CNA30024 was a multicenter, double-blind, controlled trial in which 649 HIV-1–infected, therapy-naive adults were randomized and received either abacavir (300 mg twice daily), lamivudine (150 mg twice daily), and efavirenz (600 mg once daily); or zidovudine (300 mg twice daily), lamivudine (150 mg twice daily), and efavirenz (600 mg once daily). The duration of double-blind treatment was at least 48 weeks. Trial participants were male (81%), white (51%), black (21%), and Hispanic (26%). The median age was 35 years; the median pretreatment CD4+ cell count was 264 cells per mm
3, and median plasma HIV-1 RNA was 4.79 log
10 copies per mL. The outcomes of randomized treatment are provided in Table 7.
Table 7. Outcomes of Randomized Treatment through Week 48 (CNA30024)Outcome | Abacavir plus Lamivudine plus Efavirenz (n = 324) | Zidovudine plus Lamivudine plus Efavirenz (n = 325) |
Responder
| 69% (73%) | 69% (71%) |
Virologic failure
| 6% | 4% |
Discontinued due to adverse reactions | 14% | 16% |
Discontinued due to other reasons
| 10% | 11% |
After 48 weeks of therapy, the median CD4+ cell count increases from baseline were 209 cells per mm
3 in the group receiving abacavir and 155 cells per mm
3 in the zidovudine group. Through Week 48, 8 subjects (2%) in the group receiving abacavir (5 CDC classification C events and 3 deaths) and 5 subjects (2%) on the zidovudine arm (3 CDC classification C events and 2 deaths) experienced clinical disease progression.
CNA3005 was a multicenter, double-blind, controlled trial in which 562 HIV-1–infected, therapy-naive adults were randomized to receive either abacavir (300 mg twice daily) plus COMBIVIR
® (lamivudine 150 mg/zidovudine 300 mg twice daily), or indinavir (800 mg 3 times a day) plus COMBIVIR twice daily. The trial was stratified at randomization by pre-entry plasma HIV-1 RNA 10,000 to 100,000 copies per mL and plasma HIV-1 RNA greater than 100,000 copies per mL. Trial participants were male (87%), white (73%), black (15%), and Hispanic (9%). At baseline the median age was 36 years; the median baseline CD4+ cell count was 360 cells per mm
3, and median baseline plasma HIV-1 RNA was 4.8 log
10 copies per mL. Proportions of subjects with plasma HIV-1 RNA less than 400 copies per mL (using Roche AMPLICOR HIV-1 MONITOR Test) through 48 weeks of treatment are summarized in Table 8.
Table 8. Outcomes of Randomized Treatment through Week 48 (CNA3005)Outcome | Abacavir plus Lamivudine/Zidovudine (n = 262) | Indinavir plus Lamivudine/Zidovudine (n = 265) |
Responder
| 49% | 50% |
Virologic failure
| 31% | 28% |
Discontinued due to adverse reactions | 10% | 12% |
Discontinued due to other reasons
| 11% | 10% |
Treatment response by plasma HIV-1 RNA strata is shown in Table 9.
Table 9. Proportions of Responders through Week 48 by Screening Plasma HIV-1 RNA Levels (CNA3005)Screening HIV-1 RNA (copies/mL) | Abacavir plus Lamivudine/Zidovudine (n = 262) | Indinavir plus Lamivudine/Zidovudine (n = 265) |
< 400 copies/mL | n | < 400 copies/mL | n |
≥ 10,000 - ≤ 100,000 | 50% | 166 | 48% | 165 |
> 100,000 | 48% | 96 | 52% | 100 |
In subjects with baseline viral load greater than 100,000 copies per mL, percentages of subjects with HIV-1 RNA levels less than 50 copies per mL were 31% in the group receiving abacavir versus 45% in the group receiving indinavir.
Through Week 48, an overall mean increase in CD4+ cell count of about 150 cells per mm
3 was observed in both treatment arms. Through Week 48, 9 subjects (3.4%) in the group receiving abacavir (6 CDC classification C events and 3 deaths) and 3 subjects (1.5%) in the group receiving indinavir (2 CDC classification C events and 1 death) experienced clinical disease progression.
CNA30021 was an international, multicenter, double-blind, controlled trial in which 770 HIV-1–infected, therapy-naive adults were randomized and received either abacavir 600 mg once daily or abacavir 300 mg twice daily, both in combination with lamivudine 300 mg once daily and efavirenz 600 mg once daily. The double-blind treatment duration was at least 48 weeks. Trial participants had a mean age of 37 years; were male (81%), white (54%), black (27%), and American Hispanic (15%). The median baseline CD4+ cell count was 262 cells per mm
3 (range: 21 to 918 cells per mm
3) and the median baseline plasma HIV-1 RNA was 4.89 log
10 copies per mL (range: 2.60 to 6.99 log
10 copies per mL).
The outcomes of randomized treatment are provided in Table 10.
Table 10. Outcomes of Randomized Treatment through Week 48 (CNA30021)Outcome | Abacavir 600 mg q.d. plus EPIVIR
® plus Efavirenz
(n = 384) | Abacavir 300 mg b.i.d. plus EPIVIR plus Efavirenz (n = 386) |
Responder
| 64% (71%) | 65% (72%) |
Virologic failure
| 11% (5%) | 11% (5%) |
Discontinued due to adverse reactions | 13% | 11% |
Discontinued due to other reasons
| 11% | 13% |
After 48 weeks of therapy, the median CD4+ cell count increases from baseline were 188 cells per mm
3 in the group receiving abacavir 600 mg once daily and 200 cells per mm
3 in the group receiving abacavir 300 mg twice daily. Through Week 48, 6 subjects (2%) in the group receiving abacavir 600 mg once daily (4 CDC classification C events and 2 deaths) and 10 subjects (3%) in the group receiving abacavir 300 mg twice daily (7 CDC classification C events and 3 deaths) experienced clinical disease progression. None of the deaths were attributed to trial medications.