Hematologic improvements with ivosidenib + azacitidine compared to placebo + azacitidine in patients with newly diagnosed acute myeloid leukemia

7042

Background: Ivosidenib (IVO) is a potent oral targeted inhibitor of mutant isocitrate dehydrogenase 1 (mIDH1). IVO plus azacitidine (AZA) significantly improved event-free survival (EFS), overall survival and complete remission + partial hematologic recovery rates compared with placebo (PBO) + AZA, in patients (pts) with newly diagnosed IDH1-mutant acute myeloid leukemia (AML) in the Phase 3 AGILE trial (NCT03173248). Here we report blood count recovery results from the AGILE trial. Methods: Pts were randomized 1:1 to IVO 500 mg QD + AZA 75 mg/m2 SC or IV for 7 days in 28-day cycles (n = 72), or PBO+AZA (n = 74). Red blood cell (RBC)/platelet transfusion history were assessed at screening and follow-up. Bone marrow (BM) and peripheral blood samples were obtained at screening, and during weeks 9, 17, 25, 33, 41, 53, and every 24 weeks thereafter, and at end of treatment and during EFS follow up. Samples were analyzed at each local site according to ICSH guidelines. Results: In the IVO+AZA and PBO+AZA arms, 4.2% and 5.5% of pts, respectively, received concomitant granulocyte colony-stimulating factor. Hemoglobin levels steadily increased from baseline at a similar rate in both treatment arms. Mean platelet count recovered from baseline values in the IVO+AZA and PBO+AZA arms (71.0 and 92.6 x 109/L, respectively) as early as week 9 of treatment (171.1 and 155.1 x 109/L, respectively) and continued to steadily increase thereafter in the treated population. In pts receiving IVO+AZA, mean neutrophil counts rapidly increased from baseline (0.99 x 109/L) to week 2 (2.05 x 109/L) and week 5 (4.07 x 109/L), and then generally stabilized to within the normal range to study end (last available cycle value; ̃2.0 x 109/L). Mean neutrophil counts initially declined with PBO+AZA before slowly recovering to near-normal levels after 36-40 weeks. The increased blood counts were accompanied by a rapid decrease in the mean BM blast percentage from 54.8% at baseline to 12.0% and 7.2% at week 9 and 17, respectively, in IVO+AZA treated patients and were maintained for 149 weeks. The decline in BM blasts was slower in the PBO+AZA arm (53.7%, 34.6% and 19.6% at baseline, week 9 and week 17, respectively). Among patients who were RBC/platelet transfusion-dependent at baseline (̃54.0% in both groups), 46.2% in the IVO+AZA group achieved RBC/platelet transfusion independence compared with 17.5% in the PBO+AZA arm (1-sided p = 0.0032). Additionally, fewer adverse events of febrile neutropenia (28.2% vs 34.2%) and infections (28.2% vs 49.3%) were reported in the IVO+AZA arm compared to the PBO+AZA arm. Conclusions: IVO+AZA demonstrated a significant clinical benefit compared with PBO+AZA and this sub-analysis demonstrated a rapidly improved recovery of blood counts and a reduced dependence on RBC and/or platelet transfusion. Moreover, rates of febrile neutropenia and infections were reduced with IVO+AZA. Clinical trial information: NCT03173248.

Changes in health-related quality of life in patients with newly diagnosed acute myeloid leukemia receiving ivosidenib + azacitidine or placebo + azacitidine

e19024

Background: Ivosidenib (IVO) is a potent, targeted inhibitor of mutant isocitrate dehydrogenase 1 (mIDH1) that is approved for acute myeloid leukemia (AML). IVO plus azacitidine (AZA) demonstrated clinical benefit compared with placebo (PBO) and AZA in the AGILE study (NCT03173248), and here we report the impact of IVO+AZA versus PBO+AZA on health-related quality of life (HRQoL). Methods: In the double-blind, PBO-controlled phase 3 AGILE study, patients (pts) were randomized 1:1 to IVO 500 mg QD + AZA 75 mg/m2 SC or IV for 7 days in 28-day cycles, or PBO+AZA. HRQoL was a secondary endpoint assessed using two validated questionnaires: the European Organisation of Research and Treatment of Cancer Core Quality of Life Questionnaire (EORTC QLQ-C30) and the EuroQol 5-dimension 5-level questionnaire (EQ-5D-5L). Questionnaires were administered pre-dose on cycle (C) 1 Day (D) 1, on C1D15, C2D1, C2D15, and on D1 of every odd cycle thereafter until the end of treatment. Score change from baseline across visits for all subscales of EORTC QLQ-C30 was analyzed with mixed models. A 10-point threshold in EORTC QLQ-C30 subscale score was used to evaluate clinically meaningful changes from baseline or differences between arms. Two-sided nominal p-values are reported. Results: At baseline, 69 and 68 pts out of 72 receiving IVO+AZA completed the EORTC QLQ-C30 and EQ-5D-5L, respectively, and 66 pts out of 74 receiving PBO+AZA completed both. Mean baseline HRQoL scores were similar between treatment arms. There was an initial decline in HRQoL (EORTC QLQ-C30 global health status [GHS/QoL]) in both arms for ̃4 months, consistent with time to response, and which was generally not clinically meaningful. IVO+AZA was associated with preserved or improved HRQoL compared to baseline for most subscales of the EORTC QLQ-C30 from C5 to C19 (after which no PBO+AZA HRQoL data were available), and at most timepoints for EQ-5D-5L VAS scores and index values. EORTC QLQ-C30 subscales with clinically meaningful improvements from baseline at most timepoints from C5 to C19 in the IVO+AZA arm included GHS/QoL, fatigue, pain and appetite loss. In contrast, there were few clinically meaningful improvements from baseline in PBO+AZA pts. GHS/QoL scores were significantly improved (p≤0.05) for IVO+AZA versus PBO+AZA at C2D1, C2D15, C7 and C9, and differences were clinically meaningful at C2D1 (10.2 point difference), C2D15 (10.1), C7 (12.6), C9 (22.6), C13 (14.9), C15 (15.4) and C19 (19.2). Likewise, improvements in EORTC QLQ-C30 fatigue, appetite loss, nausea and vomiting, diarrhea, cognitive functioning and social functioning favored IVO+AZA over PBO+AZA at multiple timepoints. Conclusions: Data from the AGILE study show that patients with mIDH1 AML receiving treatment with IVO+AZA tended to report maintenance or improved HRQoL from cycle 5 through to cycle 19 compared with PBO+AZA. Clinical trial information: NCT03173248.

Molecular characterization of clinical response in patients with newly diagnosed acute myeloid leukemia treated with ivosidenib + azacitidine compared to placebo + azacitidine

7019

Background: Acute myeloid leukemia (AML) is a disease with a dynamic mutational landscape; 6–10% of patients (pts) have somatic mutations in isocitrate dehydrogenase 1 ( IDH1), which can drive oncogenesis. Ivosidenib (IVO) is a potent oral targeted inhibitor of mutant IDH1 (mIDH1). IVO 500 mg QD + azacitidine (AZA) 75 mg/m2 SC or IV for 7 days in 28-day cycles was shown to significantly improve event-free survival (HR = 0.33 [95% CI 0.16, 0.69], p = 0.0011), median overall survival (24.0 vs 7.9 months), and complete remission + partial hematologic recovery rates (CR/CRh; 52.8% vs 17.6%) vs placebo (PBO) + AZA in the double-blind phase 3 AGILE study (NCT03173248) in pts with newly diagnosed IDH1-mutated AML (ND-AML). IDH1-mutation clearance ( IDH1-MC) and baseline co-mutation analysis from AGILE is reported. Methods: Genomic DNA from bone marrow mononuclear cells (BMMCs) or peripheral blood mononuclear cells (PBMCs), and/or bone marrow aspirate (BMA) were used for molecular studies. IDH1-MC analysis on BMMCs was performed by BEAMing digital PCR (limit of detection 0.02%-0.04%). BMA, BMMCs and PBMCs were utilized for co-mutational analysis by next-generation sequencing, ACE Extended Cancer Panel (detection limit 2%). Results: 146 pts were randomized: 72 to IVO+AZA; 74 to PBO+AZA. Median (range) baseline m IDH1 variant allele frequency in BMMCs was 36.7% (3.1–50.5) in the IVO+AZA arm and 35.5% (3.0–48.6) in the PBO+AZA arm. Updated IDH1-MC data (October 2021) from 47 IVO+AZA and 32 PBO+AZA treated pts with at least 1 on-treatment sample demonstrated IDH1-MC in 21/35 (60%) IVO+AZA pts achieving CR/CRh vs 4/11 (36%) PBO+AZA pts. In CR/CRh pts with time points available after IDH1-MC, suppression of the m IDH1 was durable and IDH1-MC maintained in all subsequent samples in 17/17 (100%) IVO+AZA treated pts and 1/3 (33%) PBO+AZA pts. Further analysis of baseline co-mutations on 120 pts (IVO+AZA: n = 58; PBO+AZA: n = 62) showed that DNMT3A, SRSF2, and RUNX1 were the most frequent in both treatment arms. Importantly, comparison of CR/CRh and non CR/CRh responses by cohort did not identify any single gene or pathway associated with an inferior outcome in IVO+AZA pts compared to PBO+AZA pts (p < 0.05, Fisher’s Exact test). Several genes ( DNMT3A, RUNX1, SRSF2, STAG2) and pathways (Differentiation, Epigenetics, Splicing) were associated with improved outcomes with IVO+AZA, including the RTK pathway, which was previously reported to be associated with primary resistance to IVO monotherapy. Further analysis of patient subgroups, including R132 variants (i.e., R132C vs R132S), will be presented. Conclusions: These data suggest that improved clinical outcomes with IVO+AZA are associated with sustained clearance of the m IDH1 clone including pts with disease that harbor mutations implicated in resistance to IVO monotherapy (e.g., with RTK pathway mutations). Clinical trial information: NCT03173248.

