INTRODUCTION
This supplement amends and supplements the Allena Pharmaceuticals, Inc. Proxy Statement dated May 24, 2022 (the Proxy Statement). We refer to
this supplement, together with the enclosed Notice of Special Meeting of Stockholders dated July 13, 2022, as the Supplement). This Supplement is intended to be read in conjunction with our Proxy Statement, and therefore does not
contain all of the information that may be important to you in deciding how to vote on the matters to be considered at the Special Meeting. To the extent information in this Supplement differs from, updates or conflicts with information contained in
the Proxy Statement, the information in this Supplement is the more current information.
UPDATE TO QUESTIONS AND ANSWERS
ABOUT THE SPECIAL MEETING OF STOCKHOLDERS
This Update to Questions and Answers About the Special Meeting of Stockholders summarizes material changes
to the information contained in the Proxy Statement. As this Update to Questions and Answers About the Special Meeting of Stockholders may not contain all of the information that may be important to you, we encourage you to read carefully the entire
Proxy Statement together with this Supplement. The items in this Update to Questions and Answers About the Special Meeting of Stockholders include page references directing you to a more complete description of the applicable topic in the Proxy
Statement.
The following information supplements and, where applicable, replaces the corresponding information under the heading Questions and
Answers About the Special Meeting of Stockholders beginning on page 1 of the Proxy Statement.
The Special Meeting will be held August 4,
2022, at 9:00 a.m., Eastern Time via live webcast. Prior registration to attend the Special Meeting at www.proxydocs.com/ALNA is required by 5:00 p.m. Eastern Time on August 3, 2022 (the Registration Deadline).
In the Proxy Statement and this Supplement, we sometimes refer to Allena Pharmaceuticals, Inc. and its subsidiaries as Allena, the
Company, we, us, or our. In addition, unless the context otherwise requires, references to stockholders are to the holders of our common stock, par value $0.001 per share (Common
Stock), and holders of our Series F Non-Convertible Preferred Stock, par value $0.001 per share (Series F Non-Convertible Preferred Stock or the
Preferred Stock). The shares of Series D Convertible Preferred Stock and Series E Convertible Preferred Stock referenced in the Proxy Statement were not outstanding on the new record date and therefore will not vote on any of the
proposals to be considered at the Special Meeting.
All references to the record date, a holder of record or a stockholder of record refer to the new
record date, July 12, 2022 unless otherwise specified.
Who Can Vote?
The record date to determine the stockholders entitled to notice of and to vote at the Special Meeting is the close of business on July 12, 2022. On the
record date, (i) 107,725,169 shares of Common Stock were issued and outstanding, and (ii) 100 shares of Series F Non-Convertible Preferred Stock, were issued and outstanding and entitled to vote. The shares of
Series D Convertible Preferred Stock and Series E Convertible Preferred Stock referenced in the Proxy Statement were not outstanding on the new record date and therefore will not vote on any of the proposals to be considered at the Special Meeting.
How Many Votes do I Have?
Each holder of record of
our Common Stock is entitled to one vote per share of Common Stock on each matter to be acted upon at the Special Meeting.
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