Stereotactic body radiotherapy with or without selective dismutase mimetic in pancreatic adenocarcinoma: an adaptive, randomised, double-blind, placebo-controlled, phase 1b/2 trial.

BACKGROUND: Stereotactic body radiotherapy (SBRT) has the potential to ablate localised pancreatic ductal adenocarcinoma. Selective dismutase mimetics sensitise tumours while reducing normal tissue toxicity. This trial was designed to establish the efficacy and toxicity afforded by the selective dismutase mimetic avasopasem manganese when combined with ablative SBRT for localised pancreatic ductal adenocarcinoma. METHODS: In this adaptive, randomised, double-blind, placebo-controlled, phase 1b/2 trial, patients aged 18 years or older with borderline resectable or locally advanced pancreatic cancer who had received at least 3 months of chemotherapy and had an Eastern Cooperative Oncology Group performance status of 0-2 were enrolled at six academic sites in the USA. Eligible patients were randomly assigned (1:1), with block randomisation (block sizes of 6-12) with a maximum of 24 patients per group, to receive daily avasopasem (90 mg) or placebo intravenously directly before (ie, within 180 min) SBRT (50, 55, or 60 Gy in five fractions, adaptively assigned in real time by Bayesian estimates of 90-day safety and efficacy). Patients and physicians were masked to treatment group allocation, but not to SBRT dose. The primary objective was to find the optimal dose of SBRT with avasopasem or placebo as determined by the late onset EffTox method. All analyses were done on an intention-to-treat basis. This study is registered with ClinicalTrials.gov, NCT03340974, and is complete. FINDINGS: Between Jan 25, 2018, and April 29, 2020, 47 patients were screened, of whom 42 were enrolled (median age was 71 years [IQR 63-75], 23 [55%] were male, 19 [45%] were female, 37 [88%] were White, three [7%] were Black, and one [2%] each were unknown or other races) and randomly assigned to avasopasem (n=24) or placebo (n=18); the placebo group was terminated early after failing to meet prespecified efficacy parameters. At data cutoff (June 28, 2021), the avasopasem group satisfied boundaries for both efficacy and toxicity. Late onset EffTox efficacy response was observed in 16 (89%) of 18 patients at 50 Gy and six (100%) of six patients at 55 Gy in the avasopasem group, and was observed in three (50%) of six patients at 50 Gy and nine (75%) of 12 patients at 55 Gy in the placebo group, and the Bayesian model recommended 50 Gy or 55 Gy in five fractions with avasopasem for further study. Serious adverse events of any cause were reported in three (17%) of 18 patients in the placebo group and six (25%) of 24 in the avasopasem group. In the placebo group, grade 3 adverse events within 90 days of SBRT were abdominal pain, acute cholangitis, pyrexia, increased blood lactic acid, and increased lipase (one [6%] each); no grade 4 events occurred. In the avasopasem group, grade 3-4 adverse events within 90 days of SBRT were acute kidney injury, increased blood alkaline phosphatase, haematoma, colitis, gastric obstruction, lung infection, abdominal abscess, post-surgical atrial fibrillation, and pneumonia leading to respiratory failure (one [4%] each).There were no treatment-related deaths but one late death in the avasopasem group due to sepsis in the setting of duodenal obstruction after off-study treatment was reported as potentially related to SBRT. INTERPRETATION: SBRT that uses 50 or 55 Gy in five fractions can be considered for patients with localised pancreatic ductal adenocarcinoma. The addition of avasopasem might further enhance disease outcomes. A larger phase 2 trial (GRECO-2, NCT04698915) is underway to validate these results. FUNDING: Galera Therapeutics.

Two-Year Tumor Outcomes of a Phase 2B, Randomized, Double-Blind Trial of Avasopasem Manganese (GC4419) Versus Placebo to Reduce Severe Oral Mucositis Owing to Concurrent Radiation Therapy and Cisplatin for Head and Neck Cancer.

