Rebecca J. Benner

A Multicenter Study of Azithromycin, Alone and in Combination with Chloroquine, for the Treatment of Acute Uncomplicated Plasmodium falciparum Malaria in India

BACKGROUND Azithromycin has demonstrated in vitro and in vivo activity against Plasmodium falciparum, but small treatment studies have given mixed results. METHODS Participants with fever and with both a blood smear and a rapid diagnostic test positive for falciparum malaria were randomly assigned to groups that were treated with either azithromycin or chloroquine or to matched groups receiving a placebo. After an interim analysis, open-label combination therapy with both drugs was initiated. RESULTS At day 28, 5 (33%) of 15 participants in the azithromycin-treated group had remained free of fever, compared with 4 (27%) of 15 in the chloroquine-treated group. All subsequently enrolled participants then received combination therapy with azithromycin and chloroquine. In 61 (97%) of 67 participants, resolution of fever and parasitemia had occurred by day 7, and, through day 28, no clinical or parasitologic relapse had occurred in them. CONCLUSIONS Resolution of parasitemia was inadequate with monotherapy with either azithromycin or chloroquine, but combination therapy provided substantially improved clinical and parasitologic outcomes. The combination of azithromycin and chloroquine may be an effective alternative treatment for falciparum malaria and deserves further study.

Randomized, Phase III Trial of First-Line Figitumumab in Combination With Paclitaxel and Carboplatin Versus Paclitaxel and Carboplatin Alone in Patients With Advanced Non–Small-Cell Lung Cancer

PURPOSE Figitumumab (CP-751,871), a fully human immunoglobulin G2 monoclonal antibody, inhibits the insulin-like growth factor 1 receptor (IGF-1R). Our multicenter, randomized, phase III study compared figitumumab plus chemotherapy with chemotherapy alone as first-line treatment in patients with advanced non-small-cell lung cancer (NSCLC). PATIENTS AND METHODS Patients with stage IIIB/IV or recurrent NSCLC disease with nonadenocarcinoma histology received open-label figitumumab (20 mg/kg) plus paclitaxel (200 mg/m(2)) and carboplatin (area under the concentration-time curve, 6 mg · min/mL) or paclitaxel and carboplatin alone once every 3 weeks for up to six cycles. The primary end point was overall survival (OS). RESULTS Of 681 randomly assigned patients, 671 received treatment. The study was closed early by an independent Data Safety Monitoring Committee because of futility and an increased incidence of serious adverse events (SAEs) and treatment-related deaths with figitumumab. Median OS was 8.6 months for figitumumab plus chemotherapy and 9.8 months for chemotherapy alone (hazard ratio [HR], 1.18; 95% CI, 0.99 to 1.40; P = .06); median progression-free survival was 4.7 months (95% CI, 4.2 to 5.4) and 4.6 months (95% CI, 4.2 to 5.4), respectively (HR, 1.10; P = .27); the objective response rates were 33% and 35%, respectively. The respective rates of all-causality SAEs were 66% and 51%; P < .01). Treatment-related grade 5 adverse events were also more common with figitumumab (5% v 1%; P < .01). CONCLUSION Adding figitumumab to standard chemotherapy failed to increase OS in patients with advanced nonadenocarcinoma NSCLC. Further clinical development of figitumumab is not being pursued.

A phase III randomized study of gemcitabine and cisplatin with or without PF-3512676 (TLR9 agonist) as first-line treatment of advanced non-small-cell lung cancer

