Clinical Pharmacology for Tivicay
Mechanism Of Action
Dolutegravir is an HIV-1 antiretroviral agent [see Microbiology].
Pharmacodynamics
Effects On Electrocardiogram
In a randomized, placebo-controlled, cross-over trial, 42 healthy subjects received single-dose oral administrations of placebo, dolutegravir 250-mg suspension (exposures approximately 3– fold of the 50-mg once-daily dose at steady state), and moxifloxacin 400 mg (active control) in random sequence. After baseline and placebo adjustment, the maximum mean QTc change based on Fridericia correction method (QTcF) for dolutegravir was 2.4 msec (1-sided 95% upper CI: 4.9 msec). TIVICAY did not prolong the QTc interval over 24 hours postdose.
Effects On Renal Function
The effect of dolutegravir on renal function was evaluated in an open-label, randomized, 3-arm, parallel, placebo-controlled trial in healthy subjects (n = 37) who received dolutegravir 50 mg once daily (n = 12), dolutegravir 50 mg twice daily (n = 13), or placebo once daily (n = 12) for 14 days. A decrease in creatinine clearance, as determined by 24-hour urine collection, was observed with both doses of dolutegravir after 14 days of treatment in subjects who received 50 mg once daily (9% decrease) and 50 mg twice daily (13% decrease). Neither dose of dolutegravir had a significant effect on the actual glomerular filtration rate (determined by the clearance of probe drug, iohexol) or effective renal plasma flow (determined by the clearance of probe drug, para-amino hippurate) compared with the placebo.
Pharmacokinetics
The pharmacokinetic properties of dolutegravir have been evaluated in healthy adult subjects and HIV-1–infected adult subjects. Exposure to dolutegravir was generally similar between healthy subjects and HIV-1–infected subjects. The non-linear exposure of dolutegravir following 50 mg twice daily compared with 50 mg once daily in HIV-1–infected subjects (Table 9) was attributed to the use of metabolic inducers in the background antiretroviral regimens of subjects receiving dolutegravir 50 mg twice daily in clinical trials.
Table 9. Dolutegravir Steady-State Pharmacokinetic Parameter Estimates in HIV-1– Infected Adults
| Parameter |
50 mg Once Daily Geometric Meana (%CV) |
50 mg Twice Daily Geometric Meanb (%CV) |
| AUC(0-24) (mcg·h/mL) |
53.6 (27) |
75.1 (35) |
| Cmax (mcg/mL) |
3.67 (20) |
4.15 (29) |
| Cmin (mcg/mL) |
1.11 (46) |
2.12 (47) |
a Based on population pharmacokinetic analyses using data from SPRING-1 and SPRING-2.
b Based on population pharmacokinetic analyses using data from VIKING (ING112961) and VIKING-3. |
TIVICAY tablets and TIVICAY PD tablets for oral suspension are not bioequivalent. The relative bioavailability of TIVICAY PD is approximately 1.6-fold higher than TIVICAY; therefore, the 2 dosage forms are not substitutable on a milligram-per-milligram basis [see DOSAGE AND ADMINISTRATION].
Absorption
Following oral administration of dolutegravir, peak plasma concentrations were observed 1 to 3 hours postdose. With once-daily dosing, pharmacokinetic steady state is achieved within approximately 5 days with average accumulation ratios for AUC, Cmax, and C24 h ranging from 1.2 to 1.5.
Dolutegravir plasma concentrations increased in a less than dose-proportional manner above 50 mg. Dolutegravir is a P-gp substrate in vitro. The absolute bioavailability of dolutegravir has not been established.
Effect of Food
TIVICAY or TIVICAY PD may be taken with or without food. Food increased the extent of absorption and slowed the rate of absorption of dolutegravir following a 50-mg dose of TIVICAY. Low-, moderate-, and high-fat meals increased dolutegravir AUC(0-∞) by 33%, 41%, and 66%; increased Cmax by 46%, 52%, and 67%; and prolonged Tmax to 3, 4, and 5 hours from 2 hours under fasted conditions, respectively.
Distribution
Dolutegravir is highly bound (greater than or equal to 98.9%) to human plasma proteins based on in vivo data and binding is independent of plasma concentration of dolutegravir. The apparent volume of distribution (Vd/F) following 50-mg once-daily administration is estimated at 17.4 L based on a population pharmacokinetic analysis.
Cerebrospinal Fluid (CSF)
In 12 treatment-naïve subjects on dolutegravir 50 mg daily plus abacavir/lamivudine, the median dolutegravir concentration in CSF was 13.2 ng/mL (range: 3.74 ng/mL to 18.3 ng/mL) 2 to 6 hours postdose after 16 weeks of treatment. The clinical relevance of this finding has not been established.
Elimination
Dolutegravir has a terminal half-life of approximately 14 hours and an apparent clearance (CL/F) of 1.0 L/h based on population pharmacokinetic analyses.
Metabolism
Dolutegravir is primarily metabolized via UGT1A1 with some contribution from CYP3A.
Polymorphisms in Drug-Metabolizing Enzymes
In a meta-analysis of healthy subject trials, subjects with UGT1A1 (n = 7) genotypes conferring poor dolutegravir metabolism had a 32% lower clearance of dolutegravir and 46% higher AUC compared with subjects with genotypes associated with normal metabolism via UGT1A1 (n = 41).
Excretion
After a single oral dose of [14C] dolutegravir, 53% of the total oral dose was excreted unchanged in feces. Thirty-one percent of the total oral dose was excreted in urine, represented by an ether glucuronide of dolutegravir (18.9% of total dose), a metabolite formed by oxidation at the benzylic carbon (3.0% of total dose), and its hydrolytic N-dealkylation product (3.6% of total dose). Renal elimination of unchanged drug was low (less than 1% of the dose).
Specific Populations
Pediatric Patients
The pharmacokinetics of dolutegravir were evaluated in the IMPAACT P1093 trial and in 2 weight-band-based pharmacokinetic substudies from the ODYSSEY trial. Steady-state plasma exposure at doses by weight band are summarized in Table 10 [see Clinical Studies].
Mean dolutegravir AUC0-24h and C24h in HIV-1–infected pediatric subjects were comparable to those in adults after 50 mg once daily or 50 mg twice daily. Mean Cmax is higher in pediatrics, but the increase is not considered clinically significant as the safety profiles were similar in pediatric and adult subjects [see Use In Specific Populations].
