Table 1. Key regimen properties to be modelled, as relevant to the BMGF product development portfolio.
We modelled the impact of such an ‘idealised’ pan-TB regimen in India; we also modelled the impact of a ‘less-than-ideal’ future regimen, that meets all but one of these criteria.
| Pan-TB regimen property | Mechanism or rationale | Modelled effect |
|---|---|---|
| 1. Treatment initiation | Simplified regimens, without need for DST, minimise opportunities for initial loss to followup, between diagnosis and treatment initiation | Treatment initiation rates in public sector increased to assumed 95% 1 |
| 2. Treatment success for drug susceptible patients | Shorter, safer regimens enable more patients to successfully complete treatment without side effects | Assume 2 month regimen duration. Conservatively, assume same hazard rate of loss-to-followup as with current first-line therapy. Owing to shorter duration, treatment completion increases to 95% 1 |
| 3. Forgiveness of missed doses | Risk of relapse after treatment success increases substantially with poor adherence to medication intake [18]. New regimens with low risk could be more ‘forgiving’ of poor adherence. | Assume that recurrence rates for both drug-susceptible and RR-TB are halved relative to those on current first-line therapy, independent of treatment completion (i.e., reducing efficacy-effectiveness gap by half) 1,2 |
| 4. Treatment success in RR-TB patients | Owing to use of new molecules, future regimen would be equally effective in those sensitive and resistant to current first-line regimens | Treatment outcomes in RR-TB assumed to be equivalent to those in drug susceptible TB 1 |
1 See S2 Table in S1 Appendix for baseline values for these outcomes under current regimens.