Clinical trial design and efficacy results for RUKOBIA (fostemsavir)

BRIGHTE: a ~5-year, Phase 3 trial with 371 participants living with MDR HIV-11

BRIGHTE is an ongoing Phase 3, international, double-blind, placebo-controlled trial evaluating the efficacy and safety of RUKOBIA in people living with multidrug-resistant HIV-1.1 The significant antiviral activity of RUKOBIA at Day 8, as well as long-term data through Week 240, is presented below.

Additional endpoints in BRIGHTE for RUKOBIA include virologic suppression and change in CD4+ T-cell counts.

All participants in BRIGHTE were living with MDR HIV-1 and failing their current ARV regimens with a viral load of ≥400 copies/mL at enrollment.1

BRIGHTE is an ongoing Phase 3, international, double-blind, placebo-controlled trial evaluating the efficacy and safety of RUKOBIA in people living with multidrug-resistant HIV-1.1 The significant antiviral activity of RUKOBIA at Day 8, as well as long-term data through Week 240, is presented below. Additional endpoints in BRIGHTE for RUKOBIA include virologic suppression and change in CD4+ T-cell counts.

All participants in BRIGHTE were living with MDR HIV-1 and failing their current ARV regimens with a viral load of ≥400 copies/mL at enrollment.1

BRIGHTE trial design2

Schematic of the BRIGHTE phase 3, international, double-blind, placebo-controlled efficacy and safety trial

Primary endpoint2

  • Adjusted mean plasma HIV-1 RNA log10 change from Days 1 to 8 (randomized cohort)

*Two participants in the RUKOBIA + failing regimen arm who had missing Day 1 HIV-1 RNA values were not included in the analysis at Day 8.

Investigator-selected OBT (based on resistance testing and treatment history).2

In BRIGHTE, RUKOBIA was used in combination with other ARVs to optimize the ARV regimen4,5

  • DTG, DRV, and TFV were the most common ARVs included in the optimized background therapy

Common ARVs in the initial OBT for each cohort in BRIGHTE

Bar graphs showing commonly used antiretroviral drugs among BRIGHTE trial participants

3TC or FTC were included in 50% and 77% of OBT in the randomized cohort and nonrandomized cohort, respectively.

 

ARVs in the figure above include those that were in the initial OBT for at least 10% of study participants.
 

For the nonrandomized cohort, experimental ARVs other than RUKOBIA were assumed to be fully active.5

§Based on the screening criteria for activity (according to screening and historical resistance measures).5

Of these 19 participants, 15 received ibalizumab, which was an investigational agent at the start of BRIGHTE. Four patients had 1 fully active ARV class remaining and were classified as protocol deviations.5

BRIGHTE included a broad range of people living with MDR HIV-12,5,6

1 to 2 active ARV classes

Baseline characteristics for randomized cohort (n=272)

Graphic showing median age of 48, median viral load of 4.7 log10 copies/mL, median CD4+ T-cell count of 99.5 cells/mm3, and % of participants across sex and ethnicities

Baseline CD4+ counts for randomized cohort (n=272)

Graphic showing % of participants with baseline CD4+ counts of ≥200 cells/mm3, 20-199 cells/mm3, and 1-19 cells/mm3

Additional baseline characteristics for randomized cohort

Graphic showing 85% of participants had a history of AIDS and 52% had only 1 fully active and available ARV

Patients in the Hispanic ethnic group could also be included in a racial group.2

No fully active ARV agents

Baseline characteristics for nonrandomized cohort (n=99)

Graphic showing median age of 50, median viral load of 4.3 log10 copies/mL, median CD4+ T-cell count of 41 cells/mm3, and % of participants across sex and ethnicities

Baseline CD4+ counts for nonrandomized cohort (n=99)

Graphic showing % of participants with baseline CD4+ counts of ≥200 cells/mm3, 20-199 cells/mm3, and 1-19 cells/mm3

Additional baseline characteristics for nonrandomized cohort

Graphic showing 90% of participants had a history of AIDS and 19% had only 1 fully active and available ARV

Patients in the Hispanic ethnic group could also be included in a racial group.2

#Of the 19 participants, 15 received ibalizumab, which was an investigational agent at the start of BRIGHTE. Four patients had 1 fully active ARV class remaining and were classified as protocol deviations.3

Superior antiviral activity at Day 8

Primary endpoint (randomized cohort): Decline in mean plasma viral load

Bar graph comparing efficacy of RUKOBIA + failing regimen to placebo + failing regimen

*Two participants who received RUKOBIA with missing Day 1 HIV-1 RNA values were not included in this analysis.

