Table 2.
Etonogestrel and ethinyl estradiol plasma pharmacokinetic parameters after release from a vaginal ring contraceptive device over 21 days
| Pharmacokinetic parameter | Group | N |
Median (IQR) |
Geometric Mean (95% CI) |
Geometric Mean Ratio (90% CI) |
Wilcoxon rank–sum p–value |
| Day 7 concentration (pg/mL) | Control (no ART) | 24 | 1,970 (1,310 – 2,400) | 1,774 (1,504 – 2,092) | ||
| Efavirenz | 25 | 427 (282 – 509) | 343 (267 – 437) | 0·19 (0·15 – 0·25) | <0·0001 | |
| Atazanavir/ ritonavir | 24 | 3,250 (2,480 – 4,040) | 3,065 (2,631 – 3,571) | 1·73 (1·44 – 2·07) | <0·0001 | |
| Day 14 concentration (pg/mL) | Control (no ART) | 23 | 2,070 (1,600 – 2,620) | 1,876 (1,557 – 2,262) | ||
| Efavirenz | 25 | 437 (292 – 550) | 371 (286 – 481) | 0·20 (0·15 – 0·26) | <0·0001 | |
| Atazanavir/ ritonavir | 24 | 3,530 (2,950 – 4,360) | 3,369 (2,817 – 4,030) | 1·80 (1·46 – 2·22) | <0·0001 | |
| Day 21 concentration (pg/mL) | Control (no ART) | 25 | 1,860 (1,530 – 2,330) | 1,812 (1,509 – 2,178) | ||
| Efavirenz | 25 | 429 (311 – 577) | 381 (288 – 503) | 0·21 (0·16 – 0·28) | <0·0001 | |
| Atazanavir/ ritonavir | 24 | 3,290 (2,690 – 3,900) | 3,105 (2,539 – 3,798) | 1·71 (1·37 – 2·14) | <0·0001 | |
| AUC0–21days (pg*week/mL)a | Control (no ART) | 23 | 33,600 (23,404 – 42,085) | 31,687 (26,687 – 37,624) | ||
| Efavirenz | 25 | 7,724 (5,251 – 9,064) | 6,503 (5,096 – 8,297) | 0·21 (0·16 – 0·26) | <0·0001 | |
| Atazanavir/ ritonavir | 24 | 58,745 (52,881 – 73,665) | 56,790 (48,604 – 66,354) | 1·79 (1·49 – 2·16) | <0·0001 | |
| Pharmacokinetic parameter | Group | N |
Median (IQR) |
Geometric Mean (95% CI) |
Geometric Mean Ratio (90% CI) |
Wilcoxon rank–sum p–value |
| Day 7 concentration (pg/mL) | Control (no ART) | 24 | 18 (13 – 31) | 20 (16 – 25) | ||
| Efavirenz | 25 | 10 (7 – 13) | 9 (7 – 11) | 0·44 (0·34 – 0·58) | <0·0001 | |
| Atazanavir/ ritonavir | 24 | 16 (11 – 19) | 14 (12 – 17) | 0·72 (0·58 – 0·91) | 0·066 | |
| Day 14 concentration (pg/mL) | Control (no ART) | 23 | 20 (16 – 28) | 21 (17 – 25) | ||
| Efavirenz | 25 | 11 (8 – 13) | 9 (7 – 11) | 0·42 (0·32 – 0·55) | <0·0001 | |
| Atazanavir/ ritonavir | 24 | 17 (11 – 21) | 15 (13 – 18) | 0·74 (0·59 – 0·91) | 0·032 | |
| Day 21 concentration (pg/mL) | Control (no ART) | 25 | 21 (16 – 30) | 22 (18 – 26) | ||
| Efavirenz | 25 | 11 (7 – 13) | 9 (7 – 11) | 0·41 (0·32 – 0·52) | <0·0001 | |
| Atazanavir/ ritonavir | 24 | 16 (10 – 20) | 14 (11 – 17) | 0·62 (0·49 – 0·79) | 0·0037 | |
| AUC0–21days (pg*week/mL)a | Control (no ART) | 23 | 324 (252 – 524) | 352 (287 – 433) | ||
| Efavirenz | 25 | 188 (146 – 227) | 154 (120 to 199) | 0·44 (0·34 – 0·57) | <0·0001 | |
| Atazanavir/ ritonavir | 24 | 268 (219 – 339) | 259 (221 – 303) | 0·73 (0·60 – 0·91) | 0·036 |
Abbreviations: ART; antiretroviral therapy, AUC, area under the concentration time curve.
a
Estimated value based on trapezoidal rule from Day 0–21 (SAS version 9.4, SAS Institute Inc, Cary, NC, USA)