Patient and provider costs of the new BPaL regimen for drug-resistant tuberculosis treatment in South Africa: A cost-effectiveness analysis.

Abstract

Drug-resistant (DR) tuberculosis (TB) is typically characterized by resistance to a single or combination of first- and/or second-line anti-TB agents and commonly includes rifampicin-resistant (RR)-TB, multidrug-resistant (MDR)-TB, pre-extensively drug-resistant (pre-XDR)-TB and XDR-TB. Historically, all variations of DR-TB required treatment with second-line drugs which are less effective and more toxic than first-line options, have a longer treatment duration and are more expensive to both patients and providers. The World Health Organization (WHO) now recommends a new second-line 3-drug 6-month all-oral regimen consisting of bedaquiline, pretomanid, and linezolid referred to as BPaL. We estimate patient and provider costs of DR-TB treatment with BPaL compared to the current standard of care in South Africa. In coordination with South Africa's BPaL clinical access programme (CAP) we conducted an economic evaluation of A) patient costs through a cross-sectional patient cost survey and B) provider costs through a bottom-up costing analysis consisting of a retrospective medical record review (patient resource-use) and top-down financial record review (fixed/shared costs such as overhead). Across both costing perspectives, we compare costs of 1) BPaL, to current standard of care options including the 2) 9-11-month standard short oral regimen (SSOR) and 3) 18-21-month standard long oral regimen (SLOR). Eligible patients included those ≥14 years old with confirmed sputum pulmonary RR/MDR-TB, pre-XDR or XDR-TB. All costs are reported in 2022 United States Dollar (US$). A total of 72 patients were enrolled and completed the patient cost survey (41.7% on BPaL, 16.7% on the SSOR and 41.7% on the SLOR). Mean on-treatment patient costs were lowest among those on BPaL ($56.6) and increased four-fold among those on the SSOR ($228.1) and SLOR ($224.7). Direct medical patient costs were negligible across all treatment regimens, while direct non-medical patient and guardian costs for travel, food and nutritional supplementation accounted for the largest proportion of total costs ($54.6, $227.8 and $224.3 for BPaL, the SSOR and SLOR respectively). In assessing provider costs, a total of 112 medical records were reviewed (37.5%, 41.1% and 21.4% on BPaL, the SSOR and SLOR respectively). Total provider costs for producing a favorable treatment outcome (cured/completed treatment) were similar among those on BPaL ($4,948.7 per patient) and the SSOR ($4,905.6 per patient) with costs increasing substantially among those on the SLOR ($8,919.9 per patient). Based on incremental cost-effectiveness ratios (ICERs), at even the lowest willingness to pay (WTP) threshold, treatment with the new BPaL regimen was more cost-effective than current standard of care treatment options (ICER: $311.4 < WTP: $3,341). When using the newly recommended BPaL regimen, cost to patients decreased by 75% compared to current standard of care treatment options in South Africa. Due in part to higher resource-use within the BPaL CAP offsetting the shorter treatment duration, cost of treatment provision through BPaL and the 9-11-month SSOR were similar. However, when considering cost and treatment outcomes, BPaL was more cost-effective than other standard of care regimens currently available for DR-TB in South Africa.