Table 10. Summary of Pharmacokinetic Parameters in Pediatric HIV-1–Infected Subjects (Pooled Analyses for IMPAACT P1093 and ODYSSEYa Trials)
| Weight Band |
Doseb of TIVICAY or TIVICAY PD |
n |
Pharmacokinetic Parameter Geometric Mean (%CV) |
Cmax
(mcg/mL) |
AUC0-24h
(mcg·h/mL) |
C24h
(ng/mL) |
| 3 kg to <6 kg |
TIVICAY PD 5 mg once daily |
8 |
3.80 (34) |
49.37 (49) |
962 (98) |
| 6 kg to <10 kg |
TIVICAY PD 15 mg once daily |
17 |
5.27 (50) |
57.17 (76) |
706 (177) |
| 10 kg to <14 kg |
TIVICAY PD 20 mg once daily |
13 |
5.99 (33) |
68.75 (48) |
977 (100) |
| 14 kg to <20 kg |
TIVICAY PD 25 mg once daily |
19 |
5.97 (42) |
58.97 (44) |
725 (75) |
| 20 kg to <25 kg |
TIVICAY PD 30 mg once daily |
9 |
7.16 (26) |
71.53 (26) |
759 (73) |
| ≥20 kg |
TIVICAY 50 mg once daily |
49 |
4.92 (40) |
54.98 (43) |
778 (62) |
a Data from 2 weight-band-based pharmacokinetic substudies in the ODYSSEY trial.
b The bioavailability of TIVICAY PD tablets for oral suspension is ~1.6-fold that of TIVICAY tablets. |
Geriatric Patients
Population pharmacokinetic analysis indicated age had no clinically relevant effect on the pharmacokinetics of dolutegravir.
Patients With Hepatic Impairment
In a trial comparing 8 subjects with moderate hepatic impairment (Child-Pugh Score B) with 8 matched healthy controls, exposure of dolutegravir from a single 50-mg dose was similar between the 2 groups. The effect of severe hepatic impairment (Child-Pugh Score C) on the pharmacokinetics of dolutegravir has not been studied.
Patients With Renal Impairment
In a trial evaluating the pharmacokinetics of a single 50-mg tablet of dolutegravir comparing 8 subjects with severe renal impairment (CrCl less than 30 mL/min) with 8 matched healthy controls, AUC, Cmax, and C24 of dolutegravir were lower by 40%, 23%, and 43%, respectively, compared with those in matched healthy subjects. Population pharmacokinetic analysis using data from SAILING and VIKING-3 trials indicated that mild and moderate renal impairment had no clinically relevant effect on the exposure of dolutegravir. There is inadequate information to recommend appropriate dosing of dolutegravir in patients requiring dialysis.
HBV Or HCV Co-Infected Patients
Population analyses using pooled pharmacokinetic data from adult trials indicated no clinically relevant effect of HCV co-infection on the pharmacokinetics of dolutegravir. There were limited data on HBV co-infection.
Gender And Race
Population analyses using pooled pharmacokinetic data from adult trials indicated gender and race had no clinically relevant effect on the exposure of dolutegravir.
Drug Interaction Studies
Drug interaction trials were performed with TIVICAY and other drugs likely to be coadministered or commonly used as probes for pharmacokinetic interactions. The effects of dolutegravir on the exposure of coadministered drugs are summarized in Table 11 and the effects of coadministered drugs on the exposure of dolutegravir are summarized in Table 12.
Dosing or regimen recommendations as a result of established and other potentially significant drug-drug interactions with TIVICAY are provided in Table 8 [see DOSAGE AND ADMINISTRATION, DRUG INTERACTIONS].
Table 11. Summary of Effect of Dolutegravir on the Pharmacokinetics of Coadministered Drugs
| Coadministered Drug(s) and Dose(s) |
Dose of TIVICAY |
n |
Geometric Mean Ratio (90% CI) of Pharmacokinetic Parameters of Coadministered Drug with/without Dolutegravir
No Effect = 1.00 |
| Cmax |
AUC |
Cτ or C24 |
| Elbasvir |
50 mg single dose |
12 |
0.97
(0.89, 1.05) |
0.97
(0.89, 1.05) |
0.98
(0.93, 1.03) |
| 50 mg once daily |
| Ethinyl estradiol |
50 mg twice daily |
15 |
0.99
(0.91 to 1.08) |
1.03
(0.96 to 1.11) |
1.02
(0.93 to 1.11) |
| 0.035 mg |
| Grazoprevir |
50 mg single dose |
12 |
0.64
(0.44, 0.93) |
0.81
(0.67, 0.97) |
0.86
(0.79, 0.93) |
| 200 mg once daily |
| Metformin |
50 mg once daily |
15a |
1.66
(1.53 to 1.81) |
1.79
(1.65 to 1.93) |
_ |
| 500 mg twice daily |
| Metformin |
50 mg twice daily |
15a |
2.11
(1.91 to 2.33) |
2.45
(2.25 to 2.66) |
_ |
| 500 mg twice daily |
| Methadone |
50 mg twice daily |
11 |
1.00
(0. 94 to 1.06) |
0.98
(0.91 to 1.06) |
0.99
(0.91 to 1.07) |
| 16 to 150 mg |
| Midazolam |
25 mg once daily |
10 |
_ |
0.95
(0.79 to 1.15) |
_ |
| 3 mg |
| Norelgestromin |
50 mg twice daily |
15 |
0.89
(0.82 to 0.97) |
0.98
(0.91 to 1.04) |
0.93
(0.85 to 1.03) |
| 0.25 mg |
| Rilpivirine |
50 mg once daily |
16 |
1.10
(0.99 to 1.22) |
1.06
(0.98 to 1.16) |
1.21
(1.07 to 1.38) |
| 25 mg once daily |
| Sofosbuvir |
50 mg once daily |
24 |
0.88
(0.80, 0.98) |
0.92
(0.85, 0.99) |
NA |
| 400 mg once daily Metabolite(GS-331007) |
1.01
(0.93, 1.10) |
0.99
(0.97, 1.01) |
0.99
(0.97, 1.01) |
| Tenofovir disoproxil fumarate |
50 mg once daily |
15 |
1.09
(0.97 to 1.23) |
1.12
(1.01 to 1.24) |
1.12
(1.01 to 1.24) |
| 300 mg once daily |
| Velpatasvir |
50 mg once daily |
24 |
0.94 (0.86, 1.02) |
0.91 (0.84, 0.98) |
0.88 (0.82, 0.94) |
| 100 mg once daily |
