A Novel Encochleated Formulation Improves Atovaquone Activity in a Murine Model of Pneumocystis Pneumonia.

Although atovaquone is effective in treating and preventing Pneumocystis pneumonia (PCP), its use is limited by nonlinear absorption and adverse events. The current study was undertaken to examine the activity of encochleated atovaquone (eATQ), a novel lipid-crystal nanoparticle formulation, in a mouse model of PCP. eATQ 100-200 mg was superior to commercially available atovaquone at 14 days in decreasing total Pneumocystis nuclei and asci. eATQ plus anidulafungin reduced nuclei significantly better than commercial atovaquone plus anidulafungin. eATQ is a novel formulation of atovaquone that warrants further evaluation for treatment and prevention of PCP.

Safety and efficacy of low-dose sirolimus in the PIK3CA-related overgrowth spectrum.

PURPOSE: PIK3CA-related overgrowth spectrum (PROS) encompasses a range of debilitating conditions defined by asymmetric overgrowth caused by mosaic activating PIK3CA variants. PIK3CA encodes the p110α catalytic subunit of phosphatidylinositol-3-kinase (PI3K), a critical transducer of growth factor signaling. As mTOR mediates the growth-promoting actions of PI3K, we hypothesized that the mTOR inhibitor sirolimus would slow pathological overgrowth. METHODS: Thirty-nine participants with PROS and progressive overgrowth were enrolled into open-label studies across three centers, and results were pooled. For the primary outcome, tissue volumes at affected and unaffected sites were measured by dual energy X-ray absorptiometry during 26 weeks of untreated run-in and 26 weeks of sirolimus therapy. RESULTS: Thirty participants completed the study. Sirolimus led to a change in mean percentage total tissue volume of -7.2% (SD 16.0, p = 0.04) at affected sites, but not at unaffected sites (+1.7%, SD 11.5, p = 0.48) (n = 23 evaluable). Twenty-eight of 39 (72%) participants had ≥1 adverse event related to sirolimus of which 37% were grade 3 or 4 in severity and 7/39 (18%) participants were withdrawn consequently. CONCLUSION: This study suggests that low-dose sirolimus can modestly reduce overgrowth, but cautions that the side-effect profile is significant, mandating individualized risk-benefit evaluations for sirolimus treatment in PROS.

Cytokine-Mediated Systemic Adverse Drug Reactions in a Drug-Drug Interaction Study of Dolutegravir With Once-Weekly Isoniazid and Rifapentine.

Background: Once-weekly isoniazid and rifapentine for 3 months is a treatment option in persons with human immunodeficiency virus and latent tuberculosis infection. This study aimed to examine pharmacokinetic drug-drug interactions between this regimen and dolutegravir, a first-line antiretroviral medication. Methods: This was a single-center, open-label, fixed-sequence, drug-drug interaction study in healthy volunteers. Subjects received oral dolutegravir 50 mg once daily alone (days 1-4) and concomitantly with once-weekly isoniazid 900 mg, rifapentine 900 mg, and pyridoxine 50 mg (days 5-19). Dolutegravir concentrations were measured on days 4, 14, and 19, and rifapentine, 25-desacetyl-rifapentine, and isoniazid concentrations were measured on day 19. Cytokines and antidrug antibodies to isoniazid and rifapentine were examined at select time points. Results: The study was terminated following the development of flu-like syndrome and elevated aminotransferase levels in 2 of 4 subjects after the third isoniazid-rifapentine dose. Markedly elevated levels of interferon-γ, CXCL10, C-reactive protein, and other cytokines were temporally associated with symptoms. Antidrug antibodies were infrequently detected. Dolutegravir area under the curve (AUC) was decreased by 46% (90% confidence interval, 27-110%; P = .13) on day 14. Rifapentine and 25-desacetyl rifapentine levels on day 19 were comparable to reference data, whereas isoniazid AUCs were approximately 67%-92% higher in the subjects who developed toxicities. Conclusions: The combined use of dolutegravir with once-weekly isoniazid-rifapentine resulted in unexpected and serious toxicities that were mediated by endogenous cytokine release. Additional investigations are necessary to examine the safety and efficacy of coadministering these medications. Clinical Trials Registration: NCT02771249.

