CRISPR-Cas9 In Vivo Gene Editing of KLKB1 for Hereditary Angioedema.

BACKGROUND: Hereditary angioedema is a rare genetic disease that leads to severe and unpredictable swelling attacks. NTLA-2002 is an in vivo gene-editing therapy based on clustered regularly interspaced short palindromic repeats (CRISPR)-CRISPR-associated protein 9. NTLA-2002 targets the gene encoding kallikrein B1 (KLKB1), with the goal of lifelong control of angioedema attacks after a single dose. METHODS: In this phase 1 dose-escalation portion of a combined phase 1-2 trial of NTLA-2002 in adults with hereditary angioedema, we administered NTLA-2002 at a single dose of 25 mg, 50 mg, or 75 mg. The primary end points were the safety and side-effect profile of NTLA-2002 therapy. Secondary and exploratory end points included pharmacokinetics, pharmacodynamics, and clinical efficacy determined on the basis of investigator-confirmed angioedema attacks. RESULTS: Three patients received 25 mg of NTLA-2002, four received 50 mg, and three received 75 mg. At all dose levels, the most common adverse events were infusion-related reactions and fatigue. No dose-limiting toxic effects, serious adverse events, grade 3 or higher adverse events, or clinically important laboratory findings were observed after the administration of NTLA-2002. Dose-dependent reductions in the total plasma kallikrein protein level were observed between baseline and the latest assessment, with a mean percentage change of -67% in the 25-mg group, -84% in the 50-mg group, and -95% in the 75-mg group. The mean percentage change in the number of angioedema attacks per month between baseline and weeks 1 through 16 (primary observation period) was -91% in the 25-mg group, -97% in the 50-mg group, and -80% in the 75-mg group. Among all the patients, the mean percentage change in the number of angioedema attacks per month from baseline through the latest assessment was -95%. CONCLUSIONS: In this small study, a single dose of NTLA-2002 led to robust, dose-dependent, and durable reductions in total plasma kallikrein levels, and no severe adverse events were observed. In exploratory analyses, reductions in the number of angioedema attacks per month were observed at all dose levels. (Funded by Intellia Therapeutics; ClinicalTrials.gov number, NCT05120830.).

CRISPR-based gene disruption and integration of high-avidity, WT1-specific T cell receptors improve antitumor T cell function.

T cell receptor (TCR)-based therapy has the potential to induce durable clinical responses in patients with cancer by targeting intracellular tumor antigens with high sensitivity and by promoting T cell survival. However, the need for TCRs specific for shared oncogenic antigens and the need for manufacturing protocols able to redirect T cell specificity while preserving T cell fitness remain limiting factors. By longitudinal monitoring of T cell functionality and dynamics in 15 healthy donors, we isolated 19 TCRs specific for Wilms' tumor antigen 1 (WT1), which is overexpressed by several tumor types. TCRs recognized several peptides restricted by common human leukocyte antigen (HLA) alleles and displayed a wide range of functional avidities. We selected five high-avidity HLA-A*02:01-restricted TCRs, three that were specific to the less explored immunodominant WT137-45 and two that were specific to the noncanonical WT1-78-64 epitopes, both naturally processed by primary acute myeloid leukemia (AML) blasts. With CRISPR-Cas9 genome editing tools, we combined TCR-targeted integration into the TCR α constant (TRAC) locus with TCR ß constant (TRBC) knockout, thus avoiding TCRαß mispairing and maximizing TCR expression and function. The engineered lymphocytes were enriched in memory stem T cells. A unique WT137-45-specific TCR showed antigen-specific responses and efficiently killed AML blasts, acute lymphoblastic leukemia blasts, and glioblastoma cells in vitro and in vivo in the absence of off-tumor toxicity. T cells engineered to express this receptor are being advanced into clinical development for AML immunotherapy and represent a candidate therapy for other WT1-expressing tumors.

CRISPR-Cas9 In Vivo Gene Editing for Transthyretin Amyloidosis.

BACKGROUND: Transthyretin amyloidosis, also called ATTR amyloidosis, is a life-threatening disease characterized by progressive accumulation of misfolded transthyretin (TTR) protein in tissues, predominantly the nerves and heart. NTLA-2001 is an in vivo gene-editing therapeutic agent that is designed to treat ATTR amyloidosis by reducing the concentration of TTR in serum. It is based on the clustered regularly interspaced short palindromic repeats and associated Cas9 endonuclease (CRISPR-Cas9) system and comprises a lipid nanoparticle encapsulating messenger RNA for Cas9 protein and a single guide RNA targeting TTR. METHODS: After conducting preclinical in vitro and in vivo studies, we evaluated the safety and pharmacodynamic effects of single escalating doses of NTLA-2001 in six patients with hereditary ATTR amyloidosis with polyneuropathy, three in each of the two initial dose groups (0.1 mg per kilogram and 0.3 mg per kilogram), within an ongoing phase 1 clinical study. RESULTS: Preclinical studies showed durable knockout of TTR after a single dose. Serial assessments of safety during the first 28 days after infusion in patients revealed few adverse events, and those that did occur were mild in grade. Dose-dependent pharmacodynamic effects were observed. At day 28, the mean reduction from baseline in serum TTR protein concentration was 52% (range, 47 to 56) in the group that received a dose of 0.1 mg per kilogram and was 87% (range, 80 to 96) in the group that received a dose of 0.3 mg per kilogram. CONCLUSIONS: In a small group of patients with hereditary ATTR amyloidosis with polyneuropathy, administration of NTLA-2001 was associated with only mild adverse events and led to decreases in serum TTR protein concentrations through targeted knockout of TTR. (Funded by Intellia Therapeutics and Regeneron Pharmaceuticals; ClinicalTrials.gov number, NCT04601051.).