Impact of mutant IDH (mIDH) inhibition on DNA hydroxymethylation, tumor cell function, and tumor immune microenvironment (TIME) in resected mIDH1 lower-grade glioma (LGG)

2008

Background: Somatic mutations in IDH1 and IDH2 occur in ̃80% and ̃4% of LGGs, respectively, promoting tumorigenesis via increased levels of the oncometabolite D-2-hydroxyglutarate (2-HG). Vorasidenib (VOR; AG-881) is an oral, brain-penetrant, dual inhibitor of mIDH1/2; ivosidenib (IVO; AG-120) is a first-in-class oral inhibitor of mIDH1. In this ongoing perioperative study, treatment with IVO/VOR reduced 2-HG levels in resected tumors vs untreated control tumors in patients (pts) with LGG (NCT03343197; Mellinghoff SNO 2019). We assessed the biological impact of 2-HG suppression on tumors and TIME. Methods: Pts (n = 49) with recurrent, non-enhancing, mIDH1-R132H LGG eligible for resection were randomized to IVO (500 mg QD/250 mg BID), VOR (10/50 mg QD), or no treatment, for 4 weeks preoperatively. Tumor tissue samples collected at surgery were assessed in genomic (n = 42), transcriptomic (n = 42), and immunohistochemistry (IHC; n = 43) analyses. Unpaired t-test was used for statistical comparisons. Results: Optimal 2-HG suppression (post-treatment 2-HG below the upper limit of 2-HG levels in a reference set of 15 wild-type [wt] IDH samples) was observed in 23 of 40 pts, including 9 (90%) pts receiving VOR 50 mg QD and 6 (50%) receiving IVO 500 mg QD. Of samples with valid biomarker data, those with optimal 2-HG suppression (n = 21) showed upregulation of neural differentiation-related gene expression, but downregulation of stemness-related gene expression, vs those with suboptimal 2-HG suppression (post-treatment 2-HG above upper limit of wt IDH 2-HG levels; n = 17; p < 0.01). IHC analysis of the proliferation marker Ki-67 showed a ̃2-fold decrease in Ki-67–positive cells in samples with optimal 2-HG suppression (mean 2.7%; n = 22) vs those with suboptimal suppression (5.8%; n = 16; p < 0.05). Epigenetic analysis revealed a ̃2-fold increase in mean 5-hydroxymethylcytosine (5hmC) levels in samples with optimal (0.36%; n = 17) vs suboptimal 2-HG suppression (0.2%; n = 15; p < 0.05), suggesting reversal of TET2 inhibition. IHC analysis of TIME revealed increases in mean CD3+ and CD8+ tumor-infiltrating lymphocyte levels in samples with optimal (1.05% [CD3]/0.22% [CD8]; n = 22) vs suboptimal 2-HG suppression (0.44% [CD3]/0.07% [CD8]; n = 16; p < 0.05). Optimal 2-HG suppression was associated with upregulation of gene expression related to type I interferon signaling and antigen presentation (p < 0.01). Conclusions: These data suggest that both tumor-intrinsic and -extrinsic mechanisms underlie 2-HG suppression by VOR and IVO. VOR, and IVO to a lesser extent, increased 5hmC, promoted cellular differentiation, and inhibited tumor cell proliferation; both also increased T-cell infiltration, activated interferon signaling, and increased antigen presentation capability. These data support development of VOR in combination with immunotherapy. Clinical trial information: NCT03343197.

Final results from ClarIDHy, a global, phase 3, randomized, double-blind study of ivosidenib (IVO) versus placebo (PBO) in patients (pts) with previously treated cholangiocarcinoma (CCA) and an isocitrate dehydrogenase 1 (IDH1) mutation

4069

Background: CCA is a rare cancer for which there are limited effective therapies. IDH1 mutations occur in ̃20% of intrahepatic CCAs, resulting in production of the oncometabolite D-2-hydroxyglutarate, which promotes oncogenesis. IVO (AG-120) is a first-in-class, oral, small-molecule inhibitor of mutant IDH1 (mIDH1). ClarIDHy aimed to demonstrate the efficacy of IVO vs PBO in pts with unresectable or metastatic m IDH1 CCA. The primary endpoint was met with significant improvement in progression-free survival (PFS) by independent radiology center (IRC) with IVO vs PBO (hazard ratio [HR] = 0.37, p < 0.0001). Objective response rate (ORR) and stable disease for IVO were 2.4% (3 partial responses) and 50.8% (n = 63) vs 0% and 27.9% (n = 17) for PBO. IVO pts experienced significantly less decline in physical and emotional functioning domains of quality of life at cycle 2 day 1 vs PBO pts (nominal p < 0.05). Methods: Pts with m IDH1 CCA were randomized 2:1 to IVO (500 mg PO QD) or matched PBO and stratified by prior systemic therapies (1 or 2). Key eligibility: unresectable or metastatic m IDH1 CCA based on central testing; ECOG PS 0–1; measurable disease (RECIST v1.1). Crossover from PBO to IVO was permitted at radiographic progression. Primary endpoint: PFS by IRC. Secondary endpoints included overall survival (OS; by intent-to-treat), ORR, PFS (by investigator), safety, and quality of life. The planned crossover-adjusted OS was derived using the rank-preserving structural failure time (RPSFT) model. Results: As of 31 May 2020, ̃780 pts were prescreened for an IDH1 mutation and 187 were randomized to IVO (n = 126) or PBO (n = 61); 13 remain on IVO. Median age 62 y; M/F 68/119; 91% intrahepatic CCA; 93% metastatic disease; 47% had 2 prior therapies. 70% of PBO pts crossed over to IVO. OS data were mature, with 79% OS events in IVO arm and 82% in PBO. Median OS (mOS) was 10.3 months for IVO and 7.5 months for PBO (HR = 0.79; 95% CI 0.56–1.12; one-sided p = 0.093). The RPSFT-adjusted mOS was 5.1 months for PBO (HR = 0.49; 95% CI 0.34–0.70; p < 0.0001). Common all-grade treatment emergent adverse events (TEAEs, ≥ 15%) in the IVO arm: nausea 41%, diarrhea 35%, fatigue 31%, cough 25%, abdominal pain 24%, decreased appetite 24%, ascites 23%, vomiting 23%, anemia 18%, and constipation 15%. Grade ≥ 3 TEAEs were reported in 50% of IVO pts vs 37% of PBO pts, with grade ≥ 3 treatment-related AEs in 7% of IVO pts vs 0% in PBO. 7% of IVO pts experienced an AE leading to treatment discontinuation vs 9% of PBO pts. There were no treatment-related deaths. Conclusions: IVO was well tolerated and resulted in a favorable OS trend vs PBO despite a high rate of crossover. These data – coupled with statistical improvement in PFS, supportive quality of life data, and favorable safety profile – demonstrate the clinical benefit of IVO in advanced m IDH1 CCA. Clinical trial information: NCT02989857.

