Shariq Haider

Phase 1b Study of New Posaconazole Tablet for Prevention of Invasive Fungal Infections in High-Risk Patients with Neutropenia

ABSTRACT Posaconazole tablets, a new oral formulation of posaconazole, can be effective when given as antifungal prophylaxis to neutropenic patients at high risk for invasive fungal infection (e.g., those with acute myelogenous leukemia or myelodysplastic syndrome). Such effectiveness might be specifically important to patients with poor oral intake because of nausea, vomiting, or chemotherapy-associated mucositis. This was a prospective, global study in high-risk patients to characterize the pharmacokinetics and safety profile of posaconazole tablets and to identify the dose of posaconazole tablets that would provide exposure within a predefined range of exposures (steady-state average concentration [area under the concentration-time curve/24 h] of ≥500 ng/ml and ≤2,500 ng/ml in >90% of patients). The study evaluated two sequential dosing cohorts: 200 mg posaconazole once daily (n = 20) and 300 mg posaconazole once daily (n = 34) (both cohorts had a twice-daily loading dose on day 1) taken without regard to food intake during the neutropenic period for ≤28 days. The exposure target was reached (day 8) in 15 of 19 (79%) pharmacokinetic-evaluable patients taking 200 mg posaconazole once daily and in 31 of 32 (97%) patients taking 300 mg posaconazole once daily; 300 mg posaconazole once daily achieved the desired exposure target. Posaconazole tablets were generally well tolerated in high-risk neutropenic patients. (This study has been registered at ClinicalTrials.gov under registration no. NCT01777763.)

Letermovir Prophylaxis for Cytomegalovirus in Hematopoietic-Cell Transplantation

Background Cytomegalovirus (CMV) infection remains a common complication after allogeneic hematopoietic‐cell transplantation. Letermovir is an antiviral drug that inhibits the CMV–terminase complex. Methods In this phase 3, double‐blind trial, we randomly assigned CMV‐seropositive transplant recipients, 18 years of age or older, in a 2:1 ratio to receive letermovir or placebo, administered orally or intravenously, through week 14 after transplantation; randomization was stratified according to trial site and CMV disease risk. Letermovir was administered at a dose of 480 mg per day (or 240 mg per day in patients taking cyclosporine). Patients in whom clinically significant CMV infection (CMV disease or CMV viremia leading to preemptive treatment) developed discontinued the trial regimen and received anti‐CMV treatment. The primary end point was the proportion of patients, among patients without detectable CMV DNA at randomization, who had clinically significant CMV infection through week 24 after transplantation. Patients who discontinued the trial or had missing end‐point data at week 24 were imputed as having a primary end‐point event. Patients were followed through week 48 after transplantation. Results From June 2014 to March 2016, a total of 565 patients underwent randomization and received letermovir or placebo beginning a median of 9 days after transplantation. Among 495 patients with undetectable CMV DNA at randomization, fewer patients in the letermovir group than in the placebo group had clinically significant CMV infection or were imputed as having a primary end‐point event by week 24 after transplantation (122 of 325 patients [37.5%] vs. 103 of 170 [60.6%], P<0.001). The frequency and severity of adverse events were similar in the two groups overall. Vomiting was reported in 18.5% of the patients who received letermovir and in 13.5% of those who received placebo; edema in 14.5% and 9.4%, respectively; and atrial fibrillation or flutter in 4.6% and 1.0%, respectively. The rates of myelotoxic and nephrotoxic events were similar in the letermovir group and the placebo group. All‐cause mortality at week 48 after transplantation was 20.9% among letermovir recipients and 25.5% among placebo recipients. Conclusions Letermovir prophylaxis resulted in a significantly lower risk of clinically significant CMV infection than placebo. Adverse events with letermovir were mainly of low grade. (Funded by Merck; ClinicalTrials.gov number, NCT02137772; EudraCT number, 2013‐003831‐31.)

