BETA PRIME: Phase I study of AdAPT-001 as monotherapy and combined with a checkpoint inhibitor in superficially accessible, treatment-refractory solid tumors.

AdAPT-001 is an investigational therapy consisting of a replicative type 5 adenovirus armed with a TGF-ß receptor-immunoglobulin Fc fusion trap, designed to neutralize isoforms 1 and 3 of the profibrotic and immunosuppressive cytokine, TGF-ß. In preclinical studies with an immunocompetent mouse model, AdAPT-001 eradicated directly treated 'cold' tumors as well as distant untreated tumors, and, from its induction of systemic CD8+ T cell-mediated antitumor immunity, protected the mice from rechallenge with tumor cells. AdAPT-001 also sensitized resistant tumors to checkpoint blockade. This manuscript describes the rationale and design of the first-in-human phase I, dose-escalation and dose-expansion study of AdAPT-001 alone and in combination with a checkpoint inhibitor in adults with treatment-refractory superficially accessible solid tumors.

The purpose of this study is to find out more about the experimental oncolytic virus called AdAPT-001 that has been designed to selectively eliminate cancer cells. The virus is also designed to make a particular protein called a TGF-ß trap, which neutralizes TGF-ß, an overproduced chemical in cancer cells that puts the immune system into a comatose state. This article discusses a clinical trial called BETA PRIME for patients with no other standard treatment options. The trial will explore different doses of AdAPT-001 both alone and in combination with an approved checkpoint inhibitor or another immunotherapy, which blocks the 'off' signal on immune cells, to determine the safest and best dose. Clinical Trial Registration: NCT04673942 (ClinicalTrials.gov).

Safety, PK/PD and preliminary anti-tumor activities of pegylated recombinant human arginase 1 (BCT-100) in patients with advanced arginine auxotrophic tumors.

Background The study determined the safety, pharmacokinetics/pharmacodynamics (PK/PD), and recommended Phase II dose of BCT-100 for arginine auxotrophic tumours in a non-Chinese population. Methods This is a Phase I, 3 + 3 dose-escalation, open-label, multi-centre study in two arginine auxotrophic cancers-Malignant Melanoma (MM) and Castration Resistant Prostate Cancer (CRPC). Patients were enrolled to receive weekly intravenous BCT-100. The dose cohorts were respectively 0.5 mg/kg, 1.0 mg/kg, 1.7 mg/kg and 2.7 mg/kg. Results There were 14 MM and 9 CRPC patients, 16 males and 7 females with a median age of 71. No dose-limiting toxicities were reported. Among all the AEs, 18 were drug-related (mostly were Grade 1). Although there were individual variations in PKs amongst the patients in each cohort, the median arginine level was maintained at 2.5 µM (lower limit of quantification) in all 4 cohorts of patients after the second BCT-100 injection. Therapeutic Arginine Depletion was found in the 1.7 and 2.7 mg/kg/week cohorts when anti-tumor activities were observed. The two cohorts had a similar AUC (20,947 and 19,614 h*µg/ml respectively). Since the 2.7 mg/kg/week cohort had a more sustained arginine depletion for 2 weeks, the 2.7 mg/kg/week dose is chosen as the future phase II dose. There were two complete remissions (1 MM & 1 CRPC), 1PR (MM) and 2 stable diseases with a disease control rate (CR + PR + SD) of 5/23 (22%). Conclusions BCT-100 is safe in a non-Chinese population and has anti-tumor activities in both MM and CRPC. Weekly BCT-100 at 2.7 mg/kg is defined as the optimal biological dose for future clinical phase II studies.

The McCAVE Trial: Vanucizumab plus mFOLFOX-6 Versus Bevacizumab plus mFOLFOX-6 in Patients with Previously Untreated Metastatic Colorectal Carcinoma (mCRC).