Rates of virologic suppression1,5,7

Virological response (HIV-1 RNA <40 copies/mL) for RUKOBIA + OBT through ~5 years (randomized cohort)

Results are descriptive.

Line graph showing long-term responses to RUKOBIA across varying analysis parameters in the randomized cohort
  • At Week 240, 19 participants were unable to have their HIV-1 RNA values assessed due to the impact of COVID-19 and therefore counted as failures in the Snapshot Analysis1

Included in the Snapshot Analysis5

  • The ITT–E population included all randomized participants who received at least 1 dose of treatment
  • The FDA Snapshot Algorithm was used to evaluate rates of virologic suppression among all ITT–E patients
  • In the ITT–E population, missing data or change in OBT was counted as virologic failure

Included in the Observed Analysis5

  • The Observed Analysis included only participants for whom HIV-1 RNA values were measured at each study visit, potentially favoring treatment successes

At Week 240, 12 participants (7 in the randomized cohort and 5 in the nonrandomized cohort) had completed the study by transitioning to locally approved fostemsavir (the first fostemsavir approval was in the US in July 2020).1

Virological response (HIV-1 RNA <40 copies/mL) for RUKOBIA + OBT in the nonrandomized cohort (exploratory endpoint)

Results are descriptive.

Line graph showing long-term responses to RUKOBIA across varying analysis parameters in the nonrandomized cohort
  • At Week 240, 5 participants were unable to have their HIV-1 RNA values assessed due to the impact of COVID-19 and therefore counted as failures in the Snapshot Analysis1

Included in the Snapshot Analysis5

  • The ITT–E population included all randomized participants who received at least 1 dose of treatment
  • The FDA Snapshot Algorithm was used to evaluate rates of virologic suppression among all lTT–E patients
  • In the ITT–E population, missing data or change in OBT was counted as virologic failure

Included in the Observed Analysis5

  • The Observed Analysis included only participants for whom HIV-1 RNA values were measured at each study visit, potentially favoring treatment successes

For the nonrandomized exploratory treatment arm (n=99), 15 participants received ibalizumab, an investigational agent, at the start of BRIGHTE, and 4 patients were incorrectly assigned to the nonrandomized cohort.2

§At Week 240, 12 participants (7 in the randomized cohort and 5 in the nonrandomized cohort) had completed the study by transitioning to locally approved fostemsavir (the first fostemsavir approval was in the US in July 2020).1

Virologic suppression across subgroups1,7

Virologic response with RUKOBIA + OBT at ~5 years by subgroups5

Results are descriptive.

Subgroup % of Participants
Virologically Suppressed
(HIV-1 RNA <40 copies/mL) at Week 240
Age, years
<35 39% (24/61)
35 to <50 48% (48/100)
≥50 45% (48/106)
Gender
Male 45% (90/198)
Female 43% (30/69)
Race
White 43% (78/183)
Black or African
American
48% (28/58)
American Indian
or Alaska Native
43% (3/7)
Native Hawaiian or
Other Pacific Islander
0% (0/1)
Asian 50% (1/2)
Other Races 63% (10/16)

Virologic outcomes (HIV-1 RNA <40 copies/mL) by subgroup (randomized cohort, ITT–E population, Snapshot algorithm) at Week 96:

  • Male, 59% (118/200); female, 63% (45/72)
  • White, 56% (103/185); Black or African American/Other Races, 69% (60/87)
  • Age <50, 59% (96/162); age ≥50, 61% (67/110)

