A Single-Arm, Open-Label Phase II Study of ONC201 in Recurrent/Refractory Metastatic Breast Cancer and Advanced Endometrial Carcinoma

BACKGROUND

ONC201 is a small molecule that can cause nonapoptotic cell death through loss of mitochondrial function. Results from the phase I/II trials of ONC201 in patients with refractory solid tumors demonstrated tumor responses and prolonged stable disease in some patients.

METHODS

This single-arm, open-label, phase II clinical trial evaluated the efficacy of ONC201 at the recommended phase II dose (RP2D) in patients with recurrent or refractory metastatic breast or endometrial cancer. Fresh tissue biopsies and blood were collected at baseline and at cycle 2 day 2 for correlative studies.

RESULTS

Twenty-two patients were enrolled; 10 patients with endometrial cancer, 7 patients with hormone receptor-positive breast cancer, and 5 patients with triple-negative breast cancer. The overall response rate was 0%, and the clinical benefit rate, defined by complete response (CR) + partial response (PR) + stable disease (SD), was 27% (n = 3/11). All patients experienced an adverse event (AE), which was primarily low grade. Grade 3 AEs occurred in 4 patients; no grade 4 AEs occurred. Tumor biopsies did not show that ONC201 consistently induced mitochondrial damage or alterations in tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) or the TRAIL death receptors. ONC201 treatment caused alterations in peripheral immune cell subsets.

CONCLUSION

ONC201 monotherapy did not induce objective responses in recurrent or refractory metastatic breast or endometrial cancer at the RP2D dose of 625 mg weekly but had an acceptable safety profile (ClinicalTrials.gov Identifier: NCT03394027).

Phase I Study and Cell-Free DNA Analysis of T-DM1 and Metronomic Temozolomide for Secondary Prevention of HER2-Positive Breast Cancer Brain Metastases

PURPOSE

Preclinical data showed that prophylactic, low-dose temozolomide (TMZ) significantly prevented breast cancer brain metastasis. We present results of a phase I trial combining T-DM1 with TMZ for the prevention of additional brain metastases after previous occurrence and local treatment in patients with HER2+ breast cancer.

PATIENTS AND METHODS

Eligible patients had HER2+ breast cancer with brain metastases and were within 12 weeks of whole brain radiation therapy (WBRT), stereotactic radiosurgery, and/or surgery. Standard doses of T-DM1 were administered intravenously every 21 days (3.6 mg/kg) and TMZ was given orally daily in a 3+3 phase I dose escalation design at 30, 40, or 50 mg/m2, continuously. DLT period was one 21-day cycle. Primary endpoint was safety and recommended phase II dose. Symptom questionnaires, brain MRI, and systemic CT scans were performed every 6 weeks. Cell-free DNA sequencing was performed on patients' plasma and CSF.

RESULTS

Twelve women enrolled, nine (75%) with prior SRS therapy and three (25%) with prior WBRT. Grade 3 or 4 AEs included thrombocytopenia (1/12), neutropenia (1/12), lymphopenia (6/12), and decreased CD4 (6/12), requiring pentamidine for Pneumocystis jirovecii pneumonia prophylaxis. No DLT was observed. Four patients on the highest TMZ dose underwent dose reductions. At trial entry, 6 of 12 patients had tumor mutations in CSF, indicating ongoing metastatic colonization despite a clear MRI. Median follow-up on study was 9.6 m (2.8-33.9); only 2 patients developed new parenchymal brain metastases. Tumor mutations varied with patient outcome.

CONCLUSIONS

Metronomic TMZ in combination with standard dose T-DM1 shows low-grade toxicity and potential activity in secondary prevention of HER2+ brain metastases.

First-in-human phase 1 clinical trial of anti-core 1 O-glycans targeting monoclonal antibody NEO-201 in treatment-refractory solid tumors

BACKGROUND

NEO201 is a humanized IgG1 monoclonal antibody (mAb) generated against tumor-associated antigens from patients with colorectal cancer. NEO-201 binds to core 1 or extended core 1 O-glycans expressed by its target cells. Here, we present outcomes from a phase I trial of NEO-201 in patients with advanced solid tumors that have not responded to standard treatments.

METHODS

This was a single site, open label 3 + 3 dose escalation clinical trial. NEO-201 was administered intravenously every two weeks in a 28-day cycle at dose level (DL) 1 (1 mg/kg), DL 1.5 (1.5 mg/kg) and DL 2 (2 mg/kg) until dose limiting toxicity (DLT), disease progression, or patient withdrawal. Disease evaluations were conducted after every 2 cycles. The primary objective was to assess the maximum tolerated dose (MTD) and recommended phase 2 dose (RP2D) of NEO-201. The secondary objective was to assess the antitumor activity by RECIST v1.1. The exploratory objectives assessed pharmacokinetics and the effect of NEO-201 administration on immunologic parameters and their impact on clinical response.

RESULTS

Seventeen patients (11 colorectal, 4 pancreatic and 2 breast cancers) were enrolled; 2 patients withdrew after the first dose and were not evaluable for DLT. Twelve of the 15 patients evaluable for safety discontinued due to disease progression and 3 patients discontinued due to DLT (grade 4 febrile neutropenia [1 patient] and prolonged neutropenia [1 patient] at DL 2, and grade 3 prolonged (> 72 h) febrile neutropenia [1 patient] at DL 1.5). A total of 69 doses of NEO-201 were administered (range 1-15, median 4). Common (> 10%) grade 3/4 toxicities occurred as follows: neutropenia (26/69 doses, 17/17 patients), white blood cell decrease (16/69 doses, 12/17 patients), lymphocyte decrease (8/69 doses, 6/17 patients). Thirteen patients were evaluable for disease response; the best response was stable disease (SD) in 4 patients with colorectal cancer. Analysis of soluble factors in serum revealed that a high level of soluble MICA at baseline was correlated with a downregulation of NK cell activation markers and progressive disease. Unexpectedly, flow cytometry showed that NEO-201 also binds to circulating regulatory T cells and reduction of the quantities of these cells was observed especially in patients with SD.

CONCLUSIONS

NEO-201 was safe and well tolerated at the MTD of 1.5 mg/kg, with neutropenia being the most common adverse event. Furthermore, a reduction in the percentage of regulatory T cells following NEO-201 treatment supports our ongoing phase II clinical trial evaluating the efficiency of the combination of NEO-201 with the immune checkpoint inhibitor pembrolizumab in adults with treatment-resistant solid tumors.

TRIAL REGISTRATION

NCT03476681 . Registered 03/26/2018.