BACKGROUND: Bevacizumab, a VEGF-A inhibitor, in combination with chemotherapy, has proven to increase progression-free survival (PFS) and overall survival in multiple lines of therapy of metastatic colorectal cancer (mCRC). The angiogenic factor angiopoetin-2 (Ang-2) is associated with poor prognosis in many cancers, including mCRC. Preclinical models demonstrate improved activity when inhibiting both VEGF-A and Ang-2, suggesting that the dual VEGF-A and Ang-2 blocker vanucizumab (RO5520985 or RG-7221) may improve clinical outcomes. This phase II trial evaluated the efficacy of vanucizumab plus modified (m)FOLFOX-6 (folinic acid (leucovorin), fluorouracil (5-FU) and oxaliplatin) versus bevacizumab/mFOLFOX-6 for first-line mCRC. PATIENTS AND METHODS: All patients received mFOLFOX-6 and were randomized 1:1 to also receive vanucizumab 2,000 mg or bevacizumab 5 mg/kg every other week. Oxaliplatin was given for eight cycles; other agents were continued until disease progression or unacceptable toxicity for a maximum of 24 months. The primary endpoint was investigator-assessed PFS. RESULTS: One hundred eighty-nine patients were randomized (vanucizumab, n = 94; bevacizumab, n = 95). The number of PFS events was comparable (vanucizumab, n = 39; bevacizumab, n = 43). The hazard ratio was 1.00 (95% confidence interval, 0.64-1.58; p = .98) in a stratified analysis based on number of metastatic sites and region. Objective response rate was 52.1% and 57.9% in the vanucizumab and bevacizumab arm, respectively. Baseline plasma Ang-2 levels were prognostic in both arms but not predictive for treatment effects on PFS of vanucizumab. The incidence of adverse events of grade ≥3 was similar between treatment arms (83.9% vs. 82.1%); gastrointestinal perforations (10.8% vs. 8.4%) exceeded previously reported rates in this setting. Hypertension and peripheral edema were more frequent in the vanucizumab arm. CONCLUSION: Vanucizumab/mFOLFOX-6 did not improve PFS and was associated with increased rates of antiangiogenic toxicity compared with bevacizumab/mFOLFOX-6. Our results suggest that Ang-2 is not a relevant therapeutic target in first-line mCRC. IMPLICATIONS FOR PRACTICE: This randomized phase II study demonstrates that additional angiopoietin-2 (Ang-2) inhibition does not result in superior benefit over anti-VEGF-A blockade alone when each added to standard chemotherapy. Moreover, the performed pharmacokinetic and pharmacodynamic analysis revealed that vanucizumab was bioavailable and affected its intended target, thereby strongly suggesting that Ang-2 is not a relevant therapeutic target in the clinical setting of treatment-naïve metastatic colorectal cancer. As a result, the further clinical development of the dual VEGF-A and Ang-2 inhibitor vanucizumab was discontinued.

Safety and efficacy of pomalidomide, dexamethasone and pegylated liposomal doxorubicin for patients with relapsed or refractory multiple myeloma.

Immunomodulatory drugs including thalidomide, lenalidomide (LEN) and pomalidomide (POM), are effective for treating multiple myeloma (MM). POM has shown enhanced efficacy with dexamethasone (DEX). Pegylated liposomal doxorubicin (PLD) with bortezomib is US Food and Drug Administration-approved for treating MM. PLD with LEN or thalidomide has shown efficacy for MM patients. LEN with DEX, PLD and bortezomib achieves high response rates. We evaluated the combination of POM with DEX 40 mg and PLD 5 mg/m2 with the latter two drugs administered on days 1, 4, 8 and 11 on a 28-day cycle for the treatment of relapsed/refractory MM patients. During Phase 1, the maximum tolerated dose of POM was 4 mg, and was used in Phase 2, which also required patients to be refractory to LEN. However, neutropenia ≥ grade 3 was observed in 10/17 (59%) patients, and the dose was lowered to 3 mg. Median PFS was 5·4 months (range, 0·3-29·0 +  months). Overall response rates for patients in Phase 2 were 39% and 31% among subjects receiving POM at 3 mg and 4 mg, respectively, and clinical benefit rates were 51% and 44%, respectively. POM, PLD and DEX is a treatment option for relapsed/refractory MM patients including those who are refractory to LEN.

CHAMPION-1: a phase 1/2 study of once-weekly carfilzomib and dexamethasone for relapsed or refractory multiple myeloma.