Final results from ClarIDHy, a global, phase III, randomized, double-blind study of ivosidenib (IVO) versus placebo (PBO) in patients (pts) with previously treated cholangiocarcinoma (CCA) and an isocitrate dehydrogenase 1 (IDH1) mutation

266

Background: CCA is a rare cancer for which there are limited effective therapies. IDH1 mutations occur in ~20% of intrahepatic CCAs, resulting in production of the oncometabolite D-2-hydroxyglutarate, which promotes oncogenesis. IVO (AG-120) is a first-in-class, oral, small-molecule inhibitor of mutant IDH1 (m IDH1). ClarIDHy aimed to demonstrate the efficacy of IVO vs PBO in pts with unresectable or metastatic m IDH1 CCA. The primary endpoint was met with significant improvement in progression-free survival (PFS) by independent radiology center (IRC) with IVO vs PBO (hazard ratio [HR] = 0.37, p < 0.0001). Objective response rate (ORR) and stable disease for IVO were 2.4% (3 partial responses) and 50.8% (n = 63) vs 0% and 27.9% (n = 17) for PBO. IVO pts experienced significantly less decline in physical and emotional functioning domains of quality of life at cycle 2 day 1 vs PBO pts (nominal p < 0.05). Methods: Pts with m IDH1 CCA were randomized 2:1 to IVO (500 mg PO QD) or matched PBO and stratified by prior systemic therapies (1 or 2). Key eligibility: unresectable or metastatic m IDH1 CCA based on central testing; ECOG PS 0–1; measurable disease (RECIST v1.1). Crossover from PBO to IVO was permitted at radiographic progression. Primary endpoint: PFS by IRC. Secondary endpoints included overall survival (OS; by intent-to-treat), ORR, PFS (by investigator), safety, and quality of life. The planned crossover-adjusted OS was derived using the rank-preserving structural failure time (RPSFT) model. Results: As of 31 May 2020, ~780 pts were prescreened for an IDH1 mutation and 187 were randomized to IVO (n = 126) or PBO (n = 61); 13 remain on IVO. Median age 62 y; M/F 68/119; 91% intrahepatic CCA; 93% metastatic disease; 47% had 2 prior therapies. 70% of PBO pts crossed over to IVO. OS data were mature, with 79% OS events in IVO arm and 82% in PBO. Median OS (mOS) was 10.3 months for IVO and 7.5 months for PBO (HR = 0.79; 95% CI 0.56–1.12; one-sided p = 0.093). The RPSFT-adjusted mOS was 5.1 months for PBO (HR = 0.49; 95% CI 0.34–0.70; p < 0.0001). Common all-grade treatment emergent adverse events (TEAEs, ≥ 15%) in the IVO arm: nausea 41%, diarrhea 35%, fatigue 31%, cough 25%, abdominal pain 24%, decreased appetite 24%, ascites 23%, vomiting 23%, anemia 18%, and constipation 15%. Grade ≥ 3 TEAEs were reported in 50% of IVO pts vs 37% of PBO pts, with grade ≥ 3 treatment-related AEs in 7% of IVO pts vs 0% in PBO. 7% of IVO pts experienced an AE leading to treatment discontinuation vs 9% of PBO pts. There were no treatment-related deaths. Conclusions: IVO was well tolerated and resulted in a favorable OS trend vs PBO despite a high rate of crossover. These data – coupled with statistical improvement in PFS, supportive quality of life data, and favorable safety profile – demonstrate the clinical benefit of IVO in advanced m IDH1 CCA. Clinical trial information: NCT02989857.

INDIGO: A global, randomized, double-blind, phase III study of vorasidenib (VOR; AG-881) vs placebo in patients (pts) with residual or recurrent grade II glioma with an isocitrate dehydrogenase 1/2 (IDH1/2) mutation

TPS2574

Background: Low-grade gliomas (LGGs; WHO grade II) are incurable and ultimately progress to high-grade gliomas. The current treatment options consist of surgery followed by observation (“watch and wait”) for pts with lower risk for disease progression or post-operative chemo-radiotherapy (high-risk population). There are no approved targeted therapies. IDH1 and IDH2 mutations (m IDH1/2) occur in approximately 70% and 4% of LGGs, respectively, and promote tumorigenesis via neomorphic production of D-2-hydroxyglutarate (2-HG). VOR, an oral, potent, reversible, brain-penetrant inhibitor of mIDH1/2, was evaluated in 76 pts with glioma in two phase 1 studies (dose escalation and perioperative) and was associated with a favorable safety profile at doses of < 100 mg daily. Preliminary clinical activity was observed in non-enhancing glioma pts in both studies, most recently with an objective response rate (ORR) of 30.8% at 50 mg QD in the perioperative study and > 90% 2-HG suppression at this dose level relative to untreated control samples (Mellinghoff et al., J Clin Oncol 2019). Methods: Approximately 366 pts will be randomized 1:1 to VOR (50 mg QD) or matched placebo and stratified by 1p19q status (intact vs co-deleted). Key eligibility criteria include: age ≥12 years; grade 2 oligodendroglioma or astrocytoma (per WHO 2016 criteria) not in need of immediate treatment and without high-risk features; centrally confirmed m IDH1/2 status; ≥1 prior surgery for glioma within the previous 5 years but no other anticancer therapy; Karnofsky performance status ≥80%; and centrally confirmed measurable, non-enhancing disease evaluable by magnetic resonance imaging. Crossover from placebo to the VOR arm is permitted upon centrally confirmed radiographic progression per RANO-LGG criteria. Primary endpoint is progression-free survival assessed by independent review. Secondary endpoints include safety and tolerability, tumor growth rate assessed by volume, time to next intervention, ORR, overall survival, quality of life assessed by the Functional Assessment of Cancer Therapy–Brain questionnaire, and plasma pharmacokinetics. Exploratory endpoints include seizure activity and neuro-cognitive function. Clinical data will be reviewed regularly throughout the study by an independent data monitoring committee. The study is currently enrolling pts in the US, with additional countries planned (NCT04164901). Clinical trial information: NCT04164901 .

Vorasidenib (VOR; AG-881), an inhibitor of mutant IDH1 and IDH2, in patients (pts) with recurrent/progressive glioma: Updated results from the phase I non-enhancing glioma population

2504

Background: Isocitrate dehydrogenase 1 and 2 mutations (m IDH1/2) occur in approximately 70% and 4% of low-grade gliomas (LGGs), respectively, promoting oncogenesis via increased production of D-2-hydroxyglutarate. In this ongoing phase 1 trial, VOR, a potent, oral, reversible, brain-penetrant, first-in-class dual inhibitor of mIDH1/2, is being evaluated in advanced m IDH1/2 solid tumors, including gliomas. Safety and preliminary results were presented previously (Mellinghoff et al., J Clin Oncol 2018). Here, we report updated data for the non-enhancing glioma pt population. Methods: Pts with recurrent/progressive m IDH1/2 glioma received VOR daily (continuous 28-day cycles). Key eligibility criteria included: ≥18 years; histologically or cytologically confirmed glioma with documented m IDH1/2; ECOG 0-2; and evaluable disease by RANO-LGG criteria. Dose escalation cohorts enrolled using a Bayesian logistic regression model (BLRM) escalation guided by the overdose control (EWOC). Tumor response was evaluated by MRI every 8 weeks using RANO-LGG criteria by local assessment. Results: As of 28 Nov 2019, 22 pts with non-enhancing glioma had received VOR and 8 (36%) remain on treatment. M/F, 8/14; grade 2/3, 17/5; median age, 47 years; m IDH1/2, 20/1; 1p19q intact, 9/22; median (range) number of prior systemic therapies, 2 (1–4). Common (≥5 pts) treatment-emergent adverse events (AEs) of any grade and regardless of causality included increased ALT/AST (63.6%/59.1%), headache (45.5%), nausea (40.9%), neutropenia (31.8%), fatigue and hyperglycemia (27.3% each), and seizures and decreased white blood cell count (22.7% each). Transaminase elevations were grade 1 in severity at dose levels < 100mg and were less frequent (5 [38.5%] of 13 pts). Three subjects had related grade ≥3 AEs; 2 discontinued due to AEs. Objective response rate was 13.6% (1 partial response, 2 minor responses), and 17 (77.3%) pts achieved stable disease. 60.5% of pts were progression free and alive at 24 months. Conclusions: In this previously treated population with non-enhancing glioma, VOR was associated with a favorable safety profile. The study results also show encouraging preliminary activity within that population, with PFS duration extending to 24 months or longer in 60% of participants. A global randomized phase 3 study of VOR in grade 2 non-enhancing glioma pts who have had surgery only is currently enrolling (NCT04164901). Clinical trial information: NCT02481154 .

