ViiV HEALTHCARE PRESENTS POSITIVE FIVE-YEAR DATA AT AIDS 2022, DEMONSTRATING THE DURABILITY OF FOSTEMSAVIR IN PEOPLE LIVING WITH HIV WHO ARE HEAVILY TREATMENT-EXPERIENCED

Kimberly Smith, M.D., Head of Research & Development at ViiV Healthcare, said: “These results are so significant because fostemsavir is the only treatment available for this specific population, with such long-term, thorough data. With such a clinically meaningful improvement in CD4+ count in the study population, these extensive and robust study findings demonstrate the durability of fostemsavir and its suitability as a treatment for these people living with HIV. Given these findings fostemsavir remains a good representation of our commitment to developing innovative medicines for all people living with HIV, regardless of where they are in their treatment journey.”

In the randomised cohort, rates of virologic response generally remained consistent over time through week 240, with 45% (120/272) of patients receiving fostemsavir plus OBT in the randomised cohort achieving virologic suppression (HIV-1 RNA <40 copies per millilitre [c/mL]).¹ Reduced virologic response rates by Snapshot analysis beyond week 192 were partially confounded by missing data because of COVID-19 pandemic as well as changes in OBT and others.¹ CD4+ cell counts increased steadily from baseline (n = 272) over time and increased by 296 cells/mm³ by week 240. In the randomised cohort, 78% (73/94) of participants had a change in CD4+ cell count from <200 cells/mm³ to ≥200 cells/mm³, and 67% (22/33) had a change from <20 cells/mm³ to ≥200 cells/mm³.¹ CD4+/CD8+ ratio also increased steadily from baseline, reaching a mean of 0.6 in the randomised cohort by week 240.¹

At week 240, the safety profile was consistent with earlier findings across both cohorts, and no new trends in the safety data were identified.¹ In the randomised cohort, 95% (259/272) of patients experienced at least one adverse event (AE), with the most common drug-related AEs across both groups being nausea (35/371, 9%) and diarrhoea (18/371, 5%). At least one serious adverse event (SAE) was experienced by 45% (122/272) of patients in the randomised cohort, the most common of which were due to infections and not related to the study medication (fostemsavir + OBT). In total, 4% (10/272) of SAEs in the randomised cohort were related to the study medication, with 4 participants discontinuing because of an AE between week 96 and week 240. Of 35 deaths, 12 were AIDS-related (5 new since week 96), 12 were acute infections (1 new since week 96), 6 were non-AIDS-related malignancies, and the remaining 5 were related to other conditions. During the study, 25/371 participants were diagnosed with 28 COVID-19 and COVID-19 related events. All cases resolved without reported sequelae, and there were no COVID-19 related deaths or reports of post-COVID-19 syndrome.

About BRIGHTE (NCT02362503)

The BRIGHTE trial is an international, phase III, partially-randomised, double-blind, placebo-controlled study conducted in 371 heavily treatment-experienced (HTE) adults living with HIV-1 infection with multidrug resistance. All trial participants were required to have a viral load ≥400 copies/mL and ≤2 classes of ARV medications remaining at baseline due to resistance, intolerability, contraindication, or other safety considerations. Trial participants were enrolled in either a randomised or non-randomised cohort defined as follows:

• Within the randomised cohort (n = 272), participants had 1, but no more than 2, fully active and available ARV agent(s) at screening, which could be combined as part of an efficacious background regimen. Randomised participants received either blinded fostemsavir 600mg twice daily (n = 203) or placebo (n = 69) in addition to their current failing regimen for 8 days of functional monotherapy. Beyond Day 8, randomised participants received open-label fostemsavir 600mg twice daily plus an investigator-selected optimised background therapy (OBT). The randomised cohort provides primary evidence of efficacy of fostemsavir.
• Within the non-randomised cohort (n = 99), participants had no fully active and licensed ARV agent(s) available at screening. Non-randomised participants were treated with open label fostemsavir 600mg twice daily plus OBT from Day 1 onward. The use of an investigational drug(s) as a component of the optimised background therapy was permitted in the non-randomised cohort.

The primary endpoint analysis, based on the adjusted mean decline in HIV-1 RNA from Day 1 at Day 8 in the randomised cohort, demonstrated superiority of fostemsavir to placebo (0.79 vs 0.17 log₁₀ copies/mL decline, respectively; P<0.0001, Intent-to-Treat-Exposed [ITT-E] population).

Important Safety Information (ISI)

The following ISI is based on the Highlights section of the U.S. Prescribing Information for RUKOBIA. Please consult the full U.S. Prescribing Information for all the labelled safety information for RUKOBIA.

INDICATIONS AND USAGE

• RUKOBIA, a human immunodeficiency virus type 1 (HIV-1) gp120-directed attachment inhibitor, in combination with other antiretroviral(s), is indicated for the treatment of HIV-1 infection in heavily treatment-experienced adults with multidrug-resistant HIV-1 infection failing their current antiretroviral regimen due to resistance, intolerance, or safety considerations.

DOSAGE AND ADMINISTRATION

• One tablet taken twice daily with or without food.

DOSAGE FORMS AND STRENGTHS

• Extended release tablets: 600 mg

CONTRAINDICATIONS

• Hypersensitivity to fostemsavir or any of the components of the formulation.
• Coadministration with strong cytochrome P450 (CYP)3A inducers as significant decreases in temsavir plasma concentrations may occur, which may result in loss of virologic response.

ADVERSE REACTIONS

• The most common adverse reactions (all grades) observed in ≥5% of randomized and non-randomized participants were nausea, fatigue and diarrhoea.

DRUG INTERACTIONS

• See full U.S. prescribing information for complete list of significant drug interactions.
• Doses of oral contraceptives should not contain more than 30 mcg of ethinyl estradiol per day.

USE IN SPECIFIC POPULATIONS

• Lactation: Breastfeeding is not recommended due to the potential for HIV-1 transmission.

About GSK

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