Carfilzomib, a proteasome inhibitor, is approved in the United States as a single agent, and in combination with dexamethasone or lenalidomide/dexamethasone (KRd) for relapsed or refractory multiple myeloma (MM). Under the single-agent and KRd approvals, carfilzomib is administered as a 10-minute IV infusion on days 1, 2, 8, 9, 15, and 16 of 28-day cycles (20 mg/m(2) [cycle 1, days 1-2]; 27 mg/m(2) thereafter). This multicenter, single-arm, phase 1/2 study, Community Harmonized Assessment of Myeloma Patients via an Integrated Oncology Network-1 (CHAMPION-1), evaluated once-weekly carfilzomib with dexamethasone in relapsed, or relapsed and refractory MM (1-3 prior therapies). Patients received carfilzomib (30-minute IV infusion) on days 1, 8, and 15 of 28-day cycles. The phase 1 portion used a 3 + 3 dose-escalation scheme to determine the maximum tolerated dose (MTD) of carfilzomib. During phase 2, patients received carfilzomib on the same schedule at the MTD. Patients received dexamethasone (40 mg) on days 1, 8, 15, and 22; dexamethasone was omitted on day 22 for cycles 9+. A total of 116 patients were enrolled. The MTD was 70 mg/m(2), and 104 patients (phase 1/2) received carfilzomib 70 mg/m(2) At 70 mg/m(2), the median number of prior regimens was 1; and 52% were bortezomib-refractory. At 70 mg/m(2), the most common grade ≥3 adverse events were fatigue (11%) and hypertension (7%). Overall response rate at 70 mg/m(2) was 77%. Median progression-free survival was 12.6 months. These findings merit additional evaluation of the once-weekly dosing regimen. This trial was registered at www.clinicaltrials.gov as #NCT01677858.

Clinical translation of ferumoxytol-based vessel size imaging (VSI): Feasibility in a phase I oncology clinical trial population.

PURPOSE: To assess the feasibility of acquiring vessel size imaging (VSI) metrics using ferumoxytol injections and stock pulse sequences in a multicenter Phase I trial of a novel therapy in patients with advanced metastatic disease. METHODS: Scans were acquired before, immediately after, and 48 h after injection, at screening and after 2 weeks of treatment. ΔR2 , ΔR2*, vessel density (Q), and relative vascular volume fractions (VVF) were estimated in both normal tissue and tumor, and compared with model-derived theoretical and experimental estimates based on preclinical murine xenograft data. RESULTS: R2 and R2* relaxation rates were still significantly elevated in tumors and liver 48 h after ferumoxytol injection; liver values returned to baseline by week 2. Q was relatively insensitive to changes in ΔR2*, indicating lack of dependence on contrast agent concentration. Variability in Q was higher among human tumors compared with xenografts and was mostly driven by ΔR2 . Relative VVFs were higher in human tumors compared with xenografts, while values in muscle were similar between species. CONCLUSION: Clinical ferumoxytol-based VSI is feasible using standard MRI techniques in a multicenter study of patients with lesions outside of the brain. Ferumoxytol accumulation in the liver does not preclude measurement of VSI parameters in liver metastases. Magn Reson Med 77:814-825, 2017. © 2016 International Society for Magnetic Resonance in Medicine.

A randomized, placebo-controlled, phase 1/2 study of tivantinib (ARQ 197) in combination with irinotecan and cetuximab in patients with metastatic colorectal cancer with wild-type KRAS who have received first-line systemic therapy.

Cetuximab in combination with an irinotecan-containing regimen is a standard treatment in patients with KRAS wild-type (KRAS WT), metastatic colorectal cancer (mCRC). We investigated the addition of the oral MET inhibitor tivantinib to cetuximab + irinotecan (CETIRI) based on preclinical evidence that activation of the MET pathway may confer resistance to anti-EGFR therapy. Previously treated patients with KRAS WT advanced or mCRC were enrolled. The phase 1, open-label 3 + 3, dose-escalation study evaluated the safety and maximally tolerated dose of tivantinib plus CETIRI. The phase 2, randomized, double-blinded, placebo-controlled study of biweekly CETIRI plus tivantinib or placebo was restricted to patients who had received only one prior line of chemotherapy. The phase 2 primary endpoint was progression-free survival (PFS). The recommended phase 2 dose was tivantinib (360 mg/m(2) twice daily) with biweekly cetuximab (500 mg/m(2)) and irinotecan (180 mg/m(2)). Among 117 patients evaluable for phase 2 analysis, no statistically significant PFS difference was observed: 8.3 months on tivantinib vs. 7.3 months on placebo (HR, 0.85; 95% confidence interval, 0.55-1.33; P = 0.38). Subgroup analyses trended in favor of tivantinib in patients with MET-High tumors by immunohistochemistry, PTEN-Low tumors, or those pretreated with oxaliplatin, but subgroups were too small to draw conclusions. Neutropenia, diarrhea, nausea and rash were the most frequent severe adverse events in tivantinib-treated patients. The combination of tivantinib and CETIRI was well tolerated but did not significantly improve PFS in previously treated KRAS WT mCRC. Tivantinib may be more active in specific subgroups.

