Thomas A. Puchalski

Siltuximab for multicentric Castleman's disease: a randomised, double-blind, placebo-controlled trial

BACKGROUNDnMulticentric Castlemans disease is a rare lymphoproliferative disorder driven by dysregulated production of interleukin 6. No randomised trials have been done to establish the best treatment for the disease. We assessed the safety and efficacy of siltuximab-a chimeric monoclonal antibody against interleukin 6-in HIV-negative patients with multicentric Castlemans disease.nnnMETHODSnWe did this randomised, double-blind, placebo-controlled study at 38 hospitals in 19 countries worldwide. We enrolled HIV-negative and human herpesvirus-8-seronegative patients with symptomatic multicentric Castlemans disease. Treatment allocation was randomised with a computer-generated list, with block size six, and stratification by baseline corticosteroid use. Patients and investigators were masked to treatment allocation. Patients were randomly assigned (2:1) to siltuximab (11 mg/kg intravenous infusion every 3 weeks) or placebo; all patients also received best supportive care. Patients continued treatment until treatment failure. The primary endpoint was durable tumour and symptomatic response for at least 18 weeks for the intention-to-treat population. Enrolment has been completed. The study is registered with ClinicalTrials.gov, number NCT01024036.nnnFINDINGSnWe screened 140 patients, 79 of whom were randomly assigned to siltuximab (n=53) or placebo (n=26). Durable tumour and symptomatic responses occurred in 18 (34%) of 53 patients in the siltuximab group and none of 26 in the placebo group (difference 34·0%, 95% CI 11·1-54·8, p=0·0012). The incidence of grade 3 or more adverse events (25 [47%] vs 14 [54%]) and serious adverse events (12 [23%] vs five [19%]) was similar in each group despite longer median treatment duration with siltuximab than with placebo (375 days [range 1-1031] vs 152 days [23-666]). The most common grade 3 or higher were fatigue (five vs one), night sweats (four vs one), and anaemia (one vs three). Three (6%) of 53 patients had serious adverse events judged reasonably related to siltuximab (lower respiratory tract infection, anaphylactic reaction, sepsis).nnnINTERPRETATIONnSiltuximab plus best supportive care was superior to best supportive care alone for patients with symptomatic multicentric Castlemans disease and well tolerated with prolonged exposure. Siltuximab is an important new treatment option for this disease.nnnFUNDINGnJanssen Research & Development.

A Phase I, Open-Label Study of Siltuximab, an Anti–IL-6 Monoclonal Antibody, in Patients with B-cell Non-Hodgkin Lymphoma, Multiple Myeloma, or Castleman Disease

Purpose: To evaluate the safety and pharmacokinetics of siltuximab, an anti–interleukin-6 chimeric monoclonal antibody (mAb) in patients with B-cell non-Hodgkin lymphoma (NHL), multiple myeloma, or Castleman disease. Experimental Design: In an open-label, dose-finding, 7 cohort, phase I study, patients with NHL, multiple myeloma, or symptomatic Castleman disease received siltuximab 3, 6, 9, or 12 mg/kg weekly, every 2 weeks, or every 3 weeks. Response was assessed in all disease types. Clinical benefit response (CBR; composite of hemoglobin, fatigue, anorexia, fever/night sweats, weight, largest lymph node size) was also evaluated in Castleman disease. Results: Sixty-seven patients received a median of 16 siltuximab doses for a median of 8.5 (maximum 60.5) months; 29 were treated 1 year or longer. There was no dose-limiting toxicity, antibodies to siltuximab, or apparent dose–toxicity relationship. The most frequently reported possible drug-related adverse events were thrombocytopenia (25%), hypertriglyceridemia (19%), neutropenia (19%), leukopenia (18%), hypercholesterolemia (15%), and anemia (10%). None of these events led to dose delay/discontinuation except for neutropenia and thrombocytopenia (n = 1 each). No treatment-related deaths occurred. C-reactive protein (CRP) suppression was most pronounced at 12 mg/kg every 3 weeks. Mean terminal-phase half-life of siltuximab ranged 17.73 to 20.64 days. Thirty-two of 37 (86%) patients with Castleman disease improved in 1 or more CBR component; 12 of 36 evaluable Castleman disease patients had radiologic response [complete response (CR), n = 1; partial response (PR), n = 11], including 8 of 19 treated with 12 mg/kg; 2 of 14 (14%) evaluable NHL patients had PR; 2 of 13 (15%) patients with multiple myeloma had CR. Conclusion: No dose-related or cumulative toxicity was apparent across all disease indications. A dose of 12 mg/kg every 3 weeks was recommended on the basis of the high response rates in Castleman disease and the sustained CRP suppression. Randomized studies are ongoing in Castleman disease and multiple myeloma. Clin Cancer Res; 19(13); 3659–70. ©2013 AACR.

