Looks like the incidence of shingles in the general population is ~3.2/1000, which makes about 1 million cases per year in the US. If we get 10% market penetration that is 100,000 uses per year, say an average of 3 patches each at $30 per results in $100 million annual revenue. Has anyone seen other estimates?
---problem with your estimates is that only 1 in 5 suffer from prolonged pain. Now your down to maybe a 200,000 per year market size. On the upside the treatments may be repeated every 3 to 4 months(thus multiple cycles are possible). And don't forget the carryover group--that continues to suffer from one year to the next.