Safety and Efficacy of Vicriviroc (MK-7690) in Combination With Pembrolizumab in Patients With Advanced or Metastatic Microsatellite Stable Colorectal Cancer.

BACKGROUND: Pembrolizumab, a monoclonal antibody against PD-1, has shown limited efficacy in patients with microsatellite stable or mismatch repair proficient (MSS/pMMR) metastatic colorectal cancer (CRC). We evaluated vicriviroc (small-molecule C-C motif chemokine ligand 5 antagonist) plus pembrolizumab in patients with advanced or metastatic MSS/pMMR CRC. PATIENTS AND METHODS: This open-label, phase 2 trial (NCT03631407) enrolled adults with histologically confirmed, locally advanced, unresectable or metastatic CRC that was MSS per local assessment. All patients had received previous treatment with standard therapies. Patients were randomized 1:1 to vicriviroc 150 mg orally once daily plus pembrolizumab 200 mg intravenously every 3 weeks or vicriviroc 250 mg orally once daily plus pembrolizumab 200 mg intravenously every 3 weeks for up to 35 cycles (2 years). Primary endpoints were the objective response rate (ORR) as assessed by the investigator per RECIST v1.1, dose-limiting toxicities (DLTs), adverse events (AEs), and discontinuations due to AEs. RESULTS: Forty patients were enrolled and treated. ORR was 5% (95% CI, 0.1%-24.9%) in both treatment groups. There were no complete responses; 1 patient in each treatment group experienced a partial response. No patient in the vicriviroc 150 mg plus pembrolizumab group experienced a DLT. Two patients in the vicriviroc 250 mg plus pembrolizumab group experienced DLTs (1 grade 4 encephalopathy and 1 grade 4 pneumonitis). CONCLUSION: The combination of vicriviroc at doses of 150 or 250 mg plus pembrolizumab 200 mg showed limited antitumor activity in patients with advanced or metastatic MSS/pMMR CRC. Toxicity with the combination was manageable.

BETA prime: a first-in-man phase 1 study of AdAPT-001, an armed oncolytic adenovirus for solid tumors.

AdAPT-001 is an oncolytic adenovirus (OAV) with a transforming growth factor beta (TGF-ß) trap, which neutralizes the immunosuppressive and profibrotic cytokine, TGF-ß. The aim or purpose of this phase 1 study was to assess the safety and tolerability and, secondarily, the efficacy of AdAPT-001 after single intratumoral injection (IT) (Part 1) and multidose IT injection (Part 2) in patients with superficially accessible, advanced refractory solid tumors. Part 1 enrolled 9 patients with a 3 + 3 single dose-escalation safety run-in involving 2.5 × 1011, 5.0 × 1011, 1.0 × 1012 viral particles (vps). No dose-limiting toxicities or treatment-related serious adverse events (SAEs) were seen. In Part 2, a dose-expansion phase, 19 patients received AdAPT-001 at 1.0 × 1012 vps until disease progression according to Response Evaluation Criteria in Solid Tumors or RECIST 1.1. The overall responses to treatment included confirmed partial responses (3), durable stable disease ≥ 6 months (5), and progressive disease (13). AdAPT-001 is well tolerated. Evidence of an anti-tumor effect was seen in both injected and uninjected lesions. The recommended Phase 2 dose was 1.0 × 1012 vp administered by intratumoral injection once every 2 weeks. Combination of AdAPT-001 with a checkpoint inhibition is enrolling.

Phase I/II trial assessing bendamustine plus bortezomib combination therapy for the treatment of patients with relapsed or refractory multiple myeloma.