Phase 2 study of carlumab (CNTO 888), a human monoclonal antibody against CC-chemokine ligand 2 (CCL2), in metastatic castration-resistant prostate cancer

SummaryBackground CC-chemokine ligand 2 (CCL2) promotes tumor growth by angiogenesis, macrophage infiltration and tumor invasion, and distant metastasis. Carlumab (CNTO 888) is a human IgG1κ mAb with high affinity and specificity for human CCL2. Preclinical data suggest carlumab may offer clinical benefit to cancer patients. Methods In a phase 2, open-label study, patients with metastatic castration-resistant prostate cancer (CRPC) previously treated with docetaxel received a 90-min infusion of 15xa0mg/kg carlumab q2w. The primary endpoint was response rate: change from baseline in skeletal lesions, extraskeletal lesions, and PSA values. Secondary endpoints included overall response rate (CR + PR) by RECIST, OS, PSA response, safety, pharmacodynamics, pharmacokinetics, immunogenicity. Results Forty-six patients were treated with 6 median (range 1, 26) doses. One patient had SD >6xa0months. There were no PSA or RECIST responses. Fourteen (34xa0%) patients had SD ≥3xa0months. Median OS was 10.2 (95xa0% CI: 5.2, not estimable) months. Twelve (39xa0%) patients reported improved pain scores. AEs occurred in 43 (93xa0%) patients, including 27 (59xa0%) with grade ≥3xa0AEs. Common grade ≥3xa0AEs were back (11xa0%) and bone (9xa0%) pain. Twenty (43xa0%) patients experienced SAEs, including pneumonia, spinal cord compression, back pain. No patient developed antibodies to carlumab. Steady-state serum concentrations were achieved after 3 repeated doses and were above the 10-μg/mL target concentration. Suppression of free CCL2 serum concentrations was briefly observed following each dose but was not sustained. Conclusion Carlumab was well-tolerated but did not block the CCL2/CCR2 axis or show antitumor activity as a single agent in metastatic CRPC.

A first-in-human, first-in-class, phase I study of carlumab (CNTO 888), a human monoclonal antibody against CC-chemokine ligand 2 in patients with solid tumors

PurposeThe CC-chemokine ligand 2 (CCL2) is highly expressed in various malignancies and promotes carcinogenesis. Blocking CCL2 has preclinical antitumor activity. A phase 1 trial of carlumab (CNTO 888), a human anti-CCL2 IgG1κ mAb, was conducted to evaluate the safety, tolerability, pharmacokinetic–pharmacodynamic profile, and antitumor activity.MethodsPatients with advanced solid malignancy received escalating doses of carlumab 0.3, 1, 3, 10, or 15xa0mg/kg by 90-min intravenous infusion on days 1, 28, and every 2xa0weeks thereafter (dose escalation) or 10 or 15xa0mg/kg every 2xa0weeks (dose-expansion). Pharmacodynamic assessments were also performed.ResultsForty-four patients received 206 doses of carlumab. MTD was not established. Carlumab-related adverse events included grade 1–2 fatigue (9xa0%), nausea (7xa0%), headache (7xa0%), vomiting (5xa0%), and pruritus (5xa0%). The recommended phase II dose was 15xa0mg/kg every 2xa0weeks. Carlumab concentrations declined bi-exponentially with a terminal half-life of 6.6–9.6xa0days. Free CCL2 was transiently suppressed, while total CCL2 increased dose-dependently >1,000-fold post-treatment. A patient with ovarian cancer and a patient with prostate cancer achieved CA125 and PSA reductions of >50xa0% and RECIST SD for 10.5 and 5xa0months, respectively. Two other patients had RECIST SD for 7.2 and 15.7xa0months.ConclusionsCarlumab was well tolerated with evidence of transient free CCL2 suppression and preliminary antitumor activity.