Virologic failure over time by Snapshot Analysis (ITT–E)1

Protocol-defined VF with RUKOBIA + OBT

Randomized Cohort RUKOBIA
600 mg BID
Week 96 (N=272), n (%) Week 240 (N=267), n (%)
63 (23)* 80 (29)

PDVF was defined as the following: before Week 24, confirmed HIV-1 RNA ≥400 copies/mL after confirmed suppression to <400 copies/mL, or confirmed >1 log10 copies/mL increase in HIV-1 RNA above nadir where nadir is ≥40 copies/mL; at or after Week 24, confirmed HIV-1 RNA ≥400 copies/mL.1

  • Through Week 96 in the randomized cohort, 55% (29/53) of participants with virologic failure who had post-baseline data had treatment-emergent gp120 resistance-associated substitutions at 4 key sites (S375H/I/M/N/T, M426L/I, M434I/L, M475I/L/V)

*Through Week 96, the PI for RUKOBIA identifies 69 of 272 (25%) participants in the randomized cohort and 50 of 99 (51%) of participants in the nonrandomized cohort as experiencing VF. The definition for VF used in the PI differs from the definition of PDVF. Per the PI, VF=confirmed ≥400 copies/mL after prior confirmed suppression to <400 copies/mL, ≥400 copies/mL at last available value prior to discontinuation, or >1 log10 copies/mL increase in HIV-1 RNA at any time above the nadir level (≥40 copies/mL).

No fully active ARV agents

Virologic response with RUKOBIA + OBT at ~5 years by subgroups (exploratory analysis)7

Results are descriptive.

Subgroup % of Participants
Virologically Suppressed
(HIV-1 RNA <40 copies/mL) at Week 240
Age, years
<35 8% (1/12)
35 to <50 39% (11/28)
≥50 15% (8/52)
Gender
Male 23% (19/83)
Female 11% (1/9)
Race
White 26% (18/70)
Black or African
American
10% (2/20)
American Indian
or Alaska Native
0% (0/1)
Native Hawaiian or
Other Pacific Islander
N/A
Asian N/A
Other Races 0% (0/1)

Virologic failure over time by Snapshot Analysis (ITT–E)1

Protocol-defined VF with RUKOBIA + OBT

Nonrandomized Cohort RUKOBIA
600 mg BID
Week 96 (N=99), n (%) Week 240 (N=92), n (%)
49 (49) 53 (54)

PDVF was defined as the following: before Week 24, confirmed HIV-1 RNA ≥400 copies/mL after confirmed suppression to <400 copies/mL, or confirmed >1 log10 copies/mL increase in HIV-1 RNA above nadir where nadir is ≥40 copies/mL; at or after Week 24, confirmed HIV-1 RNA ≥400 copies/mL.1

For the nonrandomized exploratory treatment arm (n=99), 15 participants received ibalizumab, an investigational agent, at the start of BRIGHTE, and 4 patients were incorrectly assigned to the nonrandomized cohort.2

Through Week 96, the PI for RUKOBIA identifies 69 of 272 (25%) participants in the randomized cohort and 50 of 99 (51%) of participants in the nonrandomized cohort as experiencing VF. The definition for VF used in the PI differs from the definition of PDVF. Per the PI, VF=confirmed ≥400 copies/mL after prior confirmed suppression to <400 copies/mL, ≥400 copies/mL at last available value prior to discontinuation, or >1 log10 copies/mL increase in HIV-1 RNA at any time above the nadir level (≥40 copies/mL).

Robust CD4+ T-cell recovery across all subgroups1,3

Increase in CD4​+ T-cells with RUKOBIA + OBT through ~5 years (randomized cohort, observed analysis)

Line graph showing change in number of CD4+ T-cells for BRIGHTE participants with varied initial cell counts

Results are descriptive.