Long-term use of continuous subcutaneous hydrocortisone infusion therapy in patients with congenital adrenal hyperplasia.

BACKGROUND: In a phase 2 short-term (6 months) study of patients with congenital adrenal hyperplasia (CAH), continuous subcutaneous hydrocortisone infusion (CSHI) was found to be a safe, effective and well-tolerated method of replacing cortisol with improved disease and patient-related outcomes. OBJECTIVE: To evaluate the safety and efficacy of long-term CSHI. DESIGN: Single-centre, open-label, phase 2 extension study. PATIENTS: Five adults with classic CAH. MEASUREMENTS: Biomarkers of disease control, metabolic indices and health-related quality-of-life (HRQoL) estimates. RESULTS: Six of eight patients chose to continue on long-term CSHI therapy. Compared to baseline, eighteen months of CSHI resulted in decreased (P = 0.043) 0700-hour ACTH, 17-hydroxyprogesterone, androstenedione and progesterone; increased whole-body lean mass (P = 0.024); and improved HRQoL, especially symptoms of adrenal insufficiency (P = 0.003). Findings at six and eighteen months did not differ, and improvements achieved in androgen control, lean body mass and HRQoL after 6 months of CSHI were maintained at eighteen months. The hydrocortisone dose appeared to decrease with time [6 vs 18 months: 38.3 ± 8.8 vs 33.6 ± 12.2 mg/day (P = 0.062)], especially in women receiving oral contraceptives. Reduction of testicular adrenal rest and adrenal size observed at 6 months remained stable. In one patient, an adrenal adenoma continually decreased over time. Subjective improvement in hirsutism was reported. CONCLUSIONS: Long-term use of CSHI is a safe and well-tolerated treatment option in a select set of adults with classic CAH. Improvements observed short term in disease control and subjective health status continued long term.

Safety, tolerability, and pharmacokinetics of radavirsen (AVI-7100), an antisense oligonucleotide targeting influenza a M1/M2 translation.

AIMS: The aims of the present study were to assess the safety, tolerability and pharmacokinetics of radavirsen following single ascending doses and multiple doses given as intravenous infusions in healthy adults. METHODS: A phase I safety and pharmacokinetic study of radavirsen was performed in healthy volunteers. The study was divided into two parts. The first was a single-ascending-dose study of five cohorts of eight subjects each, randomized 6:2 to receive single intravenous doses of radavirsen ranging from 0.5 mg kg-1 to 8 mg kg-1 or placebo. The second was a multiple-dose study of 16 subjects randomized 12:4 to receive 8 mg kg-1 or placebo once daily for 5 days. RESULTS: A total of 66 subjects were screened, and 56 subjects were dosed between 2013 and 2015. At least one adverse event occurred in 31/42 (74%) who received radavirsen, and 13/14 (93%) receiving placebo. The most common adverse events were headache and proteinuria, and were similar in incidence and severity among those receiving radavirsen or placebo. Single-dose pharmacokinetics demonstrated relatively linear and dose-proportional increases in maximal concentration and in area under the concentration-time curve from zero to 24 h (AUC0-24 ). At 8 mg kg-1 in the multiple-dose cohort, the day 4 geometric mean AUC0-24 was 57.9 µg*h ml-1 . CONCLUSION: Single infusions of radavirsen up to 8 mg kg-1 , and multi-dosing at 8 mg kg-1 once daily for 5 days, appear to be safe and well tolerated in healthy subjects. The multi-dose day 4 AUC0-24 in the present study was comparable with that associated with protection from viral infection in a preclinical ferret influenza model. Further evaluation of radavirsen for the treatment of influenza infections is warranted.