Bendamustine, active in multiple myeloma (MM), is a bifunctional mechlorethamine derivative with alkylating properties. Bortezomib, approved to treat MM, is effective in combination with alkylators. The tolerability and efficacy of bendamustine plus bortezomib in relapsed/refractory MM was assessed in an open-label, dose-escalating, phase I/II study. Patients aged ≥18 years received intravenous bendamustine 50, 70, or 90 mg/m(2) (days 1 and 4) plus bortezomib 1·0 mg/m(2) (days 1, 4, 8, and 11) for up to eight 28-day cycles. No dose-limiting toxicity was observed after cycle 1; bendamustine 90 mg/m(2) plus bortezomib 1·0 mg/m(2) was designated the maximum tolerated dose (MTD). The most common grade 3/4 adverse events were leucopenia (58%), neutropenia (50%), lymphopenia (45%), and thrombocytopenia (30%). Primary efficacy measure was overall response rate (ORR), which was the combined complete response (CR), very good partial response (VGPR), partial response (PR), and minimal response (MR). ORR was 48% (one CR, two VGPR, nine PR, and seven MR) for all 40 enrolled patients, 52% (16/31) at the MTD (90 mg/m(2) ), and 42% and 46% for prior use of bortezomib (n = 31) or alkylators (n = 28) respectively. Bendamustine plus bortezomib was well tolerated with promising efficacy in this heavily pretreated population.

IOLite: phase 1b trial of doublet/triplet combinations of dostarlimab with niraparib, carboplatin-paclitaxel, with or without bevacizumab in patients with advanced cancer.

BACKGROUND: Doublet combination therapies targeting immune checkpoints have shown promising efficacy in patients with advanced solid tumors, but it is unknown if rational triplet combinations will be well tolerated and associated with improved antitumor activity. The objective of this trial was to determine the recommended phase 2 doses (RP2Ds) and to assess the safety and efficacy of the programmed cell death protein 1 (PD-1) inhibitor dostarlimab in combination with (1) the poly(ADP-ribose) polymerase inhibitor niraparib with or without vascular endothelial growth factor inhibitor bevacizumab or (2) carboplatin-paclitaxel chemotherapy with or without bevacizumab, in patients with advanced cancer. METHODS: IOLite is a multicenter, open-label, multi-arm clinical trial. Patients with advanced solid tumors were enrolled. Patients received dostarlimab in combination with niraparib with or without bevacizumab or in combination with carboplatin-paclitaxel with or without bevacizumab until disease progression, unacceptable toxicity, or withdrawal from the study. Prespecified endpoints in all parts were to evaluate the dose-limiting toxicities (DLTs), RP2Ds, pharmacokinetics (PKs), and preliminary efficacy for each combination. RESULTS: A total of 55 patients were enrolled; patients received dostarlimab and: (1) niraparib in part A (n=22); (2) carboplatin-paclitaxel in part B (n=14); (3) niraparib plus bevacizumab in part C (n=13); (4) carboplatin-paclitaxel plus bevacizumab in part D (n=6). The RP2Ds of all combinations were determined. All combinations were safe and tolerable, with no new safety signals observed. DLTs were reported in 2, 1, 2, and 0 patients, in parts A-D, respectively. Preliminary antitumor activity was observed, with confirmed Response Evaluation Criteria in Solid Tumors v1.1 complete/partial responses reported in 4 of 22 patients (18.2%), 6 of 14 patients (42.9%), 4 of 13 patients (30.8%), and 3 of 6 (50.0%) patients, in parts A-D, respectively. Disease control rates were 40.9%, 57.1%, 84.6%, and 83.3%, in parts A-D, respectively. Dostarlimab PK was unaffected by any combinations tested. Coadministration of bevacizumab showed no impact on niraparib PKs. The overall mean PD-1 receptor occupancy was 99.0%. CONCLUSIONS: Dostarlimab was well tolerated in both doublet and triplet regimens tested, with promising antitumor activity observed with all combinations. We observed higher disease control rates in the triplet regimens than in doublet regimens. TRIAL REGISTRATION NUMBER: NCT03307785.

A phase 1/2 study of ixazomib in place of bortezomib or carfilzomib in a subsequent line of therapy for patients with multiple myeloma refractory to their last bortezomib or carfilzomib combination regimen.