| a The number of subjects represents the maximum number of subjects that were evaluated. |
Table 12. Summary of Effect of Coadministered Drugs on the Pharmacokinetics of Dolutegravir
| Coadministered Drug(s) and Dose(s) |
Dose of TIVICAY |
n |
Geometric Mean Ratio (90% CI) of Dolutegravir Pharmacokinetic Parameters with/without Coadministered Drugs
No Effect = 1.00 |
| Cmax |
AUC |
Cτ or C24 |
| Atazanavir |
30 mg once daily |
12 |
1.50
(1.40 to 1.59) |
1.91
(1.80 to 2.03) |
2.80
(2.52 to 3.11) |
| 400 mg once daily |
| Atazanavir/ritonavir |
30 mg once daily |
12 |
1.34
(1.25 to 1.42) |
1.62
(1.50 to 1.74) |
2.21
(1.97 to 2.47) |
| 300/100 mg once daily |
| Darunavir/ritonavir |
30 mg once daily |
15 |
0.89
(0.83 to 0.97) |
0.78
(0.72 to 0.85) |
0.62
(0.56 to 0.69) |
| 600/100 mg twice daily |
| Efavirenz |
50 mg once daily |
12 |
0.61
(0.51 to 0.73) |
0.43
(0.35 to 0.54) |
0.25
(0.18 to 0.34) |
| 600 mg once daily |
| Elbasvir/grazoprevir |
50 mg single dose |
12 |
1.22
(1.05, 1.40) |
1.16
(1.00, 1.34) |
1.14
(0.95, 1.36) |
| 50/200 mg once daily |
| Etravirine |
50 mg once daily |
16 |
0.48
(0.43 to 0.54) |
0.29
(0.26 to 0.34) |
0.12
(0.09 to 0.16) |
| 200 mg twice daily |
| Etravirine + darunavir/ritonavir |
50 mg once daily |
9 |
0.88
(0.78 to 1.00) |
0.75
(0.69 to 0.81) |
0.63
(0.52 to 0.76) |
| 200 mg + 600/100 mg twice daily |
| Etravirine + lopinavir/ritonavir |
50 mg once daily |
8 |
1.07
(1.02 to 1.13) |
1.11
(1.02 to 1.20) |
1.28
(1.13 to 1.45) |
| 200 mg + 400/100 mg twice daily |
| Fosamprenavir/ritonavir |
50 mg once daily |
12 |
0.76
(0.63 to 0.92) |
0.65
(0.54 to 0.78) |
0.51
(0.41 to 0.63) |
| 700 mg/100 mg twice daily |
| Lopinavir/ritonavir |
30 mg once daily |
15 |
1.00
(0.94 to 1.07) |
0.97
(0.91 to 1.04) |
0.97
(0.91 to 1.04) |
| 400/100 mg twice daily |
| Rilpivirine |
50 mg once daily |
16 |
1.13
(1.06 to 1.21) |
1.12
(1.05 to 1.19) |
1.22
(1.15 to 1.30) |
| 25 mg once daily |
| Tenofovir |
50 mg once daily |
15 |
0.97
(0.87 to 1.08) |
1.01
(0.91 to 1.11) |
0.92
(0.82 to 1.04) |
| 300 mg once daily |
| Tipranavir/ritonavir |
50 mg once daily |
14 |
0.54
(0.50 to 0.57) |
0.41
(0.38 to 0.44) |
0.24
(0.21 to 0.27) |
| 500/200 mg twice daily |
| Antacid (MAALOX) |
50 mg single dose |
16 |
0.28
(0.23 to 0.33) |
0.26
(0.22 to 0.32) |
0.26
(0.21 to 0.31) |
| simultaneous administration |
| Antacid (MAALOX) |
50 mg single dose |
16 |
0.82
(0.69 to 0.98) |
0.74
(0.62 to 0.90) |
0.70
(0.58 to 0.85) |
| 2 h after dolutegravir |
| Calcium carbonate 1,200 mg |
50 mg single dose |
12 |
0.63
(0.50 to 0.81) |
0.61
(0.47 to 0.80) |
0.61
(0.47 to 0.80) |
| simultaneous administration (fasted) |
| Calcium carbonate 1,200 mg |
50 mg single dose |
11 |
1.07
(0.83 to 1.38) |
1.09
(0.84 to 1.43) |
1.08
(0.81 to 1.42) |
| simultaneous administration (fed) |
| Calcium carbonate 1,200 mg |
50 mg single dose |
11 |
1.00
(0.78 to 1.29) |
0.94
(0.72 to 1.23) |
0.90
(0.68 to 1.19) |
| 2 h after dolutegravir |
| Carbamazepine |
50 mg once daily |
16a |
0.67
(0.61 to 0.73) |
0.51
(0.48 to 0.55) |
0.27
(0.24 to 0.31) |
| 300 mg twice daily |
| Ferrous fumarate 324 mg |
50 mg single dose |
11 |
0.43
(0.35 to 0.52) |
0.46
(0.38 to 0.56) |
0.44
(0.36 to 0.54) |
| simultaneous administration (fasted) |
| Ferrous fumarate 324 mg |
50 mg single dose |
11 |
1.03
(0.84 to 1.26) |
0.98
(0.81 to 1.20) |
1.00
(0.81 to 1.23) |
| simultaneous administration (fed) |
| Ferrous fumarate 324 mg |
50 mg single dose |
10 |
0.99
(0.81 to 1.21) |
0.95
(0.77 to 1.15) |
0.92
(0.74 to 1.13) |
| 2 h after dolutegravir |
| Multivitamin (One-A-Day) |
50 mg single dose |
16 |
0.65
(0.54 to 0.77) |
0.67
(0.55 to 0.81) |
0.68
(0.56 to 0.82) |
| simultaneous administration |
| Omeprazole |
50 mg single dose |
12 |
0.92
(0.75 to 1.11) |
0.97
(0.78 to 1.20) |
0.95
(0.75 to 1.21) |
| 40 mg once daily |
| Prednisone |
50 mg once daily |
12 |
1.06
(0.99 to 1.14) |
1.11
(1.03 to 1.20) |
1.17
(1.06 to 1.28) |
| 60 mg once daily with taper |
| Rifampinb |
50 mg twice daily |
11 |
0.57
(0.49 to 0.65) |
0.46
(0.38 to 0.55) |
0.28
(0.23 to 0.34) |
| 600 mg once daily |
| Rifampinc |
50 mg twice daily |
11 |
1.18
(1.03 to 1.37) |
1.33
(1.15 to 1.53) |
1.22
(1.01 to 1.48) |
| 600 mg once daily |
| Rifabutin |
50 mg once daily |
9 |
1.16
(0.98 to 1.37) |
0.95
(0.82 to 1.10) |
0.70
(0.57 to 0.87) |
| 300 mg once daily |
a The number of subjects represents the maximum number of subjects that were evaluated.
b Comparison is rifampin taken with dolutegravir 50 mg twice daily compared with dolutegravir 50 mg twice daily.
c Comparison is rifampin taken with dolutegravir 50 mg twice daily compared with dolutegravir 50 mg once daily. |
Microbiology
Mechanism Of Action
Dolutegravir inhibits HIV integrase by binding to the integrase active site and blocking the strand transfer step of retroviral DNA integration which is essential for the HIV replication cycle. Strand transfer biochemical assays using purified HIV-1 integrase and pre-processed substrate DNA resulted in IC50 values of 2.7 nM and 12.6 nM.
