13D Filing: PTV Sciences II LP and Apollo Endosurgery Inc. (APEN)

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

SCHEDULE 13D

UNDER THE SECURITIES EXCHANGE ACT OF 1934

(Amendment No. 1)*

Apollo
Endosurgery, Inc.

(Name of Issuer)

Common Stock

(Title of
Class of Securities)

03767D 108

(CUSIP Number)

Matthew
Crawford

PTV Healthcare Capital

3600 N. Capital of Texas Hwy, Suite B180

Austin, TX 78746

Telephone: (512) 872-4000

(Name, Address and Telephone Number of Person Authorized to Receive Notices and Communications)

September 12, 2017

(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. ☐

Note: Schedules filed in paper format shall include a signed original and five copies of the schedule, including all exhibits. See §240.13d-7 for
other parties to whom copies are to be sent.

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 (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).

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Introductory Note:

This Amendment No. 1 to Schedule 13D (Amendment No. 1) is being filed as an amendment to the statement on Schedule 13D relating to the
common stock, par value $0.001 per share (the Common Stock), of Apollo Endosurgery, Inc. (formerly known as Lpath, Inc.), a Delaware corporation (the Issuer), as filed with the Securities and Exchange Commission (the
SEC) on January 9, 2017 (the Prior Schedule 13D).

All capitalized terms not otherwise defined herein shall have the meanings
ascribed to the terms in the Prior Schedule 13D. The Prior Schedule 13D is hereby amended and supplemented as follows and, except as expressly amended below, the Prior Schedule 13D remains in full force and effect.

PTV Sciences II, L.P. (PTV II)

PTV IV, L.P. (PTV IV)

PTV Special Opportunities I, L.P. (PTV SO)

PTV Evergreen Fund, L.P. (PTV EG)

Pinto Technology Ventures GP II, L.P. (PTV GP II)

PTV GP IV, L.P. (PTV GP IV)

PTV GP SO I, L.P. (PTV GP SO)

PTV GP Evergreen (PTV GP EG)

Pinto TV GP Company LLC (PTV GP Management II)

PTV GP III Management, LLC (PTV GP Management IV)

Matthew S. Crawford (Crawford)

Rick D. Anderson (Anderson)

The Reporting Persons expressly disclaim status as a group for purposes of this Schedule 13D.

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Immediately prior to the effectiveness of the Merger,
PTV II, PTV IV and PTV SO (collectively, the PTV Funds) held 38,237,371, 23,430,184 and 10,531,550 shares of common stock of Original Apollo (the Original Apollo Shares), which shares were acquired (a) through conversion
of Original Apollo preferred stock, conversion of Original Apollo unsecured subordinated convertible promissory notes and net exercise of warrants to acquire Original Apollo stock immediately prior to the Merger and (b) by the purchase of
Original Apollo common stock by PTV IV on December 29, 2016. The aggregate purchase prices paid by PTV II, PTV IV and PTV SO, respectively, in connection with the original acquisition of such Original Apollo securities were $26,635,176.20,
$28,288.791.63 and $10,358,767.61.

Pursuant to the Merger Agreement, the Merger Sub merged with and into Original Apollo, with Original Apollo continuing
after the merger as the surviving corporation and a wholly-owned subsidiary of the Issuer. In connection with the Merger, each of the Original Apollo Shares was cancelled and extinguished and converted into the right to receive shares of Common
Stock of the Issuer. Following a 1-for-5.5 reverse split of the Issuers Common Stock effected immediately following consummation of the Merger, PTV II held 2,199,186 shares of Common Stock, PTV IV held 1,347,565 shares of Common Stock and
PTV SO held 605,712 shares of Common Stock.

On July 25, 2017, PTV EG, Crawford and Anderson purchased 1,090,909 shares of Common Stock, 45,454
shares of Common Stock and 45,454 shares of Common Stock, respectively, at a price of $5.50 per share in connection with the underwritten public offering of 5,689,090 shares of the Issuers Common Stock (the Offering).

On September 5, 2017, PTV EG purchased 41,000 shares of Common Stock at a price of $4.04 per share. On September 12, 2017, PTV EG purchased 135,000
shares of Common Stock at a price of $3.85 per share. Each of the September 2017 purchases was effected as an open market transaction on the NASDAQ National Market.

The source of such funds used by PTV II, PTV IV, PTV SO and PTV EG (collectively, the PTV Funds) was capital contributions by the partners of the
respective PTV Funds. The source of funds used by Crawford and Anderson was personal funds.

The Common Stock of the Issuer acquired by the PTV Funds were acquired solely
for investment purposes. Subject to applicable legal requirements, one or more of the Reporting Persons may purchase additional securities of the Issuer from time to time in open market or private transactions, depending on its evaluation of the
Issuers business, prospects and financial condition, the market for the Issuers securities, other developments concerning the Issuer, the reaction of the Issuer to the Reporting Persons ownership of the Issuers securities,
other opportunities available to the Reporting Persons, and general economic, money market and stock market conditions. In addition, depending upon the factors referred to above, the Reporting Persons may dispose of all or a portion of their
securities of the Issuer at any time. Each of the Reporting Persons reserve the right to increase or decrease its holdings on such terms and at such times as each may decide.