Differential Influence of the Antiretroviral Pharmacokinetic Enhancers Ritonavir and Cobicistat on Intestinal P-Glycoprotein Transport and the Pharmacokinetic/Pharmacodynamic Disposition of Dabigatran.

Dabigatran etexilate (DE) is a P-glycoprotein (P-gp) probe substrate, and its active anticoagulant moiety, dabigatran, is a substrate of the multidrug and toxin extrusion protein-1 (MATE-1) transporter. The antiretroviral pharmacokinetic enhancers, ritonavir and cobicistat, inhibit both these transporters. Healthy volunteers received single doses of DE at 150 mg alone, followed by ritonavir at 100 mg or cobicistat at 150 mg daily for 2 weeks. DE was then given 2 h before ritonavir or cobicistat. One week later, DE was given simultaneously with ritonavir or cobicistat. No significant increases in dabigatran pharmacokinetic (PK) exposure or thrombin time (TT) measures were observed with the simultaneous administration of ritonavir. Separated administration of ritonavir resulted in a mean decrease in dabigatran PK exposure of 29% (90% confidence interval [CI], 18 to 40%) but did not significantly change TT measures. However, cobicistat increased dabigatran PK exposure (area under the concentration-versus-time curve from time zero to infinity and maximum plasma concentration) by 127% each (90% CI, 81 to 173% and 59 to 196%, respectively) and increased TT measures (33% for the area-under-the-effect curve from time zero to 24 h [90% CI, 22 to 44%] and 51% for TT at 24 h [90% CI, 22 to 78%]) when given simultaneously with dabigatran. Similar increases were observed when cobicistat was administered separately by 2 h from the administration of dabigatran. In all comparisons, no significant increase in the dabigatran elimination half-life was observed. Therefore, it is likely safe to coadminister ritonavir with DE, while there is a potential need for reduced dosing and prudent clinical monitoring with the coadministration of cobicistat due to the greater net inhibition of intestinal P-gp transport and increased bioavailability. (This study has been registered at ClinicalTrials.gov under identifier NCT01896622.).

Efavirenz but Not Atazanavir/Ritonavir Significantly Reduces Atovaquone Concentrations in HIV-Infected Subjects.

BACKGROUND: The current study was conducted to determine if efavirenz (EFV) or atazanavir/ritonavir (ATV/r)-based combination antiretroviral therapy (cART) impacted steady-state atovaquone plasma concentrations in human immunodeficiency virus (HIV)-infected patients receiving treatment doses of atovaquone. METHODS: Thirty HIV-infected volunteers were recruited, 10 taking no cART and 10 each taking cART that included EFV or ATV/r. Subjects were randomly assigned to atovaquone 750 mg twice daily (BID) for 14 days followed by atovaquone 1500 mg BID for 14 days, or vice-versa, with a washout period in between. On day 14 of each phase, blood was sampled for pharmacokinetic studies, and the area under the concentration-time curve (AUCτ) and average concentration (C avg) were calculated and compared using an unpaired t test. RESULTS: Twenty-nine subjects completed both dosing cohorts. Subjects receiving EFV-based cART had 47% and 44% lower atovaquone AUCτ than subjects not receiving cART at atovaquone doses of 750 mg BID and 1500 mg BID, respectively (P≤ .01). Only 5 of 10 subjects receiving EFV-based cART plus atovaquone 750 mg BID had an atovaquone C avg>15 µg/mL, which has previously been associated with successful treatment of Pneumocystis jirovecipneumonia. AUCτ and Cavg did not significantly differ for concurrent ATV/r for 750 mg BID or 1500 mg BID when compared to the group not receiving cART. Nine of 10 subjects not receiving cART, 8 of 10 subjects receiving ATV/r, and 2 of 10 subjects receiving EFV in combination with atovaquone 750 mg BID achieved an atovaquone C avg>18.5 µg/mL, a concentration that has previously been associated with successful treatment of Toxoplasmaencephalitis (TE). CONCLUSIONS: These data suggest that the currently recommended dose of atovaquone 750 mg BID for treatment of mild to moderate PCP may not be adequate in patients receiving concurrent EFV. Furthermore, doses lower than the currently recommended dose of 1500 mg BID may achieve plasma concentrations adequate to treat TE in HIV-infected patients not receiving EFV. CLINICAL TRIALS REGISTRATION: NCT01479361.