Intraperitoneal Monocytes plus IFNs as a Novel Cellular Immunotherapy for Ovarian Cancer: Mechanistic Characterization and Results from a Phase I Clinical Trial

PURPOSE

Ovarian cancer is the most lethal gynecologic cancer and intrinsically resistant to checkpoint immunotherapies. We sought to augment innate immunity, building on previous work with IFNs and monocytes.

PATIENTS AND METHODS

Preclinical experiments were designed to define the mechanisms of cancer cell death mediated by the combination of IFNs α and γ with monocytes. We translated these preclinical findings into a phase I trial of autologous IFN-activated monocytes administered intraperitoneally to platinum-resistant or -refractory ovarian cancer patients.

RESULTS

IFN-treated monocytes induced caspase 8-dependent apoptosis by the proapoptotic TRAIL and mediated by the death receptors 4 and 5 (DR4 and DR5, respectively) on cancer cells. Therapy was well tolerated with evidence of clinical activity, as 2 of 9 evaluable patients had a partial response by RECIST criteria, and 1 additional patient had a CA-125 response. Upregulation of monocyte-produced TRAIL and cytokines was confirmed in peripheral blood. Long-term responders had alterations in innate and adaptive immune compartments.

CONCLUSIONS

Given the mechanism of cancer cell death, and the acceptable tolerability of the clinical regimen, this platform presents a possibility for future combination therapies to augment anticancer immunity. See related commentary by Chow and Dorigo, p. 299.

Abstract P1-21-06: Phase I study of T-DM1 and metronomic temozolomide in secondary prevention of HER2+ breast cancer brain metastases following local radiation therapy

Background: The incidence of breast cancer brain metastases is rising, and, these lesions in the central nervous system (CNS) and their treatments cause physical and neurocognitive impairment. Only modest incremental advances in progression free survival have been achieved with drugs to treat CNS lesions, while nearly half of the patients who receive SRS will develop new brain metastases within 1 year. In murine models of breast cancer, we demonstrated that low doses of temozolomide (TMZ) administered in a prophylactic, metronomic fashion significantly prevented development of brain metastases. No effect, however, was seen in established brain metastases or systemic breast cancer metastases. We hypothesize that low dose, metronomic TMZ will prevent the outgrowth of brain lesions in HER2+ patients, when added to an active anti-HER2 treatment. We present here the results of the phase I trial combining T-DM1 to TMZ for the prevention of additional brain metastases after their first occurrence and local treatment. Methods: Eligible patients had HER2+ breast cancer with brain metastases and were within 12 weeks of local brain metastases therapy (WBRT, SRS and or surgery), with PS 0-2 and adequate end organ function. Standard doses of T-DM1 were administered IV every 21 days (3.6 mg/kg) and TMZ was given PO daily in a 3+3 design at 30, 40 or 50 mg/m2, continuously. The DLT period was one 21d cycle. Safety was assessed by CTCAEv4.0 and response by RECISTv1.1 and RANO-BM. Brain MRI and systemic CT scans were performed every 6 weeks. Blood samples for correlatives evaluation were collected at baseline and every cycle while on trial. CSF was collected at baseline and C3D1 for all patients. Questionnaires (MDASI-BT and PROMIS®) for evaluation of symptoms and quality of life were completed every 6 weeks. Results: Twelve women with median age 55.5yr (44-67) were enrolled. Only 3 (25%) patients had HR+/HER2+ tumors at initial diagnosis. Nine (75%) patients presented stages II and III disease at initial diagnosis, and developed brain metastases at the diagnosis of first recurrence. Nine (75%) patients received SRS therapy and 3 (25%) received WBRT prior to trial enrollment. Grade 3 or 4 AEs included thrombocytopenia (1/12), neutropenia (1/12), lymphopenia (6/12) and decreased CD4 (6/12), requiring pentamidine for PCP prophylaxis. No DLT was observed. Four patients underwent dose reductions (thrombocytopenia, fatigue and peripheral neuropathy), all of them enrolled on the highest TMZ dose. Median follow-up on study is now 9.6m (1.2-32) and no patient developed new parenchymal brain metastases. Five patients remain on study, while 7 are off study due to progression at previously irradiated CNS lesion (2), progression of systemic disease (2), focal leptomeningeal involvement (1), new cancer (1) and persistent thrombocytopenia (1). Completion rates for the questionnaires were 99% by Cycle 15 (81 completed out of expected 82) and 90% by Cycle 41 (123/137), and will be reported at presentation. Conclusion: Metronomic TMZ in combination with standard dose T-DM1 is tolerable and shows promising activity in secondary prevention of HER2+ brain metastases. Systematic longitudinal symptom assessments in breast cancer patients with brain metastasis are feasible. A randomized phase II expansion of this trial with T-DM1 or T-Dxd +/- TMZ is planned.

Citation Format: Alexandra S Zimmer, Seth Steinberg, Mark Gilbert, Terri Armstrong, Eric Burton, Nicole Houston, Dee Dee Smart, Nadia Biassou, John Butman, Priscilla K Brastianos, Carey K Anders, Stanley Lipkowitz, Patricia S Steeg. Phase I study of T-DM1 and metronomic temozolomide in secondary prevention of HER2+ breast cancer brain metastases following local radiation therapy [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr P1-21-06.

Temozolomide in secondary prevention of HER2-positive breast cancer brain metastases

Brain metastases occur in up to 25-55% of patients with metastatic HER2-positive breast cancer. Standard treatment has high rates of recurrence or progression, limiting survival and quality of life in most patients. Temozolomide (TMZ) is known to penetrate the blood-brain barrier and is US FDA approved for treatment of glioblastoma. Our group has demonstrated that low doses of TMZ administered in a prophylactic, metronomic fashion can significantly prevent development of brain metastases in murine models of breast cancer. Based on these findings, we initiated a secondary-prevention clinical trial with oral TMZ given to HER2-positive breast cancer patients with brain metastases after recent local treatment in combination with T-DM1 for systemic control of disease. Primary end point is freedom from new brain metastases at 1 year. (NCT03190967).