Phase 3 pharmacokinetics and safety study of a posaconazole tablet formulation in patients at risk for invasive fungal disease

BACKGROUND Antifungal prophylaxis with a new oral tablet formulation of posaconazole may be beneficial to patients at high risk for invasive fungal disease. A two-part (Phase 1B/3) study evaluated posaconazole tablet pharmacokinetics (PK) and safety. METHODS Patients with neutropenia following chemotherapy for haematological malignancy or recipients of allogeneic HSCT receiving prophylaxis or treatment for graft-versus-host disease received 300 mg posaconazole (as tablets) once daily (twice daily on day 1) for up to 28 days without regard to food intake. Weekly trough PK sampling was performed during therapy, and a subset of patients had sampling on days 1 and 8. Cmin-evaluable subjects received ≥6 days of dosing, and were compliant with specified sampling timepoints. Steady-state PK parameters, safety, clinical failure and survival to day 65 were assessed. ClinicalTrials.gov, NCT01777763; EU Clinical Trials Register, EUDRA-CT 2008-006684-36. RESULTS Two hundred and ten patients received 300 mg posaconazole (as tablets) once daily. Among Cmin-evaluable subjects (n = 186), steady-state mean Cmin was 1720 ng/mL (range = 210-9140). Steady-state Cmin was ≥700 ng/mL in 90% of subjects with 5% (10 of 186) <500 ng/mL and 5% (10 of 186) 500-700 ng/mL. Six (3%) patients had steady-state Cmin ≥3750 ng/mL. One patient (<1%) had an invasive fungal infection. The most common treatment-related adverse events were nausea (11%) and diarrhoea (8%). There was no increase in adverse event frequency with higher posaconazole exposure. CONCLUSIONS In patients at high risk for invasive fungal disease, 300 mg posaconazole (as tablets) once daily was well tolerated and demonstrated a safety profile similar to that reported for posaconazole oral suspension: most patients (99%) achieved steady-state pCavg exposures >500 ng/mL and only one patient (<1%) had a pCavg <500 ng/mL.

How generalizable are the results from trials of Direct Antiviral Agents to people coinfected with HIV/Hepatitis C virus in the real world?

Trial results are used to support licensure, inform cost-effectiveness analyses, and guide clinical decision making. We found the majority of coinfected patients were not included in clinical trials of direct-acting antivirals, raising concerns about the generalizability of these trial results.

Epidemiology and Outcome of Pneumonia Caused by Methicillin-Resistant Staphylococcus aureus (MRSA) in Canadian Hospitals

Background MRSA remains a leading cause of hospital-acquired (HAP) and healthcare-associated pneumonia (HCAP). We describe the epidemiology and outcome of MRSA pneumonia in Canadian hospitals, and identify factors contributing to mortality. Methods Prospective surveillance for MRSA pneumonia in adults was done for one year (2011) in 11 Canadian hospitals. Standard criteria for MRSA HAP, HCAP, ventilator-associated pneumonia (VAP), and community-acquired pneumonia (CAP) were used to identify cases. MRSA isolates underwent antimicrobial susceptibility testing, and were characterized by pulsed-field gel electrophoresis (PFGE) and Panton-Valentine leukocidin (PVL) gene detection. The primary outcome was all-cause mortality at 30 days. A multivariable analysis was done to examine the association between various host and microbial factors and mortality. Results A total of 161 patients with MRSA pneumonia were identified: 90 (56%) with HAP, 26 (16%) HCAP, and 45 (28%) CAP; 23 (14%) patients had VAP. The mean (± SD) incidence of MRSA HAP was 0.32 (± 0.26) per 10,000 patient-days, and of MRSA VAP was 0.30 (± 0.5) per 1,000 ventilator-days. The 30-day all-cause mortality was 28.0%. In multivariable analysis, variables associated with mortality were the presence of multiorgan failure (OR 8.1; 95% CI 2.5-26.0), and infection with an isolate with reduced susceptibility to vancomycin (OR 2.5, 95% CI 1.0-6.3). Conclusions MRSA pneumonia is associated with significant mortality. Severity of disease at presentation, and infection caused by an isolate with elevated MIC to vancomcyin are associated with increased mortality. Additional studies are required to better understand the impact of host and microbial variables on outcome.

