Aerpio Reports First Quarter 2021 Financial Results and Provides Business Update Ended first quarter 2021 with $39.0 million in cash and cash equivalents Subsequent to

Aerpio Reports First Quarter 2021 Financial Results

and Provides Business Update

CINCINNATI, Ohio, May 17, 2021 Aerpio Pharmaceuticals, Inc. ( Aerpio ) (Nasdaq: ARPO), a

biopharmaceutical company focused on developing compounds that activate Tie2, today reported financial results for the first quarter ended March 31, 2021 and provided a business update.

Key Business Update:

Recent Company Events

First Quarter 2021 Financial Highlights

As of March 31, 2021, cash and cash equivalents totaled $39.0 million, compared to $42.6 million as of December 31, 2020.

Common shares outstanding as of March 31, 2021 totaled approximately 47.4 million. Weighted average common shares (basic and diluted) outstanding for the three months ended March 31, 2021 were 47.3 million.

For the three months ended March 31, 2021, operating expenses totaled $5.6 million, an increase of 36.7% compared to $4.1 million for

the same period in 2020.

Research and development expenses for the three months ended March 31, 2021, increased

approximately $0.4 million, or 21.8%, to $2.2 million from $1.8 million in the three months ended March 31, 2020. This increase was primarily the result of increased expenses associated with our clinical programs

in the three months ended March 31, 2021 compared to the same period in 2020.

General and administrative expenses for the three months

ended March 31, 2021, decreased approximately $0.1 million, or 6.5%, to $2.1 million from $2.3 million, in the three months ended March 31, 2020.

Restructuring expense for the three months ended March 31, 2021of $1.2 million was the result of a reduction of headcount during the first quarter

of 2021. There were no restructuring initiatives executed in the three months ended March 31, 2020.

Net loss attributable to common stockholders for the three months ended March 31,

2021, was $4.4 million, or $0.09 per common share, compared to $3.9 million, or $0.10 per common share, for the same period in 2020.

About Aerpio Pharmaceuticals

Aerpio Pharmaceuticals,

Inc. is a biopharmaceutical company focused on developing compounds that activate Tie2 for indications in which the Company believes that activation of Tie2 may have therapeutic potential. In January 2021, the Company announced that it had

initiated a process to explore and review a range of strategic alternatives focused on maximizing stockholder value from the Company s clinical assets and cash resources. For more information, please visit www.aerpio.com.

Forward Looking Statements

This communication contains

forward-looking statements based upon our current expectations. Forward-looking statements involve risks and uncertainties, and include, but are not limited to, statements about the structure, timing and completion of the proposed

transaction; the combined company s listing on Nasdaq after the closing of the proposed transaction; the business of the combined company, including Aadi s product candidates, the development therefor and the therapeutic potential thereof;

the proposed PIPE and its terms; the opportunity for Aerpio shareholders to receive value from its legacy assets through the proposed contingent value rights, and the intended benefits from the Aspen s collaboration with Gossamer Bio for GB004,

including the continued development of GB004 and the milestone and royalty payments related to the collaboration. Actual results and the timing of events may differ materially from those indicated by these forward-looking statements as a result of

various important factors, including, without limitation: (i) risks associated with Aerpio s ability to obtain the stockholder approval required to consummate the proposed transaction or to complete the PIPE financing, and the timing of

the closing of the proposed transaction, including the risks that a condition to closing would not be satisfied within the expected timeframe or at all or that the closing of the proposed transaction, including the PIPE financing, will not occur

(ii) the response of Aerpio s stockholders to the proposed transaction; (iii) risks related to Aerpio s ability to manage its operating expenses and its expenses associated with the proposed transaction pending closing;

(iv) risks related to the failure or delay in obtaining required approvals from any governmental or quasi-governmental entity necessary to consummate the proposed transaction; (v) the risk that as a result of adjustments to the exchange

ratio, Aerpio stockholders and Aadi stockholders could own more or less of the combined company than is currently anticipated; (vi) risks related to the market price of Aerpio s common stock relative to the exchange ratio;

(vii) unexpected costs, charges, expenditures or expenses resulting from the proposed transaction; (viii) potential adverse reactions or changes to business relationships resulting from the announcement or completion of the proposed

transaction; (ix) Aerpio s ability to retain personnel as a result of the announcement or completion of the proposed transaction; and (x) risks associated with the possible failure to realize certain anticipated benefits of the

proposed transaction, including with respect to future financial and operating results and (xi) the risk that any potential payment of proceeds pursuant to the CVR Agreement may not be distributed at all or result in any value to Aerpio

stockholders. Actual results and the timing of events may differ materially from those anticipated in such forward-looking statements as a result of these risks and uncertainties. These and other risks and uncertainties are more fully described in

periodic filings with the SEC, including the factors described in the section entitled Risk Factors in Aerpio s Annual Report on Form 10-K for the year ended December 31, 2020, which was

filed with the SEC on March 11, 2021 and in other filings that Aerpio makes and will make with the SEC, including those related to the proposed merger transaction with Aadi.

These forward-looking statements are made as of the date of this press release, and the Company assumes no

obligation to update the forward-looking statements, or to update the reasons why actual results could differ from those projected in the forward-looking statements, except as required by law. Investors should consult all the information set forth

herein and should also refer to the risk factor disclosure set forth in the reports and other documents the Company files with the SEC available at www.sec.gov.

Aerpio Pharmaceuticals, Inc.

Pharmaceuticals, Inc.

AERPIO PHARMACEUTICALS, INC.

CONDENSED CONSOLIDATED BALANCE SHEETS

AERPIO PHARMACEUTICALS, INC.

CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS

(In thousands, except per share amounts)