BACKGROUND This open-label phase III study assessed the addition of Toll-like receptor 9-activating oligodeoxynucleotide PF-3512676 to gemcitabine/cisplatin chemotherapy in patients with non-small-cell lung cancer (NSCLC). PATIENTS AND METHODS Chemotherapy-naive patients with stage IIIB or IV NSCLC were randomized (1:1) to receive six or fewer 3-week cycles of i.v. gemcitabine (1250 mg/m2 on days 1 and 8) and cisplatin alone (75 mg/m2 on day 1, control arm) or combined with s.c. PF-3512676 0.2 mg/kg on days 8 and 15 of each chemotherapy cycle and weekly thereafter until progression or unacceptable toxicity (experimental arm). No crossover was planned. The primary end point was overall survival (OS). RESULTS A total of 839 patients were randomized. Baseline demographics were well balanced. Median OS (11.0 versus 10.7 months; P = 0.98) and median progression-free survival (PFS) (both 5.1 months) were similar between groups. Grade ≥3 hematologic adverse events (AEs), injection-site reactions, and influenza-like symptoms were more frequently reported among patients receiving PF-3512676. At the first-interim analysis, the Data Safety Monitoring Committee recommended study discontinuation. Administration of PF-3512676 was halted based on efficacy futility and increased grade ≥3 AEs (experimental arm). CONCLUSIONS Addition of PF-3512676 to gemcitabine/cisplatin chemotherapy did not improve OS or PFS but did increase toxicity.BACKGROUND This open-label phase III study assessed the addition of Toll-like receptor 9-activating oligodeoxynucleotide PF-3512676 to gemcitabine/cisplatin chemotherapy in patients with non-small-cell lung cancer (NSCLC). PATIENTS AND METHODS Chemotherapy-naive patients with stage IIIB or IV NSCLC were randomized (1:1) to receive six or fewer 3-week cycles of i.v. gemcitabine (1250 mg/m2 on days 1 and 8) and cisplatin alone (75 mg/m2 on day 1, control arm) or combined with s.c. PF-3512676 0.2 mg/kg on days 8 and 15 of each chemotherapy cycle and weekly thereafter until progression or unacceptable toxicity (experimental arm). No crossover was planned. The primary end point was overall survival (OS). RESULTS A total of 839 patients were randomized. Baseline demographics were well balanced. Median OS (11.0 versus 10.7 months; P=0.98) and median progression-free survival (PFS) (both 5.1 months) were similar between groups. Grade≥3 hematologic adverse events (AEs), injection-site reactions, and influenza-like symptoms were more frequently reported among patients receiving PF-3512676. At the first-interim analysis, the Data Safety Monitoring Committee recommended study discontinuation. Administration of PF-3512676 was halted based on efficacy futility and increased grade≥3 AEs (experimental arm). CONCLUSIONS Addition of PF-3512676 to gemcitabine/cisplatin chemotherapy did not improve OS or PFS but did increase toxicity.

Randomized Phase III Trial of Paclitaxel/Carboplatin With or Without PF-3512676 (Toll-Like Receptor 9 Agonist) As First-Line Treatment for Advanced Non–Small-Cell Lung Cancer

PURPOSE This phase III study examined efficacy of the synthetic Toll-like receptor 9-activating oligodeoxynucleotide PF-3512676 in combination with standard paclitaxel/carboplatin chemotherapy in patients with advanced non-small-cell lung cancer (NSCLC). PATIENTS AND METHODS Chemotherapy-naive patients with stage IIIB or IV NSCLC were randomly assigned (1:1) to receive up to six courses of paclitaxel/carboplatin (intravenous paclitaxel 200 mg/m(2) and carboplatin at area under the [concentration-time] curve 6 on day 1 of a 3-week cycle) alone (control arm) or in combination with 0.2 mg/kg subcutaneous PF-3512676 on days 8 and 15 (investigational arm). Primary end point was overall survival (OS). RESULTS Baseline demographics were similar across arms (N = 828). Most patients (88%) had stage IV disease. Median OS and median progression-free survival (PFS) were similar (OS: investigational arm, 10.0 months v control arm, 9.8 months; P = .56; PFS: investigational arm, 4.8 months v control arm, 4.7 months; P = .79). Most commonly reported PF-3512676-related adverse events (AEs) were mild-to-moderate local injection site reactions, pyrexia, and flu-like symptoms. In the investigational arm, grades 3 to 4 AEs, including neutropenia, thrombocytopenia, and anemia, were more frequent, and more patients had one or more sepsis-related AEs versus controls (17 v 3). At first interim analysis, the Data Safety Monitoring Committee recommended study discontinuation because of lack of incremental efficacy and more sepsis-related serious AEs in the PF-3512676 arm. Administration of PF-3512676, but not chemotherapy, was halted. CONCLUSION Addition of PF-3512676 to paclitaxel/carboplatin did not improve OS or PFS versus paclitaxel/carboplatin alone for first-line treatment of patients with advanced NSCLC but did increase toxicity. This regimen cannot be recommended for treating patients with advanced NSCLC.