PURPOSE: Avasopasem manganese (GC4419), an investigational selective dismutase mimetic radioprotector, reduced duration, incidence, and severity of severe oral mucositis (World Health Organization grade 3-4) in a phase 2b, randomized, double-blind trial of patients receiving concurrent cisplatin (cis) and radiation therapy (RT) for head and neck cancer. We report the secondary endpoints of final 1- and 2-year tumor outcomes and exploratory data on trismus and xerostomia. METHODS AND MATERIALS: Patients with locally advanced oral cavity or oropharynx cancer to be treated with definitive or postop cis and RT were randomized to 1 of 3 arms: 30 mg avasopasem, 90 mg avasopasem, or placebo. Pairwise comparisons of Kaplan-Meier estimates (each active arm separately vs placebo) were made for overall survival, progression-free survival, locoregional control, and distant metastasis-free survival. Xerostomia and trismus data were collected at each follow-up visit and analyzed for trends by post-RT timepoint and treatment group. RESULTS: At a median follow-up for the entire cohort of 25.5 months (25th-75th percentile, 24.6-26.2 months; range, 0.2-31.9 months), Kaplan-Meier estimates of 1- and 2-year overall survival, progression-free survival, locoregional control, and distant metastasis-free survival were not statistically different. No trends were apparent in xerostomia or trismus data. CONCLUSIONS: Avasopasem does not lead to statistically different tumor control outcomes when used concurrently with cis and RT for head and neck cancer. There was no detectable effect on trismus or xerostomia.

Mitochondrial Superoxide Dismutase in Cisplatin-Induced Kidney Injury.

Cisplatin is a chemotherapy agent commonly used to treat a wide variety of cancers. Despite the potential for both severe acute and chronic side effects, it remains a preferred therapeutic option for many malignancies due to its potent anti-tumor activity. Common cisplatin-associated side-effects include acute kidney injury (AKI) and chronic kidney disease (CKD). These renal injuries may cause delays and potentially cessation of cisplatin therapy and have long-term effects on renal function reserve. Thus, developing mechanism-based interventional strategies that minimize cisplatin-associated kidney injury without reducing efficacy would be of great benefit. In addition to its action of cross-linking DNA, cisplatin has been shown to affect mitochondrial metabolism, resulting in mitochondrially derived reactive oxygen species (ROS). Increased ROS formation in renal proximal convoluted tubule cells is associated with cisplatin-induced AKI and CKD. We review the mechanisms by which cisplatin may induce AKI and CKD and discuss the potential of mitochondrial superoxide dismutase mimetics to prevent platinum-associated nephrotoxicity.

Phase IIb, Randomized, Double-Blind Trial of GC4419 Versus Placebo to Reduce Severe Oral Mucositis Due to Concurrent Radiotherapy and Cisplatin For Head and Neck Cancer.

PURPOSE: Oral mucositis (OM) remains a common, debilitating toxicity of radiation therapy (RT) for head and neck cancer. The goal of this phase IIb, multi-institutional, randomized, double-blind trial was to compare the efficacy and safety of GC4419, a superoxide dismutase mimetic, with placebo to reduce the duration, incidence, and severity of severe OM (SOM). PATIENTS AND METHODS: A total of 223 patients (from 44 institutions) with locally advanced oral cavity or oropharynx cancer planned to be treated with definitive or postoperative intensity-modulated RT (IMRT; 60 to 72 Gy [≥ 50 Gy to two or more oral sites]) plus cisplatin (weekly or every 3 weeks) were randomly assigned to receive 30 mg (n = 73) or 90 mg (n = 76) of GC4419 or to receive placebo (n = 74) by 60-minute intravenous administration before each IMRT fraction. WHO grade of OM was assessed biweekly during IMRT and then weekly for up to 8 weeks after IMRT. The primary endpoint was duration of SOM tested for each active dose level versus placebo (intent-to-treat population, two-sided α of .05). The National Cancer Institute Common Terminology Criteria for Adverse Events, version 4.03, was used for adverse event grading. RESULTS: Baseline patient and tumor characteristics as well as treatment delivery were balanced. With 90 mg GC4419 versus placebo, SOM duration was significantly reduced (P = .024; median, 1.5 v 19 days). SOM incidence (43% v 65%; P = .009) and severity (grade 4 incidence, 16% v 30%; P = .045) also were improved. Intermediate improvements were seen with the 30-mg dose. Safety was comparable across arms, with no significant GC4419-specific toxicity nor increase of known toxicities of IMRT plus cisplatin. The 2-year follow-up for tumor outcomes is ongoing. CONCLUSION: GC4419 at a dose of 90 mg produced a significant, clinically meaningful reduction of SOM duration, incidence, and severity with acceptable safety. A phase III trial (ROMAN; ClinicalTrials.gov identifier: NCT03689712) has begun.

