Exhibit 99.1
Dear [Business Partner],
Earlier this week we announced that
we have entered into a definitive agreement for Icosavax to be acquired by AstraZeneca. The press release is attached. This is a transformative step in our path to leverage our innovative VLP platform technology to make vaccines that meaningfully
impact human health.
Icosavax and AstraZeneca have a shared ambition to transform prevention against infectious diseases, and together our goal is to
advance Icosavaxs lead program IVX-A12 as well as the Icosavax pipeline.
The transaction is expected to
close in the first quarter of 2024, subject to Icosavax shareholders tendering a sufficient number of shares, receipt of certain regulatory approvals, and satisfaction of other customary closing conditions. Until the transaction closes, Icosavax
will remain an independent company and will continue to operate as such.
We value our relationship with [you / your team], and we are sure you have
several questions about what this means for our ongoing business with [you / your company]. Until closing, we will continue to operate business-as-usual, and any
decisions made on the ongoing business operations will be independent decisions of Icosavax. Immediately following the closing of the transaction, we will be forming an Integration Team and will be reaching out to inform all business partners if and
when there are any changes in relevant business plans or ongoing activities.
Please note, our team will be unable to speak to details of this transaction
outside of what is in the public domain. In the meantime, we appreciate your patience and continued support in advancing the Icosavax pipeline and business objectives.
Best,
[insert name]
* * *
Additional Information and Where to Find It
The tender
offer described above has not yet commenced. This communication is not an offer to buy nor a solicitation of an offer to sell any securities of Icosavax, Inc. The solicitation and the offer to buy shares of Icosavaxs common stock will only be
made pursuant to a tender offer statement on Schedule TO, including an offer to purchase, a letter of transmittal and other related materials, that AstraZeneca PLC, AstraZeneca Finance and Holdings Inc. and Isochrone Merger Sub Inc. (Merger Sub), a
wholly owned indirect subsidiary of AstraZeneca PLC, intend to file with the Securities and Exchange Commission (SEC). In addition, Icosavax will file with the SEC a Solicitation/Recommendation Statement on Schedule
14D-9 with respect to the tender offer. Once filed, investors will be able to obtain a free copy of these materials and other documents filed by AstraZeneca, Merger Sub and Icosavax with the SEC at the website
maintained by the SEC at www.sec.gov. Investors may also obtain, at no charge, any such documents filed with or furnished to the SEC by Icosavax under the Investors & News section of Icosavaxs website at www.icosavax.com.