Identifying effective combination regimens is a high priority in multiple myeloma (MM), as most patients eventually become refractory to their current treatments. In this study, we investigated whether the proteasome inhibitor (PI) ixazomib could delay disease progression among patients who failed regimens containing another PI, bortezomib or carfilzomib. This phase 1/2, multicenter, open-label, nonrandomized study enrolled patients who were refractory to a previous regimen containing bortezomib or carfilzomib. Patients continued the other anti-MM drugs in the regimen at the same doses and frequencies. Patients with combination regimens with unknown maximum tolerated dose (MTD) of ixazomib were enrolled in phase 1, with ixazomib starting at 3 mg and then dose escalated to 4 mg. Patients on regimens with a known ixazomib MTD were enrolled in phase 2. Primary endpoints were overall response rate (ORR), clinical benefit rate (CBR), adverse events (AEs), and determination of maximum tolerated dose (MTD). Of the 46 patients enrolled, 39 were evaluable for efficacy. ORR and CBR were 12.8% and 17.9%, respectively. Ixazomib appeared to be well tolerated as a replacement for carfilzomib and bortezomib, with 23.9% of patients experiencing at least one grade ≥3 serious adverse event (SAE) and 37.0% experiencing at least one grade ≥3 AE. The most common grade ≥3 AEs were hyponatremia (8.7%), anemia (8.7%), dyspnea (8.7%), thrombocytopenia (6.5%), dehydration (4.3%), and pneumonia (4.3%). The results indicate that ixazomib is not an effective replacement for bortezomib or carfilzomib for patients with MM who have previously relapsed on other bortezomib/carfilzomib-containing regimens.

A modified regimen of pegylated liposomal doxorubicin, bortezomib and dexamethasone (DVD) is effective and well tolerated for previously untreated multiple myeloma patients.

The combination of pegylated liposomal doxorubicin (PLD), bortezomib and dexamethasone has shown efficacy in the treatment of multiple myeloma (MM) patients. Our earlier retrospective study suggested that modification of the doses, schedules and route of administration of these drugs appears to reduce toxicity without compromising anti-MM activity. As a result, we evaluated this modified drug combination in the frontline setting in a prospective multicentre phase II trial. Thirty-five previously untreated MM patients were enrolled. Dexamethasone IV 40 mg, bortezomib 1 mg/m(2) and PLD 5 mg/m(2) were administered on days 1, 4, 8 and 11 of a 4-week cycle. Patients were treated to their maximum response plus two additional cycles. The treatment regimen was discontinued after a maximum of eight cycles. Our modified schedule and dosing regimen achieved a high overall response rate of 86%, while showing a marked decrease in the incidence and severity of peripheral neuropathy, palmar-plantar erythrodysesthesia and myelosuppression compared to the standard dosing on a 3-week cycle using these drugs. This modified regimen of dexamethasone, bortezomib and PLD shows improved tolerability and safety while maintaining a high response rate when compared to standard treatment with these agents in the frontline setting.

Obinutuzumab plus CHOP is effective and has a tolerable safety profile in previously untreated, advanced diffuse large B-cell lymphoma: the phase II GATHER study.

This study investigated the safety and efficacy of obinutuzumab plus cyclophosphamide, doxorubicin, vincristine, and prednisone (G-CHOP) in patients with advanced diffuse large B-cell lymphoma (DLBCL) and explored the impact of cell-of-origin (COO) on patient outcomes. Patients (N = 100) received obinutuzumab (1000 mg on the days 1, 8, and 15 of cycle 1, and day 1 of cycles 2-8) plus CHOP (cycles 1-6). For patients without grade ≥3 infusion-related reactions (IRRs) to standard-rate obinutuzumab infusion, a shorter duration of infusion (SDI) was evaluated. Overall and complete response rates, as determined according to the Cheson et al. criteria by investigators/independent radiological facility, were 82.0/75.0% and 55.0/58.0%, respectively. SDI of 120 minutes and 90 minutes were well tolerated with no grade ≥3 IRRs. Among all patients, IRRs typically occurred during cycle 1, day 1. G-CHOP is active and has an acceptable safety profile in the first-line treatment of patients with advanced DLBCL. Clinical Trials: NCT01414855DLBCL.

Metabolic therapy with PEG-arginase induces a sustained complete remission in immunotherapy-resistant melanoma.

