Under the Securities Exchange Act of 1934
(Amendment No. 6)*

Aerpio Pharmaceuticals, Inc.

(Name of Issuer)

Common Stock, par value $0.0001 per share

(Title of Class of Securities)

00810B105

(CUSIP Number)

Bart Dzikowski

Secretary of the Board

Novartis Bioventures Ltd.

Lichtstrasse 35

CH-4056 Basel, Switzerland

+41 61 324 3714
 (Name, Address and Telephone Number of Person
Authorized to Receive Notices and Communications)

April 21, 2020

(Date of Event Which Requires Filing of this Statement)

If the filing person has previously filed a statement on Schedule 13G to report the acquisition that is the subject of this Schedule 13D, and is filing this schedule because of §§240.13d-1(e), 240.13d-1(f) or 240.13d-1(g), check the following box. o

*                 The remainder of this cover page shall be filled out for a reporting person’s initial filing on this form with respect to the subject class of securities, and for any subsequent amendment containing information which would alter disclosures provided in a prior cover page.

The information required on the remainder of this cover page shall not be deemed to be “filed” for the purpose of section 18 of the Securities Exchange Act of 1934, as amended (“Act”) or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes).

(1)         Based on 40,588,004 shares of Common Stock outstanding as of March 9, 2020, as reported in the Issuer’s Annual Report on Form 10-K filed with the Securities and Exchange Commission (the “SEC”) on March 16, 2020.

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(1)         Based on 40,588,004 shares of Common Stock outstanding as of March 9, 2020, as reported in the Issuer’s Annual Report on Form 10-K filed with the SEC on March 16, 2020.

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Item 1.         Security and Issuer.

This Amendment No. 6 (the “Amendment”) to Schedule 13D amends the Schedule 13D filed by the Reporting Persons (as defined below) with the SEC on March 27, 2017, as previously amended on June 28, 2018,  March 28, 2019,  April 11, 2019, April 29, 2019 and June 7, 2019 (the “Original Schedule 13D” and, together with the Amendment, the “Schedule 13D”) and relates to the common stock, par value $0.0001 per share (the “Common Stock”), of Aerpio Pharmaceuticals, Inc., a Delaware corporation (the “Issuer”).  The address of the Issuer’s principal executive office is 9987 Carver Road, Cincinnati, OH 45242.

As a result of the open market sales reported in Item 5(c) of this Amendment, the percentage of outstanding shares of Common Stock that the Reporting Persons may be deemed to beneficially own was reduced by more than one percent of the Issuer’s shares of Common Stock outstanding since the filing of the Original Schedule 13D.

Except as otherwise described herein, the information contained in the Original Schedule 13D remains in effect. Capitalized terms used but not defined in this Amendment shall have the respective meanings set forth with respect thereto in the Original Schedule 13D.

Item 2.         Identity and Background.

Item 2 of the Original Schedule 13D is hereby amended such that all reference to Schedule I contained within Item 2 and otherwise within the Original Schedule 13D shall refer to the Schedule I included in this Amendment.

Item 3.         Source and Amounts of Funds or Other Consideration.

No changes.

Item 4.         Purpose of Transaction.

The information set forth in Item 5(c) of this Amendment is incorporated herein by reference. Otherwise, there are no changes to the disclosure provided under this Item 4 in the Original Schedule 13D.

Item 5.         Interest in Securities of the Issuer.

(a)                                 As of the date hereof, the Reporting Persons may be deemed, for purposes of Rule 13d-3 of the Act, directly or indirectly, including by reason of their mutual affiliation, to be the beneficial owners of 3,147,667 shares of Common Stock. NBV is a wholly-owned indirect subsidiary of Novartis. Based on 40,588,004 shares of Common Stock outstanding as of March 9, 2020, as reported in the Issuer’s Annual Report on Form 10-K filed with the SEC on March 16, 2020, the Common Stock held by the Reporting Persons constitutes 7.76% of the outstanding shares of Common Stock of the Issuer.

(b)                                 With respect to the number of shares of Common Stock as to which each Reporting Person has:

(i)                                     sole power to vote or to direct the vote with respect to such shares of Common Stock, please see row 7 of the applicable cover sheet to this Amendment for such Reporting Person;

(ii)                                  shared power to vote or to direct the vote with respect to such shares of Common Stock, please see row 8 of the applicable cover sheet to this Amendment for such Reporting Person;

(iii)                               sole power to dispose or direct the disposition of such shares of Common Stock, please see row 9 of the applicable cover sheet to this Amendment for such Reporting Person; and

(iv)                              shared power to dispose or to direct the disposition of such shares of Common Stock, please see row 10 of the applicable cover sheet to this Amendment for such Reporting Person.