Randomized, phase III trial of figitumumab in combination with erlotinib versus erlotinib alone in patients with nonadenocarcinoma nonsmall-cell lung cancer

BACKGROUND Figitumumab (CP-751,871) is a fully human IgG2 monoclonal antibody that inhibits the insulin-like growth factor 1 receptor. This multicenter, randomized, phase III study investigated the efficacy of figitumumab plus erlotinib compared with erlotinib alone in patients with pretreated, nonsmall-cell lung cancer (NSCLC). PATIENTS AND METHODS Patients (stage IIIB/IV or recurrent disease with nonadenocarcinoma histology) who had previously received at least one platinum-based regimen were randomized to receive open-label figitumumab (20 mg/kg) plus erlotinib 150 mg/day or erlotinib alone every 3 weeks. The primary end point was overall survival (OS). RESULTS Of 583 patients randomized, 579 received treatment. The study was closed early by an independent data safety monitoring committee due to results crossing the prespecified futility boundary. At the final analysis, median OS was 5.7 months for figitumumab plus erlotinib and 6.2 months for erlotinib alone [hazard ratio (HR) 1.09; 95% confidence interval (CI) 0.91-1.31; P = 0.35]. Median progression-free survival was 2.1 months for figitumumab plus erlotinib and 2.6 months for erlotinib alone (HR 1.08; 95% CI 0.90-1.29; P = 0.43). Treatment-related nonfatal serious adverse events occurred in 18% and 5% of patients in the figitumumab arm or erlotinib alone arm, respectively. There were nine treatment-related deaths (three related to both drugs, four related to erlotinib alone and two related to figitumumab). CONCLUSIONS The addition of figitumumab to erlotinib did not improve OS in patients with advanced, pretreated, nonadenocarcinoma NSCLC. Clinical development of figitumumab has been discontinued. CLINICAL TRIAL ID NCT00673049.

Clinical Pharmacokinetics and Gastrointestinal Tolerability of a Novel Extended-Release Microsphere Formulation of Azithromycin

Background and objectiveA novel oral, extended-release, microsphere formulation of azithromycin (AZSR) was developed to improve the gastrointestinal tolerability profile while allowing administration of an entire treatment course of azithromycin in a single dose. Several phase I clinical pharmacology studies were conducted to (i) identify a well-tolerated single-dose formulation that met a predefined exposure target; and (ii) evaluate the effect of food and antacid on the absorption of this formulation. Of these, five pivotal studies are described here.MethodsThe pharmacokinetic profile of AZSR was compared with that of the commercially available immediate-release azithromycin formulation (AZM) in an open-label, crossover, single-dose study (Study A), and their gastrointestinal tolerability profiles were compared in an observer-blind, parallel group, single-dose study (Study B). The effects of food (a high-fat meal and a standard meal) and antacid (a single 20mL dose of Maalox® Regular Strength, containing magnesium hydroxide, aluminium hydroxide and simethicone) on the absorption of azithromycin from AZSR were evaluated in three separate open-label, crossover, single-dose studies (Studies C, D and E). Healthy adult subjects were enrolled in all five studies, and all subjects were evaluable for tolerability. The dose used for all azithromycin formulations was 2.0g. Serum azithromycin concentrations were determined using a validated high-performance liquid chromatography/electrochemical detection method, and pharmacokinetic parameters were analysed using noncompartmental methods.Results377 subjects received a single 2.0g dose of azithromycin as AZSR and/or AZM in the five studies. Compared with AZM, AZSR had a slower absorption rate (57% decrease in the mean peak concentration [Cmax] and an approximate 2.5-hour delay in the time to reach Cmax [tmax]), with a mean relative bioavailability of 82.8%, which met the predefined exposure target (at least 80% bioavailability relative to AZM). Compared with AZM, AZSR was associated with significantly lower rates of nausea and vomiting. A high-fat meal increased the mean area under the serum concentration-time curve [AUC] from time zero to 72 hours post-dose (AUC72h) by 23% and increased the Cmax of azithromycin by 115%. A standard meal increased the mean Cmax by 119% but had no clinically significant effect on the AUC72h. AZSR appeared to be better tolerated in the fasted state than in the fed state. The AUC72h and Cmax of AZSR were not significantly affected by co-administration with a single dose of antacid.ConclusionsThe extended-release microsphere formulation of azithromycin, AZSR, allows administration of an entire therapeutic course of azithromycin as a well-tolerated single 2.0g dose. This formulation should be administered on an empty stomach and can be co-administered with antacids.

