CROI 2017 Abstract e-Book

Abstract eBook

Poster and Themed Discussion Abstracts

Poster and Themed Discussion Abstracts

682 A RANDOMIZED TRIAL OF VITAMIN D3 (3000 VERSUS 1000 IU) IN HIV+ POSTMENOPAUSAL WOMEN Michael T. Yin 1 , Chengchen Zhang 1 , Mariana Bucovsky 1 , David Ferris 2 , Susan Olender 1 , Arindam Roy Choudhury 1 , Anjali Sharma 3 , Cosmina Zeana 4 , Barry S. Zingman 5 , Elizabeth Shane 1 1 Columbia Univ, New York, NY, USA, 2 Columbia Univ, New York, NY, USA, 3 Icahn Sch of Med at Mt Sinai, New York, NY, USA, 4 Albert Einstein Coll of Med, Bronx, NY, USA, 5 Bronx Lebanon Hosp Cntr, Bronx, NY, USA, 6 Montefiore Med Cntr, Bronx, NY, USA Background: In HIV+ postmenopausal women, we observed an association between lower total 25-hydroxy vitamin D (25OHD) levels and greater bone loss at the distal radius. Since VitD supplementation improves musculoskeletal outcomes in older women, we compared the effects of Moderate (3000 IU) vs Low (1000 IU) VitD3 supplementation on bone mineral density (BMD) and bone turnover markers in HIV+ postmenopausal women on stable antiretroviral regimens Methods: A 12-month prospective, randomized, double-blind, placebo-controlled study performed at a single center with the following outcomes: BMD measured by dual- energy X-ray absorptiometry (DXA); 25OHD, parathyroid hormone (PTH), and bone turnover markers (P1NP, a marker of bone formation and CTX, a marker of bone resorption). Regression analyses were used to test for associations between baseline 25OHD and percent change in BMD and bone turnover markers for each study arm. Results: 83 participants were randomized (41 Moderate and 42 Low); 69 with 12-month DXA data were included in the primary intent-to-treat analysis. The study arms were well- balanced at baseline: median age 56 years; 55% African American, 45% Hispanic; median CD4 count 724 cells/mm3; median total 25OHD 19.7 ng/mL (49.3 nmol/L). Baseline BMI was lower in the Moderate VitD group (29±6 vs 32±6 kg/m2, p=0.02). Levels of total 25OHD were higher in the Moderate than Low VitD group at 6 months (33.1±10.3 vs 27.8±8.1 ng/ml, p=0.03) and 12 months (30.2±9.6 vs 24.3±7.6 ng/ml, p=0.007), but PTH levels did not differ between groups. In the Low VitD group, there was a significant decrease in BMD at the distal and ultradistal radius. However, percent change in BMD and bone turnover markers did not differ between Moderate and Low VitD groups after adjustment for baseline BMD and BMI (Table). In regression analyses, lower baseline 25OHD levels in the Moderate VitD group were associated with greater increase in BMD at the femoral neck (p=0.04) and ultra distal radius (p=0.045) at 12 months. Conclusion: VitD supplementation at 3000 IU daily increased mean total 25OHD levels to > 30 ng/ml in HIV+ postmenopausal women, but did not result in increases in BMD or suppression of bone turnover markers compared with 1000 IU daily. This suggests that VitD repletion by itself does not adequately prevent bone loss in HIV+ postmenopausal women. Additional interventions are likely necessary to prevent or reverse bone loss in this population.

683 SWITCHING FROM TDF TO TAF IN HIV-INFECTED ADULTS WITH LOW BMD: A POOLED ANALYSIS

Todd Brown 1 , Michael T. Yin 2 , Samir Gupta 3 , Christine Katlama 4 , Adriano Lazzarin 5 , Kathy Melbourne 6 , Calvin Cohen 6 , YaPei Liu 6 , Thai Nguyen-Cleary 6 , Scott McCallister 6 1 The Johns Hopkin Univ, Baltimore, MD, USA, 2 Columbia Univ, New York, NY, USA, 3 Indiana Univ, Indianapolis, IN, USA, 4 Pierre and Marie Curie Univ, Paris, France, 5 Vita-Salute San Raffaele Univ, Milan, Italy, 6 Gilead Scis, Inc, Foster City, CA, USA Background: Switching from tenofovir disoproxil fumarate (TDF) to tenofovir alafenamide (TAF) may represent an important treatment strategy to improve bone health in HIV- infected individuals with low bone mineral density (BMD), but this has not been specifically investigated. Methods: This analysis consisted of pooled data from two prospective Phase 3 studies (Studies 109 and 112) of HIV suppressed adults on a TDF-based regimen switching to elvitegravir, cobicistat, and emtricitabine (E/C/F) co-formulated with TAF. In adults with clinically significant low BMD by dual energy x-ray absorptiometry (T-score ≤ -2.0 at the lumbar spine, femoral neck, or total hip) at baseline (BL), we assessed percentage change in BMD and T-score at the lumbar spine and total hip and change in proportion with osteoporosis (T-score ≤ -2.5 at any site) at Weeks (W) 96. Logistic regression was used to determine BL predictors of a clinically significant improvement (≥ 5% increase) in lumbar spine and total hip BMD, adjusted for age, race, sex, and BL BMD. Results: Of the 1117 enrolled who switched from TDF to TAF, 214 (19%) had clinically significant low BMD at BL (median age 46 years, 85%male, 63%White, 26% smokers) with 43% (93/214) osteoporosis. The BL median (interquartile range: Q1, Q3) T-score (lowest of any 3 sites) was -2.4 (-2.8, -2.2). At the spine, the median (Q1, Q3) % BMD change at W96

CROI 2017 297