Search

Background: Dengue is a global health problem and the development of a tetravalent dengue vaccine with durable protection is a high priority. A heterologous prime-boost strategy has the advantage of eliciting immune responses through different mechanisms and therefore may be superior to homologous prime-boost strategies for generating durable tetravalent immunity.Methods: In this phase 1 first-in-human heterologous prime-boost study, 80 volunteers were assigned to 4 groups and received a tetravalent dengue virus (DENV-1-4) purified inactivated vaccine (TDENV-PIV) with alum adjuvant and a tetravalent dengue virus (DENV-1-4) live attenuated vaccine (TDENV-LAV) in different orders and dosing schedules (28 or 180 days apart).Results: All vaccination regimens had acceptable safety profiles and there were no vaccine-related serious adverse events. TDEN-PIV followed by TDEN-LAV induced higher neutralizing antibody titers and a higher rate of tetravalent seroconversions compared to TDEN-LAV followed by TDEN-PIV. Both TDEN-PIV followed by TDEN-LAV groups demonstrated 100% tetravalent seroconversion 28 days following the booster dose, which was maintained for most of these subjects through the day 180 measurement.Conclusions: A heterologous prime-boost vaccination strategy for dengue merits additional evaluation for safety, immunogenicity, and potential for clinical benefit.Clinical Trials Registration: NCT02239614. [ABSTRACT FROM AUTHOR]

Background: Dengue human infection models (DHIM) have been used as a safe means to test the viability of prophylaxis and therapeutics.Methods: A phase 1 study of 12 healthy adult volunteers using a challenge virus, DENV-1-LVHC strain 45AZ5, was performed. A dose escalating design was used to determine the safety and performance profile of the challenge virus. Subjects were evaluated extensively until 28 days and then out to 6 months.Results: Twelve subjects received the challenge virus: 6 with 0.5 mL of 6.5 × 103 plaque-forming units (PFU)/mL (low-dose group) and 6 with 0.5 mL of 6.5 × 104 PFU/mL (mid-dose group). All except 1 in the low-dose group developed detectable viremia. For all subjects the mean incubation period was 5.9 days (range 5-9 days) and mean time of viremia was 6.8 days (range 3-9 days). Mean peak for all subjects was 1.6 × 107 genome equivalents (GE)/mL (range 4.6 × 103 to 5 × 107 GE/mL). There were no serious adverse events or long-term safety signals noted.Conclusions: We conclude that DENV-1-LVHC was well-tolerated, resulted in an uncomplicated dengue illness, and may be a suitable DHIM for therapeutic and prophylactic product testing.Clinical Trials Registration: NCT02372175. [ABSTRACT FROM AUTHOR]

Background: Plasmodium vivax malaria requires a 2-week course of primaquine (PQ) for radical cure. Evidence suggests that the hepatic isoenzyme cytochrome P450 2D6 (CYP2D6) is the key enzyme required to convert PQ into its active metabolite.Methods: CYP2D6 genotypes and phenotypes of 550 service personnel were determined, and the pharmacokinetics (PK) of a 30-mg oral dose of PQ was measured in 45 volunteers. Blood and urine samples were collected, with PQ and metabolites were measured using ultraperformance liquid chromatography with mass spectrometry.Results: Seventy-six CYP2D6 genotypes were characterized for 530 service personnel. Of the 515 personnel for whom a single phenotype was predicted, 58% had a normal metabolizer (NM) phenotype, 35% had an intermediate metabolizer (IM) phenotype, 5% had a poor metabolizer (PM) phenotype, and 2% had an ultrametabolizer phenotype. The median PQ area under the concentration time curve from 0 to ∞ was lower for the NM phenotype as compared to the IM or PM phenotypes. The novel 5,6-ortho-quinone was detected in urine but not plasma from all personnel with the NM phenotype.Conclusion: The plasma PK profile suggests PQ metabolism is decreased in personnel with the IM or PM phenotypes as compared to those with the NM phenotype. The finding of 5,6-ortho-quinone, the stable surrogate for the unstable 5-hydroxyprimaquine metabolite, almost exclusively in personnel with the NM phenotype, compared with sporadic or no production in those with the IM or PM phenotypes, provides further evidence for the role of CYP2D6 in radical cure.Clinical Trials Registration: NCT02960568. [ABSTRACT FROM AUTHOR]

Previous data are limited to describe cross-reactivity ( I n i = 4).[6],[7] Iarikov and colleagues[7] described 12 patients who had a hypersensitivity reaction to fidaxomicin, of which 3 reported a macrolide allergy. Strengths of this report include a patient cohort with multiple labelled allergies/intolerances who received a typical fidaxomicin duration of 10 days and were monitored for hypersensitivity reactions throughout fidaxomicin receipt with outpatient follow-up for most patients. However, limited published reports are currently available to describe potential cross-reactivity and hypersensitivity reactions between fidaxomicin and other macrolides.[3],[6],[7] Herein, we describe a small cohort of patients with a labelled macrolide allergy/intolerance who received fidaxomicin. [Extracted from the article]

