When is the use of suboptimal treatment in functionally untreatable multi-drug resistant tuberculosis morally permissible?

Multidrug-resistant tuberculosis (MDR-TB) is well recognised as a serious threat to controlling and ending the TB epidemic. Treatment is time-intensive and costly. Current treatment guidelines recommend the use of at least four effective drugs plus pyrazinamide for a period of 18–24 months. There are, however, situations in which this is not feasible. This may be due to severe patterns of drug-resistance, poor tolerance to the medications, or supply chain issues. In this paper, I use the term functionally untreatable MDR-TB to refer to such situations. Patients may be assigned to waiting lists until appropriate medications are available, and many die while awaiting treatment. Clinicians face a serious ethical dilemma in these cases, and some may choose to treat their patients with suboptimal regimens in the interim. While this practice may alleviate symptoms and even cure some patients, it is known to extend drug-resistance, limiting further the availability of efficacious anti-TB medicines. This paper explores the relevant ethical considerations faced by clinicians providing MDR-TB treatment, and how this differs from formal ethical principles and guidance. It outlines extreme situations in which suboptimal regimens may be considered, and requisite conditions to be fulfilled by stakeholders for this to be morally permissible.