Phase I/Ib study of olaparib and carboplatin in heavily pretreated recurrent high-grade serous ovarian cancer at low genetic risk

Purpose: To investigate maximum tolerated dose (MTD), activity and predictive biomarkers of olaparib with carboplatin in BRCA wild-type (BRCAwt) high grade serous ovarian carcinoma (HGSOC) patients. Methods: A 3+3 dose escalation study examined olaparib capsules (400 mg twice daily [BID], days 1-7) with carboplatin (AUC3-5 on day 1) every 21 days for 8 cycles, followed by olaparib 400 mg BID maintenance. Blood and tumor biopsy samples were collected pre- and on-treatment in the expansion cohort for PAR levels and proteomic endpoints. Results: 30 patients (median 7 prior regimens [2-12], 63% (19/30) platinum-resistant) were enrolled. Dose-limiting toxicity was thrombocytopenia/neutropenia, and infection with carboplatin AUC5 (2/6 patients). MTD was olaparib 400 mg BID + carboplatin AUC4. Grade 3/4 adverse events (>10%) included neutropenia (23%), thrombocytopenia (20%), and anemia (13%). Five of 25 (20%) evaluable patients had partial response (PR; median 4.5 months [3.3-9.5]). Clinical benefit rate (PR + stable disease ≥4 months) was 64% (16/25). A greater decrease in tissue PAR levels was seen in the clinical benefit group versus no benefit (median normalized linear change -1.84 [-3.39- -0.28] vs 0.51 [-0.27- 1.29], p = 0.001) and a DNA repair score by proteomics did not correlate with response. Conclusions: The olaparib and carboplatin combination is tolerable and has clinical benefit in subsets of heavily pretreated BRCAwt HGSOC, independent of platinum sensitivity.

Abstract OT2-06-01: Phase I/II study of T-DM1 alone versus T-DM1 and metronomic temozolomide in secondary prevention of HER2-Positive breast cancer brain metastases following stereotactic radiosurgery

Background: Brain metastases occur in up to 25-40% of HER2+ breast cancer patients. Standard treatment is limited to surgery or stereotactic radiosurgery (SRS) and/or whole brain radiation therapy (WBRT), with high levels of recurrence or progression, limiting survival and quality of life in most patients. Our group has demonstrated that low doses of temozolomide (TMZ) administered in a prophylactic, metronomic fashion can significantly prevent development of brain metastases in murine models of breast cancer. Based on these findings, we propose a secondary-prevention clinical trial.

Trial Design: Phase I/II open label study. Phase I will follow a standard 3+3 design: T-DM1 3.6 mg/kg IV every 21 days plus TMZ 30, 40 or 50 mg/m2 daily. Phase II: randomization T-DM1 3.6 mg/kg versus T-DM1 3.6mg/kg plus TMZ at recommended phase 2 dose (RP2D). Patients will undergo radiology guided lumbar puncture at baseline and after 6 weeks of treatment (C3D1) for correlative studies, brain MRI, systemic restaging CTs, and questionnaires for evaluation of symptoms and quality of life (MDASI-BT and PROMIS®) every 6 weeks.

Eligibility: HER2+ breast cancer with ≤3 brain metastases, treated with SRS and/or resection ≤6 weeks before enrollment, no leptomeningeal metastases, no previous WBRT, able to complete brain MRI with contrast evaluations, willing to undergo lumbar puncture, ECOG ≤2 and adequate organ and marrow function. HBV, HCV or HIV-positive patients are ineligible.

Specific Aims: Phase I: to identify the maximum tolerated dose (MTD) of TMZ combined with T-DM1. Phase II: to determine if the combination regimen of T-DM1 and TMZ improves the recurrence-free incidence from distant new brain metastases at one year as compared to T-DM1 alone. Biomarkers, including cell free DNA sequencing from CSF, serum and tumor block, serum markers for neuroinflammation, and patient reported outcomes, will be analyzed in an exploratory fashion.

Statistical Methods: Phase I, MTD will be identified based on the dose level at which 0 or 1 patient in 6 has a DLT. Phase II, to test whether TMZ will increase RFS from 50% to 65% at 12 months. RFS Kaplan-Meier curves will be created for each of the randomized arms and compared using a one-tailed log-rank test, with a one-sided 0.10 significance level of interest to be detected. Patients will be stratified for number of brain lesions and status of systemic metastases (controlled or not).

Target Accrual: 49 evaluable patients per arm (total 98), plus 9 to 18 patients during phase I. Trial will open in Summer 2017, at NIH in Bethesda, MD.

Contact Information: Principal Investigator: Alexandra S Zimmer, MD alexandra.zimmer@nih.gov

Citation Format: Zimmer AS, Gril B, Steinberg S, Smart D, Gilbert M, Armstrong T, Xiao L, Houston N, Biassou N, Brastianos P, Carter S, Lyden DC, Lipkowitz S, Steeg P. Phase I/II study of T-DM1 alone versus T-DM1 and metronomic temozolomide in secondary prevention of HER2-Positive breast cancer brain metastases following stereotactic radiosurgery [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr OT2-06-01.

Safety and Clinical Activity of the Programmed Death-Ligand 1 Inhibitor Durvalumab in Combination With Poly (ADP-Ribose) Polymerase Inhibitor Olaparib or Vascular Endothelial Growth Factor Receptor 1-3 Inhibitor Cediranib in Women's Cancers: A Dose-Escalation, Phase I Study

Purpose Data suggest that DNA damage by poly (ADP-ribose) polymerase inhibition and/or reduced vascular endothelial growth factor signaling by vascular endothelial growth factor receptor inhibition may complement antitumor activity of immune checkpoint blockade. We hypothesize the programmed death-ligand 1 (PD-L1) inhibitor, durvalumab, olaparib, or cediranib combinations are tolerable and active in recurrent women's cancers. Patients and Methods This phase I study tested durvalumab doublets in parallel 3 + 3 dose escalations. Durvalumab was administered at 10 mg/kg every 2 weeks or 1,500 mg every 4 weeks with either olaparib tablets twice daily or cediranib on two schedules. The primary end point was the recommended phase II dose (RP2D). Response rate and pharmacokinetic analysis were secondary end points. Results Between June 2015 and May 2016, 26 women were enrolled. The RP2D was durvalumab 1,500 mg every 4 weeks with olaparib 300 mg twice a day, or cediranib 20 mg, 5 days on/2 days off. No dose-limiting toxicity was recorded with durvalumab plus olaparib. The cediranib intermittent schedule (n = 6) was examined because of recurrent grade 2 and non-dose-limiting toxicity grade 3 and 4 adverse events (AEs) on the daily schedule (n = 8). Treatment-emergent AEs included hypertension (two of eight), diarrhea (two of eight), pulmonary embolism (two of eight), pulmonary hypertension (one of eight), and lymphopenia (one of eight). Durvalumab plus intermittent cediranib grade 3 and 4 AEs were hypertension (one of six) and fatigue (one of six). Exposure to durvalumab increased cediranib area under the curve and maximum plasma concentration on the daily, but not intermittent, schedules. Two partial responses (≥15 months and ≥ 11 months) and eight stable diseases ≥ 4 months (median, 8 months [4 to 14.5 months]) were seen in patients who received durvalumab plus olaparib, yielding an 83% disease control rate. Six partial responses (≥ 5 to ≥ 8 months) and three stable diseases ≥ 4 months (4 to ≥ 8 months) were seen in 12 evaluable patients who received durvalumab plus cediranib, for a 50% response rate and a 75% disease control rate. Response to therapy was independent of PD-L1 expression. Conclusion To our knowledge, this is the first reported anti-PD-L1 plus olaparib or cediranib combination therapy. The RP2Ds of durvalumab plus olaparib and durvalumab plus intermittent cediranib are tolerable and active. Phase II studies with biomarker evaluation are ongoing.

