NOT FOR RELEASE, PUBLICATION OR DISTRIBUTION IN WHOLE OR IN PART IN, INTO OR FROM ANY JURISDICTION WHERE TO DO SO WOULD CONSTITUTE A VIOLATION OF THE RELEVANT LAWS OR REGULATIONS OF THAT JURISDICTION. [FOR IMMEDIATE RELE

NOT FOR RELEASE, PUBLICATION OR DISTRIBUTION

IN WHOLE OR IN PART IN, INTO OR FROM ANY JURISDICTION WHERE TO DO SO WOULD CONSTITUTE A VIOLATION OF THE RELEVANT LAWS OR REGULATIONS

OF THAT JURISDICTION.

[FOR IMMEDIATE RELEASE]

Avadel Pharmaceuticals Announces that Avadel

Shareholders Approve the Proposed Acquisition by Alkermes

DUBLIN, January 12, 2026 - Avadel Pharmaceuticals

plc (Nasdaq: AVDL), a public limited company incorporated in Ireland ("Avadel" or the "Company")

announces today that, in relation to the previously announced offer for the Company by Alkermes plc, a public limited company incorporated

in Ireland ("Alkermes"), pursuant to which Alkermes will acquire the entire issued and to be issued ordinary share

capital of the Company (the "Proposed Transaction"), the resolutions required to approve the scheme of arrangement

under Chapter 1 of Part 9 of the Irish Companies Act 2014 (the "Scheme") were passed by the requisite majorities at

the scheme meeting of shareholders (the "Scheme Meeting") and the related extraordinary general meeting of shareholders

("EGM") held earlier today.

Full details of the resolutions passed are set

out in the notices of the Scheme Meeting and EGM contained in the definitive proxy statement filed by Avadel with the U.S. Securities

and Exchange Commission ("SEC") on December 3, 2025 (the "Definitive Proxy Statement"). A quorum

was present at each of the Scheme Meeting and the EGM, being five or more registered holders of Avadel shares holding a majority of the

voting power of Avadel shares as of 5.00 p.m. (U.S. Eastern Time) on November 25, 2025, the voting record time for the Scheme Meeting

and the EGM. The final results of voting on each of the proposals submitted are as follows.

At the Scheme Meeting, Avadel shareholders voted

on the proposal described below:

That the Scheme in its original form or with or subject to any modification(s), addition(s) or condition(s) approved or imposed by the

Irish High Court be agreed to (the "Scheme Meeting Proposal")

Avadel shareholders approved the Scheme Meeting

Proposal at the Scheme Meeting with the following results, including the percentage of votes cast for and against the Scheme Meeting Proposal:

In addition, of the 21 shareholders of record

voting on the Scheme Meeting Proposal, 20 shareholders of record, or 95.24% of those voting, voted in favour of the proposal and one shareholder

of record, or 4.76% of those voting, voted against the proposal. Accordingly, the votes cast in favour of the Scheme Meeting Proposal

represented a majority in number of the shareholders of record present and voting, either in person or by proxy, and at least 75% of the

value of the shares voted at the meeting, either in person or by proxy.

The Avadel shares voted in favour of and against

the Scheme Meeting Proposal represented 63.03% and 1.68%, respectively, of the 98,151,471 Avadel shares outstanding as of the voting record

time and entitled to vote at the Scheme Meeting.

At the EGM, Avadel shareholders voted on the proposals

Avadel shareholders approved the Scheme

Approval Proposal at the EGM with the following results, including the percentage of votes cast for and against the Scheme Approval Proposal:

Avadel shareholders approved the Articles

of Association Amendment Proposal at the EGM with the following results, including the percentage of votes cast for and against the Articles

of Association Amendment Proposal:

Avadel shareholders approved the Compensation

Proposal at the EGM with the following results including the percentage of votes cast for and against the Compensation Proposal:

Avadel Pharmaceuticals plc (Nasdaq:

AVDL) is a biopharmaceutical company focused on transforming medicines to transform lives. Avadel's approach includes applying innovative

solutions to the development of medications that address the challenges patients face with current treatment options. Avadel's commercial

product, LUMRYZ , was approved by the U.S. Food & Drug Administration as the first and only once-at-bedtime oxybate

for extended-release oral suspension for the treatment of cataplexy or excessive daytime sleepiness in patients 7 years and older with

narcolepsy. For more information, please visit Avadel's website at www.avadel.com.