BACKGROUND: Metastatic melanoma is an aggressive skin cancer with a poor prognosis. Current treatment strategies for high-stage melanoma are based around the use of immunotherapy with immune checkpoint inhibitors such as anti-PDL1 or anti-CTLA4 antibodies to stimulate anti-cancer T cell responses, yet a number of patients will relapse and die of disease. Here, we report the first sustained complete remission in a patient with metastatic melanoma who failed two immunotherapy strategies, by targeting tumour arginine metabolism. CASE PRESENTATION: A 65-year-old patient with metastatic melanoma who progressed through two immunotherapy strategies with immune checkpoint inhibitor antibodies was enrolled in a phase I study (NCT02285101) and treated with 2 mg/kg intravenously, weekly pegylated recombinant arginase (BCT-100). The patient experienced no toxicities > grade 2 and entered a complete remission which is sustained for over 30 months. RNA-sequencing identified a number of transcriptomic pathway alterations compared to control samples. The tumour had absent expression of the recycling enzymes argininosuccinate synthetase (ASS) and ornithine transcarbamylase (OTC) indicating a state of arginine auxotrophy, which was reconfirmed by immunohistochemistry, and validation in a larger cohort of melanoma tumour samples. CONCLUSIONS: Targeting arginine metabolism with therapeutic arginase in arginine auxotrophic melanoma can be an effective salvage for the treatment of patients who fail immunotherapy.

A Phase 1 Study to Assess the Relative Bioavailability of Two Capsule Formulations of Ixazomib, an Oral Proteasome Inhibitor, in Patients With Advanced Solid Tumors or Lymphoma.

The oral proteasome inhibitor ixazomib is approved in multiple countries in combination with lenalidomide and dexamethasone for the treatment of patients with multiple myeloma who have received at least 1 prior therapy. Two oral capsule formulations of ixazomib have been used during clinical development. This randomized, 2-period, 2-sequence crossover study (Clinicaltrials.gov identifier NCT01454076) assessed the relative bioavailability of capsule B in reference to capsule A in adult patients with advanced solid tumors or lymphoma. The study was conducted in 2 parts. In cycle 1 (pharmacokinetic cycle), patients received a 4-mg dose of ixazomib as capsule A or capsule B on day 1, followed by a 4-mg dose of the alternate capsule formulation on day 15. Pharmacokinetic samples were collected over 216 hours postdose. After the pharmacokinetic cycle, patients could continue in the study and receive ixazomib (capsule B only) on days 1, 8, and 15 of each 28-day cycle. Twenty patients were enrolled; of these, 14 were included in the pharmacokinetic-evaluable population. Systemic exposures of ixazomib were similar after administration of capsule A or capsule B. The geometric least-squares mean ratios (capsule B versus capsule A) were 1.16 for Cmax (90% confidence interval [CI], 0.84-1.61) and 1.04 for AUC0-216 (90%CI, 0.91-1.18). The most frequently reported grade 3 drug-related adverse events were fatigue (15%) and nausea (10%); there were no grade 4 drug-related adverse events. These results support the combined analysis of data from studies that used either formulation of ixazomib during development.

Effects of Strong CYP3A Inhibition and Induction on the Pharmacokinetics of Ixazomib, an Oral Proteasome Inhibitor: Results of Drug-Drug Interaction Studies in Patients With Advanced Solid Tumors or Lymphoma and a Physiologically Based Pharmacokinetic Analysis.

At clinically relevant ixazomib concentrations, in vitro studies demonstrated that no specific cytochrome P450 (CYP) enzyme predominantly contributes to ixazomib metabolism. However, at higher than clinical concentrations, ixazomib was metabolized by multiple CYP isoforms, with the estimated relative contribution being highest for CYP3A at 42%. This multiarm phase 1 study (Clinicaltrials.gov identifier: NCT01454076) investigated the effect of the strong CYP3A inhibitors ketoconazole and clarithromycin and the strong CYP3A inducer rifampin on the pharmacokinetics of ixazomib. Eighty-eight patients were enrolled across the 3 drug-drug interaction studies; the ixazomib toxicity profile was consistent with previous studies. Ketoconazole and clarithromycin had no clinically meaningful effects on the pharmacokinetics of ixazomib. The geometric least-squares mean area under the plasma concentration-time curve from 0 to 264 hours postdose ratio (90%CI) with vs without ketoconazole coadministration was 1.09 (0.91-1.31) and was 1.11 (0.86-1.43) with vs without clarithromycin coadministration. Reduced plasma exposures of ixazomib were observed following coadministration with rifampin. Ixazomib area under the plasma concentration-time curve from time 0 to the time of the last quantifiable concentration was reduced by 74% (geometric least-squares mean ratio of 0.26 [90%CI 0.18-0.37]), and maximum observed plasma concentration was reduced by 54% (geometric least-squares mean ratio of 0.46 [90%CI 0.29-0.73]) in the presence of rifampin. The clinical drug-drug interaction study results were reconciled well by a physiologically based pharmacokinetic model that incorporated a minor contribution of CYP3A to overall ixazomib clearance and quantitatively considered the strength of induction of CYP3A and intestinal P-glycoprotein by rifampin. On the basis of these study results, the ixazomib prescribing information recommends that patients should avoid concomitant administration of strong CYP3A inducers with ixazomib.