Each of Crawford and Anderson is a member of the Board of Directors of the Issuer and is also a manager of PTV GP Management II and PTV GP Management IV.
Furthermore, Anderson serves as a member of the nominating and governance committee of the Issuers Board of Directors, in which role Anderson is expected to be involved from time to time in the evaluation of the capabilities of existing
directors of the Issuer and the recommendation to the Board of candidates for service as additional or replacement directors of the Issuer.

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Other than as described above in this Item 4, none of the Reporting Persons have any plan or proposal
relating to or that would result in: (a) the acquisition by any person of additional securities of the Issuer or the disposition of securities of the Issuer; (b) an extraordinary corporate transaction, such as a merger, reorganization or
liquidation, involving the Issuer or any of its subsidiaries; (c) a sale or transfer of a material amount of assets of the Issuer or any of its subsidiaries; (d) any change in the present board of directors or management of the Issuer,
including any plans or proposals to change the number or terms of directors or to fill any existing vacancies on the board; (e) any material change in the present capitalization or dividend policy of the Issuer; (f) any other material
change in the Issuers business or corporate structure; (g) any changes in the Issuers charter, by-laws or instruments corresponding thereto or other actions which may impede the acquisition of control of the Issuer by any person;
(h) causing a class of securities of the Issuer to be delisted from a national securities exchange or to cease to be authorized to be quoted in an inter-dealer quotation system of a registered national securities association; (i) a class
of equity securities of the Issuer becoming eligible for termination of registration pursuant to Section 12(g)(4) of the Exchange Act; or (j) any action similar to those enumerated above.

The following information with respect to the ownership of the
Common Stock of the Issuer by the Reporting Persons is provided as of September 19, 2017:

PTV GP Management II is the sole general partner of PTV GP II, which is the sole general partner of PTV II. PTV GP Management II and PTV GP II
own no securities of the Issuer directly and share power to vote and dispose of the shares held by PTV II.

PTV GP Management IV is
(i) the sole general partner of PTV GP IV, which is the sole general partner of PTV IV, (ii) the sole general partner of PTV GP SO, which is the sole general partner of PTV SO, and (iii) the sole general partner of PTV GP EG, which is
the sole general partner of PTV EG. PTV GP Management IV and PTV GP IV own no securities of the Issuer directly and share power to vote and dispose of the shares held by PTV IV. PTV GP Management IV and PTV GP SO own no securities of the Issuer
directly and share power to vote and dispose of the shares held by PTV SO. PTV GP Management IV and PTV GP EG own no securities of the Issuer directly and share power to vote and dispose of the shares held by PTV EG.

Crawford and Anderson are managers of PTV GP Management II and PTV GP Management IV. Accordingly, Crawford and Anderson may be deemed to share
power to vote and dispose of the shares held by PTV II, PTV IV and PTV SO (collectively, the PTV Funds).

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The information provided in Item 3 is hereby incorporated by reference.

Investor Rights Agreement

Original Apollo, the PTV Funds
and certain other holders of the Issuers securities (are party to that certain Third Amended and Restated Investors Rights Agreement dated as of September 8, 2016 (the Rights Agreement). The registration rights of the
stockholders provided under the Rights Agreement survived the Merger. Pursuant to the Rights Agreement, the PTV Funds and certain other holders of the Issuers common stock have been granted registration rights and certain other standard
expense reimbursement and indemnification rights for the benefit of the PTV Funds and certain other investors. The foregoing rights terminate on the fourth anniversary of the Issuers initial public offering. The foregoing description of the
Rights Agreement is only a summary and is qualified in its entirety by reference to the complete text of the Rights Agreement, which is filed as an exhibit hereto and incorporated by reference herein.

Lock-Up Agreement

The PTV Funds, along with the
Issuers officers, directors (including Crawford and Anderson) and certain of the Issuers other stockholders have agreed with the underwriters of the Offering (the Underwriters), subject to limited exceptions, for a period of
90 days after July 21, 2017, not to offer, sell, contract to sell, pledge, grant any option to purchase, make any short sale or otherwise dispose of, directly or indirectly any shares of Common Stock or any securities convertible into or
exchangeable for the Issuers Common Stock either owned as of July 21, 2017 or thereafter acquired without the prior written consent of the Underwriters. This 90-day period may be extended if (1) during the last 17 days of the
90-day period, the Issuer issues an earnings release or material news or a material event regarding the Issuer occurs or (2) prior to the expiration of the 90-day period, the Issuer announces that it will release earnings results during the
16-day period beginning on the last day of the 90-day period, then the period of such extension will be 18 days, beginning on the issuance of the earnings release or the occurrence of the material news or material event. If after any
announcement described in clause (2) of the preceding sentence, the Issuer announces that it will not release earnings results during the 16-day period, the lock-up period shall expire the later of the expiration of the 90-day period and the
end of any extension of such period made pursuant to clause (1) of the preceding sentence. The Underwriters may, in their sole discretion and at any time or from time to time before the termination of the lock-up period, without notice, release
all or any portion of the securities subject to lock-up agreements.

The foregoing descriptions of the Rights Agreement and the Lockup Agreement are only
summaries and are, in each case, qualified in their entirety by the Rights Agreement and form of Lockup Agreement, filed herewith as exhibits A and B, respectively, each of which are incorporated by reference herein.

Other than as described in this Schedule 13D, to the best of the Reporting Persons knowledge, there are no other contracts, arrangements, understandings
or relationships (legal or otherwise) among the persons named in Item 2 and between such persons and any person with respect to any securities of the Issuer.

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Signatures

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

Date: September 22, 2017

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Exhibit Index

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