As
previously reported, the ARTEN trial included 569 treatment-naive patients
who were randomly assigned to receive 300/100 mg once-daily (QD) atazanavir/ritonavir,
or nevirapine administered either 200 mg twice-daily (BID) or 400 mg once-daily,
each in combination with the fixed-dose
once-daily tenofovir/emtricitabine combination pill (Truvada). At 48 weeks,
66.8% of patients who received nevirapine achieved viral load < 50 copies/mL
on 2 consecutive tests, compared with 64.8% of those who received atazanavir/ritonavir.
In
the sub-analysis presented last week, investigators analyzed early viral decay,
percentage of patients with HIV RNA < 50 copies/mL at each visit, and CD4 cell
count increases within the first 12 weeks of treatment.
Time
to treatment response (TTR) was defined as time from the start of treatment until
the first measurement of the first confirmed virological response.
Results
 | 62.8%
of of 376 patients in the combined (200 and 400 mg) nevirapine arm and 65.8% of
the 193 patients in the atazanavir/ritonavir arm had viral load > 100,000 copies/mL
at baseline. |
| At
8 weeks, 26.3% of patients taking nevirapine and 23.8% of those taking atazanavir/ritonavir
achieved vial load < 50 copies/mL |
| At
12 weels, the corresponding percentages were 44.2% and 39.4%, respectively. |
| Distributions
of TTR were significantly better for nevirapine than for atazanavir/ritonavir. |
Table:
Early virological and immunological response
Parameter | Nevirapine
combined | Atazanavir/
ritonavir | ANCOVA |
| Mean
HIV-RNA (log10) (SD) Baseline | 5.12
(0.64) | 5.12
(0.66) |
|
Change
from baseline at Week 4
(log10) (SD) | -2.32
(0.58) | -2.16
(0.53) | P=0.004 |
Change
from baseline at Week 12
(log10) (SD) | -2.98
(0.83) | 2.94
(0.64) |
Non-significant |
| Mean
CD4 cell count (SD) Baseline | 193
(95) | 193
(96) |
|
| Change
from baseline at Week 4 (SD) | +78
(94) | +86
(94) |
Non-significant |
| Change
from baseline at Week 12 (SD) | +121
(113) | +114
(117) |
Non-significant |
Conclusions
| Nevirapine
and atazanavir/ritonavir, both combined with fixed-dose tenofovir/emtricitabine,
led to comparable virological and immunological responses. |
| However,
viral load decay within the first 4 weeks and time to treatment response were
significantly better for nevirapine. |
| Non-inferiority
between nevirapine and atazanavir/ritonavir (both combined with tenofovir/emtricitabine)
with regard to treatment response at week 48 was established. |
| The
ARTEN study confirms that the combination of nevirapine and tenofovir/emtricitabine
is effective in treatment-naive patients, including those with high viral load
at baseline. |
| The
study demonstrates that nevirapine is an effective and well tolerated drug for
first-line therapy, when used in accordance with the guideline-recommended CD4
cell count thresholds for nevirapine of < 250 cells/mm3 for women and <
400 cells/mm3 for men. |
For
more information about this study, see
the poster presented at ICAAC.
Royal
Free Hospital, London, UK; Hosp. Carlos III, Madrid, Spain; Ruhr-Univ. Bochum,
Bochum, Germany; St Mary's Hosp., London, UK; Boehringer Ingelheim, Ingelheim,
Germany.
9/22/09
Reference
M
Johnson, V Soriano, N. Brockmeyer, and others. Early Virological and Immunological
Response is Comparable for Nevirapine and RTV-boosted Atazanavir: An ARTEN Sub-analysis.
49th Interscience Conference on Antimicrobial Agents and Chemotherapy (ICAAC 2009).
San Francisco. September 12-15, 2009. Abstract H-924c.