Breast Conservation After Neoadjuvant Chemotherapy for Triple-Negative Breast Cancer: Surgical Results From the BrighTNess Randomized Clinical Trial.

Importance: Neoadjuvant systemic therapy (NST) is often administered to enable breast-conserving therapy (BCT) in stages II to III breast cancer. Objectives: To prospectively evaluate the role of NST in conversion from BCT ineligibility to BCT eligibility and to assess the association of response to NST, germline BRCA (gBRCA) status, and region of treatment with surgical choice in women with triple-negative breast cancer (TNBC). Design, Setting, and Participants: This prespecified secondary analysis of a multicentered, phase 3, double-blind, randomized clinical trial (BrighTNess) enrolled 634 eligible women across 145 centers in 15 countries in North America, Europe, and Asia. Women with operable, clinical stages II to III TNBC who underwent gBRCA mutation testing before initiating NST were eligible to participate. Data were collected from April 1, 2014, to December 8, 2016. This preplanned analysis was performed from January 5, 2018, to October 28, 2019. Interventions: Study participants were randomized to receive 12 weeks of weekly paclitaxel alone or with the addition of carboplatin and/or veliparib, followed by 4 cycles of doxorubicin hydrochloride and cyclophosphamide. Main Outcomes and Measures: Surgeons assessed BCT candidacy by clinical and radiographic criteria before and after NST. Surgical choices and whether BCT eligibility was associated with the likelihood of pathologic complete response were then analyzed. Results: Among the 634 randomized patients (median age, 51 [range, 22-78] years), pre- and post-NST assessments were available for 604 patients. Of 141 patients deemed BCT ineligible at baseline, 75 (53.2%) converted to BCT eligible. Overall, 342 (68.1%) of 502 patients deemed BCT eligible after NST underwent BCT, including 42 (56.0%) of the 75 who converted to BCT eligible. Patients treated in Europe and Asia were more likely to undergo BCT (odds ratio, 2.66; 95% CI, 1.84-3.84) compared with those treated in North America. Among patients without gBRCA mutation undergoing mastectomy, those treated in North America were more likely to undergo contralateral prophylactic mastectomy (57 of 81 [70.4%] vs 6 of 30 [20.0%]; P < .001). Rates of pathologic complete response were similar between patients deemed BCT eligible at baseline and those who were BCT ineligible but converted to BCT eligibility after NST (55.3 [235 of 425] vs 49.3% [37 of 75]; P = .38). Conclusions and Relevance: This prospective analysis of NST and BCT eligibility in TNBC demonstrates a conversion from BCT ineligibility to BCT eligibility of 53.2%. Lower BCT rates among eligible patients and higher bilateral mastectomy rates among patients without gBRCA mutation in North America merit investigation. Trial Registration: ClinicalTrials.gov identifier: NCT02032277.

Safety and pharmacokinetics of veliparib extended-release in patients with advanced solid tumors: a phase I study.

The poly(ADP-ribose) polymerase-1/2 inhibitor veliparib is active against tumors deficient in homologous DNA damage repair. The pharmacokinetics and safety of veliparib extended-release (ER) were evaluated in patients with advanced solid tumors. This phase I study assessed veliparib-ER up to 800 mg once daily or 600 mg twice daily. Dose-limiting toxicities (DLTs), recommended phase II dose (RP2D), and maximum tolerated dose (MTD) were assessed in cycle 1 and safety/tolerability during continuous administration (28-day cycles). Seventy-one patients (n = 53 ovarian, n = 17 breast, n = 1 prostate carcinoma) received veliparib; 50 had deleterious breast cancer susceptibility (BRCA) gene mutations. Single-dose veliparib-ER 200 mg (fasting) led to 58% lower peak concentration and similar area under the concentration-time curve compared with veliparib immediate-release (IR). Three patients experienced DLTs (grade 2: asthenia; grade 3: nausea/vomiting, seizure). RP2D and MTD for veliparib-ER were 400 mg BID. The most frequent adverse events (AEs) were nausea (78.9%) and vomiting (50.7%). The most common grade 3/4 treatment-related AEs were as follows: thrombocytopenia (7.0%), nausea, and anemia (4.2% each). Overall, 12 (27.3%) patients with ovarian and 10 (62.5%) patients with breast carcinoma had a partial response. Veliparib-ER, versus veliparib-IR, exhibited an improved pharmacokinetic profile and was well tolerated in patients with ovarian and BRCA-mutated breast cancers.