Phase 1b/2a Trial of the Superoxide Dismutase Mimetic GC4419 to Reduce Chemoradiotherapy-Induced Oral Mucositis in Patients With Oral Cavity or Oropharyngeal Carcinoma.

PURPOSE: To assess the safety of the superoxide dismutase mimetic GC4419 in combination with radiation and concurrent cisplatin for patients with oral cavity or oropharyngeal cancer (OCC) and to assess the potential of GC4419 to reduce severe oral mucositis (OM). PATIENTS AND METHODS: Patients with locally advanced OCC treated with definitive or postoperative intensity modulated radiation therapy (IMRT) plus cisplatin received GC4419 by 60-minute intravenous infusion, ending <60 minutes before IMRT, Monday through Friday for 3 to 7 weeks, in a dose and duration escalation study. Oral mucositis was assessed twice weekly during and weekly after IMRT. RESULTS: A total of 46 patients received GC4419 in 11 separate dosing and duration cohorts: dose escalation occurred in 5 cohorts receiving 15 to 112 mg/d over 3 weeks (n=20), duration escalation in 3 cohorts receiving 112 mg/d over 4 to 6 weeks (n=12), and then 3 additional cohorts receiving 30 or 90 mg/d over 6 to 7 weeks (n=14). A maximum tolerated dose was not reached. One dose-limiting toxicity (grade 3 gastroenteritis and vomiting with hyponatremia) occurred in each of 2 separate cohorts at 112 mg. Nausea/vomiting and facial paresthesia during infusion seemed to be GC4419 dose-related. Severe OM occurred through 60 Gy in 4 of 14 patients (29%) dosed for 6 to 7 weeks, with median duration of only 2.5 days. CONCLUSIONS: The safety of GC4419 concurrently with chemoradiation for OCC was acceptable. Toxicities included nausea/vomiting and paresthesia. Doses of 30 and 90 mg/d administered for 7 weeks were selected for further study. In an exploratory analysis, severe OM seemed less frequent and briefer than expected.

Double-blind, placebo-controlled, randomized phase 2 study of the proapoptotic agent AT-101 plus docetaxel, in second-line non-small cell lung cancer.

BACKGROUND: AT-101 is an inhibitor of Bcl-2 family proteins including Bcl-2, Bcl-xL, Mcl-1, and Bcl-w. In vivo and in vitro studies have exhibited broad activity of AT-101, including synergy with docetaxel in non-small cell lung cancer tumor models. METHODS: We conducted a prospective, randomized (1:1), double-blind, placebo-controlled phase 2 study. Eligible patients must have received one prior chemotherapeutic regimen for advanced or metastatic non-small cell lung cancer and may also have received therapy with an epidermal growth factor receptor inhibitor. Patients received AT-101 (40 mg b.i.d. × 3 days) or placebo in combination with docetaxel (75 mg/m on day 1) every 21 days. The primary endpoint was progression-free survival (PFS) as determined by independent review; other endpoints include overall survival and PFS by investigator determination. Approximately 102 patients were planned to provide 70 events (80% power, hazard ratio [HR] of 0.6, one-sided alpha of 0.1). RESULTS: : One hundred six patients were assigned to treatment and 105 patients received at least one dose of AT-101 or placebo. Baseline factors were balanced between treatment groups: median age 59 years; 77% men, and 79% current or former smokers. Ninety-three percent of patients had distant metastatic disease at randomization and 56% squamous histology. The most frequently reported adverse events were fatigue (18%), anemia (18%), and dyspnea (18%). No statistically significant differences in serious adverse events were observed between AT-101 and placebo; grade 1/2 headaches appeared more frequently with AT-101 (9% versus 0%) and neutropenia was reported more frequently in the docetaxel plus placebo arm compared with docetaxel plus AT-101 (17% versus 8%). Unlike trials with continuous daily dosing of AT-101, no cases of small bowel obstruction were reported. The response rate and median PFS were not different between the arms by independent review, PFS 7.5 weeks for docetaxel plus AT-101 and 7.1 weeks for docetaxel plus placebo arms (HR, 1.04; p = 0.57). The median overall survival was 7.8 months for docetaxel plus AT-101 versus 5.9 months for docetaxel plus placebo (HR, 0.82; p = 0.21). CONCLUSIONS: The primary endpoint of improved PFS for AT-101 plus docetaxel was not met. AT-101 plus docetaxel was well tolerated with an adverse event profile indistinguishable from the base docetaxel regimen. AT-101 is the first oral, pan Bcl-2 family inhibitor to exhibit a possible survival benefit in a randomized study.

