Treatment-stopping rule and treatment effect waning
We also considered a scenario with a 2-y treatment-stopping rule, after which the drug costs for the new treatment To avoid these limitations, we used an alternative approach to implement treatment effect waning. For The waning-adjusted hazard function for OS and PFS for the new treatment is given by
where the first term is the Weibull hazard function, 
where 
All other model assumptions and net benefit functions are as above.The expected Weibull survival curves for the scenarios with and without adjustment for treatment effect waning are given in Expected Weibull survival curves for overall survival and progression-free survival for the new treatment and for standard care without adjustment (left) and with adjustment for treatment effect waning (right).