Background: Three full doses of RTS,S/AS01 malaria vaccine provides partial protection against controlled human malaria parasite infection (CHMI) and natural exposure. Immunization regimens, including a delayed fractional third dose, were assessed for potential increased protection against malaria and immunologic responses.Methods: In a phase 2a, controlled, open-label, study of healthy malaria-naive adults, 16 subjects vaccinated with a 0-, 1-, and 2-month full-dose regimen (012M) and 30 subjects who received a 0-, 1-, and 7-month regimen, including a fractional third dose (Fx017M), underwent CHMI 3 weeks after the last dose. Plasmablast heavy and light chain immunoglobulin messenger RNA sequencing and antibody avidity were evaluated. Protection against repeat CHMI was evaluated after 8 months.Results: A total of 26 of 30 subjects in the Fx017M group (vaccine efficacy [VE], 86.7% [95% confidence interval [CI], 66.8%-94.6%]; P < .0001) and 10 of 16 in the 012M group (VE, 62.5% [95% CI, 29.4%-80.1%]; P = .0009) were protected against infection, and protection differed between schedules (P = .040, by the log rank test). The fractional dose boosting increased antibody somatic hypermutation and avidity and sustained high protection upon rechallenge.Discussions: A delayed third fractional vaccine dose improved immunogenicity and protection against infection. Optimization of the RTS,S/AS01 immunization regimen may lead to improved approaches against malaria.Clinical Trials Registration: NCT01857869. [ABSTRACT FROM AUTHOR]

Trauma-related invasive mold infections are an emerging threat among US military personnel. Early identification of suspicious wounds, based on injury profile and tissue-based diagnosis, require aggressive surgical and empiric antifungal therapy (liposomal amphotericin B and voriconazole pending histopathology and cultures).Background. Major advances in combat casualty care have led to increased survival of patients with complex extremity trauma. Invasive fungal wound infections (IFIs) are an uncommon, but increasingly recognized, complication following trauma that require greater understanding of risk factors and clinical findings to reduce morbidity.Methods. The patient population includes US military personnel injured during combat from June 2009 through December 2010. Case definition required wound necrosis on successive debridements with IFI evidence by histopathology and/or microbiology (Candida spp excluded). Case finding and data collected through the Trauma Infectious Disease Outcomes Study utilized trauma registry, hospital records or operative reports, and pathologist review of histopathology specimens.Results. A total of 37 cases were identified: proven (angioinvasion, n = 20), probable (nonvascular tissue invasion, n = 4), and possible (positive fungal culture without histopathological evidence, n = 13). In the last quarter surveyed, rates reached 3.5% of trauma admissions. Common findings include blast injury (100%) during foot patrol (92%) occurring in southern Afghanistan (94%) with lower extremity amputation (80%) and large volume blood transfusion (97.2%). Mold isolates were recovered in 83% of cases (order Mucorales, n = 16; Aspergillus spp, n = 16; Fusarium spp, n = 9), commonly with multiple mold species among infected wounds (28%). Clinical outcomes included 3 related deaths (8.1%), frequent debridements (median, 11 cases), and amputation revisions (58%).Conclusions. IFIs are an emerging trauma-related infection leading to significant morbidity. Early identification, using common characteristics of patient injury profile and tissue-based diagnosis, should be accompanied by aggressive surgical and antifungal therapy (liposomal amphotericin B and a broad-spectrum triazole pending mycology results) among patients with suspicious wounds. [ABSTRACT FROM AUTHOR]

Invasive mold infections are a rare complication of traumatic wounds. We examined the incidence and outcomes of these infections in combat wounds. A retrospective chart review from March 2002 through July 2008 of U.S. soldiers returning from Iraq and Afghanistan with traumatic wounds was performed. A confirmed fungal wound infection was defined as growth of a known pathogenic mold and visualization of fungal elements on histopathology. Six cases were identified for an incidence of 0.4 cases/1,000 admissions. The incidence of invasive mold infections increased over time (p = 0.008) with a peak of 5.2 cases/1,000 admissions in 2007. Isolated molds included Aspergillus (n = 4), BipolaHs (17 = 2), and 1 each Mucor and Absidia. All patients were male with a mean age of 22. Blast (n = 5) and gunshot wound (n = 1) were the sources of injury. All patients had fever (mean 39.4°C) and leukocytosis (mean white blood cell count 25 x 10³/µL). The average acute physiology and chronic health evaluation II score was 22. All patients received antifungal agents, surgical debridement, and 3 required amputation revision. Average length of stay was 97 days. There were no deaths. Invasive mold infections are a rare complication of combat wounds but are associated with significant morbidity and may be increasing in frequency. [ABSTRACT FROM AUTHOR]

The incidence of acute renal failure, defined by the risk, injury, or failure criteria of the RIFLE criteria (risk, injury, failure, loss, and end-stage kidney disease), in 66 patients who received colistimethate sodium was 45%, and 21% of patients stopped therapy because of nephrotoxicity. The RIFLE criteria should be used in the future to allow for comparison of nephrotoxicity among studies. [ABSTRACT FROM AUTHOR]

The article presents a case study of a 60-year-old, 76 kg male presented with septic shock requiring continuous venovenous haemodialysis (CVVHD) secondary to a recalcitrant, polymicrobial periprosthetic hip joint infection. It discusses the pharmacokinetic analysis of meropenem or vaborbactam during continuous venovenous haemodialysis. It mentions the involvement of the use of a marketed antibiotic during medical care.