To answer your questions, the reference to gAczone (Dapsone) is the generic version, both 5 and 7.5%, not the branded product that Mayne Pharma markets in the US and unless a manufacturer is able to circumvent the wholesalers and the PBMs their profits are non existent. Just 3 wholesalers in the US hold 95% of all generics distributed in the US and unless your product is the most competetive on price and gives them the best returns, it doesn't hit the shelves of pharmacies.
Mayne has a long and sad history of marketing generics in the US, having made over 1billion $ worth of losses over the last 8 years and although they are still a small part of their portfolio, they're now loss leaders in a wide range of branded and generic dermatologics to attract business from prescribers for the more profitable branded products in their portfolio. (ie they sell the generics at a loss to attract business for their other branded products)
Since the US government lifted the rules on number of generics and fast tracked approvals from the FDA, companies in this space have struggled , have a look at the share price of the biggest of them all TEVA $70 in 2015 down to $15 now.
Snapshot from Mayne Pharma's 2022 AGM