IDH1 mutation detection in plasma circulating tumor DNA (ctDNA) and association with clinical response in patients with advanced intrahepatic cholangiocarcinoma (IHC) from the phase III ClarIDHy study

4576

Background: Mutations in isocitrate dehydrogenase 1 ( IDH1) are detected in ~13% of IHCs. Ivosidenib (IVO) is a first-in-class, oral inhibitor of the mutant IDH1 (mIDH1) protein. In ClarIDHy, a global, phase 3, double-blind study in previously treated patients with advanced m IDH1 IHC (N = 186), IVO demonstrated an improvement in progression-free survival (PFS) vs placebo (hazard ratio 0.37, p < 0.001) (Abou-Alfa et al., Ann Oncol 2019; NCT02989857). Feasibility of m IDH1 detection in plasma ctDNA from patients with IHC was demonstrated and was highly concordant with mutation status in tumor tissue (Aguado-Fraile et al., Cancer Res 2019). This analysis was extended to the larger patient cohort from ClarIDHy, and longitudinal m IDH1 detection from ctDNA was assessed and correlated with clinical response. Methods: Baseline plasma and tumor tissue samples were obtained before randomization; longitudinal plasma samples were collected on day 1 of each treatment cycle. m IDH1 status in tissue was prospectively and centrally confirmed using Oncomine Focus Assay. A BEAMing digital PCR test was used for quantification of m IDH1 in plasma. IDH1 mutation clearance ( IDH1-MC) was achieved when plasma m IDH1 variant allele frequency was below the assay’s sensitivity (0.02% for R132C/L/S/G; 0.04% for R132H). Results: m IDH1 detection in plasma ctDNA and tissue was concordant in 92% (193/210) of samples screened. As of 31 Jan 2019, median PFS was 2.7 months for IVO vs 1.4 months for placebo. Longitudinal analysis with biomarker data available as of Jan 2020 demonstrated IDH1-MC in plasma from 10 IVO-treated patients with PFS ≥2.7 months (n = 36) vs 0 patients with PFS < 2.7 months (n = 40). No IDH1-MC was observed in patients treated with placebo, irrespective of response (n = 49). Conclusions: These results reinforce the feasibility of IDH1-R132 detection in plasma from patients with IHC, with a 92% concordance with detection in tumor tissue, supporting m IDH1 detection in liquid biopsy as a viable patient selection strategy where tissue exhaustion can limit conventional methods. Plasma IDH1-MC was also observed in a subset of IVO-treated patients who achieved disease control. Clinical trial information: NCT02989857 .

Pharmacokinetics/pharmacodynamics (PK/PD) of ivosidenib in patients with mutant IDH1 advanced cholangiocarcinoma from the phase III ClarIDHy study

539

Background: Mutations in isocitrate dehydrogenase 1 (m IDH1) occur in up to 20% of intrahepatic cholangiocarcinomas (CC), leading to accumulation of 2-hydroxyglutarate (2-HG) and epigenetic dysregulation, promoting oncogenesis. Ivosidenib (IVO; AG-120), a first in-class, oral, targeted inhibitor of the mIDH1 enzyme, showed improved progression-free survival and a positive trend in overall survival versus placebo (PBO) in ClarIDHy, a global, phase 3, multicenter, double-blind study (Abou-Alfa et al. ESMO 2019 LBA10_PR; NCT02989857). Methods: Patients (pts) with unresectable or metastatic m IDH1 CC were randomized 2:1 to IVO (500 mg once daily in continuous 28-day cycles) or matched PBO, stratified by number of prior systemic therapies (1 or 2). Crossover from PBO to IVO was permitted at radiographic progressive disease. Blood samples for PK/PD analyses, a secondary endpoint, were collected predose, 0.5, 2, and 4 h postdose on day (D) 1 of cycles (C) 1–2, predose and 2 h postdose on D15 of C1–2, and predose on D1 from C3 onwards. Plasma IVO and 2-HG were measured using validated or qualified LC-MS/MS methods. Results: As of 31Jan2019, 185 pts were randomized to IVO (n = 124) or PBO (n = 61); 35 pts crossed over to IVO. PK/PD analysis was available from 156 pts receiving IVO. IVO was absorbed rapidly following single and multiple oral doses; exposure, as measured by Cmax and AUC, was higher at C2D1 than after a single dose, with low accumulation. Plasma IVO reached steady state within C1 of daily dosing. In pts receiving IVO, baseline mean plasma 2-HG concentration was reduced from 1108 ng/mL to 97.7 ng/mL at C2D1, close to levels in healthy subjects (72.6±21.8 ng/mL). 2-HG inhibition was robust and persistent up to Cycle 19. An average 2-HG inhibition of 75.0% (up to 97.3%) was observed at steady-state after multiple IVO administrations. No plasma 2-HG decreases were seen with PBO. Analyses of plasma 2-HG levels and association with clinical outcomes will be presented. Conclusions: In pts with advanced m IDH1 CC, oral IVO 500 mg once-daily demonstrated good exposure, and maintained the inhibition of 2-HG to levels observed in healthy subjects, whereas 2-HG remained elevated with PBO. Clinical trial information: NCT02989857.

A phase I, open label, perioperative study of AG-120 and AG-881 in recurrent IDH1 mutant, low-grade glioma: Results from cohort 1

2003

Background: AG-120 (ivosidenib [IVO]) is a first-in-class oral inhibitor of mutant isocitrate dehydrogenase 1 (mIDH1) evaluated in 66 glioma patients (pts) in an ongoing phase 1 study. AG-881 (vorasidenib [VOR]) is an oral, potent, brain-penetrant inhibitor of mIDH1/2 evaluated in 52 glioma pts in an ongoing phase 1 study. In an orthotopic glioma model, IVO and VOR reduced 2-hydroxyglutarate (2-HG) by 85% and 98%, respectively, despite different brain:plasma ratios (<0.04 vs 1.33). Methods: Primary endpoint: brain tumor 2-HG concentration with IVO or VOR treatment in mIDH1 low-grade glioma. Pts with recurrent non-enhancing WHO-2016 Grade (Gr) 2 or 3 mIDH1-R132H oligodendroglioma or astrocytoma undergoing craniotomy were randomized 2:2:1 to IVO 500mg QD, VOR 50mg QD, or no treatment for 4 wks preoperatively in Cohort 1. Post-operatively, pts continued to receive IVO or VOR and control pts were randomized 1:1 to IVO or VOR. Tumors were assessed for mIDH1 status, cellularity, 2-HG, and drug concentration. Treated samples were compared to control pts and mIDH1 and wild type (WT) banked reference (ref) samples. Plasma and CSF 2-HG were assessed. Pts with non-evaluable tissue were replaced. Results: As of 29 Nov 2018, 26 pts (17M, 9F; 25 Gr 2, 1 Gr 3) were randomized preoperatively (IVO 10, VOR 11, control 5), 25 received drug (IVO 12, VOR 13). At the data cut, 19 tumors were analyzed with 16 evaluable. Common (>10%) TEAEs (all grade 1/2): diarrhea (36%), hypocalcemia and constipation (each 20%), anemia, hyperglycemia, pruritus, headache and nausea (each 16%), and hypokalemia and fatigue (each 12%). Mean brain:plasma ratio: 0.16 for IVO, 2.4 for VOR. Tumor 2-HG results are shown in Table. Updated data from Cohort 1 will be presented. Conclusions: In Cohort 1 of this phase 1 perioperative study, IVO and VOR were CNS penetrant and lowered 2-HG compared to untreated samples. Cohort 2 is open and will evaluate IVO 250mg BID and VOR 10mg QD. Brain tumor 2-HG concentration. Clinical trial information: NCT03343197. [Table: see text]

ClarIDHy: A phase 3 multicenter randomized double-blind study of AG-120 versus placebo in patients with non-resectable or metastatic cholangiocarcinoma with an IDH1 mutation

TPS545

Background: Advanced cholangiocarcinoma (CC) is a life-threatening disease with limited effective chemotherapy options. Mutations in isocitrate dehydrogenase 1 (mIDH1) occur in 13–15% of CC cases, and up to 25% of intrahepatic CC cases, leading to epigenetic and genetic changes that promote oncogenesis via production of the oncometabolite 2-hydroxyglutarate (2-HG). AG-120 (ivosidenib), a first-in-class oral mIDH1 inhibitor, displayed a favorable safety profile and clinical activity in a phase 1 study enrolling 73 mIDH1 CC patients who had received ≥1 prior systemic regimen. As of 10 Mar 2017, 4/73 (5%) had a partial response and 41/73 (56%) stable disease. Progression free survival (PFS) rates at 6 months and 12 months were 38.5% and 20.7%, respectively. The 500 mg once daily dose level of AG-120 was selected for further development in mIDH1 CC. Methods: ClarIDHy is a global, phase 3, multicenter, double-blind, randomized (2:1) study of AG-120 (500 mg once daily) vs. matched placebo in 186 mIDH1 CC patients (ClinicalTrials.gov NCT02989857). Key eligibility criteria: non-resectable or metastatic CC, documented mIDH1 by central laboratory testing, ECOG performance status 0–1, measurable disease (RECIST v1.1), documented disease progression after ≤2 prior systemic therapies in the advanced setting including at least 1 gemcitabine- or 5-fluorouracil-containing regimen, and no prior mIDH inhibitor therapy. Crossover from placebo to AG-120 will be allowed at time of radiographic disease progression. Primary endpoint: PFS assessed by independent radiologists. Secondary endpoints: safety, tolerability, overall response rate (RECIST 1.1), overall survival, pharmacokinetic/pharmacodynamic analyses, and quality of life (EORTC QLQ-C30 and QLQ-BIL21 scales). An independent data monitoring committee will monitor the data during study conduct. The ClarIDHy study is currently activated at participating sites in the US, UK, EU, and S. Korea. R eused with permission from the American Society of Clinical Oncology (ASCO). This abstract was accepted and previously presented at the 2017 ASCO Annual Meeting. All rights reserved. Clinical trial information: NCT02989857.

