Figure 1.
A. Primary tree showing decision point between regimens and probability of a positive or negative test given presence or absence of infection. B. Positive test subtree. Individuals begin “on treatment” then move to “off treatment” due to toxicity, non-adherence, or treatment completion. Patients in “off treatment” can develop active disease and move to “TB treatment;” after treatment for active disease, they move to “prior TB.” Age-related mortality and death from TB or toxicity is also included. The negative test subtree is similar to the positive test subtree without the “on treatment” branch. Abbreviations: MZ = moxifloxacin+pyrazinamide, ZEmb = pyrazinamide+ethambutol, MEth = Moxifloxacin+ethionamide, MP = moxifloxacin+PA-824, M = moxifloxacin monotherapy.
Table 1.
Model parameters and utility adjustments, point estimates and ranges for sensitivity analyses.
Table 2.
Base-case estimates for protection, adherence, and toxicity for the six regimens and ranges for sensitivity analyses.
Table 3.
Costs for treating latent MDR-TB infection, point estimates and ranges for sensitivity analyses.
Table 4.
Costs for treating active MDR-TB, point estimates and ranges for sensitivity analyses.
Figure 2.
Cost-effectiveness plot for six regimens plus the “no treatment” strategy.
Superior regimens are lower in cost (toward the left) and greater in efficacy (toward the top). Incremental cost-effectiveness ratios (ICERs) are shown for the two most effective regimens referenced to the strategy of “no treatment.” Abbreviations: MZ = moxifloxacin/pyrazinamide, ZEmb = pyrazinamide/ethambutol, MEth = moxifloxacin/ethionamide, MP = moxifloxacin/PA-824, M = moxifloxacin monotherapy. ICER = incremental cost-effectiveness ratio in dollars per quality-adjusted life-year.
Table 5.
Lifetime costs and quality-adjusted life-years (QALY) for all regimens, efficacy predicted by murine model: MP>MZ>>MEmb>MEth = Isoniazid>M = ZEmb.
Table 6.
Lifetime costs and quality-adjusted life-years (QALY) for all regimens, efficacy predicted by murine model: MP>MZ>>MEmb>MEth = Isoniazid>M = ZEmb.
Figure 3.
Strategy graph of efficacy vs. toxicity.
Solid lines indicate thresholds (“isoclines”) for indifference given monthly drug costs of $129 (pyrazinamide/ethambutol), $181 (moxifloxacin/ethambutol), and $404 (moxifloxacin/ethionamide) per month. Shaded area indicates combinations of toxicity and efficacy for which drug treatment is cost-effective compared to the “no treatment” strategy beneath each of these isoclines. Dotted lines indicate the base-case estimates for efficacy and toxicity of moxifloxacin/ethambutol.