Clinical pharmacodynamic/exposure characterisation of the multikinase inhibitor ilorasertib (ABT-348) in a phase 1 dose-escalation trial.

BACKGROUND: Ilorasertib (ABT-348) inhibits Aurora and VEGF receptor (VEGFR) kinases. Patients with advanced solid tumours participated in a phase 1 dose-escalation trial to profile the safety, tolerability, and pharmacokinetics of ilorasertib. METHODS: Ilorasertib monotherapy was administered at 10-180 mg orally once daily (Arm I, n = 23), 40-340 mg orally twice daily (Arm II, n = 28), or 8-32 mg intravenously once daily (Arm III, n = 7), on days 1, 8, and 15 of each 28-day cycle. RESULTS: Dose-limiting toxicities were predominantly related to VEGFR inhibition. The most frequent treatment-emergent adverse events ( > 30%) were: fatigue (48%), anorexia (34%), and hypertension (34%). Pharmacodynamic markers suggested that ilorasertib engaged VEGFR2 and Aurora B kinase, with the VEGFR2 effects reached at lower doses and exposures than Aurora inhibition effects. In Arm II, one basal cell carcinoma patient (40 mg twice daily (BID)) and one patient with adenocarcinoma of unknown primary site (230 mg BID) had partial responses. CONCLUSIONS: In patients with advanced solid tumours, ilorasertib treatment resulted in evidence of engagement of the intended targets and antitumour activity, but with maximum inhibition of VEGFR family kinases occurring at lower exposures than typically required for inhibition of Aurora B in tissue. CLINICAL TRIAL REGISTRATION: NCT01110486.

Addition of the PARP inhibitor veliparib plus carboplatin or carboplatin alone to standard neoadjuvant chemotherapy in triple-negative breast cancer (BrighTNess): a randomised, phase 3 trial.

BACKGROUND: Although several randomised trials in patients with triple-negative breast cancer have shown that the addition of carboplatin, with or without poly(ADP-ribose) polymerase (PARP) inhibitors, to neoadjuvant chemotherapy increases the likelihood of achieving a pathological complete response, the use of these therapies in this setting has remained controversial. The BrighTNess trial was designed to assess the addition of the PARP inhibitor veliparib plus carboplatin or carboplatin alone to standard neoadjuvant chemotherapy in triple-negative breast cancer. METHODS: We did a phase 3, randomised, double-blind, placebo-controlled trial (BrighTNess) across 145 sites in 15 countries. Patients aged 18 years and older with previously untreated histologically or cytologically confirmed clinical stage II-III triple-negative breast cancer, who were candidates for potentially curative surgery and had an Eastern Cooperative Oncology Group performance status of 0 or 1, were randomly assigned (2:1:1) by an interactive response technology system via permuted blocks (block size of four) within strata to receive one of three segment 1 regimens: paclitaxel (80 mg/m2 intravenously weekly for 12 doses) plus carboplatin (area under the curve 6 mg/mL per min, intravenously every 3 weeks, for four cycles) plus veliparib (50 mg orally, twice a day); paclitaxel plus carboplatin plus veliparib placebo (twice a day); or paclitaxel plus carboplatin placebo (every 3 weeks for four cycles) plus veliparib placebo. Following segment 1, all patients were assigned to segment 2 in which they received doxorubicin and cyclophosphamide every 2-3 weeks for four cycles. Randomisation for segment 1 was stratified by germline BRCA mutation status, nodal stage, and planned schedule of doxorubicin and cyclophosphamide administration. The primary endpoint was pathological complete response in breast and lymph nodes as determined by site pathologists following completion of neoadjuvant therapy. Efficacy analyses were done by intention to treat and safety analyses included all patients who received at least one dose of study treatment. These are the first results of an ongoing clinical trial; the data cutoff for the analyses presented was Dec 8, 2016. This study is registered with ClinicalTrials.gov, number NCT02032277. FINDINGS: Between April 4, 2014, and March 18, 2016, 634 patients were randomly assigned: 316 to paclitaxel plus carboplatin plus veliparib, 160 to paclitaxel plus carboplatin, and 158 to paclitaxel alone. The proportion of patients who achieved a pathological complete response was higher in the paclitaxel, carboplatin, and veliparib group than in patients receiving paclitaxel alone (168 [53%] of 316 patients vs 49 [31%] of 158, p<0·0001), but not compared with patients receiving paclitaxel plus carboplatin (92 [58%] of 160 patients, p=0·36). Grade 3 or 4 toxicities, and serious adverse events were more common in patients receiving carboplatin, whereas veliparib did not substantially increase toxicity. The most common grade 3 or 4 events overall were neutropenia (352 [56%] of 628 patients), anaemia (180 [29%]), and thrombocytopenia (75 [12%]) through complete treatment, and febrile neutropenia (88 [15%] of 601 patients) during segment 2. The most common serious adverse events were febrile neutropenia (80 [13%] of 628 patients) and anaemia (20 [3%]). INTERPRETATION: Although the addition of veliparib and carboplatin to paclitaxel followed by doxorubicin and cyclophosphamide improved the proportion of patients with triple-negative breast cancer who achieved a pathological complete response, the addition of veliparib to carboplatin and paclitaxel did not. Increased toxicities with the addition of carboplatin (with or without veliparib) to paclitaxel were manageable and did not substantially affect treatment delivery of paclitaxel followed by doxorubicin and cyclophosphamide. Given the consistent results with previous studies, the addition of carboplatin appears to have a favourable risk to benefit profile and might be considered as a potential component of neoadjuvant chemotherapy for patients with high-risk, triple-negative breast cancer. FUNDING: AbbVie.