Antiviral Activity In Cell Culture
Dolutegravir exhibited antiviral activity against laboratory strains of wild-type HIV-1 with mean EC50 values of 0.5 nM (0.21 ng/mL) to 2.1 nM (0.85 ng/mL) in peripheral blood mononuclear cells (PBMCs) and MT-4 cells. Dolutegravir exhibited antiviral activity against 13 clinically diverse clade B isolates with a mean EC50 value of 0.52 nM in a viral integrase susceptibility assay using the integrase coding region from clinical isolates. Dolutegravir demonstrated antiviral activity in cell culture against a panel of HIV-1 clinical isolates (3 in each group of M clades A, B, C, D, E, F, and G, and 3 in group O) with EC50 values ranging from 0.02 nM to 2.14 nM for HIV-1. Dolutegravir EC50 values against 3 HIV-2 clinical isolates in PBMC assays ranged from 0.09 nM to 0.61 nM.
Antiviral Activity In Combination With Other Antiviral Agents
The antiviral activity of dolutegravir was not antagonistic when combined with the INSTI, raltegravir; non-nucleoside reverse transcriptase inhibitors (NNRTIs), efavirenz or nevirapine; the NRTIs, abacavir or stavudine; the protease inhibitors (PIs), amprenavir or lopinavir; the CCR5 co-receptor antagonist, maraviroc; or the fusion inhibitor, enfuvirtide. Dolutegravir antiviral activity was not antagonistic when combined with the HBV reverse transcriptase inhibitor, adefovir, or inhibited by the antiviral, ribavirin.
Resistance
Cell Culture
Dolutegravir-resistant viruses were selected in cell culture starting from different wild-type HIV-1 strains and clades. Amino acid substitutions E92Q, G118R, S153F or Y, G193E or R263K emerged in different passages and conferred decreased susceptibility to dolutegravir of up to 4-fold. Passage of mutant viruses containing the Q148R or Q148H substitutions selected for additional substitutions in integrase that conferred decreased susceptibility to dolutegravir (fold-change increase of 13 to 46). The additional integrase substitutions included T97A, E138K, G140S, and M154I. Passage of mutant viruses containing both G140S and Q148H selected for L74M, E92Q, and N155H.
Treatment-Naïve Subjects
No subject who received dolutegravir 50-mg once-daily in the treatment-naïve trials SPRING-2 (96 weeks) and SINGLE (144 weeks) had a detectable decrease in susceptibility to dolutegravir or background NRTIs in the resistance analysis subset (n = 12 with HIV-1 RNA greater than 400 copies per mL at failure or last visit and having resistance data). Two virologic failure subjects in SINGLE had treatment-emergent G/D/E193D and G193G/E integrase substitutions at Week 84 and Week 108, respectively, and 1 subject with 275 copies/mL HIV-1 RNA had a treatment-emergent Q157Q/P integrase substitution detected at Week 24. None of these subjects had a corresponding decrease in dolutegravir susceptibility. No treatment-emergent genotypic resistance to the background regimen was observed in the dolutegravir arm in either the SPRING-2 or SINGLE trials. No treatment-emergent primary resistance substitutions were observed in either treatment group in the FLAMINGO trial through Week 96.
Treatment-Experienced, Integrase Strand Transfer Inhibitor-Naïve Subjects
In the dolutegravir arm of the SAILING trial for treatment-experienced and INSTI-naïve subjects (n = 354), treatment-emergent integrase substitutions were observed in 6 of 28 (21%) subjects who had virologic failure and resistance data. In 5 of the 6 subjects’ isolates emergent INSTI substitutions included L74L/M/I, Q95Q/L, V151V/I (n = 1 each), and R263K (n = 2). The change in dolutegravir phenotypic susceptibility for these 5 subject isolates was less than 2-fold. One subject isolate had pre-existing raltegravir resistance substitutions E138A, G140S, and Q148H at baseline and had additional emergent INSTI-resistance substitutions T97A and E138A/T with a corresponding 148-fold reduction in dolutegravir susceptibility at failure. In the comparator raltegravir arm, 21 of 49 (43%) subjects with post-baseline resistance data had evidence of emergent INSTI-resistance substitutions (L74M, E92Q, T97A, E138Q, G140S/A, Y143R/C, Q148H/R, V151I, N155H, E157Q, and G163K/R) and raltegravir phenotypic resistance.
Virologically Suppressed Subjects
SWORD-1 and SWORD-2 are identical trials in virologically suppressed subjects receiving 2 NRTIs plus either an INSTI, an NNRTI, or a PI, that switched to dolutegravir plus rilpivirine (n = 513) or remained on their current antiviral regimen (n = 511). In the pooled SWORD-1 and SWORD-2 trials, 12 subjects (7 in SWORD-1 and 5 in SWORD-2) had confirmed virologic failure (HIV-1 RNA greater than 200 copies/mL) while receiving dolutegravir plus rilpivirine at any time through Week 148. Ten of the confirmed virologic failures had post-baseline resistance data, with 6 isolates showing evidence of rilpivirine resistance, and 2 with evidence of dolutegravir resistance substitutions. Six isolates showed genotypic and/or phenotypic resistance to rilpivirine with emergent NNRTI-resistance substitutions E138E/A (rilpivirine 1.6-fold change), M230M/L (rilpivirine 2-fold change), L100L/I, K101Q, and E138A (rilpivirine 4.1-fold change), K101K/E (rilpivirine 1.2-fold change), K101K/E, M230M/L (rilpivirine 2-fold change), and L100L/V/M, M230M/L (rilpivirine 31-fold change). In addition, 1 virologic failure subject had NNRTI-resistance substitutions K103N and V179I at Week 88 with rilpivirine phenotypic fold change of 5.2 but had no baseline sample.