Targeting Bcl-2 family members with the BH3 mimetic AT-101 markedly enhances the therapeutic effects of chemotherapeutic agents in in vitro and in vivo models of B-cell lymphoma.

Overexpression of antiapoptotic members of the Bcl-2 family are observed in approximately 80% of B-cell lymphomas, contributing to intrinsic and acquired drug resistance. Nullifying antiapoptotic function can potentially overcome this in-trinsic and acquired drug resistance. AT-101 is a BH3 mimetic known to be a potent inhibitor of antiapoptotic Bcl-2 family members including Bcl-2, Bcl-X(L), and Mcl-1. In vitro, AT-101 exhibits concentration- and time-dependent cytotoxicity against lymphoma and multiple myeloma cell lines, enhancing the activity of cytotoxic agents. The IC(50) for AT-101 is between 1 and 10 microM for a diverse panel of B-cell lymphomas. AT-101 was synergistic with carfilzomib (C), etoposide (E), doxorubicin (D), and 4-hydroxycyclophosphamide (4-HC) in mantle cell lymphoma (MCL) lines. In a transformed large B-cell lymphoma line (RL), AT-101 was synergistic when sequentially combined with 4-HC, but not when both drugs were added simultaneously. AT-101 also induced potent mitochondrial membrane depolarization (Delta Psi m) and apoptosis when combined with carfilzomib, but not with bortezomib in MCL. In severe combined immunodeficient (SCID) beige mouse models of drug-resistant B-cell lymphoma, 35 mg/kg per day of AT-101 was safe and efficacious. The addition of AT-101 to cyclophosphamide (Cy) and rituximab (R) in a schedule-dependent manner enhanced the efficacy of the conventional therapy.

A phase I trial of aprinocarsen (ISIS 3521/LY900003), an antisense inhibitor of protein kinase C-alpha administered as a 24-hour weekly infusion schedule in patients with advanced cancer.

PURPOSE: A phase I study was performed to determine the maximum tolerated dose (MTD), safety profile and pharmacology of aprinocarsen (ISIS 3521), an antisense oligonucleotide to protein kinase C-alpha, in patients with refractory solid tumors. EXPERIMENTAL DESIGN: Fourteen patients were treated in sequential cohorts of aprinocarsen by 24-hour continuous infusion (CIV), weekly, at doses of 6, 12, 18 and 24 mg/kg. RESULTS: One grade 4 toxicity was observed, transient grade 4 neutropenia at 18 mg/kg. Grade 3 toxicities included neutropenia at 12 mg/kg, fever and hemorrhage at 18 mg/kg, and neutropenia, nausea, and chills at 24 mg/kg. Grade 2 toxicities included thrombocytopenia myalgias, chills, headache, fatigue, fever and nausea/vomiting. Mean prothrombin times and activated partial thromboplastin times (aPTT) increased by 10% and 29% from baseline (p = 0.006 and 0.005). Mean complement split products (Bb and C3a) increased 1.6-fold and 3.6-fold (from p = 0.014 and 0.004, respectively). These changes correlated with dose and were transient with recovery to baseline by day 7. Steady state plasma concentrations (Css) of aprinocarsen were achieved within four hours. Css better described changes in aPTT than dose. Clinical evidence of complement activation was not observed. CONCLUSIONS: In contrast to 21-day protracted infusion schedules, delivery of aprinocarsen over a 24-hour infusion schedule showed concentration-dependent effects on coagulation and complement, which are consistent with nonclinical toxicology studies performed in the phosphorothioate DNA antisense drug class. These coagulation and complement changes resulted in a maximum tolerated dose 24 mg/kg.

Efficacy and toxicity of the antisense oligonucleotide aprinocarsen directed against protein kinase C-alpha delivered as a 21-day continuous intravenous infusion in patients with recurrent high-grade astrocytomas.