Phase I combination study of the PARP inhibitor veliparib plus carboplatin and gemcitabine in patients with advanced ovarian cancer and other solid malignancies.

OBJECTIVE: Determine the maximum tolerated dose (MTD) and recommended phase II dose (RP2D) of veliparib combined with carboplatin and gemcitabine in patients with advanced ovarian cancer and other nonhematologic malignancies. METHODS: In this phase I study, patients with metastatic or unresectable solid tumors and ≤2 prior chemotherapy regimens received veliparib combined with carboplatin area under the curve (AUC) 4 on day 1 and gemcitabine 800mg/m2 on days 1 and 8 of a 21-day cycle for maximum 10cycles, followed by optional veliparib maintenance therapy. Veliparib dosing commenced twice-daily (BID) continuously on day 1 of cycle 2; granulocyte colony-stimulating factor was permitted. Dose escalation used a Bayesian continual reassessment method. Safety, tolerability, and efficacy were evaluated. RESULTS: Seventy-five patients were enrolled (ovarian cancer, n=54; breast cancer, n=12). Thirty-six patients with ovarian cancer (67%) had known germline BRCA mutations. Most common treatment-related adverse events (TRAEs; ≥60%) were thrombocytopenia, neutropenia, nausea, and anemia. Most common grade 3/4 TRAEs (≥40%) were neutropenia and thrombocytopenia. Dose-limiting toxicities were thrombocytopenia and neutropenia. The MTD/RP2D was established at veliparib 250mg with carboplatin AUC 4 plus gemcitabine 800mg/m2. Responses were observed in 69% of patients with BRCA-deficient ovarian cancer (45% partial, 24% complete responses). Five patients remained on veliparib (80-310mg BID) for >34cycles. CONCLUSIONS: Veliparib plus carboplatin/gemcitabine is tolerated, with a safety profile similar to carboplatin and gemcitabine alone. Combination therapy demonstrated promising preliminary antitumor activity in platinum-sensitive ovarian cancer patients with germline BRCA mutations. Trial registration ID: NCT01063816.

Safety, pharmacokinetics, and pharmacodynamics of oral omaveloxolone (RTA 408), a synthetic triterpenoid, in a first-in-human trial of patients with advanced solid tumors.

BACKGROUND: Omaveloxolone is a semisynthetic oleanane triterpenoid that potently activates Nrf2 with subsequent antioxidant function. We conducted a first-in-human Phase I clinical trial (NCT02029729) with the primary objectives to determine the appropriate dose for Phase II studies, characterize pharmacokinetic and pharmacodynamic parameters, and assess antitumor activity. METHODS: Omaveloxolone was administered orally once daily continuously in a 28-day cycle for patients with stage 4 relapsed/refractory melanoma or non-small cell lung cancer. An accelerated titration design was employed until a grade 2-related adverse event (AE) occurred. A standard 3+3 dose escalation was employed. Single-dose and steady-state plasma pharmacokinetics of the drug were characterized. Downstream Nrf2 activation was assessed in peripheral blood mononuclear cells by quantification of target gene mRNA expression. RESULTS: Omaveloxolone was tested at four dose levels up to 15 mg given orally once daily. No dose-limiting toxicities were detected, and the maximum tolerated dose was not determined. All drug-related AEs were either grade 1 or 2 in severity, and none required clinical action. The most common drug-related AEs were elevated alkaline phosphatase (18%) and anemia (18%). No drug interruptions or reductions were required. Omaveloxolone was rapidly absorbed and exhibited proportional increases in exposure across dose levels. With some exceptions, an overall trend toward time-dependent and dose-dependent activation of Nrf2 antioxidant genes was observed. No confirmed radiologic responses were seen, although one lung cancer subject did have stable disease exceeding 1 year. CONCLUSIONS: Omaveloxolone has favorable tolerability at biologically active doses, although this trial had a small sample size which limits definitive conclusions. These findings support further investigation of omaveloxolone in cancer.

Smoking History Predicts Sensitivity to PARP Inhibitor Veliparib in Patients with Advanced Non-Small Cell Lung Cancer.

