Exhibit 10.1

AMARIN CORPORATION PLC

AMENDMENT NO. 1 TO

2011 STOCK INCENTIVE PLAN

The Amarin Corporation plc 2011 Stock Incentive Plan (the “Plan”) is hereby
amended by the Board of Directors of Amarin Corporation plc as follows:

Section 4(a) of the Plan is hereby amended to add the following to the end of
the third sentence thereof:

“; provided, however, that Shares tendered or held back upon exercise of an
Option or settlement of an Award to cover the exercise price or tax withholding
shall not be considered a Lapsed Award.”

such that Section 4(a) of the Plan, as so amended, shall read in its entirety as
follows:

Section 4. Shares Available for Awards

 

  (a) Shares Available. Subject to adjustment as provided in Section 4(c) of the
Plan, the number of Shares in respect of which Awards may be made under this
Plan on any day shall not exceed the sum of (i) 3.5 million Shares, (ii) the
number of Shares that remain available for grants under the 2002 Plan as of the
Effective Date and (iii) the number of Shares subject to grants under the 2002
Plan that are outstanding as of the Effective Date but subsequently become
Lapsed Awards (as defined below) (“the Plan Limit”). Shares to be issued under
the Plan may be either authorized but unissued Shares, or Shares acquired in the
open market or otherwise. If any award over Shares granted under this Plan or
the 2002 Plan expires or is forfeited, surrendered, canceled or otherwise
terminated in whole or in part without Shares being issued (“Lapsed Award”),
then the Shares subject to such Lapsed Award may, at the discretion of the
Committee, be made available for subsequent grants under the Plan; provided,
however, that Shares tendered or held back upon exercise of an Option or
settlement of an Award to cover the exercise price or tax withholding shall not
be considered a Lapsed Award. Notwithstanding the foregoing, the number of
Shares available for granting Incentive Stock Options under the Plan shall not
exceed the ISO Limit, and Options with respect to no more than 3.5 million
Shares may be granted to any one individual Participant during any one calendar
year period.