FORM 8.1(a) & (b) (Opening Position Disclosure)

Full name of discloser:

Alkermes plc

(b)

Owner or controller of interests and short
positions disclosed, if different from 1(a):

The naming of nominee or vehicle
companies isinsufficient. For a trust, the
trustee(s), settlor andbeneficiaries must
be named.

N/A

(c)

Name of offeror/offeree in relation to whose
relevant securities this form relates:

Use a separate form for each offeror/offeree

Avadel
Pharmaceuticals 
plc

(d)

Is the discloser the offeror or the offeree?

OFFEROR

(e) 

Date position held:

The latest practicable date prior to the
disclosure

3 November
2025

(f)  

In addition to the company in 1(c) above, is
thediscloser also making disclosures in
respectof any other party to the offer?

If it is a cash offer or possible cash offer, state
"N/A"

N/A

Details of any interests and short positions (including directors'
and other employee options) of any person acting in concert with
the party making the disclosure:

Party

Class of 
Relevant
Security

Number of 
ordinary
shares held
at midnight
(ET) on
3 November
2025

Percentage 
of total
issued share
capital
(rounded)

55I, LLC

Ordinary 
shares of
US$0.01
each

53

0.0001 %

JPMorgan
Chase Bank,
National
Association

Ordinary 
shares of
US$0.01
each

13,500

0.0139 %

TOTAL

13,553

0.0139 %

Irrevocable commitments and letters of intent should not be included. If
there are no such agreements, arrangements or understandings, state
"none"

None

Full details of any agreement, arrangement or understanding
between the person disclosing and any other person relatingto the
voting rights of any relevant securities under any optionreferred
to on this form or relating to the voting rights or futureacquisition
or disposal of any relevant securities to which anyderivative
referred to on this form is referenced. If none, thisshould be stated. 

None

Is a Supplemental Form 8 attached?   

YES/NO

No

Date of disclosure:

5 November 2025

Contact name:

Sandy Coombs, Alkermes

Telephone number:

+1 781 609 6377

Public disclosures under Rule 8.1 of the Rules must be made to a 
Regulatory Information Service.