HIV and Bone Disease: Through Thick and Thin! Pablo Tebas, MD

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2 HIV and Bone Disease: Through Thick and Thin! Pablo Tebas, MD April 30 th, 2016

3 Disclosures I serve in an adjudication panel in a VZV vaccine study (Glaxo) I consult for Merck My research is supported indirectly (through Penn) by all the manufacturers of HIV drugs I do not give non CME talks 3

4 Objectives To describe the epidemiology, and pathogenesis of osteoporosis in HIV-infected persons To review recent advances in our understanding of HIV infection and bone disease To identify which HIV-infected patients should be screened for osteoporosis. To recognize the secondary causes of bone loss that should be evaluated. To describe the optimal treatment strategy for the prevention and treatment of bone disease in HIV-infected persons. 4

5 Outline What do we know? What have we learn in the last couple of years? What can we do about bone disease and HIV? 5

6 What do we know?

7 #1. Both osteopenia and osteoporosis are very common in the HIV+ population Osteoporosis Brown T, Qaqish R. AIDS. 2006; 20:

8 #2. HIV by itself is associated with osteopenia and osteoporosis Baseline characteristics. ACTG 5224s. Antiretroviral naïve individuals N=269 * Age, median (IQR) 38 (31,44) Male (%) 85% White non-hispanic Race (%) 47% HIV RNA log 10 c/ml, median (IQR) 4.62 (4.24,4.90) HIV RNA 100,000 c/ml (%) 41% CD4 cells/mm 3, median (IQR) 233 (106,334) CD4 < 200 cells/mm 3 (%) 43% Lumbar spine T score -1 (%) 35% BMI, Median (IQR) 24.9 (21.8, 28.2) Limb fat kg, Median (IQR) 7.4 (4.7,10.1) Baseline prevalence of osteopenia/osteoporosis 35% McComsey G, et al. J Infect Dis. (2011) 203(12):

9 # 3. When we start antiretroviral therapy patients lose bone. Independently of the regimen. Some drugs more than others * * * -linear regression No significant interaction of NRTI and NNRTI/PI components (p=0.63) A5224s McComsey G, et al. J Infect Dis. (2011) 203(12):

10 #4. Some people lose more bone than others Patients with lower CD4s lose more bone Philip Grant et al. Clin Infect Dis. (2013) 57 (10):

11 Predictors of initial bone loss Patients with higher viral loads and with more improvement in CD4s lose more bone Philip Grant et al. Clin Infect Dis. (2013) 57 (10):

12 #5. Starting antiretrovirals induces a state of rapid bone turnover Tebas et al. AIDS. 29(18): , November 28,

13 #6. This problem is clinically relevant. Patients with HIV have more fractures than non HIV patients Triant, VA, et al. J Clin Endocrinol Metab. 2008;93:

14 #7. The rate of fractures has increased in the HAART era The VA cohort study Pre-HAART Era: 1.61 Events/1000 PY HAART HAART ERAEra: 4.09 Events/1000 PY Bedimo R, et al. Risk of Osteoporotic Fractures Associated with Cumulative Exposure to Tenofovir and Other Antiretroviral Agents. IAS

15 #8. Tenofovir and boosted PIs are associated with an increased the risk of fracture Hazard ratio TDF TDF1 TDF2 ABC ABC1 ABC2 AZT/D4T AZT/D4T1 AZT/D4T2 NNRTI NNRTI1 NNRTI2 rpi rpi1 rpi2 MV Model 1: Controlling for CKD, age, race, tobacco use, diabetes and BMI; MV Model 2: Controlling for Model 1 variables + concomitant exposure to other ARVs. Bedimo et al. AIDS

16 What have we learned lately?

17 #1. The pathogenic mechanism is probably immune reconstitution (plus bone toxicity of tenofovir) What they did: transplant T cells into immunocompromised mice to mimic ART-induced T-cell expansion What they saw: Bone loss associated with the reconstitution Ofotokum et al. Nature Communications

18 #2. It can be partially prevented with vitamin D and Ca ++ Overton et al. Annals of Internal Medicine. 162(12): , June 16,

19 #3. It can be prevented with a single dose of zoledronic acid Ofotokun I et al. CROI 2016 Feb Boston 19

20 Should we do any of those? Not yet* * My opinion 20

21 #4. Tenofovir does something to your bones independently of HIV (and looks reversible) Grant R, et al. CROI Abstract 48LB. 21

22 TAF is more bone friendly than TDF (naive) GS : Change in BMD BMD decline > 5 % E/C/F/TAF: 10% spine; 7% hip E/C/F/TDF: 22% spine; 19% hip Fractures E/C/F/TAF: 7 (0.8%) E/C/F/TDF: 12 (1.4%) Sax et al. Lancet 2015; Genvoya PI

23 TAF is more bone friendly than TDF (switch) Gallant et al. Lancet HIV

24 How clinically important is that 1% Lets say that you are 54 and your BMD is 1 g/cm2 (normal) Your risk of a major fracture in 10 years is 4.7% Lets make your bones 2% better, your BMD is 1.02 g/cm2 (normal) Your risk of a major fracture in 10 years is 4.6% Not much for most people 24

25 Should we start/switch everybody to TAF? Not yet* * My opinion 25

26 Cost implications Using cost-effectiveness methods, we find that current conditions warrant an annual premium of up to $1000 over the average wholesale price (AWP) of TDF. Once generic coformulations of tenofovir/lamivudine become accessible, however, the appropriate premium for TAF will likely merit a downward adjustment Walensky et al. CID

27 What do you do with your patient?

28 Approach to bone problems in HIV patients CID 2010; 51(8):

29 What next? CID 2010; 51(8):

30 Secondary causes of low BMD Conditions Vitamin D deficiency Lab Test 25-hydroxyvitamin D Hyperparathyroidism ipth, Ca, PO 4 Renal phosphate wasting in pts Fractional excretion of on TDF phosphate Subclinical hyperthyroidism Hypogonadism Idiopathic hypercalciuria TSH Morning free testosterone, menstrual history, FSH 24-hr urinary calcium National Osteoporosis Foundation. 30

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32 US NOF Guidelines 2008: Who to Treat* Those with hip or vertebral fractures Those with BMD T-scores -2.5 at the femoral neck, total hip, or spine by DXA Those with T-score b/t -1 and -2.5 (osteopenia) at above sites AND 10-year hip fracture probability 3% or 10-year all major osteoporosis-related fracture 20% based on FRAX model *applies to post-menopausal women and men 50 years Very few people with HIV* * Not an opinion, a fact 32

33 #6. Alendronate appears to be the best treatment for osteoporosis in patients with HIV Results: Change in lumbar BMD % change from baseline * significant within arms significant between arms Vit D + Ca+ Alendronate Vit D + Ca * Weeks Lumbar Spine * Mondy et al. J Acquir Immune Defic Syndr Apr 1;38(4):

34 Do not think bisphosphonates are innocuous The FDA panel wants stronger warning for bone loss drugs Wall Street Journal September 21,

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