Sequence-Specific Pharmacokinetic and Pharmacodynamic Phase I/Ib Study of Olaparib Tablets and Carboplatin in Women's Cancer

Purpose: Our preclinical studies showed that the PARP inhibitor, olaparib, prior to carboplatin attenuated carboplatin cytotoxicity. We evaluated sequence-specific pharmacokinetic and pharmacodynamic effects, safety, and activity of the combination.Experimental Design: Eligible patients had metastatic or recurrent women's cancer. Olaparib tablets were introduced (100 or 200 mg twice daily, days 1-7) in a 3 + 3 dose escalation with carboplatin AUC4 or 5 every 21 days, up to eight cycles, followed by olaparib 300 mg twice daily maintenance. Patients were randomly assigned to starting schedule: cohort A (olaparib days 1-7, carboplatin on day 8) or B (carboplatin on day 1, olaparib days 2-8) during cycle 1. Patients received the reversed scheme in cycle 2. Blood was collected for olaparib pharmacokinetics, platinum-DNA adducts, comet assay, and PAR concentrations. The primary objectives were to examine schedule-dependent effects on olaparib pharmacokinetics and platinum-DNA adducts.Results: A total of 77 (60 ovarian, 14 breast, and 3 uterine cancer) patients were treated. Dose-limiting toxicity was thrombocytopenia and neutropenia, defining olaparib 200 mg twice daily + carboplatin AUC4 as the MTD. Olaparib clearance was increased approximately 50% when carboplatin was given 24 hours before olaparib. In vitro experiments demonstrated carboplatin preexposure increased olaparib clearance due to intracellular olaparib uptake. Quantities of platinum-DNA adducts were not different as a function of the order of drug administration. Responses included 2 CRs and 31 PRs (46%) with a higher RR in BRCA mutation carriers compared with nonmutation carriers (68% vs. 19%).Conclusions: Tablet olaparib with carboplatin is a safe and active combination. Carboplatin preexposure causes intracellular olaparib accumulation reducing bioavailable olaparib, suggesting carboplatin should be administered prior to olaparib. Clin Cancer Res; 23(6); 1397-406. ©2016 AACR.

Abstract 2043: Effects of 24-h carboplatin pretreatment on olaparib clearance in women's cancers using noncompartmental and population pharmacokinetic analyses

Background: Olaparib (OLA) is a PARP inhibitor approved for use in deleterious germline BRCA mutated recurrent or refractory ovarian cancer. Combining OLA with carboplatin (CARBO) could have additive effects based on platinum-DNA adducts requiring PARP for DNA repair. Preclinical data suggest greater cytotoxicity when CARBO is given prior to OLA. However, the optimal treatment sequence of these agents has not been studied previously in patients. We therefore investigated: 1) the effects of CARBO treatment on the pharmacokinetics (PK) and pharmacodynamics (PD) of OLA; 2) in vitro mechanisms of the interaction between CARBO and OLA.

Methods: Clinical PK and PD data of OLA were obtained from 58 patients with confirmed recurrent or refractory women's cancers participating in a two arm, parallel design, phase 1 trial (NCT01237067). In cycle 1 OLA tablets (200 mg BID) were given for 7 days either followed by CARBO (AUC 4) on day 8 (arm A) or after CARBO on day 1 (Arm B). In cycle 2 the arms received the reversed scheme. PK of OLA were assessed in both cycles by noncompartmental (NCA) and population pharmacokinetic (PPK) analyses. For PK/PD analyses, PAR levels were measured at baseline and 24 h after the first OLA dose. In vitro mechanistic studies were carried out by incubating whole human blood and avian DT40 PARP-1 KO cells with 10 μM CARBO for 24 h, followed by 1h-treatment of isolated PBMCs and PARP-1 KO cells with 10 μM OLA. Intracellular OLA concentrations were determined using UPLC-MS/MS.

Results: Both NCA and PPK analyses showed a ∼50% increase in OLA clearance when CARBO was administered 24-h prior (P<0.02). The PPK model included a lag time parameter (P = 1.1E-18), a second absorption compartment (P = 7.7E-27), a single elimination compartment, and accounted for covariance among the clearance and volume parameters (P = 6.7E-7). Presence of CARBO was the only significant covariate affecting OLA clearance (P = 1.9E-13). Final estimates for clearance and volume of distribution were 6.8 L/h and 33 L, respectively, which were comparable with related reports. There were no trends between PK data and PAR levels, nor did the presence of CARBO affect PAR levels (P = 0.89). PBMC experiments showed that 24-h pretreatment with CARBO significantly increased intracellular OLA concentrations by more than 30% compared with control samples (P = 0.013). PARP-1 KO cells confirmed that intracellular PARP expression was not related to the increased OLA uptake. Possibly, CARBO affects other intracellular targets or transporters leading to increased intracellular uptake of OLA from the bloodstream.

Conclusion: This is the first known PK analysis showing a significant increase in OLA clearance after pretreatment with CARBO, possibly leading to subtherapeutic plasma concentrations of OLA. Preclinical experiments are ongoing to reveal the exact pharmacological mechanisms of this interaction.

Citation Format: Andrew K.L. Goey, Cody J. Peer, Tristan M. Sissung, Jeffrey Roth, Shandiz Shahbazi, Jeffers Nguyen, Christina M. Annunziata, Nicole Houston, Elise C. Kohn, Jung-Min Lee, William D. Figg. Effects of 24-h carboplatin pretreatment on olaparib clearance in women's cancers using noncompartmental and population pharmacokinetic analyses. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 2043.

Pharmacodynamic markers and clinical results from the phase 2 study of the SMAC mimetic birinapant in women with relapsed platinum-resistant or -refractory epithelial ovarian cancer

BACKGROUND

Inhibitors of apoptosis proteins (IAPs) are key regulators of apoptosis and are frequently dysregulated in ovarian cancer. It was hypothesized that blocking IAPs with birinapant would increase tumor cell death and result in objective responses for women with platinum-refractory and -resistant ovarian cancer.

METHODS

In this phase 2, Cancer Therapy Evaluation Program-sponsored study, patients received birinapant at 47 mg/m(2) on days 1, 8, and 15 of 28-day cycles. Pharmacokinetics were obtained during cycle 1. Plasma, peripheral blood mononuclear cells (PBMCs), and percutaneous tumor biopsy samples were collected before cycle 1 and after 6 weeks. The primary endpoint was an objective response or progression-free survival lasting greater than 6 months in a mini-max design.

