410. SWIFT Study: Switching from Lamivudine/Abacavir (3TC/ABC) to Emtricitabine/Tenofovir DF (FTC/TDF) Improved Fasting Lipid Parameters While Maintaining Virologic Suppression
Session: Poster Abstract Session: HIV - Antiretroviral Therapy
Friday, October 21, 2011
Room: Poster Hall B1
  • DeJesus SWIFT IDSA 2011 FINAL.pdf (139.6 kB)
  • Background: In prior treatment naïve and experienced studies, use of TDF has been associated with more favorable fasting lipid profile. There are limited data on the impact of switching from fixed-dose 3TC/ABC to FTC/TDF, particularly in older HIV+ subjects.

    Methods: Prospective, multicenter, randomized 48 week study to evaluate the safety and efficacy of a strategy to switch subjects from 3TC/ABC to FTC/TDF. Subjects receiving 3TC/ABC + PI/r with HIV RNA < 200c/mL ³ 3 months were randomized (1:1) to either continue 3TC/ABC or switch to FTC/TDF, with PI/r unchanged. Subjects were stratified by PI/r (LPV/r vs. other) and comorbidities (CV disease, DM, hyperlipidemias). Primary endpoint was time to loss of virologic response (TLOVR, premature discontinuation, or ARV modification = failure). Fasting lipid profile and 10 year Framingham scores were evaluated at baseline and every 12 weeks though Week 48.

    Results: 311 subjects were treated (FTC/TDF 155, 3TC/ABC 156). Overall, baseline characteristics were similar between arms: 85% males, 28% African Americans, median age 46 years, 72% with comorbidities, and 47% taking lipid-lowering agents. There were no differences in early discontinuation rates (11%) and adverse events between arms. Through Week 48, FTC/TDF was non-inferior to 3TC/ABC by TLOVR (86.5% vs 83.3% HIV RNA <200 copies/mL), with lower rate of VF for FTC/TDF vs 3TC/ABC (2% vs 8%; p=0.033). At Week 48, FTC/TDF compared to 3TC/ABC showed greater declines in fasting LDL (median change -7 vs 2 mg/dL; p=0.007), TC (-21 vs -3 mg/dL; p<0.001), and TG (-18 vs -9 mg/dL; p=0.074) with significant declines in LDL and TC beginning at Week 12. According to NCEP thresholds, subjects who switched to FTC/TDF had improved TC (p=0.004) and TG (p=0<0.001); 61.5% on FTC/TDF vs 44.6% on 3TC/ABC had TC<200mg/dL and 55.6% vs. 41.0% had TG<150mg/dL. Mean (SD) change in 10 year Framingham scores were ‑1.2 (4.4) and ‑0.3 (4.0) for FTC/TDF vs 3TC/ABC (between arms p=0.22; within arms p=0.006 for FTC/TDF and p=0.40 for 3TC/ABC).

    Conclusion: In older HIV+ population with comorbidities, switching subjects from 3TC/ABC to FTC/TDF maintained virologic suppression with improved lipid parameters and Framingham scores.

    Subject Category: H. HIV/AIDS and other retroviruses

    Edwin DeJesus, MD, FACP1, Rafael Campo, MD2, Fritz Bredeek, MD, PhD, FACP3, Hui Wang, MS Biometrics4, Lauren Dau, PharmD4, John Flaherty, PharmD4 and Todd Fralich, MD4, (1)Orlando Immunology Center, Orlando, FL, (2)University of Miami, Miami, FL, (3)Metropolis Medical, San Francisco, CA, (4)Gilead Sciences, Foster City, CA


    E. DeJesus, Merck: Consultant and Speaker's Bureau, Research support and Speaker honorarium
    Bristol-Myers Squibb: Consultant and Speaker's Bureau, Research support and Speaker honorarium
    Gilead Sciences: Consultant and Speaker's Bureau, Research support and Speaker honorarium
    GlaxoSmithKline: Investigator and Speaker's Bureau, Research support and Speaker honorarium
    Tibotec: Investigator and Speaker's Bureau, Research support and Speaker honorarium
    Pfizer: , Research support
    Hoffman LaRoche: , Research support
    Achillion: , Research support
    Avexa: , Research support
    Taimed: , Research support

    R. Campo, Gilead Sciences: Grant Investigator and Scientific Advisor, Consulting fee and Grant recipient
    Pfizer: Grant Investigator, Grant recipient
    Tibotec: Scientific Advisor, Consulting fee
    Merck: Grant Investigator, Scientific Advisor and Wife is an employee and stockholder , Consulting fee, Grant recipient and Wife received salary and stock

    F. Bredeek, Merck: Research Contractor, Scientific Advisor and Speaker's Bureau, Research support and Speaker honorarium
    Gilead: Research Contractor and Speaker's Bureau, Research support and Speaker honorarium

    H. Wang, Gilead Sciences: Employee, Salary

    L. Dau, Gilead Sciences: Employee, Salary

    J. Flaherty, Gilead Sciences: Employee, Salary

    T. Fralich, Todd Fralich: Employee, Salary

    Findings in the abstracts are embargoed until 12:01 a.m. EST Thursday, Oct. 20 with the exception of research findings presented at IDSA press conferences.