One virologic failure isolate had emergent INSTI-resistance substitution V151V/I present post-baseline with baseline INSTI-resistance substitutions N155N/H and G163G/R (by exploratory HIV proviral DNA archive sequencing); no integrase phenotypic data were available for this isolate at virologic failure. One other subject had the dolutegravir resistance substitution G193E at baseline and virologic failure, but no detectable phenotypic resistance (fold change = 1.02) at Week 24.
No resistance-associated substitutions were observed for the 2 subjects meeting confirmed virologic failure in the comparative current antiretroviral regimen arms at Week 48.
Treatment-Experienced, Integrase Strand Transfer Inhibitor-Experienced Subjects
VIKING-3 examined the efficacy of dolutegravir 50 mg twice daily plus optimized background therapy in subjects with prior or current virologic failure on an INSTI-(elvitegravir or raltegravir) containing regimen. Use of TIVICAY in INSTI-experienced patients should be guided by the number and type of baseline INSTI substitutions. The efficacy of TIVICAY 50 mg twice daily is reduced in patients with an INSTI-resistance Q148 substitution plus 2 or more additional INSTI30 resistance substitutions, including T66A, L74I/M, E138A/K/T, G140S/A/C, Y143R/C/H, E157Q, G163S/E/K/Q, or G193E/R.
Response By Baseline Genotype
Of the 183 subjects with baseline data, 30% harbored virus with a substitution at Q148, and 33% had no primary INSTI-resistance substitutions (T66A/I/K, E92Q/V, Y143R/C/H, Q148H/R/K, and N155H) at baseline, but had historical genotypic evidence of INSTI-resistance substitutions, phenotypic evidence of elvitegravir or raltegravir resistance, or genotypic evidence of INSTI-resistance substitutions at screening.
Response rates by baseline genotype were analyzed in an “as-treated” analysis at Week 48 (n = 175) (Table 13). The response rate at Week 48 to dolutegravir-containing regimens was 47% (24 of 51) when Q148 substitutions were present at baseline; Q148 was always present with additional INSTI-resistance substitutions (Table 13). In addition, a diminished virologic response of 40% (6 of 15) was observed when the substitution E157Q or K was present at baseline with other INSTI-resistance substitutions but without a Q148H or R substitution.
Table 13. Response by Baseline Integrase Genotype in Subjects with Prior Experience to an Integrase Strand Transfer Inhibitor in VIKING-3
| Baseline Genotype |
Week 48
(<50 copies/mL)
n = 175 |
| Overall Response |
66% (116/175) |
| No Q148 substitutiona |
74% (92/124) |
| Q148H/R + G140S/A/C without additional INSTI-resistance substitutionb |
61% (17/28) |
| Q148H/R + ≥2 INSTI-resistance substitutionsb,c |
29% (6/21) |
INSTI = integrase strand transfer inhibitor.
a Includes INSTI-resistance substitutions Y143R/C/H and N155H.
b INSTI-resistance substitutions included T66A, L74I/M, E138A/K/T, G140S/A/C, Y143R/C/H, E157Q, G163S/E/K/Q, or G193E/R. Two additional subjects had baseline genotypes of Q148Q/R plus L74L/I/M (virologic failure) and Q148R plus E138K (responder).
c The most common pathway with Q148H/R + greater than or equal to 2 INSTI-resistance substitutions had Q148+G140+E138 substitutions (n = 16). |
Response By Baseline Phenotype
Response rates by baseline phenotype were analyzed in an as-treated analysis using all subjects with available baseline phenotypes through Week 48 (n = 163) (Table 14). These baseline phenotypic groups are based on subjects enrolled in VIKING-3 and are not meant to represent definitive clinical susceptibility cut points for dolutegravir. The data are provided to guide clinicians on the likelihood of virologic success based on pretreatment susceptibility to dolutegravir in INSTI-resistant patients.
Table 14. Response by Baseline Dolutegravir Phenotype (Fold-Change from Reference) in Subjects with Prior Experience to an Integrase Strand Transfer Inhibitor in VIKING-3
| Baseline Dolutegravir Phenotype (Fold-Change from Reference) |
Response at Week 48
(<50 copies/mL)
Subset
n = 163 |
| Overall Response |
64% (104/163) |
| <3-fold change |
72% (83/116) |
| 3-<10-fold change |
53% (18/34) |
| ≥10-fold change |
23% (3/13) |
Integrase Strand Transfer Inhibitor Treatment-Emergent Resistance
There were 50 subjects with virologic failure on the dolutegravir twice-daily regimen in VIKING-3 with HIV-1 RNA greater than 400 copies/mL at the failure timepoint, Week 48 or beyond, or the last timepoint on trial. Thirty-nine subjects with virologic failure had resistance data that were used in the Week 48 analysis. In the Week 48 resistance analysis 85% (33 of 39) of the subjects with virologic failure had treatment-emergent INSTI-resistance substitutions in their isolates. The most common treatment-emergent INSTI-resistance substitution was T97A. Other frequently emergent INSTI-resistance substitutions included L74M, I or V, E138K or A, G140S, Q148H, R or K, M154I, or N155H. Substitutions E92Q, Y143R or C/H, S147G, V151A, and E157E/Q each emerged in 1 to 3 subjects’ isolates. At failure, the median dolutegravir fold-change from reference was 61-fold (range: 0.75 to 209) for isolates with emergent INSTI-resistance substitutions (n = 33).
Resistance to one or more background drugs in the dolutegravir twice-daily regimen also emerged in 49% (19 of 39) of subjects in the Week 48 resistance analysis.
In VIKING-4 (ING116529), 30 subjects with current virological failure on an INSTI-containing regimen and genotypic evidence of INSTI-resistance substitutions at screening were randomized to receive either dolutegravir 50 mg twice daily or placebo with the current failing regimen for 7 days and then all subjects received open-label dolutegravir plus optimized background regimen from Day 8. Virologic responses at Week 48 by baseline genotypic and phenotypic INSTI-resistance categories and the INSTI resistance-associated substitutions that emerged on dolutegravir treatment in VIKING-4 were consistent with those seen in VIKING-3.
Cross-Resistance
Site-Directed Integrase Strand Transfer Inhibitor-Resistant Mutant HIV-1 and HIV-2 Strains:
The susceptibility of dolutegravir was tested against 60 INSTI-resistant site-directed mutant HIV-1 viruses (28 with single substitutions and 32 with 2 or more substitutions) and 6 INSTI-resistant site-directed mutant HIV-2 viruses. The single INSTI-resistance substitutions T66K,I151L, and S153Y conferred a greater than 2-fold decrease in dolutegravir susceptibility (range: 2.3-fold to 3.6-fold from reference). Combinations of multiple substitutions T66K/L74M, E92Q/N155H, G140C/Q148R, G140S/Q148H, R or K, Q148R/N155H, T97A/G140S/Q148, and substitutions at E138/G140/Q148 showed a greater than 2-fold decrease in dolutegravir susceptibility (range: 2.5-fold to 21-fold from reference). In HIV-2 mutants, combinations of substitutions A153G/N155H/S163G and E92Q/T97A/N155H/S163D conferred 4-fold decreases in dolutegravir susceptibility, and E92Q/N155H and G140S/Q148R showed 8.5-fold and 17-fold decreases in dolutegravir susceptibility, respectively.