Comparison of serum creatinine and serum cystatin C as biomarkers to detect sepsis-induced acute kidney injury and to predict mortality in CD-1 mice.

Acute kidney injury (AKI) dramatically increases sepsis mortality, but AKI diagnosis is delayed when based on serum creatinine (SCr) changes, due in part, to decreased creatinine production. During experimental sepsis, we compared serum cystatin C (sCysC), SCr, and blood urea nitrogen (BUN) to inulin glomerular filtration rate (iGFR) before or 3-18 h after cecal ligation and puncture (CLP)-induced sepsis in CD-1 mice. sCysC had a faster increase and reached peak levels more rapidly than SCr in both sepsis and bilateral nephrectomy (BiNx) models. sCysC was a better surrogate of iGFR than SCr during sepsis. Combining sCysC with SCr values into a composite biomarker improved correlation with iGFR better than any biomarker alone or any other combination. We determined the renal contribution to sCysC handling with BiNx. sCysC and SCr were lower post-BiNx/CLP than post-BiNx alone, despite increased inflammatory and nonrenal organ damage biomarkers. Sepsis decreased CysC production in nephrectomized mice without changing body weight or CysC space. Sepsis decreased sCysC production and increased nonrenal clearance, similar to effects of sepsis on SCr. sCysC, SCr, and BUN were measured 6 h postsepsis to link AKI with mortality. Mice with above-median sCysC, BUN, or SCr values 6 h postsepsis died earlier than mice with below-median values, corresponding to a substantial AKI association with sepsis mortality in this model. sCysC performs similarly to SCr in classifying mice at risk for early mortality. We conclude that sCysC detects AKI early and better reflects iGFR in CLP-induced sepsis. This study shows that renal biomarkers need to be evaluated in specific contexts.

Translational studies of phenotypic probes for the mononuclear phagocyte system and liposomal pharmacology.

As nanoparticles (NPs) are cleared via phagocytes of the mononuclear phagocyte system (MPS), we hypothesized that the function of circulating monocytes and dendritic cells (MO/DC) in blood can predict NP clearance (CL). We measured MO/DC phagocytosis and reactive oxygen species (ROS) production in mice, rats, dogs, and patients with refractory solid tumors. Pharmacokinetic studies of polyethylene glycol (PEG)-encapsulated liposomal doxorubicin (PEGylated liposomal doxirubicin [PLD]), CKD-602 (S-CKD602), and cisplatin (SPI-077) were performed at the maximum tolerated dose. MO/DC function was also evaluated in patients with recurrent epithelial ovarian cancer (EOC) administered PLD. Across species, a positive association was observed between cell function and CL of PEGylated liposomes. In patients with EOC, associations were observed between PLD CL and phagocytosis (R(2) = 0.43, P = 0.04) and ROS production (R(2) = 0.61, P = 0.008) in blood MO/DC. These findings suggest that probes of MPS function may help predict PEGylated liposome CL across species and PLD CL in patients with EOC.

Lack of a pharmacokinetic interaction between treprostinil diolamine and sildenafil in healthy adult volunteers.