ClarIDHy: A phase 3, multicenter, randomized, double-blind study of AG-120 vs placebo in patients with an advanced cholangiocarcinoma with an IDH1 mutation

TPS4142

Background: Advanced cholangiocarcinoma (CC) is a life-threatening disease for which there are limited therapeutic options. Mutations in isocitrate dehydrogenase 1 (mIDH1) occur in up to 25% of intrahepatic CC cases. mIDH1 lead to epigenetic and genetic changes that promote oncogenesis via production of the oncometabolite, D-2-hydroxyglutarate (2-HG). AG-120 is a first-in-class oral inhibitor of the mIDH1 enzyme, and is being tested in a phase 1 study that enrolled 73 patients (pts) with mIDH1 CC who had received a median of 2 prior therapies (range 1–5). AG-120 has demonstrated a favorable safety profile and clinical activity in this study. Among the 72 efficacy evaluable pts (≥1 post-baseline response assessment or discontinued prematurely), 6% (n = 4) had a confirmed partial response and 56% (n = 40) had stable disease. Progression-free survival (PFS) rate at 6 months was 40% as of Dec 16, 2016. The 500 mg once daily (QD) dose of AG-120 was selected for the ongoing phase 3 study in mIDH1 CC described here. Methods: ClarIDHy is a global, phase 3, multicenter, double-blind study randomizing 186 pts with mIDH1 CC in a 2:1 ratio to AG-120 (500 mg QD) or matched placebo (NCT02989857). Key eligibility criteria: nonresectable or metastatic CC; documented mIDH1 based on central laboratory testing; ECOG 0–1; measurable disease (RECIST v1.1); documented disease progression following ≤2 prior systemic therapies in the advanced setting, including at least 1 gemcitabine- or 5-fluorouracil-containing regimen; and no prior mIDH inhibitor therapy. Crossover from the placebo arm to the AG-120 arm will be permitted. The primary endpoint is PFS as assessed by an independent review. Secondary endpoints include safety, tolerability, overall response rate, overall survival, pharmacokinetic and pharmacodynamic analyses on plasma, and quality of life as assessed by the EORTC QLQ-C30, EORTC QLQ-BIL21, and EQ-5D-5L instruments. An independent data monitoring committee will monitor the data throughout the study. The ClarIDHy study is currently activated at participating sites in the US and will be activated in centers throughout Europe and in South Korea. Clinical trial information: NCT02989857.

Phase I study of AG-120, an IDH1 mutant enzyme inhibitor: Results from the cholangiocarcinoma dose escalation and expansion cohorts

4015

Background: Mutations in the metabolic enzyme isocitrate dehydrogenase 1 (mIDH1) occur in patients (pts) with cholangiocarcinoma (CC) and are detected in up to 25% of intrahepatic CC. mIDH1 produce the oncometabolite, D-2-hydroxyglutarate (2-HG), resulting in epigenetic and genetic dysregulation and oncogenesis. AG-120 is a first-in-class, potent, oral inhibitor of mIDH1 tested in this phase I study in mIDH1 solid tumors, including CC. Methods: AG-120 was escalated in a 3+3 design from 100 mg twice daily to 1200 mg once daily (QD) in 28-day cycles (N = 60, mIDH1 advanced solid tumors). Key eligibility for CC: recurrence of progressive mIDH1 CC following standard therapy (dose escalation) or at least a prior gemcitabine-based regimen (expansion cohort). Response (RECIST 1.1) was assessed every 8 weeks. Plasma and tumor tissue were collected for exploratory analyses. Results: Based on the safety, pharmacokinetic, and pharmacodynamic data from dose escalation, the 500 mg QD dose was selected for expansion in mIDH1 CC and other mIDH1 solid tumors. As of Dec 16, 2016, 73 pts with mIDH1 CC had been dosed in the dose escalation (n = 24) and expansion (n = 49) cohorts. Demographics: M/F = 24/49, median number of prior therapies = 2 (range 1–5), ECOG 0–1 = 26/47. There were no dose-limiting toxicities. Treatment-related adverse events (AEs) in ≥5% pts: fatigue (21%), nausea (18%), vomiting (12%), diarrhea (10%), decreased appetite (8%), dysgeusia (5%), QT prolongation (5%). Two (3%) pts experienced related grade 3 AEs: fatigue and low phosphorus. There were no AG-120-related AEs leading to discontinuation. Among the 72 efficacy evaluable (≥1 post baseline response assessment or discontinued prematurely) mIDH1 CC pts (24 in escalation and 48 in expansion cohort), 6% (n = 4) had a confirmed partial response and 56% (n = 40) experienced stable disease. The progression-free survival rate at 6 months was 40%, and 8 pts have been treated with AG-120 for ≥1 year. Conclusions: In this pretreated mIDH1 CC population, AG-120 was associated with a favorable safety profile and prolonged stable disease. A global, phase III, randomized, placebo-controlled study of AG-120 in mIDH1 CC has been initiated (ClarIDHy). Clinical trial information: NCT02073994.

Pharmacokinetic/pharmacodynamic (PK/PD) profile of AG-120 in patients with IDH1-mutant cholangiocarcinoma from a phase 1 study of advanced solid tumors

4082

Background: Somatic mutations in isocitrate dehydrogenase 1 (IDH1) produce the oncometabolite D-2-hydroxyglutarate (2-HG). AG-120 is a first-in-class selective inhibitor of mutant IDH1 (mIDH1) under evaluation in an ongoing phase 1 study in patients with mIDH1 advanced solid tumors, including cholangiocarcinoma (CC) (NCT02073994). Objectives for this abstract were to 1) characterize the PK profile of AG-120 and the relationship between AG-120 exposure and 2-HG suppression, and 2) evaluate the influence of intrinsic patient factors on AG-120 clearance, in patients with mIDH1 CC. Methods: AG-120 was administered orally once daily (QD) or twice daily (BID) in continuous 28-day cycles. As of Dec 5, 2016, 60 of 73 patients enrolled with mIDH1 CC had PK/PD samples available for analysis at 100 mg BID, 300 mg QD, 400 mg QD, 500 mg QD, 800 mg QD, and 1200 mg QD in dose escalation (n = 24) and 500 mg QD (n = 36) in dose expansion. Blood (n = 60) and fresh tumor biopsy samples (n = 14) were collected to assess AG-120 and 2-HG using qualified liquid chromatography-tandem mass spectrometry methods. Results: Following both single and multiple doses, AG-120 plasma exposure increased less than dose proportionally from 100 to 1200 mg. Mean terminal half-life was 38.4–85.8 h, supporting a QD dosing regimen. Following multiple doses, steady state was reached within 15 days, with approximately 2-fold accumulation in plasma AG-120 exposure. No patient-specific factors were identified as clinically significant covariates affecting AG-120 plasma clearance. After multiple doses, plasma 2-HG levels were reduced (up to 98.4% inhibition, achieving levels similar to those in healthy volunteers) and tumor biopsy 2-HG levels were also substantially reduced (by up to 99.9%) at all dose levels tested. The 500 mg QD dose resulted in the largest magnitude of 2-HG inhibition vs. other dose levels. Conclusions: AG-120 demonstrated a long half-life in patients with mIDH1 CC and robustly inhibited 2-HG in plasma and tumor samples. These PK/PD data, along with emerging safety and clinical activity data, support the selection of 500 mg QD for future clinical investigation. Clinical trial information: NCT02073994.

