In this phase IIIb, open label, non-inferiority study, virologically suppressed* adults with HIV-1 receiving daily oral therapy with BIC/FTC/TAF were randomised to one of three arms for the duration of the 12-month maintenance period*:

Due to protocol non-compliance, 11 subjects from one site were excluded from the intention-to-treat exposed (ITT-E) population, creating a modified intention-to-treat exposed (mITT-E) population. Efficacy is reported on a mITT-E analysis.[1]

SOLAR explored virological suppression, safety and tolerability, as well as patient treatment experiences with every-2-month VOCABRIA + REKAMBYS vs daily oral therapy with BIC/⁠FTC/⁠TAF[1]

Outcomes were measured at Month 12 for participants in the oral lead-in (OLI) and BIC/⁠FTC/⁠TAF groups and Month 11 for participants in the start with injection (SWI) group[1,2]

Efficacy and safety endpoints at Month 12 included:[1,2]

  • Proportion of patients with plasma HIV-1 RNA ≥50 copies/mL (primary endpoint)
  • Proportion with plasma HIV-1 RNA <50 copies/mL
  • Incidence of confirmed virologic failure (CVF)
  • Adverse events (AEs)

Patient treatment experience outcomes included:[1,2]

  • Patient preference
  • Reasons for preference
  • Treatment satisfaction

The SOLAR study endpoint was met (mITT- E population): Every-2-month VOCABRIA +REKAMBYS was non-inferior to daily oral therapy with BIC/FTC/TAF at month 12 (1.1% with plasma HIV-1 RNA ≥50 copies /ml [n=5/447] vs 0.4 [n=1/223], respectively)[3]

Key inclusion and exclusion criteria:[2]


  • No history of non-nucleoside reverse transcriptase inhibitors (NNRTIs), protease inhibitors (PIs), C-C Chemokine receptor 5 or other entry inhibitors
  • Must be on the uninterrupted current regimen of BIC/FTC/TAF for ≥6 months prior to screening with an undetectable HIV-1 viral load for ≥6 months prior to screening. BIC/FTC/TAF must be the patient’s first or second regimen. If it is their second regimen, their previous regimen must have been integrase inhibitor (INI)-based


  • History of virologic failure
  • Known or suspected presence of resistance mutations to the individual components of BIC/⁠FTC/⁠TAF, cabotegravir and rilpivirine
  • Hepatitis B virus (HBV) infection at screening
  • Moderate to severe hepatic impairment
  • Women who were pregnant or breastfeeding or planned to become pregnant or breastfeed


SOLAR included a range of participants[1]

Among the 447 participants switching to every-2-month VOCABRIA + REKAMBYS (mITT‑E):[1]

Among study participants, 12 transgender females, 1 transgender male, and 1 gender non-conforming individual were included[1]

Challenges revealed by SOLAR patients on daily oral therapy with BIC/FTC/TAF at baseline[1]

Worried about people unintentionally discovering their HIV status

Worried about forgetting to take their HIV medication

Felt that taking their HIV medication was an uncomfortable reminder of their HIV status

*Participants were suppressed for ≥6 months, virologic suppression defined as HIV-1 RNA <50 copies/⁠mL and received BIC/FTC/TAF for ≥6 months prior to screening.[1]
Cabotegravir injections, 600 mg; rilpivirine injections, 900 mg.[1]
CVF defined as 2 consecutive measurements of HIV-1 RNA ≥200 copies/mL.[1]

AE=adverse event; BIC/FTC/TAF=bictegravir/emtricitabine/tenofovir alafenamide; BMI=body mass index; CAB=cabotegravir; CVF=confirmed virologic failure; HBV=hepatitis B virus; HIV=human immunodeficiency virus; HIV-1=human immunodeficiency virus type 1; INI=integrase inhibitor; LA=long-acting; mITT-E=modified intention-to-treat exposed; NNRTI=non-nucleoside reverse transcriptase inhibitor; OLI=oral lead-in; PI=protease inhibitor; PLHIV=people living with HIV-1; RNA=ribonucleic acid; RPV=rilpivirine; SWI=start with injection.


  1. Ramgopal MN, Castagna A, Cazanave C, et al. SOLAR 12-Month Results – Randomized Switch Trial of CAB + RPV LA vs. Oral BIC/FTC/TAF. Presented at Conference on Retroviruses and Opportunistic Infections (CROI): February 19–22, 2023. REF-182990.
  2. A Study to Evaluate Efficacy and Safety of Cabotegravir (CAB) Long Acting (LA) Plus (+) Rilpivirine (RPV) LA Versus BIKTARVY (BIK) in Participants With Human Immunodeficiency Virus (HIV)-1 Who Are Virologically Suppressed (SOLAR). 2022. REF-182394. Accessed January 30, 2023.

REKAMBYS (rilpivirine long-acting injection), including the trademark, is owned by the Janssen Pharmaceutical Companies and used under licence by the ViiV Healthcare group of companies. All other trademarks are owned by the ViiV Healthcare group.

PM-GB-CBR-WCNT-230001 | March 2024

Adverse event reporting

Adverse events should be reported. Reporting forms and information can be found at or search for MHRA Yellowcard in the Google Play or Apple App store. Adverse events should also be reported to GlaxoSmithKline on 0800 221441.

If you are from outside the UK, you can report adverse events to GSK/ViiV by selecting your region and market, here.