Table 2. Genotypic evolution of integrase and phenotypic sensitivity to raltegravir and elvitegravir in 3 patients failing on raltegravir-containing regimens.
| Patient N° | Time on RAL | ART | Viral load (log10copies/ml) | CD4 (cells/mm3) | Integrase mutations | RAL FC | EVG FC |
| 1 | D0 | RAL/ETR/DRV/r | 6.7 | 16 | V72I I203M | 0.89 | 0.89 |
| M1 | RAL/ETR/DRV/r | 5.8 | 20 | V72I N155N/H I203M | 1.07 | 2.1 | |
| M3 | RAL/ETR/DRV/r | 6.3 | 4 | V72I L74L/M T97A/T Y143C I203M | 5.87 | 1.56 | |
| M6 | RAL/ETR/DRV/r | 5.6 | 10 | V72I L74L/M T97A/T Y143C/Y I203M | n.d. | n.d. | |
| M9 | ETR/DRV/r* | 5.7 | 10 | V72I I203M | 0.98 | 0.83 | |
| M12 | ETR/DRV/r* | 5.5 | 7 | V72I I203M | 0.76 | 1.43 | |
| 2 | D0 | RAL/ETR/DRV/r/ENF | 6.4 | 36 | V151I/V | 0.76 | 0.94 |
| M1 | RAL/ETR/DRV/r/ENF | 5.2 | 77 | n.d. | n.d. | n.d. | |
| M3 | RAL/ETR/DRV/r/ENF | 5.4 | 67 | N155N/H | 1.72 | 6.05 | |
| M6 | RAL/ETR/DRV/r/ENF | 4.8 | 36 | T97A/T G163G/R Y143Y/C/H/R | 28.52 | 6.23 | |
| M9 | RAL/ETR/DRV/r/ENF | 5.6 | 31 | T97A/T G163G/R Y143Y/C/H/R | 21.13 | 2.68 | |
| M12 | RAL/ETR/DRV/r/ENF | 5.5 | 12 | L74L/M T97A/T G163G/R Y143Y/C/H/R V201I/V | n.d. | n.d. | |
| 3 | D0 | RAL/TDF/FTC/ETR/DRV/r | 5.6 | 22 | V72I | 0.91 | 0.60 |
| M1 | RAL/TDF/FTC/ETR/DRV/r | 4.7 | 48 | V72I | n.d. | n.d. | |
| M3 | RAL/TDF/FTC/ETR/DRV/r | 4.5 | 88 | V72I N155N/H | n.d. | n.d. | |
| M6 | RAL/TDF/FTC/ETR/DRV/r | 5.6 | 103 | V72I T97A/T Y143C/H/R/Y | 51.95 | 3 | |
| M12 | RAL/TDF/FTC/ETR/DRV/r | 6.2 | 69 | V72I T97A/T Y143C/H/R/Y | n.d. | 9.57 |
Abbreviations: Time on RAL: duration of raltegravir–based therapy (months); *: raltegravir has been removed from therapy after month 6 for patient 1; RAL FC: raltegravir sensitivity fold-change; EVG FC: elvitegravir sensitivity fold-change; TDF: tenofovir diphospho fumarate; ETR: etravirine; DRV/r: darunavir boosted with ritonavir; ENF: enfuvirtide; FTC: emtricitabine; n.d.: not determined.