Collins, Gary

Background: Persistent inflammation and incomplete immune recovery among persons with HIV (PHIV) are associated with increased disease risk. We hypothesized that the angiotensin receptor blocker (ARB) losartan would reduce inflammation by mitigating nuclear factor (NF)κB responses and promote T-cell recovery via inhibition of transforming growth factor-beta (TGFβ)-mediated fibrosis. Methods: Losartan (100 mg) versus placebo over 12 months was investigated in a randomized (1 : 1) placebo-controlled trial, among PHIV age at least 50 years, receiving antiretroviral therapy (ART), with HIV RNA less than 200 copies/ml and CD4+ cell count 600 cells/μl or less. Inflammation, fibrosis and myocardial biomarkers were measured in blood using ELISA, electrochemiluminescence and immunoturbidimetric methods, and T-cell and monocyte phenotypes were assessed with flow cytometry among a subset of participants. Changes over follow-up in (log-2 transformed) biomarkers and cell phenotypes (untransformed) were compared between losartan and placebo arms using linear mixed models. Results: Among 108 PHIV (n = 52 to losartan; n = 56 to placebo), 97% had a month 12 visit. Median age was 57 years and baseline CD4+ cell count was 408 cells/μl. Losartan treatment was not associated with an improvement in interleukin-6 levels, or other blood measures of inflammation, immune activation, fibrosis activity or myocardial function. CD4+ and CD8+ T cells also did not differ by treatment group. Losartan reduced SBP and DBP by 6 and 5 mmHg, respectively. Conclusion: Among older PHIV with viral suppression, losartan did not improve blood measures of inflammation nor T-cell immune recovery. Losartan treatment is unlikely to reduce inflammation associated comorbidities to a clinically meaningful degree, beyond the benefits from lowering blood pressure. ClinicalTrials.gov: NCT02049307.

Abstract Background CDI is an important cause of morbidity and mortality in SOT and HCT patients (pts). In retrospective single-center analyses, severe disease and relapse were common. We undertook a multicenter prospective observational study to evaluate outcomes of CDI among both SOT and HCT patients. Methods Adults with a first episode of CDI, defined as 3 liquid stools/24 h with the detection of C. difficile toxin in stool, within the first 2 years of SOT or HCT were recruited from 12 centers internationally in the INSIGHT network. At enrollment, demographics, comorbidities, medication histories and outcomes were collected prospectively over 90 days to assess clinical cure, recurrences and complications and to define baseline risk factors for clinical cure and recurrent CDI. Results 132 patients (81 SOT, 51 HCT (32 allogeneic)) were enrolled: median age 56 years, 62.1% were males, 97% were hospitalized. 80.3% were diagnosed by DNA assay. CDI occurred a median of 20 days post transplant (IQR: 6–133). 108 patients were on PPIs. 98.5% were on antibiotics before CDI. 1st line treatment regimen was oral vancomycin in 66 patients (40 SOT, 26 HCT), metronidazole in 48 patients (27 SOT, 21 HCT), both drugs in 14 (10 SOT, 4 HCT), fidaxomicin (3) and linezolid (1). Rejection within 60 days before CDI was uncommon (6.2% SOT) as was GVHD (27.5%). 110 patients (83%, 95% CI: 46–89)) (65 SOT, 45 HCT) had clinical cure; 18% (95% CI: 11–27) had recurrent CDI, 2 were admitted to the ICU due to CDI, 11 (8.3%) died (2 HCT related to CDI). Among baselines variables, only first-line regimen was associated with a higher rate of clinical cure (P = 0.003), most notably for SOT. Factors that did not have a statistically significant negative impact on clinical cure included sex, age > 60, race, country, transplant type, steroids, diabetes, CMV viremia/disease, WBC > 15,000, creatinine > 1.5 mg/dL, or specific antibiotic given prior to CDI. Higher recurrence rates were associated with metronidazole-only regimen (OR: 4.6, 95% CI: 1.6–12.8; P = 0.004) and a history of CMV after transplant (OR: 5.2, 95% CI: 1.7–15.7; P = 0.003). Conclusion Despite their immunosuppressed state, recurrence, ICU admission and mortality occurred in a minority of SOT and HCT with CDI. Initial use of metronidazole and CMV viremia/disease were associated with higher recurrence rates. Disclosures All authors: No reported disclosures.