The anti-interleukin-6 antibody siltuximab down-regulates genes implicated in tumorigenesis in prostate cancer patients from a phase I study†‡§

Interleukin‐6 (IL‐6) is associated with prostate cancer morbidity. In several experimental models, IL‐6 has been reported to have anti‐apoptotic and pro‐angiogenic effects. Siltuximab (CNTO 328) is a monoclonal anti‐IL‐6 antibody which has been successfully applied in several models representing prostate cancer. This study was designed to assess preliminary safety of siltuximab in patients with early prostate cancer.

Pharmacokinetic and Pharmacodynamic Modeling of an Anti–Interleukin-6 Chimeric Monoclonal Antibody (Siltuximab) in Patients with Metastatic Renal Cell Carcinoma

Purpose: Interleukin-6 (IL-6) induces tumor growth, invasion, metastasis, and angiogenesis. Siltuximab (CNTO 328) is a chimeric, murine-human monoclonal antibody that specifically binds human IL-6 with high affinity. C-reactive protein (CRP) can be a pharmacodynamic (PD) marker of IL-6 bioactivity. Reductions in CRP may correlate with clinical activity and IL-6 bioactivity. Experimental Design: Starting-dose selection for this study was based on a previous siltuximab study in multiple myeloma patients. Pharmacokinetic (PK)/PD modeling explored the relationship between siltuximab PK and CRP suppression following i.v. siltuximab infusion in a three-part phase I/II study in 68 metastatic renal cell carcinoma patients. Modeling results were then used to simulate and determine which siltuximab dosage regimens would maintain CRP suppression below the lower limit of quantification (4 mg/L). Siltuximab was given at 1, 3, 6, or 12 mg/kg at weeks 1 and 4 and then every 2 weeks for 2 cycles in part 1; at 3 or 6 mg/kg every 3 weeks for 4 cycles in part 2; and at 6 mg/kg every 2 weeks for 6 cycles in part 3. Results: A two-compartment PK model adequately described the serum siltuximab concentration-time data. An inhibitory indirect response PD model examined the relationship between siltuximab concentrations and CRP suppression. PD parameter estimates seemed reliable and physiologically relevant. Simulations showed that 6 mg/kg siltuximab every 2 weeks or 9 mg/kg every 3 weeks would reduce serum CRP to below 4 mg/L. Conclusions: Using a stepwise design, PK/PD modeling was used to select the dose levels in this study. Furthermore, PK/PD modeling results were used to help select doses to be used in future siltuximab clinical development. Clin Cancer Res; 16(5); 1652–61

A Phase I/II, Multiple-Dose, Dose-Escalation Study of Siltuximab, an Anti-Interleukin-6 Monoclonal Antibody, in Patients with Advanced Solid Tumors