Treprostinil, a stable prostacyclin analogue used in the treatment of pulmonary arterial hypertension, is in development as a sustained release oral tablet, treprostinil diolamine (United Therapeutics Corp, Research Triangle Park, NC). As combination therapy yields additional benefit in pulmonary arterial hypertension, treprostinil diolamine may be used with sildenafil, a phosphodiesterase-5 inhibitor. This study was designed to evaluate the presence of a pharmacokinetic drug interaction between treprostinil diolamine and sildenafil. Treprostinil is primarily metabolized by cytochrome (CYP) P450 2C8 with minor contribution from CYP2C9. Sildenafil is metabolized by CYP3A4 with minor contribution from CYP2C9. Eighteen healthy volunteers were randomized to receive 4.5 days each of (1) treprostinil diolamine alone, (2) sildenafil alone, and (3) combination treprostinil diolamine and sildenafil in an open-label, 3-period, 3-sequence crossover study. The geometric mean ratio (90% confidence intervals) for combination/agent alone of steady state area under the concentration-time curve and peak concentration (Cmax) were 0.972 (0.824-1.145) and 1.030 (0.900, 1.1-9), respectively, for treprostinil diolamine and were 0.881 (0.804-0.966) and 0.910 (0.876-0.946), respectively, for sildenafil. The results suggest lack of a metabolic interaction between treprostinil diolamine and sildenafil, as geometric mean ratio 90% confidence intervals were within 0.8-1.25. Combination therapy was well tolerated but had slightly higher rates of nausea, headache, and extremity pain than monotherapy.

Community-acquired pneumonia with risk for drug-resistant pathogens.

BACKGROUND: Pneumonia is a leading infectious cause of morbidity and mortality in the United States. The Infectious Disease Society of America (IDSA) and American Thoracic Society (ATS) have published treatment guidelines for community-acquired pneumonia (CAP) based upon the site of acquisition and specific pathogen risk. The literature demonstrates improved outcomes with guideline-concordant empiric therapy. A subset of patients with CAP has risk factors for drug-resistant pathogens (DRPs). IDSA/ATS treatment guidelines do not provide clear recommendations for empiric treatment, and clinical studies have not provided descriptive data for this group. METHODS: A retrospective chart review of all admissions between January 1, 2008 and April 19, 2009 with an International Classification of Diseases-9 code and physician-documented diagnosis of pneumonia at two community hospitals were performed. IDSA pneumonia type and presence of risk factors for DRP were recorded for each patient, and the empiric antibiotic therapy received was evaluated. Admissions were excluded if immunosuppression or pregnancy was present. RESULTS: Of the 400 admissions reviewed, 343 patients were included. A total of 228 patients (71%) had CAP. Forty-three percent of patients with CAP had risk factors for DRP. Only 2% of this group received an antibiotic regimen with coverage of the specific DRP risk factor present. The most common DRPs not receiving coverage in this group were Pseudomonas aeruginosa and methicillin-resistant Staphylococcus aureus. P. aeruginosa and methicillin-resistant S. aureus occurred more commonly in culture-positive patients with CAP with DRP risk factors but did not achieve statistical significance. A larger sample size would be needed to determine whether this difference is significant. CONCLUSIONS: Risk factors for DRP occurred commonly in our CAP population. Patients with CAP with risk for DRP may be a distinct group who are without clear guidance on treatment. Future studies are needed to define the risk of DRP and the impact upon empiric therapy for patients with CAP.

Pharmacokinetics, Safety, and Tolerability of Once-Daily Darunavir With Cobicistat and Weekly Isoniazid/Rifapentine.

