Adverse drug reactions in South African patients receiving bedaquiline-containing tuberculosis treatment: an evaluation of spontaneously reported cases.

BACKGROUND: Bedaquiline was recently introduced into World Health Organization (WHO)-recommended regimens for treatment of drug resistant tuberculosis. There is limited data on the long-term safety of bedaquiline. Because bedaquiline prolongs the QT interval, there are concerns regarding cardiovascular safety. The Western Cape Province in South Africa has an established pharmacovigilance programme: a targeted spontaneous reporting system which solicits reports of suspected adverse drug reactions (ADRs) in patients with HIV-1 and/or tuberculosis infection. Since 2015, bedaquiline has been included in the treatment regimens recommended for resistant tuberculosis in South Africa. We describe ADRs in patients on bedaquiline-containing tuberculosis treatment that were reported to the Western Cape Pharmacovigilance programme. METHODS: We reviewed reports of suspected ADRs and deaths received between March 2015 and June 2016 involving patients receiving bedaquiline-containing tuberculosis treatment. A multidisciplinary panel assessed causality, and categorised suspected ADRs using World Health Organisation-Uppsala Monitoring Centre system categories. "Confirmed ADRs" included all ADRs categorised as definite, probable or possible. Preventability was assessed using Schumock and Thornton criteria. Where a confirmed ADR occurred in a patient who died, the panel categorised the extent to which the ADR contributed to the patient's death as follows: major contributor, contributor or non-contributor. RESULTS: Thirty-five suspected ADRs were reported in 32 patients, including 13 deaths. There were 30 confirmed ADRs, of which 23 were classified as "possible" and seven as "probable". Bedaquiline was implicated in 22 confirmed ADRs in 22 patients. The most common confirmed ADR in patients receiving bedaquiline was QT prolongation (8 cases, 7 of which were severe). A fatal arrhythmia was suspected in 4 sudden deaths. These 4 patients were all taking bedaquiline together with other QT-prolonging drugs. There were 8 non-bedaquiline-associated ADRs, of which 7 contributed to deaths. CONCLUSIONS: Confirmed ADRs in patients receiving bedaquiline reflect the known safety profile of bedaquiline. Quantifying the incidence and clinical consequences of severe QT-prolongation in patients receiving bedaquiline-containing regimens is a research priority to inform recommendations for patient monitoring in treatment programmes for drug resistant tuberculosis. Pharmacovigilance systems within tuberculosis treatment programmes should be supported and encouraged, to provide ongoing monitoring of treatment-limiting drug toxicity.

A cluster randomized controlled trial of extending ART refill intervals to six-monthly for anti-retroviral adherence clubs.

BACKGROUND: The antiretroviral therapy (ART) adherence club (AC) differentiated service delivery model, where clinically stable ART patients receive their ART refills and psychosocial support in groups has supported clinically stable patients' retention and viral suppression. Patients and health systems could benefit further by reducing visit frequency and increasing ART refills. We designed a cluster-randomized control trial comparing standard of care (SoC) ACs and six-month ART refill (Intervention) ACs in a large primary care facility in Khayelitsha, South Africa. METHODS: Existing ACs were randomized to either the control (SOC ACs) or intervention (Intervention ACs) arm. SoC ACs meet five times annually, receiving two-month ART refills with a four-month ART refill over year-end. Blood is drawn at the AC visit ahead of the clinical assessment visit. Intervention ACs meet twice annually receiving six-month ART refills, with a third individual visit for routine blood collection anytime two-four weeks before the annual clinical assessment AC visit. Primary outcomes will be retention in care, annual viral load assessment completion and viral load suppression. (<400copies/mL) after 2 years. Ethics approval has been granted by the University of Cape Town (HREC 652/2016) and the Medecins Sans Frontieres (MSF) Ethics Review Board (#1639). Results will be published in peer-reviewed journals and made widely available through presentations and briefing documents. DISCUSSION: Evaluation of an extended ART refill interval in adherence clubs will provide evidence towards novel model adaptions that can be made to further improve convenience for patients and leverage health system efficiencies. TRIAL REGISTRATION: Registered with the Pan African Clinical Trial Registry: PACTR201810631281009. Registered 11 September 2018.

Virologic outcomes with tenofovir-lamivudine-dolutegravir in adults failing PI-based second-line ART.

