ABOUT THIS PROSPECTUS
This prospectus is part of a registration statement on Form S-3 that
we filed with the U.S. Securities and Exchange Commission (the “SEC”), using a “shelf” registration process.
By using such registration statement, the selling stockholders identified herein may, from time to time, offer and sell (in one
or more transactions as described under “Plan of Distribution”) up to 22,112,775 shares of our common stock underlying
our Series A Convertible Preferred Stock issued in our private placement offering which closed on August 2, 2017. We will not receive
any of the proceeds from the sales of the common stock by the selling stockholders.
This prospectus provides you with a general
description of us and our securities. We may add, update or change in a prospectus supplement any of the information contained
in this prospectus or the documents incorporated by reference. For further information about our business and our securities, you
should refer to the registration statement and the reports incorporated by reference in this prospectus, as described in “Additional
Information” and “Incorporation of Certain Information by Reference”.
You must not rely upon any information or representation
not contained or incorporated by reference in this prospectus. You should rely only on the information contained in this prospectus
and in any prospectus supplement (including in any documents incorporated by reference herein or therein). You should not assume
that the information contained in this prospectus is accurate on any date subsequent to the date set forth on the front of the
document or that any information we have incorporated by reference is correct on any date subsequent to the date of the document
incorporated by reference, even though this prospectus is delivered or securities are sold on a later date. We and the selling
stockholders have not authorized anyone to provide you with any different information. The selling stockholders are offering to
sell our securities, and seeking offers to buy, only in jurisdictions where offers and sales are permitted.
Proteon Therapeutics, Inc. is referred to herein
as “Proteon”, “the Company”, “we”, “us”, and “our”, unless otherwise
specified or the context indicates otherwise.