Reverse Transcriptase Inhibitor- and Protease Inhibitor-Resistant Strains
Dolutegravir demonstrated equivalent antiviral activity against 2 NNRTI-resistant, 3 NRTI-resistant, and 2 PI-resistant HIV-1 mutant clones compared with the wild-type strain.
Clinical Studies
Description Of Clinical Studies
The efficacy and safety of TIVICAY or TIVICAY PD were evaluated in the studies summarized in Table 15.
Table 15. Trials Conducted with TIVICAY or TIVICAY PD in HIV-1–Infected Subjects
| Population |
Trial |
Trial Arms |
Timepoint (Week) |
| Adults: |
|
|
|
| Treatmentnaïve |
SPRING-2 (ING113086) (NCT01227824) |
TIVICAY + 2 NRTIs (n = 403)
Raltegravir + 2 NRTIs (n = 405) |
96 |
| SINGLE (ING114467) (NCT01263015) |
TIVICAY + EPZICOM (n = 414)
ATRIPLA (n = 419) |
144 |
| FLAMINGO (ING114915) (NCT01449929) |
TIVICAY + NRTI BR (n = 243) Darunavir/ritonavir + NRTI BR (n = 242) |
96 |
| Treatment- experienced, INSTI-naïve |
SAILING (ING111762) (NCT01231516) |
TIVICAY + BR (n = 354)
Raltegravir + BR (n = 361) |
48 |
| INSTI- experienced |
VIKING-3 (ING112574) (NCT01328041) |
TIVICAY + OBT (n = 183) |
48 |
| Virologically suppressed |
SWORD-1 (NCT02429791) SWORD-2 (NCT02422797) |
Pooled presentation TIVICAY + Rilpivirine (n = 513)
CAR (n = 511) |
48 |
| Pediatrics: |
|
|
|
| 4 weeks and older and weighing at least 3 kg without INSTI resistance |
IMPAACT P1093 (NCT01302847) |
TIVICAY or TIVICAY PD + BR (n = 75) |
24 |
| NRTI = nucleoside reverse transcriptase inhibitor; BR = Background regimen; INSTI = integrase strand transfer inhibitor; OBT = Optimized background therapy; CAR = Current antiretroviral regimen. |
Adult Subjects
Treatment-Naïve Subjects
In SPRING-2, 822 subjects were randomized and received at least 1 dose of either TIVICAY 50 mg once daily or raltegravir 400 mg twice daily, both in combination with fixed-dose dual NRTI treatment (either abacavir sulfate and lamivudine [EPZICOM] or emtricitabine/tenofovir [TRUVADA]). There were 808 subjects included in the efficacy and safety analyses. At baseline, the median age of subjects was 36 years, 13% female, 15% non-white, 11% had hepatitis B and/or C virus co-infection, 2% were CDC Class C (AIDS), 28% had HIV-1 RNA greater than 100,000 copies per mL, 48% had CD4+ cell count less than 350 cells/mm3, and 39% received EPZICOM; these characteristics were similar between treatment groups.
In SINGLE, 833 subjects were randomized and received at least 1 dose of either TIVICAY 50 mg once daily with fixed-dose abacavir sulfate and lamivudine (EPZICOM) or fixed-dose efavirenz/emtricitabine/tenofovir (ATRIPLA). At baseline, the median age of subjects was 35 years, 16% female, 32% non-white, 7% had hepatitis C co-infection (hepatitis B virus co-infection was excluded), 4% were CDC Class C (AIDS), 32% had HIV-1 RNA greater than 100,000 copies/mL, and 53% had CD4+ cell count less than 350 cells/mm3; these characteristics were similar between treatment groups.
Outcomes for SPRING-2 (Week 96 analysis) and SINGLE (Week 144 open-label phase analysis which followed the Week 96 double-blind phase) are provided in Table 16. Side-by-side tabulation is to simplify presentation; direct comparisons across trials should not be made due to differing trial designs.
Table 16. Virologic Outcomes of Randomized Treatment in SPRING-2 at Week 96 and SINGLE at Week 144 (Snapshot Algorithm)
|
SPRING-2
Week 96 |
SINGLE
Week 144 |
TIVICAY 50 mg Once Daily + 2 NRTIs
(n = 403) |
Raltegravir 400 mg Twice Daily + 2 NRTIs
(n = 405) |
TIVICAY 50 mg + EPZICOM Once Daily
(n = 414) |
ATRIPLA Once Daily
(n = 419) |
| HIV-1 RNA <50 copies/mL |
82% |
78% |
71% |
63% |
| Treatment differencea |
4.9% (95% CI: -0.6%, 10.3%)b |
8.3% (95% CI: 2.0%, 14.6%)c |
| Virologic nonresponse |
5% |
10% |
10% |
7% |
| Data in window not <50 copies/mL |
1% |
3% |
4% |
<1% |
| Discontinued for lack of efficacy |
2% |
3% |
3% |
3% |
| Discontinued for other reasons while not suppressed |
<1% |
3% |
3% |
4% |
| Change in ART regimen |
<1% |
<1% |
0 |
0 |
| No virologic data Reasons |
12% |
12% |
18% |
30% |
| Discontinued study/study drug due to adverse event or deathd |
2% |
2% |
4% |
14% |
| Discontinued study/study drug for other reasonse |
8% |
9% |
12% |
13% |
| Missing data during window but on study |
2% |
<1% |
2% |
3% |
| Proportion (%) of Subjects with HIV-1 RNA <50 copies/mL by Baseline Category |
| Plasma viral load (copies/mL) |
|
|
|
|
| ≤100,000 |
84% |
83% |
73% |
64% |
| >100,000 |
79% |
63% |
69% |
61% |
| Gender |
|
|
|
|
| Male |
84% |
79% |
72% |
66% |
| Female |
70% |
68% |
69% |
48% |
| Race |
|
|
|
|
| White |
83% |
78% |
72% |
71% |
| AfricanAmerican/African Heritage/Other |
77% |
75% |
71% |
47% |
NRTI = Nucleoside reverse transcriptase inhibitor.
