Basically Amarin appears to have filed composition of matter patent Link 1 , Link 2 as an extension of 2001(12-14-2001) granted patent . This is done in case where a new patent filing is some what of an obvious variation and would not be patentable over 1st patent (double-patenting). By filing terminal disclaimer, since Amarin owns the 1st granted patent, they would get the claims (still not sure if further prosecution is required or claims would be granted) in second filing, but the patent period would be from the time of granted patents, in this case 2001(12-14-2001 ). The terminal disclaimer was approved by uspto. I consider this as minor positive(it appears nothing is conclusive yet if claim would actually be granted as prosecution is not final on this yet?), as this filing, among other filings, gives a chance to purportedly extend exclusivity of AMR101 to 2021, at the minimum.
The 2 granted patents general claim is for "preferably at least 95%, is in the form of EPA and where less than 5%, and preferably less than 3%, is in the form of DHA is provided for the treatment of a psychiatric or central nervous disorder"
The new patent filing just claims on "similar" composition of matter (no method of use at least in the claims).Link Reader's thoughts are welcome.
Check the below links
-> What is terminal disclaimer
-> Read page 15 of this
-> Granted patents(listed under Laxdale which Amarin acquired) Link(812) Link(077)
-> Pending patent application Link 1
-> Terminal disclosure request from amarin Link