Purpose: This phase I/II study evaluated safety, efficacy, and pharmacokinetics of escalating, multiple doses of siltuximab, a chimeric anti-interleukin (IL)-6 monoclonal antibody derived from a new Chinese hamster ovary (CHO) cell line in patients with advanced/refractory solid tumors. Experimental Design: In the phase I dose-escalation cohorts, 20 patients with advanced/refractory solid tumors received siltuximab 2.8 or 5.5 mg/kg every 2 weeks or 11 or 15 mg/kg every 3 weeks intravenously (i.v.). In the phase I expansion (n = 24) and phase II cohorts (n = 40), patients with Kirsten rat sarcoma-2 (KRAS)-mutant tumors, ovarian, pancreatic, or anti-EGF receptor (EGFR) refractory/resistant non–small cell lung cancer (NSCLC), colorectal, or H&N cancer received 15 mg/kg every 3 weeks. The phase II primary efficacy endpoint was complete response, partial response, or stable disease >6 weeks. Results: Eighty-four patients (35 colorectal, 29 ovarian, 9 pancreatic, and 11 other) received a median of three (range, 1–45) cycles. One dose-limiting toxicity occurred at 5.5 mg/kg. Common grade ≥3 adverse events were hepatic function abnormalities (15%), physical health deterioration (12%), and fatigue (11%). Ten percent of patients had siltuximab-related grade ≥3 adverse events. Neutropenia (4%) was the only possibly related adverse event grade ≥3 reported in >1 patient. Serious adverse events were reported in 42%; most were related to underlying disease. The pharmacokinetic profile of CHO-derived siltuximab appears similar to the previous cell line. No objective responses occurred; 5 of 84 patients had stable disease >6 weeks. Hemoglobin increased ≥1.5 g/dL in 33 of 47 patients. At 11 and 15 mg/kg, completely sustained C-reactive protein suppression was observed. Conclusions: Siltuximab monotherapy appears to be well tolerated but without clinical activity in solid tumors, including ovarian and KRAS-mutant cancers. The recommended phase II doses were 11 and 15 mg/kg every 3 weeks. Clin Cancer Res; 20(8); 2192–204. ©2014 AACR.

A phase 2, randomized, double-blind, placebo-controlled study of siltuximab (anti-IL-6 mAb) and bortezomib versus bortezomib alone in patients with relapsed or refractory multiple myeloma.

We compared the safety and efficacy of siltuximab (S), an anti‐interleukin‐6 chimeric monoclonal antibody, plus bortezomib (B) with placebo (plc) + B in patients with relapsed/refractory multiple myeloma in a randomized phase 2 study. Siltuximab was given by 6 mg/kg IV every 2 weeks. On progression, B was discontinued and high‐dose dexamethasone could be added to S/plc. Response and progression‐free survival (PFS) were analyzed pre‐dexamethasone by European Group for Blood and Marrow Transplantation (EBMT) criteria. For the 281 randomized patients, median PFS for S + B and plc + B was 8.0 and 7.6 months (HR 0.869, P = 0.345), overall response rate was 55 versus 47% (P = 0.213), complete response rate was 11 versus 7%, and median overall survival (OS) was 30.8 versus 36.8 months (HR 1.353, P = 0.103). Sustained suppression of C‐reactive protein, a marker reflective of inhibition of interleukin‐6 activity, was seen with S + B. Siltuximab did not affect B pharmacokinetics. Siltuximab/placebo discontinuation (75 versus 66%), grade ≥3 neutropenia (49 versus 29%), thrombocytopenia (48 versus 34%), and all‐grade infections (62 versus 49%) occurred more frequently with S + B. The addition of siltuximab to bortezomib did not appear to improve PFS or OS despite a numerical increase in response rate in patients with relapsed or refractory multiple myeloma.

A phase 1 study of a chimeric monoclonal antibody against interleukin-6, siltuximab, combined with docetaxel in patients with metastatic castration-resistant prostate cancer