a Adjusted for pre-specified stratification factors.
b The primary endpoint was assessed at Week 48 and the virologic success rate was 88% in the group receiving TIVICAY and 86% in the raltegravir group, with a treatment difference of 2.6% and 95% CI of (-1.9%, 7.2%).
c The primary endpoint was assessed at Week 48 and the virologic success rate was 88% in the group receiving TIVICAY and 81% in the ATRIPLA group, with a treatment difference of 7.4% and 95% CI of (2.5%, 12.3%).
d Includes subjects who discontinued due to an adverse event or death at any time point if this resulted in no virologic data on treatment during the analysis window.
e Other includes reasons such as withdrew consent, loss to follow-up, moved, and protocol deviation. |
SPRING-2
Virologic outcomes were also comparable across baseline characteristics including CD4+ cell count, age, and use of EPZICOM or TRUVADA as NRTI background regimen. The median change in CD4+ cell counts from baseline was 276 cells/mm3 in the group receiving TIVICAY and 264 cells/mm3 for the raltegravir group at 96 weeks.
There was no treatment-emergent resistance to dolutegravir or to the NRTI background.
SINGLE
Treatment differences were maintained across baseline characteristics including baseline viral load, CD4+ cell count, age, gender, and race.
The adjusted mean changes in CD4+ cell counts from baseline were 378 cells/mm3 in the group receiving TIVICAY + EPZICOM and 332 cells/mm3 for the ATRIPLA group at 144 weeks. The adjusted difference between treatment arms and 95% CI was 46.9 cells/mm3 (15.6 cells/mm3,78.2 cells/mm3) (adjusted for pre-specified stratification factors: baseline HIV-1 RNA, and baseline CD4+ cell count).
There was no treatment-emergent resistance to dolutegravir, abacavir, or lamivudine.
FLAMINGO
In FLAMINGO, 485 subjects were randomized and received at least 1 dose of either TIVICAY 50 mg once daily (n = 243) or darunavir + ritonavir 800 mg/100 mg once daily (n = 242), both in combination with investigator-selected NRTI background regimen (either fixed-dose abacavir and lamivudine [EPZICOM] or fixed-dose emtricitabine/tenofovir disoproxil fumarate [TRUVADA]). There were 484 subjects included in the efficacy and safety analyses. At baseline, the median age of subjects was 34 years, 15% female, 28% non-white, 10% had hepatitis B and/or C virus co-infection, 3% were CDC Class C (AIDS), 25% had HIV-1 RNA greater than 100,000 copies/mL, and 35% had CD4+ cell count less than 350 cells/mm3; these characteristics were similar between treatment groups. Overall response rates by Snapshot algorithm through Week 96 were 80% for TIVICAY and 68% for darunavir/ritonavir. The proportion of subjects who were non-responders (HIV-1 RNA greater than or equal to 50 copies per mL) at Week 96 was 8% and 12% in the arms receiving TIVICAY and darunavir + ritonavir, respectively; no virologic data were available for 12% and 21% for subjects treated with TIVICAY and darunavir + ritonavir, respectively. The adjusted overall response rate difference in proportion and 95% CI was 12.4% (4.7%, 20.2%). No treatment-emergent primary resistance substitutions were observed in either treatment group.
Treatment-Experienced, Integrase Strand Transfer Inhibitor-Naïve Subjects
In the international, multicenter, double-blind trial (SAILING), 719 HIV-1–infected, antiretroviral treatment-experienced adults were randomized and received either TIVICAY 50 mg once daily or raltegravir 400 mg twice daily with investigator-selected background regimen consisting of up to 2 agents, including at least 1 fully active agent. There were 715 subjects included in the efficacy and safety analyses. At baseline, the median age was 43 years, 32% were female, 50% non-white, 16% had hepatitis B and/or C virus co-infection, 46% were CDC Class C (AIDS), 20% had HIV-1 RNA greater than 100,000 copies/mL, and 72% had CD4+ cell count less than 350 cells/mm3; these characteristics were similar between treatment groups. All subjects had at least 2-class antiretroviral treatment resistance, and 49% of subjects had at least 3-class antiretroviral treatment resistance at baseline. Week 48 outcomes for SAILING are shown in Table 17.
Table 17. Virologic Outcomes of Randomized Treatment in SAILING at 48 Weeks (Snapshot Algorithm)
|
TIVICAY 50 mg Once Daily + BRa
(n = 354) |
Raltegravir 400 mg Twice Daily + BRa
(n = 361) |
| HIV-1 RNA <50 copies/mL |
71% |
64% |
| Adjustedb treatment difference |
7.4% (95% CI: 0.7%, 14.2%) |
| Virologic nonresponse |
20% |
28% |
| No virologic data |
9% |
9% |
Reasons
Discontinued study/study drug due to adverse event or death |
3% |
4% |
| Discontinued study/study drug for other reasonsc |
5% |
4% |
| Missing data during window but on study |
2% |
1% |
| Proportion (%) with HIV-1 RNA <50 copies/mL by Baseline Category |
| Plasma viral load (copies/mL) |
|
|
| ≤50,000 copies/mL |
75% |
71% |
| >50,000 copies/mL |
62% |
47% |
| Background regimen |
|
|
| No darunavir use |
67% |
60% |
| Darunavir use with primary PI substitutions |
85% |
67% |
| Darunavir use without primary PI substitutions |
69% |
70% |
| Gender |
|
|
| Male |
70% |
66% |
| Female |
74% |
60% |
| Race |
|
|
| White |
75% |
71% |
| African-American/African Heritage/Other |
67% |
57% |
a BR = Background regimen. Background regimen was restricted to less than or equal to 2 antiretroviral treatments with at least 1 fully active agent.
b Adjusted for pre-specified stratification factors.
c Other includes reasons such as withdrew consent, loss to follow-up, moved, and protocol deviation. |
Treatment differences were maintained across the baseline characteristics including CD4+ cell count and age.
The mean changes in CD4+ cell counts from baseline were 162 cells/mm3 in the group receiving TIVICAY and 153 cells/mm3 in the raltegravir group.
Treatment-Experienced, Integrase Strand Transfer Inhibitor-Experienced Subjects
VIKING-3 examined the effect of TIVICAY 50 mg twice daily over 7 days of functional monotherapy, followed by OBT with continued treatment of TIVICAY 50 mg twice daily.