DART Study: A phase II randomized trial of dalantercept plus axitinib versus placebo plus axitinib in advanced clear cell renal cell carcinoma (RCC): Results from Part 1

407

Background: Activin receptor-like kinase 1 (ALK1) is a novel target in angiogenesis involved in blood vessel maturation and stabilization. Concurrent targeting of ALK1 and vascular endothelial growth factor (VEGF) signaling results in dual angiogenic blockade and augmented inhibition of tumor growth in RCC xenograft models. Dalantercept (Dal) is an ALK1 receptor-fusion protein that acts as a ligand trap and has demonstrated monotherapy activity with an acceptable safety profile in a completed phase I study. Methods: Part 1 of this study evaluated the safety, tolerability, and preliminary activity of escalating dose levels of Dal plus fixed dose axitinib in pts with advanced RCC. 3-6 pts each received Dal (0.6, 0.9, or 1.2 mg/kg) SC Q3W and axitinib 5 mg PO BID. Key eligibility: predominantly clear cell RCC, 1 prior VEGFR TKI, ≤3 prior tx. Results: As of September 12, 2014, 29 pts were enrolled in three cohorts (n=6, 9, 14) at dose levels of 0.6, 0.9 and 1.2 mg/kg, respectively. At the 1.2 mg/kg dose level, 1 DLT of grade 3 abdominal and back pain occurred (n=1) in addition to more Dal associated edema events including peripheral edema (n=6), fluid overload (n=1), ascites (n=1), and pleural effusion (n=1). The 0.9 mg/kg dose level was well tolerated (3 pts with low grade edema; no pleural effusions or ascites) and selected for Part 2. Frequent AEs regardless of attribution: fatigue, diarrhea, dysphonia, nausea, peripheral edema, creatinine rise, epistaxis, hypertension, arthralgia, hand-foot rash, and cough. 28 pts were evaluable for response by RECIST 1.1. The ORR was 25% (n=7) and 31.3% (n=5) among pts who received ≥ 2 prior txs (n=16), including VEGF targeted tx, mTOR inhibitors, and immune tx. Of those evaluable for disease control at 6 mos. (n=25, 3 active pts have not reached 6 mos.), 52% (n=13) remained progression free. PFS data are maturing and will be presented. Conclusions: The combination of dalantercept and axitinib is well tolerated and associated with encouraging activity in pts with prior VEGF, mTOR, and immune therapies. Part 2 of this study randomizes pts to dalantercept + axitinib vs. placebo + axitinib and is actively accruing patients. Clinical trial information: NCT01727336.

The DASH Study: A phase 1b study of dalantercept plus sorafenib in advanced hepatocellular carcinoma

TPS495

Background: The activin receptor-like kinase (ALK1) pathway is a novel target in angiogenesis that promotes blood vessel maturation and stabilization. ALK1 binds to the ligand bone morphogenetic protein 9 (BMP9) which is overexpressed in hepatocellular carcinoma (HCC) compared to normal hepatocytes. Dalantercept is an ALK1 receptor fusion protein that binds BMP9 and acts as a ligand trap. Sorafenib, a multi-kinase and vascular endothelial growth factor receptor tyrosine kinase inhibitor (VEGFR TKI), is the standard therapy for advanced HCC. In a preclinical model of HCC, simultaneous blockade of ALK1 and VEGF signaling with dalantercept and sorafenib resulted in additive tumor growth inhibition. In a completed Phase 1 study in thirty-seven subjects with solid tumors, dalantercept monotherapy demonstrated preliminary anti-tumor activity and a safety profile that was generally non-overlapping with VEGFR TKIs. Methods: An open label, multi-center, dose escalating, phase 1b study to evaluate dalantercept plus sorafenib in subjects with advanced HCC is ongoing. The primary endpoint includes the evaluation of the safety and tolerability of dalantercept plus sorafenib and determination of the recommended phase 2 dose levels of the combination. Secondary endpoints include assessments of the pharmacokinetic profile of the combination, preliminary activity including response rate using RECIST 1.1 and time to progression, and pharmacodynamic biomarkers in the serum and tissue including ALK1 and BMP9 expression. In the first two cohorts of 3-6 subjects each, the dalantercept dose levels will be 0.6 and 0.9 mg/kg, respectively, administered subcutaneously (SC) every 3 weeks in combination with sorafenib 400 mg PO once daily. In cohort three, 3-6 subjects will receive dalantercept dose level 0.9 mg/kg SC every 3 weeks with sorafenib 400 mg PO twice daily. Patient safety data through day 22 will be evaluated prior to escalation to the next cohort. An expansion cohort will enroll 10-20 subjects at or below the maximum tolerated dose level. Key eligibility criteria: histologically confirmed advanced HCC, Child-Pugh A liver disease, ECOG performance status of 0-1, and no prior systemic therapy in the advanced setting. Clinical trial information: NCT02024087.

Phase II study of dalantercept, a novel inhibitor of ALK1-mediated angiogenesis, in patients with recurrent or metastatic squamous cell carcinoma of the head and neck

TPS6098

Background: Despite advances in the treatment of recurrent or metastatic squamous cell carcinoma of the head and neck (SCCHN), the prognosis remains poor with a need to develop novel therapeutic strategies. Targeting angiogenesis in SCCHN is an active area of clinical research. Activin receptor-like kinase 1 (ALK1) is a type 1 receptor in the TGF-ß superfamily which is selectively expressed on activated endothelial cells. ALK1 binds bone morphogenetic proteins (BMP) 9 and 10 (ligands for ALK1) and is primarily involved in the maturation stage of angiogenesis. Dalantercept is a human ALK1-Fc receptor fusion protein that binds BMP9/10 and acts as a ligand trap. In preclinical tumor models, dalantercept demonstrated a decrease in tumor vascularization and delayed tumor growth. In a completed phase I study, dalantercept demonstrated anti-tumor activity in patients with advanced solid tumors including SCCHN. Methods: An open label, multi-center, multiple dose, phase II study to evaluate dalantercept in patients with advanced SCCHN is ongoing. Dalantercept is being administered every three weeks via SC injection in a total of 45 patients to assess safety, tolerability, and efficacy. 13 patients were enrolled at the 0.6 mg/kg dose level. To date, 6 out of 30 planned patients have received dalantercept at the 1.2 mg/kg dose level. Key inclusion criteria are tumors arising from the oral cavity, oropharynx, hypopharynx, or larynx, at least one prior platinum-containing regimen, ECOG performance status </= 1, and measurable disease. Exclusion criteria include prior anti-angiogenesis therapy, significant pulmonary, cardiovascular, or bleeding risk. The primary efficacy endpoint is RR. Secondary endpoints include PFS, OS, TTP, DOR, DCR, and PD biomarkers on tumor and serum specimens including BMP9/10 and ALK1 expression. Clinical trial information: NCT01458392.

Randomized, open-label, phase II trial of gemcitabine with or without bavituximab in patients with nonresectable stage IV pancreatic adenocarcinoma

4054

Background: Despite advances in the treatment of metastatic pancreatic cancer (PC), there is critical need to develop novel therapies.Median survival with combination chemotherapy is limited to less than one year and only the optimally conditioned patients can tolerate these therapies. Bavituximab (B) is a monoclonal antibody (mAB) directed againstphosphatidylserine (PS) that causes vascular shutdown and reactivation of the innate and adaptive immunity in animal models. Preclinical data in mouse PC models indicate that gemcitabine (G) increases PS exposure and the addition of a mAb targeting PS reduces tumor burden, visible liver metastases, microvessel density, and increases tumor macrophage infiltration compared to G alone (Beck et al. 2006). The purpose of this trial is to evaluate and compare the efficacy and safety of the combination of G+B vs. G alone as first line therapy in pts. with nonresectable Stage IV PC. Methods: Seventy patients were randomized (1:1) to receive G 1000 mg/m2 on days 1, 8, and 15 every 28Edays with or without weekly B 3mg/kg IV until disease progression or unacceptable toxicities. Key eligibility criteria were Stage IV PC, ECOG ≤2, measurable disease, age≥18 years, total bilirubin ≤1.5xULN, and adequate renal, hematologic, and hepatic function. The primary efficacy endpoint was overall survival (OS) and secondary endpoints included overall response rate (ORR) and progression free survival (PFS). Results: Of the 70 (G/G+B 34/36) patients randomized, 67 (G/G+B 33/34) received study treatment and 63 (G/G+B 31/32) were evaluable. No significant difference was seen in age, gender, race or ECOG. At analysis 87% deaths had been reported in G and 72% in G+B group. Median OS estimate is 5.2 months for G and 5.6 months for G+B. No difference between groups was observed in PFS (median 3.9 months for G and 3.7 months for G+B). ORR was 13% for G and 28% for G+B. Most AEs were grade 1-2 and typical of exposure to G. Conclusions: In this patient population with extensive disease burdens and limited treatment options, G+B was well tolerated and demonstrated moderate activity in tumor response and survival. Clinical trial information: NCT01272791.

