Solifenacin Succinate

Multiple ICER ranges presented across four different response definitions: $15,000–$45,000 (no incontinence episodes); $45,000–$75,000 (<8 micturitions/24h); $75,000–$105,000 (no urgency or nocturia episodes). Considerable uncertainty noted due to sensitivity to utility weights.

The PBAC considered that with a condition such as overactive bladder one outcome is likely to be more clinically meaningful than another. The four economic models presented in the submission, each based on a different definition of response raised the question of which cost per QALY should apply. PBAC · 2007

PopulationAdults with overactive bladder and symptoms of urge urinary incontinence, urgency or increased urinary frequency, specifically those in whom treatment with oxybutynin has failed or is not tolerated.

• uncertain clinical benefit in the requested population (patients with oxybutynin failure/intolerance), uncertain cost-effectiveness, clinical trial inclusion criteria did not require prior oxybutynin failure, no subgroup analyses for oxybutynin-experienced patients, inability to enforce the proposed restriction, large placebo effect limiting restriction applicability, uncertainty regarding appropriate outcome definition for economic evaluation, sensitivity of economic models to utility weight assumptions