BACKGROUND: Once-weekly isoniazid with rifapentine (HP) for 3 months is a recommended treatment for latent tuberculosis infection in persons with HIV. HP reduces exposures of certain antiretroviral medications, resulting in limited options for the concomitant use of these therapies. Here, we examined the pharmacokinetics (PK), safety, and tolerability of darunavir/cobicistat with HP. METHODS: This was an open-label, fixed sequence, two-period crossover study in persons without HIV. Participants received darunavir 800 mg/cobicistat 150 mg once-daily alone for 4 days, then continued darunavir/cobicistat once-daily for days 5-19 with HP coadministration on days 5, 12, and 19. Intensive PK assessments were performed on days 4, 14, and 19. PK parameters were determined using noncompartmental methods. Geometric mean ratios with 90% confidence intervals (CIs) were calculated and compared between phases using mixed-effects models. RESULTS: Thirteen participants were enrolled. Two withdrew after day 4, and one withdrew after day 14. Of the 3 withdrawals, 2 were attributed to drug-related adverse events. Darunavir area under the concentration-time curve, maximum concentrations (Cmax), and concentrations at 24 hours postdose (C24h) were reduced by 71%, 41%, and 96% ∼48-72 hours after HP administration (day 14), respectively, and 36%, 17%, and 89% with simultaneous HP administration (day 19), respectively. On day 14, 45% of the predose and 73% of C24h concentrations were below the darunavir EC50 (0.055 µg/mL). CONCLUSIONS: Darunavir exposures were significantly decreased with HP coadministration. Temporal relationships between HP coadministration and the extent of induction or mixed inhibition/induction of darunavir metabolism were apparent. Coadministration of darunavir/cobicistat with 3HP should be avoided.

Leveraging patient-centric sampling for clinical drug development and decentralized clinical trials: Promise to reality.

Advances in the technologies to enable patient-centric sampling (PCS) have the potential to improve blood sample collection by enabling clinical trial participants to collect samples via self-collection or with the help of a caregiver in their home. Typically, blood samples to assess pharmacokinetics and pharmacodynamics of a drug during clinical development are collected at a clinical site via venous blood draw. In this position paper by the International Consortium for Innovation and Quality in Pharmaceutical Development (IQ), the potential value PCS can bring to patients, to the clinical datasets generated, and to clinical trial sponsors is discussed, along with considerations for program decision making, bioanalytical feasibility, operations, and regulatory implications. With an understanding of the value of PCS and considerations when implementing during clinical drug development, we can bring the promise of PCS closer to reality and enable decentralized clinical trials.

The efficacy of a novel approach to transversus abdominis plane block for postoperative analgesia after colorectal surgery.

BACKGROUND: The analgesic efficacy of transversus abdominis plane (TAP) block has been established for patients undergoing abdominal surgery. We evaluated the efficacy of a novel approach to TAP block for postoperative analgesia after colorectal surgery. METHODS: Forty adult ASA physical status I to III patients undergoing colorectal surgery were recruited to this double-blind randomized controlled trial. A standard general anesthetic technique was used. TAP block was performed at the end of surgery by piercing the transversus abdominis muscle from inside the abdominal wall at the midaxillary line at the level of the umbilicus with a 22-gauge blunt needle. The patients were randomly assigned to receive either 20 mL of 0.25%bupivacaine (TAP group) or normal saline (control group) on each side of the abdominal wall. Each patient was assessed at 0, 0.5, 1, 2, 4, 8, 12, and 24 hours postoperatively for pain at rest and on coughing using a visual analog scale. IV morphine was used for postoperative rescue analgesia. Time to first request for rescue analgesia, total morphine requirement in 24 hours, cumulative morphine consumption at 2, 4, 6, 12, and 24 hours, and adverse effects (respiratory depression, sedation, nausea/vomiting) were recorded. RESULTS: A 65% decrease in 24-hour total morphine consumption was observed in the TAP group compared with the control group (P < 0.0001). The cumulative morphine requirement was also significantly lower in the TAP group at all time points. Although the time to first request for morphine was comparable, the subsequent doses of morphine were required at significantly longer time intervals in the TAP group than in the control group. TAP group patients had significantly lower pain scores at rest and on coughing as compared with the control group, at all time points assessed. The incidence of sedation was also less in the TAP group at 1, 2, 4, and 6 hours postoperatively (P < 0.05). CONCLUSIONS: This new approach to the TAP block provides effective postoperative analgesia after colorectal surgery.