Therapeutic drug monitoring for triazoles: A needs assessment review and recommendations from a Canadian perspective

Therapeutic drug monitoring (TDM) is necessary for certain drugs to ensure that the levels are sufficient to be effective, but not so high as to cause adverse effects. This review summarizes the literature regarding TDM for newer-generation extended-spectrum triazoles, including when TDM may be necessary for each drug and why, and laboratory techniques used for the measurement of levels of these drugs. The document includes recommendations for the use of TDM for each triazole that is discussed.

CIHR Canadian HIV Trials Network Coinfection and Concurrent Diseases Core Research Group: 2016 Updated Canadian HIV/Hepatitis C Adult Guidelines for Management and Treatment.

Background. Hepatitis C virus (HCV) coinfection occurs in 20–30% of Canadians living with HIV and is responsible for a heavy burden of morbidity and mortality. Purpose. To update national standards for management of HCV-HIV coinfected adults in the Canadian context with evolving evidence for and accessibility of effective and tolerable DAA therapies. The document addresses patient workup and treatment preparation, antiviral recommendations overall and in specific populations, and drug-drug interactions. Methods. A standing working group with HIV-HCV expertise was convened by The Canadian Institute of Health Research HIV Trials Network to review recently published HCV antiviral data and update Canadian HIV-HCV Coinfection Guidelines. Results. The gap in sustained virologic response between HCV monoinfection and HIV-HCV coinfection has been eliminated with newer HCV antiviral regimens. All coinfected individuals should be assessed for interferon-free, Direct Acting Antiviral HCV therapy. Regimens vary in content, duration, and success based largely on genotype. Reimbursement restrictions forcing the use of pegylated interferon is not acceptable if optimal patient care is to be provided. Discussion. Recommendations may not supersede individual clinical judgement. Treatment advances published since December 2015 are not considered in this document.

Systemic Therapy of New World Cutaneous Leishmaniasis: A Case Report and Review Article

Cutaneous leishmaniasis is a disease endemic to Central and South America, Mexico and the Caribbean, and affects millions of people. As travel to these regions becomes more common, cutaneous leishmaniasis is becoming a disease of increasing importance in the developed world. However, disease recognition and access to appropriate therapy for cutaneous leishmaniasis remains a challenge in North America. The present article reports a case of cutaneous leishmaniasis in a Canadian man following a trip to Costa Rica. Species-specific diagnosis was confirmed by polymerase chain reaction analysis of a skin biopsy, which was positive for Leishmania panamensis. After failing a course of itraconazole, the patient was successfully treated with sodium stibogluconate, despite significant barriers to administering this therapy, and the paucity of data regarding its efficacy and tolerability. The pathophysiology, diagnosis and systemic treatment of cutaneous leishmaniasis, as well as its emerging presence in the developed world, are reviewed.

Melioidosis in a Returned Traveller

Melioidosis is an infection endemic to Southeast Asia and Northern Australia, and is associated with significant morbidity and mortality. The present report describes a case of chronic melioidosis in a returning traveller from the Philippines. Clinical suspicion of this illness is warranted in individuals with a history of travel to endemic regions. Safety in handling clinical specimens is paramount because laboratory transmission has been described.

Successful Use of Posaconazole to Treat Invasive Cutaneous Fungal Infection in a Liver Transplant Patient on Sirolimus

Fungi are an important and common cause of cutaneous infections affecting solid organ transplant recipients. These infections can represent a primary site of infection with the potential for dissemination, or a manifestation of metastatic infection. The high morbidity and mortality associated with these infections necessitates urgent therapy with antifungal drugs; however, the interaction between these drugs and immunosuppressive therapies can be a major limitation because of drug toxicity. A case of soft tissue infection of the toe caused by Fusarium chlamydosporum and Candida guilliermondii in a liver transplant patient on sirolimus, who was successfully treated with the new antifungal agent posaconazole, is described. The pharmacokinetic interactions of sirolimus and the new triazoles, and their impact on treatment choices are briefly discussed.