RESULTS

Eleven patients received birinapant; after this, accrual was terminated for lack of a clinical benefit. Birinapant was well tolerated, with predominantly grade 2 adverse events and 1 case of grade 3 lymphopenia. Pretreatment biopsy samples and PBMCs were collected; paired posttreatment biopsy samples and PBMCs were collected from 7 and 10 patients, respectively. There was consistent downregulation of cellular inhibitor of apoptosis protein 1 in tumors (P = .016) and PBMCs (P < .01). Procaspase 3 also decreased in tumors (P = .031) and PBMCs (P < .01); cleaved caspase 3 colocalized with H2A histone family member X (γ-H2AX) in tumors after birinapant exposure. Peripheral T and B cells decreased significantly after treatment, but natural killer cells did not (P = .04, P = .05, and P = .43, respectively).

CONCLUSIONS

Birinapant shows consistent target suppression in vivo without single-agent antitumor activity in this small population. Single-agent pharmacodynamics are necessary to understand the drug's mechanism of action and set the stage for rational combination therapy. Preclinical studies are ongoing to identify optimal synergistic combinations for future clinical trials.

Abstract CT326: Pharmacokinetic/pharmacodynamic study of sequence specificity of the PARP inhibitor, olaparib and carboplatin in recurrent women's cancers

Background: Olaparib/carboplatin are active in gBRCA1/2m+ or BRCA-like breast and ovarian cancer (Br/OvCa). Our in vitro data suggest that pretreatment with olaparib before carboplatin attenuates C-induced DNA double stranded breaks (DSBs) and cytotoxicity. We hypothesize olaparib/carboplatin sequence may affect DNA DSBs and toxicity in pts.

Methods: Eligible pts had recurrent women's cancers, normal end-organ function, and evaluable disease. Pts were randomized to arm A or B for intra-pt and inter-cohort analysis of PK/PD endpoints. 21 pts were required per arm for 80% power to determine one SD difference between arms. PBMCs were collected prior to and 24hrs after olaparib or carboplatin on cyc 1&2 for comet DNA damage assay and PAR incorporation ELISA. Toxicity was evaluated q3 wks, and response q2 cyc by RECISTv1.1.

Results: 59 women (age 59 [25-74]; 47 OvCa (26 gBRCAm+)/10 triple negative BrCa [TNBC; 4 gBRCAm+]/1 uterine carcinosarcoma/1 endometrial Ca) were treated. All had prior therapy (median 5[2-14]). Intra-pt comparisons of PD endpoints indicated olaparib/carboplatin yields greater DNA DSBs than olaparib or carboplatin alone (median fold change compared to baseline; 1.21+/- 0.30 SD v. 1.13 or 0.97 [arm A], 1.33 +/- 0.67 SD v. 1.02 or 1.04 [arm B], both p&lt;0.05). Intra-pt and inter-cohort comparisons show no significant differences in DNA DSBs, PAR incorporation and frequencies of Gr3/4 AEs as a function of the order of the schedule. Gr3/4 AEs included neutropenia (22%), anemia (12%), thrombocytopenia (10%), and carboplatin hypersensitivity (3%). Responses (54pts) included 1 CR (2%, 23mo; TNBC) and 23 PR (43%, 9[5-15]mo; 20 OvCa/3 TNBC). gBRCAm+ pts had a higher response rate (RR; 1CR/19 PR) compared to BRCAwt/unknown (4 PR; 65% v. 17%, p&lt;0.001).

Conclusions: Combination O/C induced greater DNA damage than single agents, consistent with the higher than expected RR. However, the O/C sequence did not impact DNA damage, PAR incorporation or toxicity. Olaparib tablets 200mg bid x 7d with carboplatin AUC 4 q 21d is active and tolerable in recurrent women's cancers, especially for gBRCAm+ pts. (NCT01237067)

Treatment schedule armsCycle (cyc) 1Cyc 2Cyc 3-8Cyc 9+Arm AO tablet 200mg bid d1-7⇒C AUC4 d8C AUC4 d1⇒O tablet 200mg bid d2-8O tablet 200mg bid d1-7, C AUC4 d1or2maintenance O tablet 300mg bid

Citation Format: Victoria L. Chiou, Christina Annunziata, Stanley Lipkowitz, Lori Minasian, Nicolas Gordon, Minshu Yu, Seth Steinberg, Nicole Houston, Elise Kohn, Jung-min Lee. Pharmacokinetic/pharmacodynamic study of sequence specificity of the PARP inhibitor, olaparib and carboplatin in recurrent women's cancers. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr CT326. doi:10.1158/1538-7445.AM2015-CT326

CECs and IL-8 Have Prognostic and Predictive Utility in Patients with Recurrent Platinum-Sensitive Ovarian Cancer: Biomarker Correlates from the Randomized Phase-2 Trial of Olaparib and Cediranib Compared with Olaparib in Recurrent Platinum-Sensitive Ovarian Cancer

OBJECTIVE

Olaparib (O), a polyADPribose polymerase (PARP) inhibitor, and cediranib (C), a VEGF receptor (VEGFR)1-3 inhibitor together had greater activity than O alone in women with recurrent platinum-sensitive ovarian cancer (OvCa). The objective of this study is to identify potential lead biomarker candidates for response to O + C in the setting of a multi-institutional phase II study of O with and without C in recurrent platinum-sensitive OvCa.

METHODS

A self-selected group of patients participated in a prospectively planned exploratory biomarker substudy of the randomized phase II study of O versus O + C. Whole blood for peripheral blood mononuclear cell (PBMC) and plasma isolation was collected prior to and on day 3 of treatment. Quantitation of circulating endothelial cells (CEC), IL-6, IL-8, VEGF, and soluble VEGFR-2 plasma concentrations, and polyADPribose (PAR) incorporation were performed. Single nucleotide polymorphism analysis of XRCC1 280H, R194W, and Q399R was done. Dynamic contrast-enhanced-magnetic resonance imaging (DCE-MRI) was performed at baseline and day 3 of treatment. Parameter changes were compared between the two arms using an exact Wilcoxon rank sum test. Kaplan-Meier and log-rank tests were used to examine survival outcome.

RESULTS

Thirteen patients elected to participate in the translational substudy, seven patients on O and six patients on O + C. Patients on O + C had a greater decrease in IL-8 concentration and larger CEC fold increase compared with those on O alone (p = 0.026, p = 0.032). The fold increase in CEC on day 3 was associated with duration of progression-free survival (PFS) (R (2) = 0.77, 95% CI 0.55-0.97, p < 0.001). IL-8 post-pretreatment changes correlate with PFS (p = 0.028). XRCC1 DNA polymorphisms were not related to PFS. All patients had reduction in PAR incorporation, and all except one had reduction in vascular flow on DCE-MRI.