Quantitative Benefit-Risk Assessment of P-gp-Mediated Drug-Drug Interactions of Dabigatran Coadministered With Pharmacokinetic Enhancers in Patients With Renal Impairment.

Drug-drug interactions (DDIs) between dabigatran and ritonavir/cobicistat are of major concern in people living with HIV, particularly in those with impaired renal function, because they can result in increased dabigatran exposure and thus an increased risk of major bleeding events. However, the extent of this interaction and subsequent need for dose adjustment in subjects with varying degrees of renal function is currently not yet fully understood. To close this knowledge gap, we conducted an integrated population physiologically-based pharmacokinetic/pharmacodynamic analysis linking changes in dabigatran exposure due to DDIs and varying degrees of renal function to the probability of experiencing an ischemic stroke or major bleeding event within 1 year. The results of our analysis suggest that coadministration of dabigatran etexilate (dabigatran prodrug) and ritonavir/cobicistat should be avoided in subjects with severe renal impairment. A 2-hour dose separation or dabigatran etexilate dose reduction to 110 mg b.i.d. (twice daily) should be considered in subjects with moderate renal impairment when coadministered with ritonavir, while the dabigatran etexilate dose should be further reduced to 75 mg b.i.d. when coadministered with cobicistat. No dabigatran etexilate dose adjustment is needed in subjects with normal renal function receiving ritonavir, but dabigatran etexilate dose reduction to 110 mg b.i.d. should be considered when coadministered with cobicistat.

A prospective evaluation on the interaction of fluconazole and voriconazole on serum concentrations of budesonide in patients treated for gastrointestinal GVHD.

The gastrointestinal (GI) tract is commonly affected by acute and chronic graft-versus-host disease (GVHD) in patients who have undergone allogeneic hematopoietic stem cell transplantation (allo-HSCT). For patients developing GI GVHD, nonabsorbable corticosteroids such as budesonide may be used alone to reduce the risk of systemic corticosteroid toxicities or combined with systemic steroids to enhance clinical responses and to allow more rapid tapering of systemic corticosteroid doses. This prospective crossover study was conducted to evaluate what effect two commonly used antifungal agents, fluconazole, and voriconazole, would have on the trough (Cmin) and peak (Cmax) levels of budesonide in adult patients who had undergone allo-HSCT who subsequently developed clinical GI GVHD. Fifteen subjects were enrolled and nine completed the study and were evaluable. When coadministered with budesonide, voriconazole significantly increased the geometric mean of budesonide Cmin and Cmax levels by 8.52- and 6.63-fold, respectively. The cohort to evaluate the interaction with fluconazole did not meet accrual goals to reach definitive conclusions. In conclusion, this prospective study demonstrated that when patients with GI GVHD are treated with budesonide concurrently with voriconazole, the systemic concentrations of budesonide increase substantially which could increase the risk of steroid-associated toxicities.

Atypical Presentation of Viral Gastroenteritis in a Three-year-old Child Due to a UNC80 Mutation.

We report a three-year-old child with a rare genetic phenomenon, a UNC80 mutation, who had an unusual presentation of viral gastroenteritis. The UNC80 gene encodes for an important voltage-independent channel in neurons and a mutation in this protein can lead to severe hypotonia. The hypotonia manifests as delayed gastric emptying, impaired respiratory clearance, and/or delayed muscle coordination, which can predispose to infection susceptibility. UNC80 gene mutations have also been shown to cause global developmental delays, failure to thrive, and phenotypic dysmorphisms. In our patient, we believe that his genetic defect precipitated a complicated hospital course. The patient's delayed gastric emptying caused difficulty in recovering from viral gastroenteritis while a concurrent pneumonia diagnosis required assistance in clearing respiratory contents. The UNC80 mutation is under-studied, and more studies are necessary to understand the clinical implications of its phenotypes.