INTRODUCTION: Tobacco-related NSCLC is associated with reduced survival and greater genomic instability. Veliparib, a potent poly(adenosine diphosphate-ribose) polymerase inhibitor, augments platinum-induced DNA damage. A phase 2 trial of untreated advanced NSCLC showed a trend for improved outcomes (hazard ratio [HR] = 0.80, 95% confidence interval: 0.54-1.18, p = 0.27 for overall survival and HR = 0.72, 95% CI: 0.45-1.15, p = 0.17 for progression-free survival) when veliparib was added to carboplatin/paclitaxel. Here we report an exploratory analysis by smoking history. METHODS: Patients were randomized 2:1 to receive carboplatin/paclitaxel with veliparib, 120 mg (n = 105), or placebo (n = 53). Patients were stratified by histologic subtype and smoking history (recent smokers [n = 95], former smokers [n = 42], and never-smokers [n = 21]). Plasma cotinine level was measured as a chemical index of smoking. Mutation status was assessed by whole exome sequencing (n = 38). RESULTS: Smoking history, histologic subtype, age, Eastern Cooperative Oncology Group performance status, sex, and geographic region predicted veliparib benefit in univariate analyses. In multivariate analysis, history of recent smoking was most predictive for veliparib benefit. Recent smokers treated with veliparib derived significantly greater progression-free survival and overall survival benefits (HR = 0.38 [p < 0.01] and HR = 0.43 [p < 0.01]) than former smokers (HR = 2.098 [p = 0 0208] and HR = 1.62 [p = 0.236]) and never-smokers (HR = 1.025 [p = 0.971] and HR = 1.33 [p = 0.638]). Sequencing data revealed that mutational burden was not associated with veliparib benefit. The rate of grade 3 or 4 adverse events was higher in recent smokers with veliparib treatment; all-grade and serious adverse events were similar in both treatment arms. CONCLUSIONS: Smoking history predicted for efficacy with a veliparib-chemotherapy combination; toxicity was acceptable regardless of smoking history. A prespecified analysis of recent smokers is planned for ongoing phase 3 studies of veliparib in NSCLC.

Randomized, Placebo-Controlled, Phase II Study of Veliparib in Combination with Carboplatin and Paclitaxel for Advanced/Metastatic Non-Small Cell Lung Cancer.

Purpose: PARP plays an important role in DNA repair. Veliparib, a PARP inhibitor, enhances the efficacy of platinum compounds and has been safely combined with carboplatin and paclitaxel. The primary endpoint of this phase II trial determined whether addition of veliparib to carboplatin and paclitaxel improved progression-free survival (PFS) in previously untreated patients with advanced/metastatic non-small cell lung cancer.Experimental Design: Patients were randomized 2:1 to carboplatin and paclitaxel with either veliparib or placebo. Veliparib (120 mg) or placebo was given on days 1 to 7 of each 3-week cycle, with carboplatin (AUC = 6 mg/mL/min) and paclitaxel (200 mg/m2) administered on day 3, for a maximum of 6 cycles.Results: Overall, 158 were included (median age, 63 years; male 68%, squamous histology 48%). Median PFS was 5.8 months in the veliparib group versus 4.2 months in the placebo group [HR, 0.72; 95% confidence interval (CI), 0.45-1.15; P = 0.17)]. Median overall survival (OS) was 11.7 and 9.1 months in the veliparib and placebo groups, respectively (HR, 0.80; 95% CI, 0.54-1.18; P = 0.27). In patients with squamous histology, median PFS (HR, 0.54; 95% CI, 0.26-1.12; P = 0.098) and OS (HR, 0.73; 95% CI, 0.43-1.24; P = 0.24) favored veliparib treatment. Objective response rate was similar between groups (veliparib: 32.4%; placebo: 32.1%), but duration of response favored veliparib treatment (HR, 0.47; 95% CI, 0.16-1.42; P = 0.18). Grade III/IV neutropenia, thrombocytopenia, and anemia were comparable between groups.Conclusions: Veliparib combination with carboplatin and paclitaxel was well-tolerated and demonstrated a favorable trend in PFS and OS versus chemotherapy alone. Patients with squamous histology had the best outcomes with veliparib combination. Clin Cancer Res; 23(8); 1937-44. ©2016 AACR.

Plasma biomarker signature associated with improved survival in advanced non-small cell lung cancer patients on linifanib.