CONCLUSION

Our exploratory correlative studies indicate that CEC and IL-8 changes may be predictive for response to O + C and prognostic in recurrent platinum-sensitive OvCa, requiring prospective validation.

Deleterious BRCA1/2 mutation is an independent risk factor for carboplatin hypersensitivity reactions

Background:

We tested the hypothesis that BRCA1/2 mutation carriers with ovarian cancer are at higher risk of carboplatin hypersensitivity reactions (HSRs).

Methods:

Medical records of women enrolled in two carboplatin+olaparib clinical trials (NCT01237067/NCT01445418) were reviewed. A maximum of eight cycles containing carboplatin were administered.

Results:

All women (N=87) had good performance status and end-organ function. Incidences of carboplatin HSR before enrolment and on study were 17% and 21%, respectively. Most patients who developed carboplatin HSR had a deleterious BRCA1/2 mutation (93%) vs 50% in patients without HSR (P<0.0001). Multivariable analysis accounting for potential confounding variables including age, history of allergies, and cumulative prior carboplatin cycles confirmed deleterious BRCA1/2 mutation as an independent risk factor for carboplatin HSR (odds ratio 13.1 (95% confidence interval 2.6–65.4), P=0.0017). Mutation carriers had onset of carboplatin HSR at lower cumulative exposure (P=0.003). No significant difference in outcome was observed on our study between patients with and without a history of HSR.

Conclusion:

Deleterious BRCA1/2 mutation increased susceptibility and shortened time to carboplatin HSR, independently of other reported factors. These data suggest that at-risk women should be counselled regarding likelihood, symptoms, and potential earlier onset of carboplatin HSRs.

Abstract 35: Phase I study of dasatinib in combination with bevacizumab in advanced solid tumors (NCT01445509)

Background: Inhibition of the MAPK pathway with sorafenib and neutralization of VEGF with bevacizumab (B) resulted in clinical benefit with interactive toxicity. Dasatinib (D) is a broad spectrum tyrosine kinase inhibitor with high affinity for SRC family kinases. We hypothesized that using this upstream inhibitor of the MAPK pathway with B would maintain activity with less interactive toxicity.

Methods: A 3+3 dose escalation design incorporated with B 5mg/kg q2wk plus daily D 50, 70 and 100 mg in dose levels [DL] 1/2/3, then B 10mg/kg q 2wk plus D 100mg in DL4. DLT was defined during the first 6 weeks of treatment. Safety was assessed each 28d cycle and disease was reassessed every 2 cycles.

Results: 19 pts were treated in the dose escalation portion on 4 DLs. Pts (17F/2M) had a median age of 64 yrs (25-79), ECOG PS 0-1, and normal end-organ function. Most (14/19) pts had metastatic gynecologic cancers (6 endometrial/5 ovarian-peritoneal/2 cervix/1 rectovaginal GIST). Other cancers included breast (2), pancreatic neuroendocrine (1), medullary thyroid (1) and melanoma (1). Median number of prior treatments was 4 (1-11). The highest planned dose combination was examined without exceeding the MTD. No DLT was observed. Grade (g) 3 events included hypertension (2), pleural effusion (2), dyspnea (1) and pulmonary hypertension (1). D-mediated marrow suppression was observed in 12 pts: anemia (g1/2 [12 pts]), lymphopenia (g1/2 [9pts]; g3 [1pt]), thrombocytopenia (g1/2 [5pts]), and neutropenia (g1/2 [4pts]). Confirmed PR was seen in 1/17 evaluable pts, a pt with HER2+ breast cancer (5 mo). Stabilization &gt;/= 4 mo occurred in 9 pts (median 9 mo [4-18+mo]), yielding clinical benefit in 59%.

Conclusions: D 100 mg daily with B 10mg/kg q2wk appears to be active and is well-tolerated in pts with advanced solid tumors. G 3 adverse events were uncommon and g 4 events or severe marrow toxicities were not observed at the doses planned and examined. An expansion cohort is now accruing with functional imaging, tumor biopsies, and blood sampling for measurement of biochemical changes in SRC and VEGF signaling pathways.

Citation Format: Jung-Min Lee, Christina Annunziata, Anne M. Noonan, John L. Hays, Lori Minasian, Jo Anne Zujewski, Helen Chen, John Wright, Nicole Houston, Elise C. Kohn. Phase I study of dasatinib in combination with bevacizumab in advanced solid tumors (NCT01445509). [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 35. doi:10.1158/1538-7445.AM2013-35

A phase II clinical trial of polyethylene glycol-conjugated L-asparaginase in patients with advanced ovarian cancer: Early closure for safety

The anti-angiogenic activity of L-asparaginase (L-ASP) and the sensitivity of ovarian cancer cell lines to L-ASP has been previously demonstrated by preclinical findings. The aim of this clinical trial was to translate those findings and evaluate the activity of polyethylene glycol-conjugated L-asparaginase (PEG-ASP or pegaspargase) in advanced ovarian cancer. Women with recurrent ovarian cancer and good end-organ function were enrolled in an open-label phase II trial of PEG-ASP at a dose of 2,000 IU/m² by intravenous infusion every 2 weeks. Patients were evaluated for response every 8 weeks and for toxicity on an ongoing basis. Early stopping rules for toxicity and activity were included. Four patients were enrolled and received a total of 7 treatment cycles. The study ended accrual by invoking an early stopping rule, after excessive toxicity was identified in patients. Drug-related toxicities included grade 2 pancreatitis, fatigue, neutropenia, hypoalbuminemia, weight loss, dehydration, decreased fibrinogen and 1 case of grade 3 hypersensitivity reaction during cycle 2. One patient died during the study. No patients were evaluable for response. PEG-ASP was poorly tolerated in this group of advanced-stage ovarian cancer patients and no conclusions regarding activity may be drawn. Further studies of PEG-ASP in ovarian cancer patients are not recommended.

Feasibility and safety of sequential research-related tumor core biopsies in clinical trials

BACKGROUND

There has been increasing interest in serial research biopsies in studies of targeted therapies. Definition of patient characteristics and optimal target tissue for safe research tumor biopsy in the era of antiangiogenic and targeted agents is needed.

METHODS

This institutional review board-approved, retrospective study included chart and interventional radiology case review from 6 phase 1/2 studies at the National Cancer Institute.