Avadel Investor Relations:

CAUTIONARY STATEMENT REGARDING FORWARD-LOOKING

This announcement contains forward-looking statements

within the meaning of the Private Securities Litigation Reform Act of 1995. These forward-looking statements are often identified by words

such as "anticipate," "believe," "intend," "estimate," "expect," "seek,"

"continue," "could," "can," "may," "will," "likely," "depend,"

"should," "would," "plan," "predict," "target," and similar expressions, and

may include references to assumptions and relate to Avadel's future prospects, developments and business strategies, and the Proposed

Transaction. Such forward-looking statements include, but are not limited to, statements relating to the Proposed Transaction involving

Alkermes and Avadel, Avadel's current expectations and estimates about the anticipated benefits of the Proposed Transaction, the

parties' ability to satisfy the conditions to the consummation of the Proposed Transaction and the other conditions set forth in

the transaction agreement between Alkermes and Avadel regarding the Proposed Transaction. Avadel's expectations and beliefs regarding

these matters may not materialize. Actual outcomes and results may differ materially from those contemplated by these forward-looking

statements as a result of uncertainties, risks, and changes in circumstances, including but not limited to risks and uncertainties related

to: (i) the ability of the parties to consummate the Proposed Transaction in a timely manner or at all; (ii) the satisfaction (or waiver)

of conditions to the consummation of the Proposed Transaction; (iii) potential delays in consummating the Proposed Transaction; (iv) the

ability of Avadel to timely and successfully achieve the anticipated benefits of the Proposed Transaction (v) the impact of health pandemics

on the parties' respective businesses and the actions the parties may take in response thereto; (vi) the occurrence of any event,

change or other circumstance or condition that could give rise to the termination of the transaction agreement between Alkermes and Avadel

regarding the Proposed Transaction; (vii) the effect of the pendency of the Proposed Transaction on Avadel's business relationships,

operating results and business generally; (viii) costs related to the Proposed Transaction; and (ix) the outcome of any legal proceedings

that may be instituted against the parties or any of their respective directors or officers related to the transaction agreement between

Alkermes and Avadel regarding the Proposed Transaction or the Proposed Transaction. Additional risks and uncertainties that could cause

actual outcomes and results to differ materially from those contemplated by the forward-looking statements are included under the caption

"Risk Factors" and elsewhere in Avadel's most recent filings with the SEC, including its Annual Report on Form 10-K

for the year ended December 31, 2024 and any subsequent reports on Form 10-Q or Form 8-K filed with the SEC from time to time and available

at www.sec.gov. These documents can be accessed on Avadel's website at https://investors.avadel.com/sec-filings. The forward-looking

statements set out in this announcement are made only as of the date hereof. Avadel assumes no obligation and does not intend to update

these forward- looking statements, except as required by law.

RESPONSIBILITY STATEMENT REQUIRED BY THE

IRISH TAKEOVER RULES

The directors of Avadel accept responsibility

for the information contained in this announcement. To the best of the knowledge and belief of the directors of Avadel (who have taken

all reasonable care to ensure such is the case), the information contained in this announcement is in accordance with the facts and does

not omit anything likely to affect the import of such information.

DEALING DISCLOSURE REQUIREMENTS OF THE IRISH

Under the provisions of Rule 8.3(a) of the Irish

Takeover Rules, any person who is interested' (directly or indirectly) in 1% or more of any class of relevant securities'

of Avadel must make an opening position disclosure' following the commencement of the offer period'. An opening

position disclosure' must contain the details contained in Rule 8.6(a) of the Irish Takeover Rules, including, among other things,

details of the person's interests' and short positions' in any relevant securities' of Avadel.

An opening position disclosure' by a person to whom Rule 8.3(a) applies must be made by no later than 3:30 p.m. (U.S. Eastern

Time) on the day falling ten business days' following the commencement of the offer period'. Relevant persons

who deal in any relevant securities' prior to the deadline for making an opening position disclosure' must instead

make a dealing' disclosure as described below. The offer period in respect of Avadel in relation to the Proposed Transaction

commenced on October 22, 2025.