OBJECTIVES: Linifanib, a potent and selective inhibitor of the tyrosine kinase activity of vascular endothelial growth factor and platelet-derived growth factor receptors, has clinical activity in advanced non-small cell lung cancer (NSCLC) both as monotherapy in the relapsed setting or with carboplatin and paclitaxel in the first-line setting. Though benefit was observed in unselected patient populations, identification of predictive biomarkers is critical for further development of this novel agent. MATERIALS AND METHODS: Data from 4 randomized studies in relapsed NSCLC with linifanib (n=116) or other treatments (n=125) were examined in an exploratory analysis to identify a biomarker profile predictive of favorable survival. RESULTS: A signature combining the established tumor markers carcinoembryonic antigen (CEA) and cytokeratin 19 fragments (CYFRA 21-1) was predictive of a favorable outcome. This signature was associated with improved survival in patients receiving linifanib monotherapy (hazard ratio [HR]=0.51 vs signature negative; p=0.002), but not in those receiving other anti-cancer treatments (p=0.716). This signature was validated on baseline plasma samples from patients enrolled in a randomized trial of daily linifanib 7.5 mg, linifanib 12.5 mg, or placebo added to first-line carboplatin and paclitaxel chemotherapy for advanced, nonsquamous NSCLC. Only linifanib-treated signature-positive patients had significant improvement in progression-free survival (PFS). Median PFS with placebo was 5.2 months versus 10.2 months (HR=0.49, p=0.049) for those receiving linifanib 7.5mg, and 8.3 months (HR=0.38, p=0.029) for linifanib 12.5 mg. Overall survival for signature-positive patients was 11.3 months with placebo, 12.5 months with linifanib 7.5mg (HR=1.02, p=0.758), and 17.4 months with linifanib 12.5 mg (HR=0.54, p=0.137). CONCLUSION: This baseline plasma biomarker signature is associated with improved outcome in advanced NSCLC patients receiving linifanib. Utility of the biomarker signature in patient selection for linifanib therapy in NSCLC merits evaluation in larger, prospective trials that are powered to detect a survival benefit.

Phase 1 dose escalation trial of ilorasertib, a dual Aurora/VEGF receptor kinase inhibitor, in patients with hematologic malignancies.

BACKGROUND: Ilorasertib (ABT-348) is a novel inhibitor of Aurora kinase, vascular endothelial growth factor (VEGF) and platelet-derived growth factor receptors, and the Src families of tyrosine kinases. Ilorasertib alone or in combination with azacitidine demonstrated activity in preclinical models in various hematological malignancies, indicating that pan-Aurora kinase and multiple kinase inhibition may have preferential antileukemic activity. This phase 1 trial determined the safety, pharmacokinetics, and preliminary antitumor activity of ilorasertib alone or combined with azacitidine in advanced hematologic malignancies. PATIENTS AND METHODS: Fifty-two patients (median age, 67 years; 35 % with >4 prior regimens) with acute myelogenous leukaemia (AML; n = 38), myelodysplastic syndrome (n = 12), or chronic myelomonocytic leukaemia (n = 2) received 3 or 6 doses of ilorasertib per 28-day cycle and were assigned to arm A (once-weekly oral), B (twice-weekly oral), C (once-weekly oral plus azacitidine), or D (once-weekly intravenous) treatment. RESULTS: Maximum tolerated doses were not determined; the recommended phase 2 oral monotherapy doses were 540 mg once weekly and 480 mg twice weekly. The most common grade 3/4 adverse events were hypertension (28.8 %), hypokalemia (15.4 %), anemia (13.5 %), and hypophosphatemia (11.5 %). Oral ilorasertib pharmacokinetics appeared dose proportional, with a 15-hour half-life and no interaction with azacitidine. Ilorasertib inhibited biomarkers for Aurora kinase and VEGF receptors, and demonstrated clinical responses in 3 AML patients. CONCLUSIONS: Ilorasertib exhibited acceptable safety and pharmacokinetics at or below the recommended phase 2 dose, displayed evidence of dual Aurora kinase and VEGF receptor kinase inhibition, and activity in AML.

Randomized phase II study of carboplatin and paclitaxel with either linifanib or placebo for advanced nonsquamous non-small-cell lung cancer.

PURPOSE: Linifanib, a potent, selective inhibitor of vascular endothelial growth factor (VEGF) and platelet-derived growth factor (PDGF) receptors, has single-agent activity in non-small-cell lung cancer (NSCLC). We evaluated linifanib with carboplatin and paclitaxel as first-line therapy of advanced nonsquamous NSCLC. PATIENTS AND METHODS: Patients with stage IIIB/IV nonsquamous NSCLC were randomly assigned to 3-week cycles of carboplatin (area under the curve 6) and paclitaxel (200 mg/m(2)) with daily placebo (arm A), linifanib 7.5 mg (arm B), or linifanib 12.5 mg (arm C). The primary end point was progression-free survival (PFS); secondary efficacy end points included overall survival (OS) and objective response rate. RESULTS: One hundred thirty-eight patients were randomly assigned (median age, 61 years; 57% men; 84% smokers). Median PFS times were 5.4 months (95% CI, 4.2 to 5.7 months) in arm A (n = 47), 8.3 months (95% CI, 4.2 to 10.8 months) in arm B (n = 44), and 7.3 months (95% CI, 4.6 to 10.8 months) in arm C (n = 47). Hazard ratios (HRs) for PFS were 0.51 for arm B versus A (P = .022) and 0.64 for arm C versus A (P = .118). Median OS times were 11.3, 11.4, and 13.0 months in arms A, B, and C, respectively. HRs for OS were 1.08 for arm B versus A (P = .779) and 0.88 for arm C versus A (P = .650). Both linifanib doses were associated with increased toxicity, including a higher incidence of adverse events known to be associated with VEGF/PDGF inhibition. Baseline plasma carcinoembryonic antigen/cytokeratin 19 fragments biomarker signature was associated with PFS improvement and a trend toward OS improvement with linifanib 12.5 mg. CONCLUSION: Addition of linifanib to chemotherapy significantly improved PFS (arm B), with a modest trend for survival benefit (arm C) and increased toxicity reflective of known VEGF/PDGF inhibitory effects.