RESULTS

One hundred forty-two of 150 protocol patients who were approached gave consent for research biopsies. Patients' median age was 56 years (range, 27-78 years), their median body mass index was 25.8 kg/m(2) (range, 14.4-46.2 kg/m(2) ), they had an Eastern Cooperative Oncology Group performance status of 0 or 1, and they had normal end-organ function. Baseline biopsies were collected from 138 of 142 patients (97%), and paired specimens were collected from 96 (70%). Most patients had metastatic gynecologic cancers (85%), and 78% had target disease below the diaphragm with a median size of 2.7 cm (range, 1-14.5 cm). Protocol therapies included kinase inhibitors (35%), angiogenesis inhibitors (54%), and olaparib/carboplatin (11%); therapy was not interrupted for biopsies. All adverse events were uncomplicated and were observed in 4 patients (liver subcapsular hematoma in 1 patient, vasovagal syncope in 2 patients, and pneumothorax in 1 patient). The complication rate in obese patients was similar to that in nonobese patients (3 of 108 patients vs 1 of 34 patients, respectively). Sixty-seven patients (48%) were receiving bevacizumab at the time of subsequent biopsies. The complication rate was not different between patients who were and were not receiving bevacizumab (3 of 67 patients vs 1 of 71 patients, respectively). Ninety-five percent of biopsies yielded useable material.

CONCLUSIONS

Serial percutaneous core-needle biopsies can be obtained safely and yield material applicable for multiple translational applications. Obesity and/or concomitant antiangiogenic therapy and depth of disease did not increase the risk or preclude the successful acquisition of useful tissue.

Abstract 1754: A pharmacokinetics/pharmacodynamics study of sequence specificity of the PARP inhibitor, olaparib (O) with carboplatin (C) in recurrent women's cancers NCT01237067

Background: C, O, and C+O have documented activity in BRCA1/2mut+ or BRCA-like breast and ovarian cancers (Br/OvCa). The effect of drug sequence on DNA damage and cell death is unknown. Our in vitro modeling suggests that exposure to O prior to C (O&gt;C) reduced double stranded DNA damage and cell loss. Our trial tests the hypothesis that C&gt;O causes more cellular injury. Methods: Eligible pts have recurrent women's cancers, good end organ function, and evaluable disease. A 3+3 dose escalation run-in defined the O tablet dose in combination with C (AUC 4). The study will now randomize pts to schedule A or B (below), allowing intra-pt and inter-cohort analysis of PK/PD endpoints. PBMCs will be collected C1/2 for measurement of platination and DNA damage/repair; DNA repair protein integrity will be assessed on archival tissues. Clinical benefit, response frequency and duration, and toxicity will be ascertained. Mutation carriers will undergo progression biopsy for analysis of BRCA1/2 re-expression mutations. Results: The phase I portion is complete. 12 women (8Ov/3Br/1Endometrial[En]) have been accrued on 3 dose levels (DLs). Median prior number of regimens was 5. No DLT have been seen in 5 evaluable pts on DL3 (O tablet 200mg q12h/C AUC4 [1 pt pending]). Gr3 AEs included neutropenia (44%), and gr2 were anemia (56%), fatigue (22 %), C hypersensitivity (22%), thrombocytopenia (11%), and nausea (11%). 1 pt (DL2; stable disease) died of unrelated bleeding during C4. Clinical benefit has been observed in 8 evaluable pts with PR in 2 BRCA1mut+ OvCa (9+, 11+ mo), stabilization &gt; 4mo in 6 pts (4OvCa,1BrCa, 1EnCa), and 3 are TETE. Conclusions: O in tablet formulation at 200mg q12h x 7d with C AUC4 q21d is active and tolerable, with observed interactive marrow suppression. Subsequent women will be randomized to examine schedule dependence of activity and toxicity.

Quality improvement within Independent Practitioner Associations: lessons from New Zealand

AIMS

To ascertain what quality improvement activities are being performed by associations of general practitioners (GPs) in New Zealand, to find out how they are supporting these activities, and learn about their experience of the process.

METHOD

A cross sectional questionnaire study of 25 independent practitioner associations (IPAs) in New Zealand.

RESULTS

All respondents (n=25) believed quality improvement was a responsibility of their organization, and for 48% it was their highest priority. All organizations carried out and supported a range of quality improvement activities. The major perceived barriers to quality improvement were negative attitudes and lack of time and money to support the process. Strategies to overcome these barriers included providing comparative data to staff in a peer group setting and providing financial incentives, management support and education.

CONCLUSIONS

Considerable quality improvement activity is occurring in primary care in New Zealand. A variety of barriers to the process and methods of overcoming them have been identified by some, but not all IPAs.

Changes in rest and exercise myocardial perfusion and left ventricular function 3 to 26 weeks after clinically uncomplicated acute myocardial infarction: effects of exercise training

The effects of exercise training on exercise myocardial perfusion and left ventricular (LV) function in the first 6 months after clinically uncomplicated acute myocardial infarction (AMI) were assessed in 53 consecutive men aged 55 +/- 9 years. Symptom-limited treadmill exercise with thallium myocardial perfusion scintigraphy and symptom-limited upright bicycle ergometry with equilibrium gated radionuclide ventriculography were performed 3, 11 and 26 weeks after AMI by 23 men randomized to training and 30 randomized to no training. Peak cycle capacity increased in both groups between 3 and 26 weeks (p less than 0.01), but reached higher levels in trained than in untrained patients (803 +/- 149 vs 648 +/- 182 kg-m/min, p less than 0.01). Reversible thallium perfusion defects were significantly more frequent at 3 than at 26 weeks: 59% and 36% of patients, respectively (p less than 0.05), without significant inter-group differences. Values of LV ejection fraction at rest, submaximal and peak exercise did not change significantly in either group. The increase in functional capacity, i.e., peak treadmill or bicycle workload, that occurred 3 to 26 weeks after infarction was significantly correlated with the increase in peak exercise heart rate (p less than 0.001), but not with changes in myocardial perfusion or LV function determined by radionuclide techniques. Changes in myocardial perfusion or LV function do not appear to account for the improvement in peak functional capacity that occurs within the first 6 months after clinically uncomplicated AMI.