  • The observed analysis included only participants for whom CD4+ lab values were measured at each study visit, potentially favoring treatment successes2
  • All participant subgroups categorized by baseline CD4+ T-cell count experienced a mean CD4+ T-cell increase by Week 240, based on a subgroup analysis​1

*At Week 240, 19 participants did not have their data included in this analysis due to the impact of COVID-19.1

CD4+ T-cell counts ≥200 cells/mm3 in the majority of participants through ~5 years (observed analysis)1,7

CD4+ T-cell counts ≥200 cells/mmwith RUKOBIA + OBT (randomized cohort, observed analysis)

Bar graph showing % of participants with CD4+ T-cell counts above the CD4+ T-cell counts ≥ 200 cells/mm3 at baseline and Weeks 96 & 240
  • The observed analysis included only individuals for whom CD4+ lab values were measured at each study visit, potentially favoring treatment successes2

Robust CD4+ T-cell recovery despite no fully active and approved ARV agents in OBT1

Increase in CD4+ T-cells from baseline with RUKOBIA + OBT through 
~5 years (nonrandomized cohort, exploratory analysis; results are descriptive)1†

Line graph showing long-term mean change in CD4+ T-cell counts for BRIGHTE participants

For the nonrandomized exploratory treatment arm (n=99), 15 participants received ibalizumab, an investigational agent, at the start of BRIGHTE, and 4 patients were incorrectly assigned to the nonrandomized cohort.2

At Week 240, 5 participants did not have their data included in this analysis due to the impact of COVID-19.1

Transcript

Dr. Tony Mills reviews exciting long-term data for RUKOBIA

BRIGHTE Long-Term Data

The BRIGHTE study provides ~5-year efficacy results1

3TC=lamivudine; AIDS=acquired immunodeficiency syndrome; ARV=antiretroviral; BID=twice daily; CI=confidence interval; DRV=darunavir; DTG=dolutegravir; ENF=enfuvirtide; ETR=etravirine; FTC=emtricitabine; gp120=glycoprotein 120; HIV-1=human immunodeficiency virus type-1; IBA=ibalizumab; ITT–E=intent-to-treat–exposed; MDR=multidrug-resistant; MVC=maraviroc; OBT=optimized background therapy; PDVF=protocol-defined virologic failure; PI=prescribing information; RNA=ribonucleic acid; TDF=tenofovir disoproxil fumarate; TFV=tenofovir; VF=virologic failure.

References:

  1. Aberg JA, Shepherd B, Wang M, et al. Week 240 efficacy and safety of fostemsavir plus optimized background therapy in heavily treatment-experienced adults with HIV-1. Infect Dis Ther. 2023;12(9):2321-2335. doi:10.1007/s40121-023-00870-6
  2. Kozal M, Aberg J, Pialoux G, et al. Fostemsavir in adults with multidrug-resistant HIV-1 infection. N Engl J Med. 2020;382(13):1232-1243.
  3. Aberg J, Shepherd B, Wang M, et al. Efficacy and safety of fostemsavir plus optimized background therapy in heavily treatment-experienced adults with HIV-1: week 240 results of the phase 3 BRIGHTE study. Poster presented at: 24th International AIDS Conference; July 29–August 2, 2022; Montreal, Canada. Poster EPB160.
  4. Ackerman P, Wilkin T, Pierce A, et al. Clinical impact of antiretroviral agents used in optimized background therapy with fostemsavir in heavily treatment-experienced adults with HIV-1: exploratory analyses of the phase 3 BRIGHTE study. Presented at: 11th IAS Conference on HIV Science; July 18-21, 2021; Virtual. Poster PEB155.
  5. Lataillade M, Lalezari JP, Kozal M, et al. Safety and efficacy of the HIV-1 attachment inhibitor prodrug fostemsavir in heavily treatment-experienced individuals: week 96 results of the phase 3 BRIGHTE study. Lancet HIV. 2020;7(11):e740-e751. doi:10.1016/S2352-3018(20)30240-X
  6. Ackerman P, Thompson M, Molina JM, et al. Long-term efficacy and safety of fostemsavir among subgroups of heavily treatment-experienced adults with HIV-1. AIDS. 2021;35(7):1061-1072.
  7. Data on file, ViiV Healthcare.

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