Linifanib versus Sorafenib in patients with advanced hepatocellular carcinoma: results of a randomized phase III trial.

PURPOSE: This open-label phase III trial evaluated efficacy and tolerability of linifanib versus sorafenib in patients with advanced hepatocellular carcinoma (HCC) without prior systemic therapy. PATIENTS AND METHODS: Patients were randomly assigned in a 1:1 ratio to linifanib 17.5 mg once daily or sorafenib 400 mg twice daily. Patients were stratified by region (Outside Asia, Japan, and rest of Asia), Eastern Cooperative Oncology Group performance score (ECOG PS; 0 or 1), vascular invasion or extrahepatic spread (yes or no), and hepatitis B virus (HBV) infection (yes or no). The primary end point of the study was overall survival (OS). Secondary end points were time to progression (TTP) and objective response rate (ORR) per RECIST v1.1. RESULTS: We randomly assigned 1,035 patients (median age, 60 years; Asian, 66.6%; ECOG PS 0, 65.2%; HBV, 49.1%; vascular invasion or extrahepatic spread, 70.1%). Median OS was 9.1 months on the linifanib arm (95% CI, 8.1 to 10.2) and 9.8 months on the sorafenib arm (95% CI, 8.3 to 11.0; hazard ratio [HR], 1.046; 95% CI, 0.896 to 1.221). For prespecified stratification subgroups, OS HRs ranged from 0.793 to 1.119 and the 95% CI contained 1.0. Median TTP was 5.4 months on the linifanib arm (95% CI, 4.2 to 5.6) and 4.0 months on the sorafenib arm (95% CI, 2.8 to 4.2; HR, 0.759; 95% CI, 0.643 to 0.895; P = .001). Best response rate was 13.0% on the linifanib arm versus 6.9% on the sorafenib arm. Grade 3/4 adverse events (AEs); serious AEs; and AEs leading to discontinuation, dose interruption, and reduction were more frequent with linifanib (all P < .001). CONCLUSION: Linifanib and sorafenib had similar OS in advanced HCC. Predefined superiority and noninferiority OS boundaries were not met for linifanib and the study failed to meet the primary end point. TTP and ORR favored linifanib; safety results favored sorafenib.

Randomized phase II open-label study of mFOLFOX6 in combination with linifanib or bevacizumab for metastatic colorectal cancer.

BACKGROUND: Although CRC is the third most commonly diagnosed cancer in the United States, second-line CRC treatment is limited. In this trial we examined the efficacy and safety of linifanib, an oral, potent, selective tyrosine kinase inhibitor of vascular endothelial growth factor and platelet-derived growth factor receptor families, with mFOLFOX6, compared with bevacizumab and mFOLFOX6, in previously treated metastatic CRC. PATIENTS AND METHODS: One hundred forty-eight patients with advanced CRC previously treated with fluoropyrimidine or irinotecan received bevacizumab (10 mg/kg, intravenous), low-dose linifanib (7.5 mg), or high-dose linifanib (12.5 mg), with mFOLFOX6. The primary end point was progression-free survival (PFS). Secondary objectives included overall survival (OS), objective response rate (ORR), and safety. RESULTS: No statistically significant differences in PFS occurred between bevacizumab and linifanib doses (low, hazard ratio [HR], 1.453 [95% confidence interval [CI], 0.830-2.539]; high, HR, 1.257 [95% CI, 0.672-2.351]). Median OS values were similar for bevacizumab and high-dose linifanib (bevacizumab, 16.5 months [95% CI, 13.0-not available]; high-dose linifanib, 16.4 months [95% CI, 11.9-21.7]; low-dose linifanib, 12.0 months [95% CI, 10.1-13.0]). ORRs were similar (bevacizumab, 34.7% [95% CI, 21.7-49.6]; low-dose linifanib, 24.0% [95% CI, 13.1-38.2]; high-dose linifanib, 22.4% [95% CI, 11.8-36.6]). Median cycles of 5-fluorouracil were reduced in the linifanib arms, versus the bevacizumab arm. Grade 3/4 adverse event occurrences were more frequent with linifanib. Palmar-plantar erythrodysesthesia, hypothyroidism, and thrombocytopenia were more common with high-dose linifanib than bevacizumab. CONCLUSION: Combining linifanib with mFOLFOX6 as a second-line treatment for metastatic CRC did not improve PFS, radiographic findings, or duration of response versus bevacizumab and mFOLFOX6.

A phase 1 study of linifanib in combination with carboplatin/paclitaxel as first-line treatment of Japanese patients with advanced or metastatic non-small cell lung cancer (NSCLC).