Phase II randomized study of dalantercept in combination with axitinib compared to axitinib alone as second-line treatment in patients with metastatic renal cell carcinoma

TPS4595

Background: The treatment of metastatic renal cell cancer (mRCC) with therapies targeting the vascular endothelial growth factor (VEGF) pathway delays disease progression; however, overcoming tumor resistance to these agents remains a therapeutic challenge. Activin receptor-like kinase 1(ALK1) is a type 1 receptor in the TGF-ß superfamily and is selectively expressed on activated endothelial cells. While VEGF drives the proliferative stage of angiogenesis, ALK1 is primarily involved in the maturation phase. Dalantercept is a human ALK1-Fc receptor fusion protein that binds to bone morphogenetic proteins (BMP) 9 and 10 (ligands for ALK1) and acts as a ligand trap. Preclinically, dalantercept showed delayed tumor growth in solid tumor models, including RCC models alone and in combination with sunitinib. In RCC models, the addition of dalantercept to sunitinib enhanced the reduction in tumor blood flow compared to sunitinib alone. Dalantercept showed anti-tumor activity in a completed phase 1 study in 37 pts. with advanced solid tumors. Based on this promising data, we hypothesize that ALK1 inhibition may be synergistic with axitinib, a VEGFR tyrosine kinase inhibitor (TKI), in pts. with mRCC. Methods: A two-part, multi-center, open label phase 2 study to evaluate safety, tolerability, efficacy, pharmacokinetics (PK), and pharmacodynamics (PD) of dalantercept plus axitinib as second line therapy is ongoing. In Part 1, dose escalation using a 3+3 design will assess the safety and PK of dalantercept SC every 3 weeks plus axitinib 5 mg PO BID until disease progression or unacceptable toxicity. Once the maximum tolerated dose (MTD) has been determined, up to 20 pts. may be enrolled in an expansion cohort to establish safety for the recommended dose for Part 2. Part 2 will include 112 pts. randomized 1:1 to dalantercept plus axitinib vs. axitinib alone. Key eligibility criteria are one prior TKI in the first-line setting, ECOG </= 1, and measurable disease. The primary efficacy endpoint is PFS. Secondary endpoints are OS, TTP, ORR, DOR, DCR, and PD biomarkers on archived tumor and serum specimens including BMP9/10 and ALK1 expression. Clinical trial information: NCT01727336.

Antioxidant and hepatoprotective action of Asparagus racemosus Willd. root extracts

The antioxidant activities of the crude hydro-alcoholic extract (CE) and its four fractions viz. methanol (MF), ethyl acetate (EF), n-Butanol (BF), and precipitated aqueous (PAF) of A.racemosus roots tested decreased in the order of EF > MF > CE > BF > PAF when investigated by DPPH free radical scavenging assay. Under iron induced lipid peroxidation almost similar results were observed except that the activity was more in PAF than BF. Hepatoprotective activity of the extracts was also demonstrable in vivo by the inhibition of-CCl4 induced formation of lipid peroxides in the liver of rats by pretreatment with the extracts. CCl4-induced hepatotoxicity in rats, as judged by the raised serum enzymes viz. glutamate oxaloacetate transaminase, glutamate pyruvate transaminase, alkaline phosphatase and total and direct bilirubin as well as oxidant enzyme viz. malon dialdehyde were prevented, while antioxidant enzymes viz. superoxide dismutase, reduced glutathione and catalase were elevated by pretreatment with the extracts, demonstrating the potent hepatoprotective action of the roots of A. racemosus.

A first-in-human phase Ib study to evaluate the MEK inhibitor GDC-0973, combined with the pan-PI3K inhibitor GDC-0941, in patients with advanced solid tumors

2566

Background: Both RAS/RAF/MEK and PI3K/Akt signaling pathways are deregulated in many tumor types. Targeting both pathways may be more efficacious than targeting either pathway alone. In preclinical models, concurrent administration of GDC‑0973, a potent, selective, MEK1/2 inhibitor and GDC-0941, a potent class I PI3K inhibitor, shows improved efficacy compared to either agent alone dosed continuously or intermittently. Methods: A phase Ib dose-escalation study with 3+3 design was initiated in patients (pts) with advanced solid tumors to evaluate the safety and pharmacokinetics (PK) of oral dosing of GDC-0973 and GDC-0941. Pts received: concurrent GDC-0973 + GDC-0941 once daily (qd) on a 21 day on/7 day off (21/7) schedule; intermittent GDC-0973 on Days 1, 4, 8, 11, 15, 18 of a 28 day cycle + GDC-0941 qd on a 21/7 schedule (MEK int); or GDC-0973 + GDC-0941 qd on a 7 day on /7 day off schedule (7/7). Starting doses were 20 mg GDC-0973 + 80 mg GDC-0941 (21/7), 100 mg GDC-0973 + 130 mg GDC-0941 (MEK int); 40 mg GDC-0973 + 130 mg GDC-0941 (7/7). Serial plasma PK samples, FDG-PET, and CT scans were obtained. Results: 78 pts have enrolled. DLTs were G3 lipase (n=1), G4 CPK elevation (n=1). Compared to the 21/7 MTD of 40 mg GDC-0973 + 100 mg GDC-0941, higher doses of GDC-0973 + GDC-0941 were tolerated on the MEK int schedule. Overall, adverse events related to the study drug combination in ≥ 20% pts were diarrhea, rash, nausea, fatigue, vomiting, decreased appetite, dysgeusia, and elevated CPK. Preliminary analysis indicated PK of GDC-0973 and GDC-0941 are not altered when dosed in combination. Of 46 evaluable pts, 26 had an FDG-PET partial metabolic response (≥ 20% decrease in mean SUVmax from baseline) at ≥1 time points. Partial responses were observed in 3 pts (mBRAF melanoma, mBRAF pancreatic ca, mKRAS endometrioid ca); 5 pts had stable disease ≥ 5 months. Conclusions: Combination dosing of GDC‑0973 and GDC-0941 is generally well tolerated, with toxicities similar to those observed in single agent GDC-0973 and GDC-0941 phase 1 trials. There are early signs of anti-tumor activity. Dose escalation on MEK int and 7/7 schedules continues and updated data will be presented.

Modulating effect of Gmelina arborea Linn. on immunosuppressed albino rats

AIM

In the present study, the immunomodulatory effects of roots of Gmelina arborea Linn. were investigated

MATERIALS AND METHODS

Methanolic extract of G. arborea Linn. (MEGA) and its ethyl acetate fraction (EAFME) were used for evaluating the pharmacological activity. The modulating effect was evaluated on humoral and cell-mediated immune response using animal models like cyclophosphamide-induced myelosuppression, delayed-type hypersensitivity (DTH) response, and humoral antibody (HA) titre

RESULTS

Both test extracts produced significant increase in HA titre, DTH response, and levels of total white blood cell count

CONCLUSION

This drug is found to be a potential immunostimulant.

Observations from a 'special selective drive' conducted under National Leprosy Elimination Programme in Karjat taluka and Gadchiroli district of Maharashtra

The special selective drive (SSD) was conducted on a request from the Joint Director of Health Services (Leprosy and TB) Government of Maharashtra. The study team comprised the Foundation for Medical Research (FMR), assisted by a member of the Acworth Leprosy Hospital Society for Research, Rehabilitation and Education in Leprosy and two from Kushtrog Nivaran Samiti (KNS). The drive was conducted in select villages covered by 6 primary health centers (PHCs) in Karjat taluka of Raigad district and 45 PHCs in Gadchiroli district from March to May 2009 and had the cooperation of the district and PHC level staff. The aim was to train and deploy community level workers (CWs) for early leprosy case detection and through them, to create leprosy awareness in the community. A total of 1053 CWs (126 in Karjat taluka, 927 in Gadchiroli district) were given intensive training by the team. The CWs then carried out a one-day house-to-house leprosy awareness drive in their areas and listed persons such 'suspects' in both Karjat taluka (no. = 514) and Gadchiroli district (no. = 1325). Around 40% of 'suspects' presented themselves at the PHCs for examination by the medical team; of these 38 (29%) and 281 (45%) respectively turned out to be previously undetected definite cases of leprosy. The PHC-wise NCDR ranged from 5 - 27/10,000 in Karjat (14/10,000) and 2 - 35/10,000 in Gadchiroli (average 13/10,000), both rates being much higher than the reported State average of 1.1/10,000. There was a high proportion of child cases (14 and 24% respectively) and grade 2 disability (18% and 12% respectively) which indicate continued transmission of leprosy and delayed diagnosis of cases. The study also notes poor diagnostic skills among the PHC staff. Significant shortage and irregular disbursement of MDT from district store PHCs, combined with transport problem which probably contributed to delay in treatment in over 50% of the cases confirmed by the team.