Phase 2 trial of erlotinib with or without PF-3512676 (CPG 7909, a Toll-like receptor 9 agonist) in patients with advanced recurrent EGFR-positive non-small cell lung cancer

This phase 2 study assessed PF-3512676 plus erlotinib in patients with epidermal growth factor receptor-positive advanced non-small cell lung cancer after prior chemotherapy failure. Patients were randomized 1:1 to PF-3512676 (0.20 mg/kg injected subcutaneously once weekly) plus erlotinib (150 mg daily) or erlotinib alone. The primary objective was to estimate progression-free survival (PFS). Patients received PF-3512676 plus erlotinib (n = 18) or erlotinib alone (n = 21). The study was halted because an unplanned interim analysis indicated that large improvement in PFS with addition of PF-3512676 would be unlikely. In the PF-3512676-plus-erlotinib and erlotinib-alone arms, median PFS was 1.6 and 1.7 mo (hazard ratio, 1.00; 95% confidence interval, 0.5–2.0; P = 0.9335), respectively. Salient grade ≥ 3 adverse events in PF-3512676-plus-erlotinib and erlotinib-alone arms were diarrhea (5/0), dyspnea (5/6), fatigue (4/1), other flu-like symptoms (2/0), anemia (2/1), and lymphocytopenia (based on laboratory values, 1/4). Adding PF-3512676 to erlotinib did not show potential for increased progression-free survival over erlotinib alone in patients with advanced recurrent epidermal growth factor receptor-positive non-small cell lung cancer.

The WIZARD Trial as a Case Study of Flexible Clinical Trial Design

The design of a randomized, controlled, confirmatory efficacy clinical trial is influenced by multiple competing factors, including ethical, scientific, economic, and regulatory interests. Design elements, including choice of end points, study duration, and interim monitoring plans, need to be adapted to specific circumstances. The Weekly Intervention With Zithromax for Atherosclerosis and Its Related Disorders (WIZARD) study design was initially intended to meet the sponsors scientific goals while being subject to practical constraints. In response to changing circumstances, modifications to the study design were required. The WIZARD trial demonstrates the substantial flexibility in the design and conduct of group-sequential randomized trials not only during the design stage but also after the trial is under way, effectively satisfying evolving and competing demands while preserving the statistical and scientific validity of the study.

Gemtuzumab ozogamicin for de novo acute myeloid leukemia: final efficacy and safety updates from the open-label, phase 3 ALFA-0701 trial

The randomized, phase III ALFA-0701 trial showed that a reduced and fractionated dose of gemtuzumab ozogamicin added to standard front-line chemotherapy significantly improves event-free survival (EFS) in adults with de novo acute myeloid leukemia (AML). Here we report an independent review of EFS, final overall survival (OS), and additional safety results from ALFA-0701. Patients (n=271) aged 50-70 years with de novo AML were randomized to receive conventional front-line induction chemotherapy (3+7daunorubicin+cytarabine) with/without gemtuzumab ozogamicin 3 mg/m2 on days 1, 4, and 7 during induction. Patients in remission following induction therapy received 2 courses of consolidation therapy (daunorubicin+cytarabine) with/without gemtuzumab ozogamicin (3 mg/m2/day on day 1) according to their initial randomization. The primary end point was investigator-assessed EFS. Secondary end points included OS and safety. A blinded independent review confirmed the investigator-assessed EFS results [August 1, 2011; hazard ratio (HR) 0.66; 95% Confidence Interval (CI): 0.49–0.89; 2-sided P=0.006], corresponding to a 34% reduction in risk of events in the gemtuzumab ozogamicin versus control arm. Final OS at April 30, 2013 favored gemtuzumab ozogamicin but was not significant. No differences in early death rate were observed between arms. The main toxicity associated with gemtuzumab ozogamicin was prolonged thrombocytopenia. Veno-occlusive disease (including after transplant) was observed in 6 patients in the gemtuzumab ozogamicin arm and 2 in the control arm. In conclusion, gemtuzumab ozogamicin added to standard intensive chemotherapy has a favorable benefit/risk ratio. These results expand front-line treatment options for adult patients with previously untreated AML. (Trial registered at clinicaltrials.gov; identifier: 00927498.)