Protein kinase C alpha (PKC-alpha) is a cytoplasmic serine threonine kinase involved in regulating cell differentiation and proliferation. Aprinocarsen is an antisense oligonucleotide against PKC-alpha that reduces PKC-alphain human cell lines and inhibits a human glioblastoma tumor cell line in athymic mice. In this phase 2 study, aprinocarsen was administered to patients with recurrent high-grade gliomas by continuous intravenous infusion (2.0 mg/kg/day for 21 days per month). Twenty-one patients entered this trial. Their median age was 46 years (range, 28-68 years), median Karnofsky performance status was 80 (range, 60-100), median tumor volume was 58 cm3 (range, 16-254 cm3), and histology included glioblastoma multiforme (n = 16), anaplastic oligodendroglioma (n = 4), and anaplastic astrocytoma (n = 1). The number of prior chemotherapy regimens included none (n = 3), one (n = 10), and two (n = 8). No tumor responses were observed. Patients on this therapy rapidly developed symptoms of increased intracranial pressure with increased edema, enhancement, and mass effect on neuroimaging. The median time to progression was 36 days, and median survival was 3.4 months. The observed toxicities were mild, reversible, and uncommon (grade 3 thrombocytopenia [n = 3] and grade 4 AST [n = 1]), and no coagulopathy or CNS bleeding resulted from this therapy. Plasma concentrations of aprinocarsen during the infusion exhibited significant interpatient variability (mean = 1.06 mug/ml; range, 0.34-6.08 mug/ml). This is the first study to use an antisense oligonucleotide or a specific PKC-alpha inhibitor in patients with high-grade gliomas. No clinical benefit was seen. The rapid deterioration seen in these patients could result from tumor growth or an effect of aprinocarsen on bloodbrain barrier integrity.

A phase II trial of ISIS 3521 in patients with metastatic colorectal cancer.

This phase II study was designed to characterize the clinical activity of ISIS 3521 in patients with metastatic colorectal cancer (CRC). Sixteen patients with pretreated or refractory CRC were treated with ISIS 3521. Eleven patients were given a dose of 2.0 mg/kg per day, and 5 patients received 3.0 mg/kg per day given over 21 days followed by a 7-day rest period. Patients continued with study until evidence of disease progression or unacceptable toxicity was detected. Patients underwent baseline tumor biopsies followed by a second biopsy during the last week of the first 21-day infusion. All 16 patients underwent baseline tumor biopsies, and 12 of the 16 patients underwent on-study tumor biopsies. No evidence of tumor response was observed. One patient had stable disease after 2 cycles and remained on for 1 additional cycle only to demonstrate progression of disease at that time. No dose-limiting or other significant toxicities were observed at both dosages, which could not be explained by progression of disease. Fatigue was common in all patients treated but was not dose limiting, and there was no evidence of coagulopathy. Analysis of the tumor biopsies obtained from the 11 evaluable samples showed marked uptake of ISIS 3521 in the normal liver parenchyma. However, there was minimal uptake within the tumor cells. In addition, no evidence of any alteration in protein kinase C-a within the tumors or any downstream effects leading to apoptosis were observed. ISIS 3521 demonstrated no clinical activity or target modulation in refractory metastatic CRC.

A phase I/II study of LY900003, an antisense inhibitor of protein kinase C-alpha, in combination with cisplatin and gemcitabine in patients with advanced non-small cell lung cancer.

PURPOSE: Protein kinase C-alpha has been implicated in malignant transformation and proliferation. Based on in vivo superadditive interaction between the protein kinase C-alpha antisense oligonucleotide LY900003 (Affinitak, ISIS 3521) and cisplatin, we designed this phase I/II trial of LY900003 with cisplatin/gemcitabine. EXPERIMENTAL DESIGN: The safety of the combination, as well as potential pharmacokinetic interactions, was evaluated in the phase I portion of the trial. The phase II portion evaluated the antitumor activity of the combination in previously untreated patients with stage IIIB/IV non-small-cell lung cancer (NSCLC). RESULTS: Seven patients received 18 cycles of the combination during the phase I portion. Dose-limiting toxicity was only observed in one of six evaluable patients (grade 3 fatigue). However, due to a relatively high frequency of thrombocytopenia, cisplatin 80 (mg/m2) and gemcitabine (1,000 mg/m2) were recommended for the phase II portion. Antitumor activity was observed in two patients (one with NSCLC and one with pancreatic carcinoma), and prolonged stabilization was observed in two others. No pharmacokinetic interactions occurred. In the phase II portion, 55 NSCLC patients received the combination at two gemcitabine doses [1,000 mg/m2, n=44 (original cohort); 1,250 mg/m2, n=11 (expanded cohort)]. Fourteen of 39 evaluable patients in the original cohort had a response rate (1 complete response and 13 partial responses; response, 36%), whereas 2 of 9 evaluable patients in the expanded cohort experienced partial response (combined response rate, 33%). The median time to treatment failure was 3.9 months, whereas the median time response to progression for the 48 patients with evaluable response was 4.4 months (confidence interval, 3.5-5.5 months). Intent to treat median survival time was 8.9 months. Forty-eight percent of the patients experienced catheter-related events. CONCLUSIONS: LY900003 can be administered safely in combination with cisplatin and gemcitabine and is associated with antitumor activity in patients with advanced NSCLC. Better characterization of subsets of patients most likely to benefit from this combination therapy is needed.

