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. THIS ANNOUNCEMENT D

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.

THIS ANNOUNCEMENT DOES NOT CONSTITUTE AN ANNOUNCEMENT

OF A FIRM INTENTION TO MAKE AN OFFER UNDER RULE 2.7 OF THE CITY CODE ON TAKEOVERS AND MERGERS ("THE CODE"). THERE CAN BE NO

CERTAINTY THAT AN OFFER WILL BE MADE.

THIS ANNOUNCEMENT CONTAINS INSIDE INFORMATION.

Poolbeg Pharma plc ("Poolbeg") and

HOOKIPA Pharma Inc. ("HOOKIPA")

Update on Potential Combination of Poolbeg and

Further to the announcement on 2 January 2025

(the "2.4 Announcement") and the update on the potential combination of Poolbeg and HOOKIPA announced on 7 January 2025,

the following amendment has been made regarding Gilead Sciences Inc.'s ("Gilead") participation in the proposed

concurrent Fundraise.

Gilead has indicated its intention to vote consistent

with the HOOKIPA Board's recommendation if a formal offer were to be made and to participate in the proposed concurrent Fundraise in an

amount up to $8.7495 million, consistent with its current contractual obligations.

All discussions relating to the Potential Combination

to date have been non-binding and on a non-exclusive basis, and there can be no assurance that a firm offer will be made or that any transaction

Capitalised terms used but not defined in this

announcement have the same meanings given to them in the 2.4 Announcement.

In accordance with Rule 30.4 of the Code,

a copy of this announcement will be available on the Company's website - https://www.poolbegpharma.com/about/investors/rns-news/

and Hookipa's website - ir.hookipapharma.com/potential-combination - by 12 noon on 13 January 2025.

The content of the website referred to in this

announcement is not incorporated into and does not form part of this announcement.

Important Information

This announcement is not intended to, and does

not, constitute or form part of any offer, invitation or the solicitation of an offer to purchase, otherwise acquire, subscribe for, sell

or otherwise dispose of, any securities whether pursuant to this announcement or otherwise.

The distribution of this announcement in jurisdictions

outside the United Kingdom may be restricted by law and therefore persons into whose possession this announcement comes should inform

themselves about, and observe such restrictions. Any failure to comply with the restrictions may constitute a violation of the securities

law of any such jurisdiction.

Cavendish Capital Markets Limited ("Cavendish"),

which is authorised and regulated by the Financial Conduct Authority for investment business activities, is acting exclusively as financial

adviser to Poolbeg Pharma plc in relation to the matters set out in this announcement and is not acting for any other person in relation

to such matters. Cavendish will not be responsible to anyone other than Poolbeg Pharma plc for providing the protections afforded

to its clients or for providing advice in connection with any matters referred to in this announcement or otherwise.

Shore Capital and Corporate Limited and Shore

Capital Stockbrokers Limited (together, "Shore Capital"), which are authorised and regulated in the United Kingdom

by the Financial Conduct Authority, are acting exclusively for Poolbeg Pharma plc and no one else in relation to the matters set out in

this announcement and will not be responsible to anyone other than Poolbeg for providing the protections offered to clients of Shore Capital

or for providing advice in relation to the matters referred to herein.

J&E Davy Unlimited Company ("Davy"),

which is authorised and regulated in Ireland by the Central Bank of Ireland and in the United Kingdom by the Financial Conduct Authority,

is acting as broker exclusively for Poolbeg Pharma plc and no one else in relation to the matters set out in this announcement and will

not be responsible to anyone other than Poolbeg for providing the protections offered to clients of J&E Davy or for providing advice

in relation to the matters referred to herein.

