SUPPLEMENT DATED JUNE 3, 2022 TO THE PROXY STATEMENT
OF
MITHRIL II LP
MITHRIL II GP LP
MITHRIL II UGP LLC
AJAY
ROYAN
PETER THIEL
POLARIS VENTURE PARTNERS V, L.P.
POLARIS VENTURE PARTNERS ENTREPRENEURS FUND V, L.P.
POLARIS VENTURE PARTNERS FOUNDERS FUND V, L.P.
POLARIS VENTURE PARTNERS SPECIAL FOUNDERS FUND V, L.P.
POLARIS PARTNERS IX, L.P.
POLARIS HEALTHCARE TECHNOLOGY OPPORTUNITIES FUND, L.P.
POLARIS VENTURE MANAGEMENT CO. V, L.L.C.
POLARIS PARTNERS GP IX, L.L.C.
POLARIS HEALTHCARE TECHNOLOGY OPPORTUNITIES FUND GP, L.L.C.
TERRANCE MCGUIRE
JONATHAN FLINT
M28
CAPITAL MANAGEMENT LP
MARC ELIA
ADIMAB, LLC
POPULATION
HEALTH EQUITY PARTNERS III, L.P.
POPULATION HEALTH EQUITY PARTNERS III GP, LLC
POPULATION HEALTH EQUITY PARTNERS VII, L.P.
POPULATION HEALTH EQUITY PARTNERS VII GP, LLC
CLIVE A. MEANWELL, M.B., Ch.B, M.D.
CHRISTOPHER COX
TAMSIN
BERRY
DATED APRIL 29, 2022
This
supplement (the Supplement), dated June 3, 2022, to the definitive proxy statement filed by Mithril II, LP, Mithril II GP LP, Mithril II UGP LLC, Ajay Royan, Peter Thiel (all of the forgoing persons, collectively,
Mithril), Polaris Venture Partners V, L.P., Polaris Venture Partners Entrepreneurs Fund V, L.P., Polaris Venture Partners Founders Fund V, L.P., Polaris Venture Partners Special Founders Fund V, L.P., Polaris
Partners IX, L.P., Polaris Healthcare Technology Opportunities Fund, L.P., Polaris Venture Management Co. V, L.L.C., Polaris Partners GP IX, L.L.C., Polaris Healthcare Technology Opportunities Fund GP, L.L.C., Terrance McGuire, Jonathan Flint, M28
Capital Management, LP, Marc Elia, Adimab, LLC, Population Health Equity Partners III, L.P., Population Health Equity Partners III GP, LLC, Population Health Equity Partners VII, L.P., Population Health Equity Partners VII GP, LLC, Christopher Cox,
Clive A. Meanwell and Tamsin Berry (all of the forgoing persons, together with Mithril, the Participants) with the Securities and Exchange Commission (the SEC) on April 29, 2022 (our Proxy
Statement), and the WHITE proxy card accompanying this Supplement, are being furnished to stockholders of Adagio Therapeutics, Inc., a Delaware corporation (Adagio or the Company) by
Mithril in connection with the 2022 annual meeting of stockholders of the Company (including any and all adjournments, postponements, continuations or reschedulings thereof, or any other meetings of stockholders of the Company held in lieu thereof,
the 2022 Annual Meeting), currently scheduled to be held in person on June 22, 2022, at 8:30 a.m. Eastern Time, at the offices of WilmerHale, 60 State Street, Boston, Massachusetts. The Company has set June 2, 2022
(the Record Date) as the new record date for determining stockholders entitled to notice of and to vote their shares of the Companys common stock (the Common Stock) at the 2022 Annual Meeting.
THIS SOLICITATION IS BEING MADE BY THE PARTICIPANTS AND NOT ON BEHALF OF THE ADAGIO BOARD OF DIRECTORS.
This Supplement is dated June 3, 2022 and is first being provided to stockholders on or about June 3, 2022.