The legal settlement expires when the last remaining infringed patent expires. As far as I am aware that patent is the Genentech '414 patent licensed to Ipsen, due to expire some time in 2018.
I can't personally see Insmed investing any money in iPlex any time soon. There must be loads of other approved therapies out there for pulmonary conditions which would be far more effective if delivered via inhaled liposomes. But once Ipsen and Genetech no longer have a claim on iPlex I'm sure Insmed will be only too happy to out-license their IP to whoever sees commercialisation potential in iPlex.
Iplex and Increlex are not the same drug. Not even close. The legal settlement was in regard to the
method of production that caused both drugs to be made. INSM infringed on the methodology that
Tercica owned the patten to, and therefor is not permitted to be produced for the indication that IPLEX
was approved for.
Why would they market it as a generic? They can just market it as Iplex. It isn't a duplicate of Increlex at all and is proven to be far, far safer and more effective. This is why they were so adamant about getting Iplex off of the market.