Moelis & Company LLC ("Moelis")

is acting as financial adviser to HOOKIPA in connection with the matters set out in this announcement and for no one else and will not

be responsible to anyone other than HOOKIPA for providing the protections afforded to its clients nor for providing advice in relation

to the matters set out in this announcement. Neither Moelis nor any of its subsidiaries, branches or affiliates and their respective directors,

officers, employees or agents owes or accepts any duty, liability or responsibility whatsoever (whether direct or indirect, whether in

contract, in tort, under statute or otherwise) to any person who is not a client of Moelis in connection with this announcement, any statement

contained herein or otherwise.

Canaccord Genuity LLC ("Canaccord")

is acting as financial adviser to Poolbeg Pharma plc in connection with the matters set out in this announcement and for no one else and

will not be responsible to anyone other than Poolbeg for providing the protections afforded to its clients nor for providing advice in

relation to the matters set out in this announcement. Neither Canaccord nor any of its subsidiaries, branches or affiliates and their

respective directors, officers, employees or agents owes or accepts any duty, liability or responsibility whatsoever (whether direct or

indirect, whether in contract, in tort, under statute or otherwise) to any person who is not a client of Canaccord in connection with

this announcement, any statement contained herein or otherwise.

Oppenheimer & Co. Inc. ("Oppenheimer")

is HOOKIPA's placement agent in connection with the Fundraise. Oppenheimer is not a financial advisor for the Potential Combination.

Neither Oppenheimer nor any of its subsidiaries or affiliates or their respective directors, officers, employees or agents owes or accepts

any duty, liability or responsibility whatsoever (whether direct or indirect, whether in contract, in tort, under statute or otherwise)

to any person in connection with this announcement, any statement contained herein or otherwise.

Cautionary Statement Regarding Forward-Looking

This announcement contains "forward-looking"

statements concerning future events. All statements other than statements of historical fact or relating to present facts or current conditions

are forward-looking statements, including all statements related to the potential terms and effects of the Potential Combination and any

statements regarding guidance and statements of a general economic or industry-specific nature.

These forward-looking statements can be identified

by the fact that they do not relate only to historical or current facts. These statements are based on assumptions and assessments made

by HOOKIPA and Poolbeg in light of their discussions to date and their perception of historical trends, current conditions, future developments

and other factors they believe appropriate, and therefore are subject to risks and uncertainties which could cause actual outcomes and

results to differ materially from those expressed or implied by those forward-looking statements.

Forward-looking statements often use forward-looking

or conditional words such as "anticipate", "target", "expect", "forecast", "estimate",

"intend", "plan", "goal", "believe", "hope", "aim", "will",

"continue", "may", "can", "would", "could" or "should" or other

words of similar meaning or the negative thereof. Forward-looking statements include statements relating to the following: (i) the

potential terms of the Potential Combination; (ii) the potential impacts of the Potential Combination; (iii) the outcomes of

due diligence and ongoing negotiations and whether a firm offer will be made or the parties are otherwise able to reach binding agreement

on terms; (iv) the ability of the parties to satisfy (or waive) conditions to the consummation of the Potential Combination; (v) adverse

effects on the market price of HOOKIPA's or Poolbeg's stock prices or operating results as a result of the announcement of

the Potential Combination or failure to agree to binding terms or to otherwise consummate the Potential Combination; (vi) the effect

of the announcement or pendency of the Potential Combination on HOOKIPA's or Poolbeg's business relationships, operating results

and businesses generally; (vii) future capital expenditures, expenses, revenues, economic performance, synergies, financial conditions,

market growth, losses and future prospects; and (viii) business and management strategies and the expansion and growth of the operations

of the Combined Group. There are many factors which could cause actual results to differ materially from those expressed or implied in

forward looking statements. Among such factors are changes in the global, political, economic, business, competitive, market and regulatory

forces, future exchange and interest rates, changes in tax rates and future business combinations or disposals.

These forward-looking statements are not guarantees

of future outcomes or performance and are based on numerous assumptions. By their nature, these forward-looking statements involve known

and unknown risks and uncertainties because they relate to events and depend on circumstances that will occur in the future. No assurance