A Phase II trial of aprinocarsen, an antisense oligonucleotide inhibitor of protein kinase C alpha, administered as a 21-day infusion to patients with advanced ovarian carcinoma.

BACKGROUND: It has been postulated that protein kinase C alpha (PKC-alpha) plays a pivotal role in signal transduction in tumor cancer cells. Aprinocarsen, a 20-base antisense oligonucleotide, has shown ability to inhibit PKC-alpha protein expression and inhibit tumor growth in human xenograft models. In a previous Phase I trial, the authors demonstrated the safety and some evidence of activity in ovarian carcinoma of aprinocarsen administered as a 21-day, continuous, intravenous infusion. METHODS: In this Phase II trial, 36 patients with advanced ovarian carcinoma were treated with aprinocarsen at a dose of 2 mg/kg per day delivered as a 21-day, continuous, intravenous infusion. The primary objective was to determine the antitumor response, and the secondary objectives were to evaluate toxicity and to evaluate effects on quality of life (QOL). RESULTS: Between September 1997 and December 1999, 36 patients (median age, 58 years) were enrolled in this trial. Patients were stratified into 2 groups: a platinum-sensitive group (n = 12 patients) and a platinum-resistant group (n = 24 patients). All 36 patients were evaluable for toxicity, and 27 patients were fully assessable for antitumor response after 2 cycles of therapy. All patients had received prior treatments. No objective responses were noted in the platinum-sensitive group. In the platinum-resistant group, 1 patient had some evidence of antitumor activity indicated by a decrease in serum CA 125 and stable disease on imaging studies for 8 months. No changes were noted in overall patient ratings for any of the five QOL domains. CONCLUSIONS: When it was administered as a single agent, aprinocarsen did not have significant clinical activity in patients with advanced ovarian carcinoma. Further study may be warranted in combination with platinum-based regimens.

A phase I trial of ISIS 2503, an antisense inhibitor of H-ras, in combination with gemcitabine in patients with advanced cancer.

PURPOSE: The purpose of this study was to define the toxicity, pharmacokinetics, and clinical activity of the combination of ISIS 2503, an oligodeoxynucleotide antisense inhibitor of H-ras, and gemcitabine in patients with advanced solid tumors. EXPERIMENTAL DESIGN: The target dose of ISIS 2503 on this study was 6 mg/kg/day. Twenty-seven patients (16 male, 11 female) received 97 treatment courses (median, 2; range, 1-13). Nineteen patients were treated with a fixed gemcitabine dose of 1000 mg/m(2) on days 1 and 8 and two escalating doses of ISIS 2503 (4 and 6 mg/kg/day) as a 14-day continuous infusion starting on day 1. In addition, 8 patients (5 male, 3 female) received a flat dose of ISIS 2503 based on ideal body weight. Cycles were repeated every 3 weeks. Toxicities, graded according to the National Cancer Institute Common Toxicity Criteria, were recorded as maximum grade/patient for all treatment cycles. Pharmacokinetic analyses were performed to evaluate any interaction between these two agents. RESULTS: The most common nondose-limiting toxicity was hematological, manifested as neutropenia (5 grade 2, 7 grade 3, and 1 grade 4) and thrombocytopenia (10 grade 1, 5 grade 2, 5 grade 3, and 1 grade 4). Nonhematological toxicities included anorexia (7 grade 1, 3 grade 2, and 1 grade 3), nausea (10 grade 1 and 1 grade 3), fatigue (6 grade 1, 5 grade 2, and 3 grade 3), fever (6 grade 1, 2 grade 2, 1 and grade 3), and thrombosis associated with central lines (5). The plasma concentration of gemcitabine at the end of infusion was altered in the presence of ISIS 2503, leading to alterations on other pharmacokinetic parameters, but the observed differences were not clinically relevant. The plasma disposition of ISIS 2503 was not altered by gemcitabine coadministration. One partial response was documented in a heavily pretreated patient with metastatic breast cancer. Disease stabilization for greater than six cycles of treatment was observed in 5 patients. CONCLUSIONS: The combination of gemcitabine and ISIS 2503 was well tolerated and clinically active in this group of heavily pretreated patients. The recommended Phase II dose of gemcitabine (1000 mg/m(2)) and ISIS 2503 (6 mg/kg/day) warrants additional evaluation.