INTRODUCTION: Linifanib is a potent, orally active, and selective inhibitor of vascular endothelial growth factor and platelet-derived growth factor receptor kinase activities with clinical efficacy in non-small cell lung cancer (NSCLC). This phase 1 dose-escalation study evaluated the pharmacokinetics, safety, and efficacy of linifanib in combination with carboplatin/paclitaxel in Japanese patients with advanced NSCLC. METHODS: Carboplatin (AUC = 6 mg/mL/min) and paclitaxel (200 mg/m²) were administered on day 1 of each 21-day cycle up to a maximum of six cycles. Oral linifanib (7.5 mg) was given to six patients once daily throughout all cycles and escalated to 12.5 mg/day in a second cohort of six patients. RESULTS: Twelve patients received at least one dose of linifanib. The most common adverse events were hematologic and consistent with expected toxicities with carboplatin/paclitaxel. With 12.5 mg linifanib, grade 3/4 neutropenia, leukopenia, and thrombocytopenia occurred in 100, 83, and 83 % of patients, respectively. Dose-limiting grade 4 thrombocytopenia occurred in one patient at each dose level. Linifanib pharmacokinetics was similar to that in non-Japanese patients. At 12.5 mg, linifanib Cmax was 0.32 µg/mL and AUC24 was 4.29 µg h/mL. Linifanib Cmax occurred at 2-3 h with both doses and when given alone or in combination with carboplatin/paclitaxel. Exposure to linifanib appeared to be increased by carboplatin/paclitaxel, and exposure to paclitaxel appeared to be increased by linifanib. Partial responses were observed in nine patients. CONCLUSIONS: Linifanib added to carboplatin/paclitaxel is well tolerated in Japanese patients with advanced/metastatic NSCLC. The recommended dose of linifanib with carboplatin/paclitaxel is 12.5 mg, same as for US patients.

An open-label, phase 1 study evaluating safety, tolerability, and pharmacokinetics of linifanib (ABT-869) in Japanese patients with solid tumors.

PURPOSE: This phase 1 study assessed the safety, tolerability, pharmacokinetics, and preliminary antitumor activity of linifanib in Japanese patients with advanced solid tumors. METHODS: Patients were assigned to one of four sequential cohorts (0.05, 0.10, 0.20, or 0.25 mg/kg) of oral, once-daily linifanib on a 21-day cycle. Adverse events (AEs) were assessed per common terminology criteria for adverse events v3.0; tumor responses were assessed by response evaluation criteria in solid tumors. RESULTS: Eighteen patients were enrolled. Eleven (61%) received ≥3 prior therapies. Dose-limiting toxicities were Grade 3 ALT increase (0.10 mg/kg linifanib) and Grade 1 T-wave inversion (0.25 mg/kg linifanib) requiring dose interruption for >7 days and discontinuation on day 29. The most common linifanib-related AE was hypertension. Other significant treatment-related AEs included proteinuria, fatigue, and palmar-plantar erythrodysaesthesia. Linifanib pharmacokinetics were dose-proportional across 0.10-0.25 mg/kg. Two patients (11.1%) had confirmed partial responses, 12 had a best response of stable disease (11 had stable disease for ≥12 weeks), and four patients were not evaluable due to incomplete data. Four patients (lung cancer, breast cancer, thymic cancer, sarcoma) have continued linifanib for ≥48 weeks (range, 48-96+ weeks). CONCLUSION: Linifanib was well tolerated with promising preliminary clinical activity in Japanese patients. Later-phase global studies examining linifanib efficacy will include Japanese patients.

Monobenzyl ether of hydroquinone and 4-tertiary butyl phenol activate markedly different physiological responses in melanocytes: relevance to skin depigmentation.

Monobenzyl ether of hydroquinone (MBEH) is a Food and Drug Administration approved drug used for depigmentation therapy of advanced vitiligo. Here, the working mechanism of MBEH is explored in comparison to 4-tertiary butyl phenol (4-TBP), a known causative agent for occupational vitiligo mediating apoptotic melanocytic death. Cytotoxic experiments reveal that similar to 4-TBP, MBEH induces specific melanocyte death. To compare death pathways initiated by 4-TBP and MBEH, classical apoptotic hallmarks were evaluated in treated melanocytes. MBEH induced cell death without activating the caspase cascade or DNA fragmentation, showing that the death pathway is non-apoptotic. Release of High Mobility Group Box-1 protein by MBEH-treated melanocytes and ultrastructural features further confirmed a necrotic death pathway mediated by MBEH. A negative correlation between MBEH-induced cell death and cellular melanin content supports a cytoprotective role for melanin. Moreover, MBEH exposure upregulated the levels of melanogenic enzymes in cultured melanocytes and skin explants, whereas 4-TBP reduced the expression of the same. In summary, exposure to MBEH or 4-TBP has profoundly different consequences for melanocyte physiology and activates different death pathways. As the mode of cell death defines the nature of the immune response that follows, these findings help to explain the relative efficacy of these agents in mediating depigmentation.