Comparison of cardiovascular response to combined static-dynamic effort, postprandial dynamic effort and dynamic effort alone in patients with chronic ischemic heart disease

The cardiovascular responses to combined static-dynamic effort, postprandial dynamic effort and dynamic effort alone were evaluated by upright bicycle ergometry during equilibrium-gated blood pool scintigraphy in 24 men, mean age 59 +/- 8 years, with chronic ischemic heart disease. Combined static-dynamic effort and the postprandial state elicited a peak cardiovascular response similar to that of dynamic effort alone; work load 643 +/- 156 and 638 +/- 161 vs 650 +/- 153 kg-m/min, respectively; heart rate 147 +/- 14 and 145 +/- 14 vs 143 +/- 17 beats/min; systolic pressure 195 +/- 26 and 200 +/- 25 vs 197 +/- 25 mm Hg; and rate-pressure product 286 +/- 48 and 292 +/- 55 vs 282 +/- 52. Heart rate, intraarterial systolic and diastolic pressures, rate-pressure product and ejection fraction were similar for the three test conditions at the onset of ischemia and at peak effort. The prevalence and extent of exercise-induced ischemic left ventricular dysfunction, ST-segment depression, angina pectoris and ventricular ectopic activity were also similar during the three test conditions. Direct and indirect measurements of systolic and diastolic blood pressure were highly correlated. The onset of ischemic ST-segment depression and angina pectoris correlated as strongly with heart rate alone as with the rate-pressure product during all three test conditions. The cardiovascular response to combined static-dynamic effort and to postprandial dynamic effort becomes more similar to that of dynamic effort alone as dynamic effort reaches a symptom limit. If significant ischemic and arrhythmic abnormalities are absent during symptom-limited dynamic exercise testing, they are unlikely to appear during combined static-dynamic or postprandial dynamic effort. This simplifies, the task of formulating guidelines for physical effort in patients with chronic ischemic heart disease, especially in providing "clearance" to perform avocational and vocational tasks involving combined static-dynamic and postprandial dynamic effort.

The effect of a standardized psychological stressor on the cardiovascular response to physical effort soon after uncomplicated myocardial infarction

To determine whether a standardized psychological stressor combined with physical stress might disclose ischemic abnormalities not evident with physical stress alone, 30 men, mean age 54, were evaluated seven weeks after clinically uncomplicated myocardial infarction. In the first 20 patients, two symptom-limited treadmill tests (TM) were performed on the same day, with and without superimposed psychological quiz (Q). In the next 10 consecutive patients, the Q was administered at a submaximal level (4 METs). When TM and TM + Q responses were compared, no significant differences were noted in the maximal levels of heart rate (HR), systolic blood pressure (SBP), rate pressure product, or in the prevalence of ischemic ST segment depression or angina pectoris. The HR and double product at which ischemic ST segment depression and angina pectoris appeared were similar for the two types of testing. The psychological stress of a psychological quiz may not, of course, approximate the effect of the more severe stressors individuals may encounter in their daily routines.

A new method for evaluating antiarrhythmic drug efficacy

To develop standards for distinguishing antiarrhythmic drug effect from spontaneous variability of premature ventricular complexes (PVCs), 21 males (mean age 56 +/- 8 years) with chronic ischemic heart disease and PVCs underwent symptom-limited treadmill exercise testing and 24-hour ambulatory monitoring before and after 2 weeks of placebo medication. Linear regression analysis was used to describe the relationship between baseline and placebo PVC frequency for various indexes of ventricular ectopic activity and to establish 95% and 99% one-tailed confidence intervals for this relationship within the group of 21 patients. The lower limit of baseline PVC frequency for which the procedure could distinguish a placebo from a true drug response, termed the "sensitivity threshold," was an average frequency of 2.2 PVCs/hour for ambulatory electrocardiographic monitoring and 1.2 PVCs/min for treadmill exercise testing. All patients exceeded the sensitivity threshold on baseline ambulatory ECGs, but only 38% of patients did so on baseline treadmill exercise tests. To establish antiarrhythmic efficacy with 95% confidence, the minimal percent reduction of PVCs between baseline and placebo visits was 68% for treadmill exercise testing and 65% for ambulatory electrocardiography. Although these standards were developed in patients with chronic ischemic heart disease, the model can be used to establish antiarrhythmic drug efficacy in any patient group.

A comparison of static and dynamic exercise soon after myocardial infarction

The cardiovascular response to treadmill exercise testing and to isometric handgrip was compared in 20 selected patients three to five weeks after acute myocardial infarction. The heart rate and the heart rate-systolic blood pressure product were significantly higher during treadmill exercise than during two minutes of isometric handgrip sustained at 25% of maximum voluntary contraction. No significant difference in systolic blood pressure was noted between the two types of exercise while diastolic blood pressure was higher during isometric exercise. Asymptomatic ST-segment depression was noted in two patients during the the treadmill test and was absent during handgrip. Angina pectoris was not noted during either type of exercise. Ventricular ectopic activity was slightly more frequent during treadmill exercise. Isometric handgrip at 25% of maximum voluntary contraction may be performed safely soon after myocardial infarction and provides useful guidelines for performing many customary physical activities requiring upper extremity isometric exertion during early convalescence.

Comparison of cardiovascular responses to static-dynamic effort and dynamic effort alone in patients with chronic ischemic heart disease

Thirty men, mean age 55 years, known to have treadmill-induced ischemic ST-segment depression, performed static and dynamic effort, i.e., forearm lifting and treadmill exercise, separately and combined. Static effort was sustained at 20%, 25% or 30% of maximal forearm lifting capacity. Two symptom-limited treadmill tests, one with and one without added static effort, were performed on each of two visits. Compared with dynamic effort alone, combined static-dynamic effort decreased treadmill work load and increased heart rate, systolic blood pressure and rate-pressure product at the onset of ischemic ST-segment depression or angina pectoris: 7.1 +/- 0.4 vs 8.0 +/- 0.5 (SEM) multiples of resting oxygen consumption (mets), estimated; 141 +/- 3 vs 134 +/- 3 beats/min; 170 +/- 4 vs. 162 +/- 4 mm Hg and 239 +/- 8 vs 218 +/- 9 (p less than 0.001). The prevalence of angina pectoris was significantly less with combined static-dynamic effort than with dynamic effort alone. Static effort causes a resetting of the threshold at which ischemic abnormalities appear during dynamic effort.

Cardiovascular responses to dynamic and static effort soon after myocardial infarction. Application to occupational work assessment

Static and dynamic work involving the arms and the legs was performed by 40 men seven weeks after myocardial infarction. Leg ergometry produced a significantly higher peak work load, systolic blood pressure (BPs), heart rate (HR), and HR X BPs X 10(-2) product (DP) than did arm ergometry: 842 +/- 178 vs 546 +/- 135 kg-m/min, 176 +/- 24 vs 154 +/- 19 mm Hg and 256 +/- 54 vs 219 +/- 48 (SD). Peak heart rates were 145 and 142. Endpoints were primarily muscular and generalized fatigue and dyspnea. Ischemic abnormalities and ventricular ectopy were more frequent with leg ergometry. Sustained forearm lifting elicited higher HR, PBs and DP responses than sustained handgrip contraction: 95 +/- 16 vs 91 +/- 16 beats/min, 162 +/- 18 vs 152 +/- 17 mm Hg and 154 +/- 33 vs 139 +/- 33 (SD). Ischemic ST segment depression and significant ventricuar arrhythmias were infrequent with static effort. Dynamic leg testing is superior to dynamic or static arm testing in assessing the capacity of patients to perform physical work tasks after myocardial infarction.