The first international leprosy conference, Berlin, 1897: the politics of segregation

The present paper examines the first attempts to internationalise the problem of leprosy, a subject hitherto overlooked by historians of imperialism and disease. The last decade of the nineteenth century saw many in the civilised countries of the imperialist West gripped by a paranoia about an invasion of leprosy via germ-laden immigrants and returning expatriates who had acquired the infection in leprosy endemic colonial possessions. Such alarmists clamoured for the adoption of vigorous leper segregation policies in such colonies. But the contagiousness of leprosy did not go unquestioned by other westerners. The convocation in Berlin of the first international meeting on leprosy revealed the interplay of differing and sometimes incompatible views about the containment of leprosy by segregation. The roles of officials from several countries, as well as the roles of five protagonists (Albert Ashmead, Jules Goldschmidt, Edvard Ehlers. Armauer Hansen, and Phineas Abraham) in the shaping of the Berlin Conference are here examined.

Correlation of quantitative tests of nerve and target organ dysfunction with skin immunohistology in leprosy

Loss of nociception and hypohidrosis in skin are hallmarks of leprosy, attributed to early invasion by Mycobacterium leprae of Schwann cells related to unmyelinated nerve fibres. We have studied skin lesions and contralateral clinically unaffected skin in 28 patients across the leprosy spectrum with a range of selective quantitative sensory and autonomic tests, prior to biopsy of both sites. Unaffected sites showed normal skin innervation, when antibodies to the pan-neuronal marker PGP (protein gene product) 9.5 were used, with the exception of intraepidermal fibres which were not detected in the majority of cases. Elevation of thermal thresholds and reduced sensory axon-reflex flare responses in affected skin correlated with decreased nerve fibres in the subepidermis, e.g. axon-reflex flux units (means+/-SEM) for no detectable innervation; decreased innervation; and clinically unaffected skin, were 23+/-3.1; 41.2+/-7.3; and 84.5+/-4.0, respectively. Reduced nicotine-induced axon-reflex sweating was correlated with decreased innervation of sweat glands. Where methacholine-induced direct activation of sweat glands was affected, there was inflammatory infiltrate and loss of sweat gland structure. This study demonstrates a correlation between selective nerve dysfunction on clinical tests and morphological changes in skin, irrespective of the type of leprosy, and is the first to show that loss of sweating in leprosy may result either from decreased innervation and/or involvement of the sweat glands. The findings have implications for the selection and monitoring of patients with leprosy in clinical trials which aim to restore cutaneous function.

Severe pan-sensory neuropathy in leprosy

The sensory loss which occurs in leprosy is essentially cutaneous, resulting from centripetally ascending infection, the host cellular response and fibrosis, from dermal to certain mixed nerves. The hallmark is pain/temperature and touch/pressure loss. Muscle denervation is a byproduct of mixed nerve involvement. Leprous sensory and motor neuropathy presents a stereotyped picture, with preservation of position sense, noninvolvement of the large girdle muscles, and retained deep tendon reflexes. We report clinical and investigative details of 7 patients (3 males, 4 females) with mild-to-moderate polyneuritic leprosy who manifested severe proprioceptive loss in the upper per limbs; the lower limbs were similarly affected in 4 of them. Tendon reflexes were absent in the ataxic limbs. No other cause was found for the ataxia. Electrophysiological studies confirmed damage to large cutaneous and muscle afferents, and a normal EMG pattern in hip and shoulder muscles. Of great interest was the histology of a lumbar sensory ganglion biopsied in a severely disabled patient. There was extensive neuron loss and degeneration and reactive proliferation of capsular cells ("nodules of Nageotte"), an inflammatory focus of lymphocytes, and no bacilli. This suggests to us that the proprioceptive loss in these patients could well be the result of an unusual "leprous ganglionitis." Further clarification of the mechanism of ganglion degeneration and the frequency of inflammation could come from immunohistology of tissues from African green monkeys with experimental polyneuritic leprosy.

Simplified technique for recording human cortical & spinal evoked muscle potentials

Muscle responses evoked on transcranial stimulation of the motor cortex (corticomotor) and motor roots (spinal) were studied in 20 healthy volunteers using a simplification of Rossini's technique and conventional EMG equipment. Cortical motor responses were consistently obtained from the contralateral upper limb with tolerable stimuli. Lower limb motor responses were inconsistent and sometimes required uncomfortably high stimulus strengths. In the upper limbs, peripheral conduction time (PCT) was estimated by the latency of the response to spinal stimulation. A comparable measure of PCT was obtained for the abductor pollicis brevis (APB) from the F-responses. The difference between the latency of the corticomotor response and the PCT was considered to represent central motor conduction time (CMCT). Corticomotor latencies were: APB 18.51 +/- 1.1 msec, biceps 9.77 +/- 0.46 msec and tibialis anterior 26.5 +/- 2.9 msec. CMCT from cortex to C8/T1 segments (APB) was 4.68 +/- 0.6 msec and between cortex and C5/C6 (biceps) 4.24 +/- 0.42 msec.

Dapsone neuropathy--report of three cases and pathologic features of a motor nerve

We report the clinical features, electrophysiologic findings, and dapsone and isoniazid excretion studies in three young people who ingested excessive amounts (2-4 times the prescribed dose) of dapsone for hypopigmented macules and who developed, subacutely, progressive motor neuropathy a few months later. Pathologic studies on a biopsied motor nerve confirmed the electrophysiologic conclusion of distal motor axonopathy. All made a rapid recovery in a few months after dapsone was stopped, although electrical abnormalities persisted. One patient was a rapid acetylator of isoniazid.

Surgery on the peripheral nerves in leprosy

In a short review the operative possibilities of peripheral nerve involvement in leprosy concerning pain and paralysis are discussed. External, extraneural and funicular neurolysis, transposition, and treatment of nerve abscess proved to be the methods of choice.

An attempt to influence nerve degeneration and regeneration by using macrophage cell homogenate

The effect of the contents of activated macrophages on the degenerative/regenerative process in the mouse sciatic nerve was investigated as a possible model for leprosy. The whole cellular homogenate or saline was injected every week around physically impaired (to bypass the perineurial barrier) and normal nerves. Recovery of the nerve function was monitored clinically and electromyographically. After 14 weeks animals were sacrificed and nerves were processed for histology. The data obtained from 134 experimental and control nerves were rated and analysed statistically. The course of the nerve regeneration in the physically impaired nerve with and without homogenate was found to be similar. One of the reasons for this could be insufficient concentration of the homogenate in the endoneurial space.

Electrophysiologic and histologic studies in leprosy and some acrodystrophic neuropathies

In vitro electrophysiologic and light microscopic studies were carried out on the sural nerve in six patients with non-leprous neuropathy with plantar ulceration and in six patients with various types of leprous neuropathy. In the non-leprous group (with congenital and acquired neuropathy) the abnormalities in the compound action potentials of the myelinated (large and small) fibers were usually more striking than those in the unmyelinated fibers potentials. In the leprous neuropathies, on the other hand, the three major fiber groups tended to be involved indiscriminately, the unmyelinated fiber potential being as liable to abnormality as the myelinated fiber potentials. Histologically the nerve fiber damage in the congenital neuropathies appeared to be moderate to gross involvement of the myelinated fibers without the prominent demyelination and degeneration/regeneration seen in leprosy and the other acquired neuropathies. Leprous neuropathy showed, besides fiber abnormalities, the simultaneous deleterious effects of inflammation and fibrosis. It is a matter for speculation whether disturbed conduction in the large myelinated touch-pressure mediating fibers contributes significantly to impaired pain perception (mediated by small fibers) and plantar ulceration in leprosy and other acrodystrophic neuropathies.

Quantitative electromyography using automatic analysis--diagnostic utility of turns per unit amplitude

Quantitative electromyographic (QEMG) data from 3 muscles recorded with a 50-micronV threshold for the turns and amplitude measurements are presented. Using turns per unit amplitude as the index, consistent and comparable readings were recorded from abductor digiti minimi, biceps brachii and vastus medialis in normal subjects, namely 1.132 +/- 0.08 (31 subjects), 1.059 +/- 0.122 (31 subjects) and 1.007 +/- 0.088 (11 subjects), respectively. It is shown here that the diagnostic yield increases when all 3 values, namely, turns/s, average amplitude and turns/unit amplitude are considered in conjunction rather than considering the first 2 alone.