Phase I study of the anti-α5ß1 monoclonal antibody MINT1526A with or without bevacizumab in patients with advanced solid tumors.

PURPOSE: MINT1526A is a monoclonal antibody that blocks the interaction of integrin alpha 5 beta 1 (α5ß1) with its extracellular matrix ligands. This phase I study evaluated the safety and pharmacokinetics of MINT1526A with or without bevacizumab in patients with advanced solid tumors. METHODS: MINT1526A was administered every 3 weeks (Q3W) as monotherapy (arm 1) or in combination with bevacizumab 15 mg/kg, Q3W (arm 2). Each arm included a 3 + 3 dose-escalation stage and a dose-expansion stage. RESULTS: Twenty-four patients were enrolled in arm 1 (dose range 2-30 mg/kg) and 30 patients were enrolled in arm 2 (dose range 3-15 mg/kg). Monocyte α5ß1 receptor occupancy was saturated at a dose of 15 mg/kg. No dose-limiting toxicities were observed, and the maximum tolerated dose was not reached in either arm. The most common adverse events, regardless of causality, included abdominal pain (25%), diarrhea (25%), nausea (21%), vomiting (21%), and fatigue (21%) in arm 1 and nausea (40%), fatigue (33%), vomiting (30%), dehydration (30%), headache (30%), and hypertension (30%) in arm 2. No grade ≥ 3 bleeding events were observed in either arm. No confirmed partial responses (PR) were observed in arm 1. In arm 2, one patient with thymic carcinoma experienced a confirmed PR and two patients with hepatocellular carcinoma (HCC) experienced durable minor radiographic responses. CONCLUSIONS: MINT1526A, with or without bevacizumab, was well-tolerated. Preliminary evidence of combination efficacy, including in patients with HCC, was observed, but cannot be distinguished from bevacizumab monotherapy in this phase I study.

A Multicenter, Open-Label, Phase 1b Study of Carfilzomib, Cyclophosphamide, and Dexamethasone in Newly Diagnosed Multiple Myeloma Patients (CHAMPION-2).

INTRODUCTION: This phase 1b study evaluated the safety and efficacy of 3 dose levels of carfilzomib when provided with fixed dose oral cyclophosphamide and dexamethasone (KCyd) in patients with newly diagnosed multiple myeloma (MM). PATIENTS AND METHODS: CHAMPION-2 was a multicenter single-arm study. Patients with newly diagnosed secretory MM were enrolled and received KCyd treatment for up to 8 cycles. A 3 + 3 dose escalation scheme was used to evaluate twice-weekly carfilzomib at 36, 45, and 56 mg/m2 dose levels, followed by a dose expansion. RESULTS: No dose-limiting toxicities were observed in any of the dose evaluation cohorts. The KCyd regimen that included the maximum planned carfilzomib dose of 56 mg/m2 twice weekly was brought forward into dose expansion. A total of 16 patients were treated at this dose level. At 56 mg/m2 the overall response rate was 87.5% (95% confidence interval, 61.7-98.4), and the median time to response of 14 patients whose disease responded to therapy was 1 month. At this dose level, common adverse events of grade 3 or higher were anemia (25.0%), neutropenia (18.8%), acute kidney injury (12.5%), and decreased white blood cell count (12.5%). Ten of 16 patients who received carfilzomib at 56 mg/m2 completed all 8 cycles, 5 patients discontinued study therapy before cycle 8 as a result of adverse events, and 1 patient discontinued therapy as a result of progressive disease. CONCLUSION: Carfilzomib in combination with cyclophosphamide and dexamethasone is effective and has manageable toxicity for patients with newly diagnosed MM.