In the multicenter, open-label, single-arm VIKING-3 trial, 183 HIV-1–infected, antiretroviral treatment-experienced adults with virological failure and current or historical evidence of raltegravir and/or elvitegravir resistance received TIVICAY 50 mg twice daily with the current failing background regimen for 7 days, then received TIVICAY with OBT from Day 8. A total of 183 subjects enrolled: 133 subjects with INSTI resistance at screening and 50 subjects with only historical evidence of resistance (and not at screening). At baseline, median age of subjects was 48 years; 23% were female, 29% non-white, and 20% had hepatitis B and/or C virus co-infection. Median baseline CD4+ cell count was 140 cells /mm3, median duration of prior antiretroviral treatment was 13 years, and 56% were CDC Class C. Subjects showed multiple-class antiretroviral treatment resistance at baseline: 79% had greater than or equal to 2 NRTI, 75% greater than or equal to 1 NNRTI, and 71% greater than or equal to 2 PI major substitutions; 62% had non-R5 virus.
Mean reduction from baseline in HIV-1 RNA at Day 8 (primary endpoint) was 1.4log10 (95% CI:1.3 log10, 1.5 log10). Response at Week 48 was affected by baseline INSTI substitutions [see Microbiology].
After the functional monotherapy phase, subjects had the opportunity to re-optimize their background regimen when possible. Week 48 virologic outcomes for VIKING-3 are shown in Table 18.
Table 18. Virologic Outcomes of Treatment of VIKING-3 at 48 Weeks (Snapshot Algorithm)
|
TIVICAY 50 mg Twice Daily + OBT
(n = 183) |
| HIV-1 RNA <50 copies/mL |
63% |
| Virologic nonresponse |
32% |
| No virologic data |
|
Reasons
Discontinued study/study drug due to adverse event or death |
3% |
| Proportion (%) with HIV-1 RNA <50 copies/mL by Baseline Category |
| Gender |
|
| Male |
63% |
| Female |
64% |
| Race |
|
| White |
63% |
| African-American/African Heritage/Other |
64% |
| OBT = Optimized Background Therapy. |
Subjects harboring virus with Q148 and with additional Q148-associated secondary substitutions also had a reduced response at Week 48 in a stepwise fashion [see Microbiology].
The median change in CD4+ cell count from baseline was 80 cells/mm3 at Week 48.
Virologically Suppressed Subjects
SWORD-1 and SWORD-2 are identical 148-week, Phase 3, randomized, multicenter, parallel-group, non-inferiority trials. A total of 1,024 adult HIV-1–infected subjects who were on a stable suppressive antiretroviral regimen (containing 2 NRTIs plus either an INSTI, an NNRTI, or a PI) for at least 6 months (HIV-1 RNA less than 50 copies/mL), with no history of treatment failure and no known substitutions associated with resistance to dolutegravir or rilpivirine received treatment in the trials. Subjects were randomized 1:1 to continue their current antiretroviral regimen (n°= 511) or be switched to TIVICAY 50 mg plus rilpivirine 25 mg administered once daily (n° = 513). Subjects originally assigned to continue their current antiretroviral regimen and who remained virologically suppressed at Week 48 switched to TIVICAY plus rilpivirine at Week 52 (n = 477).
The primary efficacy endpoint for the SWORD trial was the proportion of subjects with plasma HIV-1 RNA less than 50 copies/mL at Week 48. The proportion of subjects with HIV-1 RNA less than 50 copies/mL at Week 48 was 95% for both treatment groups; treatment difference and 95% CI was -0.2% (-3.0%, 2.5%). The proportion of subjects with HIV-1 RNA greater than or equal to 50 copies /mL (virologic failure) at Week 48 was 0.6% and 1.2% for the dolutegravir plus rilpivirine treatment group and the current antiretroviral regimen treatment groups, respectively; treatment difference and 95% CI was -0.6% (-1.7%, 0.6%). At Week 148 in the pooled SWORD-1 and SWORD-2 trials, 84% of subjects who received TIVICAY plus rilpivirine from study start had plasma HIV-1 RNA less than 50 copies/mL (Snapshot algorithm). In subjects who initially remained on their current antiretroviral regimen and switched to TIVICAY plus rilpivirine at Week 52, 90% had plasma HIV-1 RNA less than 50 copies/mL at Week 148 (Snapshot algorithm), which was comparable to the response rate (89%) observed at Week 100 (similar exposure duration) in subjects receiving TIVICAY plus rilpivirine from study start.
Refer to the prescribing information for JULUCA (dolutegravir and rilpivirine) tablet for complete virologic outcome information.
Pediatric Subjects
IMPAACT P1093 is an ongoing Phase 1/2, multicenter, open-label trial to evaluate the pharmacokinetic parameters, safety, tolerability, and efficacy of TIVICAY or TIVICAY PD in combination treatment regimens in HIV-1–infected infants, children, and adolescents aged at least 4 weeks to 18 years. Subjects were stratified by 5 age cohorts: Cohort 1, aged 12 to less than 18 years; Cohort 2A, aged 6 to less than 12 years; Cohort 3, aged 2 to less than 6 years; Cohort 4, aged 6 months to less than 2 years; and Cohort 5, aged 4 weeks to less than 6 months. Seventy-five subjects received the recommended dose (determined by weight and age) of TIVICAY or TIVICAY PD [see DOSAGE AND ADMINISTRATION].
These 75 subjects had a median age of 27 months (range: 1 to 214), were 59% female, and 68% were Black or African American. At baseline, mean plasma HIV-1 RNA was 4.4 log10 copies/mL, median CD4+ cell count was 1,225 cells/mm3 (range: 1 to 8,255), and median CD4+% was 23% (range: 0.3% to 49%). Overall, 33% had baseline plasma HIV-1 RNA greater than 50,000 copies/mL and 12% had a CDC HIV clinical classification of category C. The majority (80%) of subjects were treatment-experienced, but all were INSTI-naïve. Most subjects had previously used at least 1 NNRTI (44%) or 1 PI (76%).
Virologic outcomes from IMPAACT P1093 include subjects who received either TIVICAY tablets or TIVICAY PD tablets for oral suspension as per the dosing recommendations for their weight band and who had reached Week 24 (n = 58) or Week 48 (n = 42). At Week 24, 62% of subjects achieved HIV-1 RNA less than 50 copies/mL and 86% achieved HIV-1 RNA less than 400 copies/mL (Snapshot algorithm). The median CD4 count (percent) increase from baseline to Week 24 was 105 cells/mm3 (5%). At Week 48, 69% of subjects achieved HIV-1 RNA less than 50 copies/mL and 79% achieved HIV-1 RNA less than 400 copies/mL (Snapshot algorithm). The median CD4 count (percent) increase from baseline to Week 48 was 141 cells/mm3 (7%).