Background: In South African antiretroviral guidelines, selected patients failing second-line protease inhibitor (PI)-based therapy qualify for genotypic resistance testing - those with PI resistance receive darunavir-based third-line regimens; those without PI resistance continue current regimen with adherence support. The Western Cape province, from September 2020, implemented a strategy of tenofovir-lamivudine-dolutegravir (TLD) for patients, provided there was no tenofovir resistance, irrespective of PI resistance. Objectives: To evaluate virologic outcomes with TLD among adults failing second-line PI regimens with no tenofovir resistance. Method: An observational cohort study comparing outcomes in patients switched to TLD with those continuing the same PI or switched to darunavir-based regimens. Follow-up was until virologic suppression (HIV-1 RNA < 400 copies/mL), or at the point of censoring. Results: One hundred and thirty-three patients switched to TLD, 101 to darunavir-based regimens, and 121 continued with the same PI. By 12 months, among patients with PI resistance, 42/47 (89%) in the TLD group had HIV-1 RNA < 400 copies/mL compared to 91/99 (92%) in the darunavir group (hazard ratio, 1.11; 95% confidence interval, 0.77-1.60). In patients without PI resistance, 66/86 (77%) in the TLD group had HIV-1 RNA < 400 copies/mL compared to 42/120 (35%) in those continuing with the same PI (hazard ratio, 4.03; 95% confidence interval, 2.71-5.98). Two patients receiving TLD developed virologic failure with high-level dolutegravir resistance. Conclusion: Amongst patients failing second-line PI with no PI resistance, switching to TLD was associated with higher virologic suppression, likely due to improved adherence. Virologic outcomes were similar in patients with PI resistance switched to darunavir-based regimens or TLD.

Twenty-four-month outcomes from a cluster-randomized controlled trial of extending antiretroviral therapy refills in ART adherence clubs.

INTRODUCTION: The antiretroviral therapy (ART) adherence club (AC) model has supported clinically stable HIV patients' retention with group ART refills and psychosocial support. Reducing visit frequency by increasing ART refills to six months could further benefit patients and unburden health systems. We conducted a pragmatic non-inferiority cluster randomized trial comparing standard of care (SoC) ACs and six-month refill intervention ACs in a primary care facility in Khayelitsha, South Africa. METHODS: Existing community-based and facility-based ACs were randomized to either SoC or intervention ACs. SoC ACs met five times annually, receiving two-month refills with a four-month refill over year-end. Blood was drawn at one AC visit with a clinical assessment at the next. Intervention ACs met twice annually receiving six-month refills, with an individual blood collection visit before the annual clinical assessment AC visit. The first study visits were in October and November 2017 and participants followed for 27 months. We report retention in care, viral load completion and viral suppression (<400 copies/mL) 24 months after enrolment and calculated intention-to-treat risk differences for the primary outcomes using generalized estimating equations specifying for clustering by AC. RESULTS: Of 2150 participants included in the trial, 977 were assigned to the intervention arm (40 ACs) and 1173 to the SoC (48 ACs). Patient characteristics at enrolment were similar across groups. Retention in care at 24 months was similarly high in both arms: 93.6% (1098/1173) in SoC and 92.6% (905/977) in the intervention arm, with a risk difference of -1.0% (95% CI: -3.2 to 1.3). The intervention arm had higher viral load completion (90.8% (999/1173) versus 85.1% (887/977)) and suppression (87.3% (969 /1173) versus 82.6% (853/977)) at 24 months, with a risk difference for completion of 5.5% (95% CI: 1.5 to 9.5) and suppression of 4.6% (95% CI: 0.2 to 9.0). CONCLUSIONS: Intervention AC patients receiving six-month ART refills showed non-inferior retention in care, viral load completion and viral load suppression to those in SoC ACs, adding to a growing literature showing good outcomes with extended ART dispensing intervals.

'Only twice a year': a qualitative exploration of 6-month antiretroviral treatment refills in adherence clubs for people living with HIV in Khayelitsha, South Africa.

OBJECTIVE: Longer intervals between routine clinic visits and medication refills are part of patient-centred, differentiated service delivery (DSD). They have been shown to improve patient outcomes as well as optimise health services-vital as 'universal test-and-treat' targets increase numbers of HIV patients on antiretroviral treatment (ART). This qualitative study explored patient, healthcare worker and key informant experiences and perceptions of extending ART refills to 6 months in adherence clubs in Khayelitsha, South Africa. DESIGN AND SETTING: In-depth interviews were conducted in isiXhosa with purposively selected patients and in English with healthcare workers and key informants. All transcripts were audio-recorded, transcribed and translated to English, manually coded and thematically analysed. The participants had been involved in a randomised controlled trial evaluating multi-month ART dispensing in adherence clubs, comparing 6-month and 2-month refills. PARTICIPANTS: Twenty-three patients, seven healthcare workers and six key informants. RESULTS: Patients found that 6-month refills increased convenience and reduced unintended disclosure. Contrary to key informant concerns about patients' responsibility to manage larger quantities of ART, patients receiving 6-month refills were highly motivated and did not face challenges transporting, storing or adhering to treatment. All participant groups suggested that strict eligibility criteria were necessary for patients to realise the benefits of extended dispensing intervals. Six-month refills were felt to increase health system efficiency, but there were concerns about whether the existing drug supply system could adapt to 6-month refills on a larger scale. CONCLUSIONS: Patients, healthcare workers and key informants found 6-month refills within adherence clubs acceptable and beneficial, but concerns were raised about the reliability of the supply chain to manage extended multi-month dispensing. Stepwise, slow expansion could avoid overstressing supply and allow time for the health system to adapt, permitting 6-month ART refills to enhance current DSD options to be more efficient and patient-centred within current health system constraints.