with relapsed or refractory chronic lymphocytic leukemia

PURPOSE

Expression of Bcl-2 protein is associated with chemotherapy resistance and decreased survival in chronic lymphocytic leukemia (CLL). We evaluated whether oblimersen would improve response to chemotherapy in patients with relapsed or refractory CLL.

PATIENTS AND METHODS

Patients had received at least one prior fludarabine-containing regimen and were stratified on the basis of prior fludarabine response, number of prior regimens, and duration of response to last prior therapy. Patients were randomly assigned to 28-day cycles of fludarabine 25 mg/m2/d plus cyclophosphamide 250 mg/m2/d administered intravenously for 3 days with or without oblimersen 3 mg/kg/d as a 7-day continuous intravenous infusion (beginning 4 days before chemotherapy) for up to six cycles. The primary end point was the proportion of patients who achieved complete response (CR) or nodular partial response (nPR).

RESULTS

Of 241 patients randomly assigned, CR/nPR was achieved in 20 (17%) of 120 patients in the oblimersen group and eight (7%) of 121 patients in the chemotherapy-only group (P = .025). Achievement of CR/nPR was correlated with both an extended time to progression and survival (P < .0001). In patients who remained sensitive to fludarabine, oblimersen was associated with a four-fold increase in the CR/nPR rate and a significant survival benefit (P = .05). Oblimersen was frequently associated with thrombocytopenia and, rarely, tumor lysis syndrome and cytokine release reactions; the incidence of opportunistic infections and second malignancies was similar in both groups.

CONCLUSION

The addition of oblimersen to fludarabine plus cyclophosphamide significantly increases the CR/nPR rate in patients with relapsed or refractory CLL (particularly fludarabine-sensitive patients), as well as response duration among patients who achieve CR/nPR.

Cholinergic modulation of neocortical long-term potentiation in the awake, freely moving rat

The neocortex has proven resistant to LTP induction using standard in vitro and acute, in vivo preparations. Because the neocortex is widely thought to be involved in long-term information storage, this resistance raises questions about the validity of LTP as a memory model. Recently, we have shown that the neocortex of freely moving rats reliably supports LTP, provided that the stimulation is spaced and repeated over days. The following experiments were designed to evaluate the neuromodulatory role played by cholinergic systems in the induction of LTP in this preparation. Chronically implanted rats received either low- or high-intensity LTP-inducing tetani in combination with the administration of either a cholinergic agonist or antagonist injected systemically. Potentiation was evidenced as amplitude changes in both early and late components of the evoked field potential, the former including population spikes. The cholinergic agonist facilitated LTP induction in the late component of both high- and low-intensity groups. The cholinergic antagonist blocked LTP induction in the early component of the high-intensity group. The possibility that there are component-specific modulatory effects of cholinergic agents on the induction of neocortical LTP is discussed.