(c)                                  Other than the open market sales referred to below or previously reported in the Original Schedule 13D, none of (i) the Reporting Persons or, (ii) to the Reporting Persons’ knowledge, the persons set forth on Schedule I hereto has effected any transaction in the Common Stock during the past 60 days.

On April 21, 2020, the Reporting Persons sold 50,213 shares of Common Stock at a weighted average price of $0.70 per share (price range: $0.65–$0.73).

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On April 20, 2020, the Reporting Persons sold 103,839 shares of Common Stock at a weighted average price of $0.64 per share (price range: $0.60 – $0.67).

On April 17, 2020, the Reporting Persons sold 25,517 shares of Common Stock at a weighted average price of $0.58 per share (price range: $0.56 - $0.60).

On April 16, 2020, the Reporting Persons sold 80,010 shares of Common Stock at a weighted average price of $0.58 per share (price range: $0.54 - $0.62).

On April 15, 2020, the Reporting Persons sold 13,101 shares of Common Stock at a weighted average price of $0.51 per share (price range: $0.50 - $0.54).

On April 14, 2020, the Reporting Persons sold 10,900 shares of Common Stock at a weighted average price of $0.56 per share (price range: $0.55 - $0.59).

On April 13, 2020, the Reporting Persons sold 3,012 shares of Common Stock at a weighted average price of $0.55 per share (price range: $0.54 - $0.56).

On April 9, 2020, the Reporting Persons sold 6,293 shares of Common Stock at a weighted average price of $0.54 per share (price range: $0.54 - $0.55).

On April 8, 2020, the Reporting Persons sold 12,603 shares of Common Stock at a weighted average price of $0.54 per share (price range: $0.54 - $0.56).

On April 7, 2020, the Reporting Persons sold 3,176 shares of Common Stock at a weighted average price of $0.55 per share (price range: $0.54 - $0.55).

On April 6, 2020, the Reporting Persons sold 8,493 shares of Common Stock at a weighted average price of $0.54 per share (price range: $0.53- $0.55).

On April 3, 2020, the Reporting Persons sold 1,418 shares of Common Stock at a weighted average price of $0.53 per share (price range: $0.51- $0.53).

On April 2, 2020, the Reporting Persons sold 9,780 shares of Common Stock at a weighted average price of $0.52 per share (price range: $0.50 - $0.56).

On April 1, 2020, the Reporting Persons sold 1,896 shares of Common Stock at a weighted average price of $0.52 per share (price range: $0.52 - $0.53).

On March 27, 2020, the Reporting Persons sold 4,100 shares of Common Stock at a weighted average price of $0.51 per share (price range: $0.50 - $0.52).

On March 26, 2020, the Reporting Persons sold 1,600 shares of Common Stock at a weighted average price of $0.51 per share (price range: $0.51 - $0.53).

On March 25, 2020, the Reporting Persons sold 5,417 shares of Common Stock at a weighted average price of $0.50 per share (price range: $0.50 - $0.52).

On March 24, 2020, the Reporting Persons sold 6.900 shares of Common Stock at a weighted average price of $0.51 per share (price range: $0.50 - $0.53).

The Reporting Persons undertake to provide the Issuer, any stockholder of the Issuer, or the Staff of the SEC, upon request, full information regarding the number of shares purchased at each separate price within the ranges set forth in this Item 5(c).

(d)                                 Not applicable.

(e)                                  Not applicable.

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Item 6.         Contracts, Arrangements, Understandings or Relationships With Respect to Securities of the Issuer.

No changes.

Item 7.         Material to be Filed as Exhibits.

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Signature

After reasonable inquiry and to the best of the undersigned’s knowledge and belief, the undersigned hereby certify that the information set forth in this statement is true, complete and correct.

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SCHEDULE I

DIRECTORS AND EXECUTIVE OFFICERS OF
NOVARTIS AG AND NOVARTIS BIOVENTURES LTD.

Directors and Executive Officers of Novartis AG

The name, function, citizenship and present principal occupation or employment of each of the directors and executive officers of Novartis AG are set forth below. Unless otherwise indicated below, (i) each occupation set forth opposite an individual’s name refers to employment with Novartis AG and (ii) the business address of each director and executive officer of Novartis AG is Novartis Campus, Lichtstrasse 35, CH-4056, Basel, Switzerland.

I-2

I-3

Exhibit 99.1

Joint Filing Agreement

In accordance with Rule 13d-1(k)(1) promulgated under the Securities Exchange Act of 1934, as amended, the undersigned hereby agree to the joint filing with each other on behalf of each of them of such a statement on Schedule 13D (including amendments thereto) with respect to the Common Stock beneficially owned by each of them of Aerpio Pharmaceuticals, Inc.  This Joint Filing Agreement shall be included as an Exhibit to such Schedule 13D.

IN WITNESS WHEREOF, the undersigned hereby execute this Joint Filing Agreement as of the 22nd day of April, 2020.