Important Additional Information and Where to Find It
In connection with the proposed transaction, Indivior Pharmaceuticals, Inc. (“Indivior”) intends to file with the United States Securities and
Exchange Commission (“SEC”) a registration statement on Form S-4, which will include a document that serves as a prospectus of Indivior and a joint proxy statement of Indivior and Supernus
Pharmaceuticals, Inc. (“Supernus”) (the “joint proxy statement/prospectus”). Each party also plans to file other relevant documents with the SEC regarding the proposed transaction. INVESTORS AND SECURITY HOLDERS ARE URGED TO
READ THE JOINT PROXY STATEMENT/PROSPECTUS AND OTHER RELEVANT DOCUMENTS FILED WITH THE SEC WHEN THEY BECOME AVAILABLE, BECAUSE THEY WILL CONTAIN IMPORTANT INFORMATION ABOUT THE PROPOSED TRANSACTION. A definitive joint proxy statement/prospectus will
be sent to Indivior’s stockholders and Supernus’ stockholders. Investors and securityholders may obtain a free copy of the joint proxy statement/prospectus (if and when it becomes available) and other relevant documents filed by Indivior
and Supernus with the SEC at the SEC’s website at www.sec.gov. Copies of the documents filed by Indivior with the SEC will be available free of charge on Indivior’s website at www.indivior.com or by contacting Indivior’s Investor
Relations at InvestorRelations@indivior.com. Copies of the documents filed by Supernus with the SEC will be available free of charge on Supernus’ website at www.supernus.com.
No Offer or Solicitation
This communication and the
information contained herein is for informational purposes only and does not constitute an offer to sell or the solicitation of an offer to buy or exchange any securities, or a solicitation of any vote or approval, nor shall there be any sale of
securities in any jurisdiction in which such offer, solicitation or sale would be unlawful prior to registration or qualification under the securities laws of any such jurisdiction. This communication does not constitute a prospectus or prospectus
equivalent document. No offer of securities shall be made except by means of a prospectus meeting the requirements of Section 10 of the Securities Act of 1933, as amended.
Participants in the Solicitation
Indivior and Supernus
and their respective directors, executive officers and other members of management and employees may be deemed to be participants in the solicitation of proxies in respect of the proposed transaction. Information about directors and executive
officers of Indivior is available in the Indivior proxy statement for its 2026 Annual Meeting, which was filed with the SEC on March 27, 2026. Information about directors and executive officers of Supernus is available in the Supernus proxy
statement for its 2026 Annual Meeting, which was filed with the SEC on April 30, 2026. Other information regarding the participants in the proxy solicitation and a description of their direct and indirect interests, by security holdings or
otherwise, will be contained in the joint proxy statement/prospectus and other relevant materials filed with the SEC regarding the proposed transaction when they become available. Investors should read the joint proxy statement/prospectus carefully
when it becomes available before making any voting or investment decisions. Investors may obtain free copies of these documents from Indivior and Supernus as indicated above.
Forward-Looking Statements
This communication contains
forward-looking statements within the meaning of the U.S. Private Securities Litigation Reform Act of 1995 and other federal securities laws. From time to time, oral or written forward-looking statements may also be included in other information
released to the public. These forward-looking statements are intended to provide Supernus’s and Indivior’s respective management’s current expectations or plans for our future operating and financial performance, based on
assumptions currently believed to be valid. Words such as “anticipate,” “believe,” “estimate,” “expect,” “intend,” “plan,” “project,” “may,”
“will,” “would,” “could,” “should,” and similar expressions are intended to identify forward-looking statements, although not all forward-looking statements contain these words. All forward-looking
statements involve risks, uncertainties and other factors that may cause actual results to differ materially from those expressed or implied in the forward-looking statements. These statements, including statements regarding the proposed merger of
equals of Supernus and Indivior, the expected timing of the closing, and the anticipated benefits and prospects of the combined company, are based on management’s current expectations and are subject to risks and uncertainties that could cause
actual results to differ materially, including, among others: the risk that the proposed merger may not be completed in a timely manner or at all; the failure to obtain the required approvals of Supernus’ or Indivior’s stockholders; the
failure or delay in obtaining required regulatory approvals, or the