Applying antisense technology: Affinitak and other antisense oligonucleotides in clinical development.

Progress in the development of antisense drugs over the last decade has led to the approval of the first such drug--Vitravene for AIDS-related CMV retinitis--and the development of a large number of antisense drugs in clinical trials. Antisense drugs are now being studied in Phase 3 trials for patients with cancer and inflammatory bowel disease. Other antisense drugs are in development for rheumatoid arthritis, other inflammatory conditions, and hepatitis C. Still other antisense drugs are entering clinical trials for treatment of metabolic conditions such as diabetes and hyperlipidemia. These latter applications provide the potential for target effects to be more directly measured in the clinic. Improved antisense chemistry, which will enhance the feasibility of subcutaneous and oral administration of antisense drugs and offer the potential of less frequent dosing, is expected to further expand the opportunities for antisense drug development.

Phase I clinical and pharmacokinetic study of protein kinase C-alpha antisense oligonucleotide ISIS 3521 administered in combination with 5-fluorouracil and leucovorin in patients with advanced cancer.

The present study was designed to determine the maximum tolerated dose (MTD), toxicity profile, pharmacokinetics (PKs), and antitumor activity of the protein kinase C-alpha antisense oligonucleotide ISIS 3521 (ISIS Pharmaceuticals, Inc., Carlsbad, CA) when administered in combination with 5-fluorouracil (5-FU) and leucovorin (LV). Patients with refractory solid tumors received ISIS 3521 as a 21-day continuous infusion administered simultaneously with 5-FU and LV given daily for 5 days repeated every 4-5 weeks (one cycle). 5-FU and ISIS 3521 PK analysis were performed on samples taken during the first cycle in all patients. Fifteen patients received ISIS 3521 at one of three dose levels: (a) 1.0 (n = 3 patients); (b) 1.5 (n = 3 patients); and (c) 2.0 (n = 9 patients) mg/kg/day. All patients simultaneously received 5-FU (425 mg/m(2)/day) and LV (20 mg/m(2)/day) for 5 consecutive days. Grade 1-2 toxicities included alopecia, fatigue, mucositis, diarrhea, anorexia, nausea/vomiting, and tumor pain. One patient had grade 3 chest pain considered to be related to 5-FU therapy, another patient had dose-limiting grade 3 mucositis resolving in <7 days, and one patient with a history of gastritis had an acute upper gastrointestinal bleed thought to be 5-FU-induced toxicity. Five patients developed cycle 1 grade 4 neutropenia, which resolved without colony-stimulating factors before the next treatment cycle. There were no effects on prothrombin time and activated partial thromboplastin time. A clinically defined MTD was not reached. The character and severity of these toxicities do not seem to be dose related, and, as such, there was no classical dose-limiting toxicity defining the MTD. ISIS 3521 PKs in the presence of 5-FU was consistent with those reported previously. 5-FU PK parameters were also similar in the presence or absence of ISIS 3521. Six of 14 patients ( approximately 43%) across all dose cohorts had an improvement in measurable tumor response ranging from minor reduction in tumor size (4 patients) to objective partial response (>50% reduction in tumor size, 2 patients). ISIS 3521 is tolerable at its recommended single-agent dose when given with 5-FU and LV. There is no apparent PK interaction between ISIS 3521 and 5-FU and LV. Antitumor activity was observed with the combination; however, it is uncertain whether clinical activity is a result of enhanced drug interaction. Our study warrants further exploration of efficacy in a Phase II and/or Phase III clinical trial setting.