SummaryPurpose Siltuximab is a chimeric, anti-interleukin-6 monoclonal antibody with potential therapeutic benefit in castration-resistant prostate cancer (CRPC) patients. We assessed the safety and tolerability of siltuximab in combination with docetaxel, the pharmacokinetics of docetaxel alone and with siltuximab, and the efficacy and pharmacodynamics of siltuximab plus docetaxel. Patients and Methods In an open-label, dose-escalation, multicenter, phase 1 study, patients with metastatic, progressive CRPC received docetaxel 75xa0mg/m2 q3w plus siltuximab 6xa0mg/kg q2w (nu2009=u200912), 9xa0mg/kg q3w (nu2009=u200912), or 12xa0mg/kg q3w (nu2009=u200915). Dose-limiting toxicity (DLT), PSA, and radiologic response according to WHO criteria were evaluated. Results DLT was reported in 1 of 11 patients receiving 6xa0mg/kg, 1 of 12 receiving 9xa0mg/kg, and in 1 of 14 receiving 12xa0mg/kg. Common Grade ≥3 adverse events were neutropenia (73xa0%), leukopenia (60xa0%), lymphopenia (30xa0%), dyspnea (19xa0%), and fatigue (14xa0%). Toxicities were not dose dependent. Siltuximab did not affect docetaxel pharmacokinetics. The pharmacokinetic profile for siltuximab in combination was similar to single-agent siltuximab pharmacokinetics. Twenty-three (62xa0%; 95xa0% CI 45xa0%, 78xa0%) of 37 combination-treated patients achieved a confirmed u2009≥u200950xa0% PSA decline. Of 17 patients with measurable disease at baseline, 2 confirmed and 2 unconfirmed radiologic partial responses ranging 190 to 193xa0days were achieved with 9- and 12-mg/kg siltuximab. C-reactive protein concentrations were suppressed throughout treatment in all patients. Conclusion These results suggest that siltuximab in combination with docetaxel is safe and shows preliminary efficacy in patients with CRPC, although alternative siltuximab schedules may be better tolerated for future studies.

Carlumab, an anti-C-C chemokine ligand 2 monoclonal antibody, in combination with four chemotherapy regimens for the treatment of patients with solid tumors: an open-label, multicenter phase 1b study.

C-C chemokine ligand 2 (CCL2) stimulates tumor growth, metastasis, and angiogenesis. Carlumab, a human IgG1κ anti-CCL2 mAb, has shown antitumor activity in preclinical and clinical trials. We conducted a first-in-human phase 1b study of carlumab with one of four chemotherapy regimens (docetaxel, gemcitabine, paclitaxelu2009+u2009carboplatin, and pegylated liposomal doxorubicin HCl [PLD]). Patients had advanced solid tumors for which ≥1 of these regimens was considered standard of care or for whom no other treatment options existed. Dose-limiting toxicities included one grade 4 febrile neutropenia (docetaxel arm) and one grade 3 neutropenia (gemcitabine arm). Combination treatment with carlumab had no clinically relevant pharmacokinetic effect on docetaxel (nu2009=u200915), gemcitabine (nu2009=u200912), paclitaxel or carboplatin (nu2009=u200912), or PLD (nu2009=u200914). Total serum CCL2 concentrations increased post-treatment with carlumab alone, consistent with carlumab-CCL2 binding, and continued increase in the presence of all chemotherapy regimens. Free CCL2 declined immediately post-treatment with carlumab but increased with further chemotherapy administrations in all arms, suggesting that carlumab could sequester CCL2 for only a short time. Neither antibodies against carlumab nor consistent changes in circulating tumor cells (CTCs) or circulating endothelial cells (CECs) enumeration were observed. Three of 19 evaluable patients showed a 30xa0% decrease from baseline urinary cross-linked N-telopeptide of type I collagen (uNTx). One partial response and 18 (38xa0%) stable disease responses were observed. The most common drug-related grade ≥3 adverse events were docetaxel arm—neutropenia (6/15) and febrile neutropenia (4/15); gemcitabine arm—neutropenia (2/12); paclitaxelu2009+u2009carboplatin arm—neutropenia, thrombocytopenia (4/12 each), and anemia (2/12); and PLD arm—anemia (3/14) and stomatitis (2/14). Carlumab could be safely administered at 10 or 15xa0mg/kg in combination with standard-of-care chemotherapy and was well-tolerated, although no long-term suppression of serum CCL2 or significant tumor responses were observed.