Aileron Therapeutics : Merger Announcement

Merger Announcement

C O R P O R A T E P R E S E N T A T I O N

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Forward-Looking Statements

This presentation and various remarks we make during this presentation contain forward-looking statements of Aileron Therapeutics, Inc. ("Aileron", the "Company", "we", "our" or "us") within the meaning of the Private Securities Litigation Reform Act of 1995, including statements with respect to: future expectations, plans and prospects for the Company following the consummation of the merger transaction (the "Merger") between the Company and Lung Therapeutics, Inc. ("Lung Tx"); the expected closing of the concurrent private placement; the use of proceeds from the private placement and the sufficiency of the Company's cash resources; stockholder approval of the conversion of the non-voting preferred stock; the initial market capitalization of the Company following the Merger and the benefits of the Merger; and the milestones of the Company; the projected cash runway of the Company; the status and plans for clinical trials, including the timing of data; future product development; and the potential commercial opportunity of LTI-03 and LTI-01. We use words such as "anticipate," "believe," "estimate," "expect," "hope," "intend," "may," "plan," "predict," "project," "target," "potential," "would," "can," "could," "should," "continue," and other words and terms of similar meaning to help identify forward-looking statements, although not all forward-looking statements contain these identifying words. Actual results may differ materially from those indicated by such forward-looking statements as a result of various important factors, including risks and uncertainties related to the ability to recognize the anticipated benefits of the Merger, the outcome of any legal proceedings that may be instituted against the Company following the Merger and related transactions, the ability to obtain or maintain the listing of the common stock of the Company on The Nasdaq Stock Market following the Merger, costs related to the Merger, changes in applicable laws or regulations, the possibility that the Company may be adversely affected by other economic, business, and/or competitive factors, including risks inherent in pharmaceutical research and development, such as: adverse results in the Company's drug discovery, preclinical and clinical development activities, the risk that the results of preclinical studies and early clinical trials may not be replicated in later clinical trials, the Company's ability to enroll patients in its clinical trials, and the risk that any of its clinical trials may not commence, continue or be completed on time, or at all; decisions made by the U.S. FDA and other regulatory authorities, investigational review boards at clinical trial sites and publication review bodies with respect to our development candidates; our ability to obtain, maintain and enforce intellectual property rights for our platform and development candidates; our potential dependence on collaboration partners; competition; uncertainties as to the sufficiency of the Company's cash resources to fund its planned activities for the periods anticipated and the Company's ability to manage unplanned cash requirements; and general economic and market conditions; as well as the risks and uncertainties discussed in the "Risk Factors" section of the Company's Annual Report on Form 10-K for the year ended December 31, 2022, which is on file with the Securities and Exchange Commission, and in subsequent filings that the Company files with the Securities and Exchange Commission. These forward-looking statements should not be relied upon as representing the Company's view as of any date subsequent to the date of this presentation, and we expressly disclaim any obligation to update any forward-looking statements, whether as a result of new information, future events or otherwise, except as required by law.

This presentation contains estimates and other statistical data made by independent parties and by us relating to our clinical data, market size and other data about our industry. This data involves a number of assumptions and limitations, and you are cautioned not to give undue weight to such data and estimates. In addition, projections, assumptions and estimates of our future performance and the future performance of the markets in which we operate are necessarily subject to a high degree of uncertainty and risk.

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Aileron Acquisition of Lung Therapeutics

Transaction Summary

Use of Proceeds

Key Management and Board

• Aileron Therapeutics, Inc. ("Aileron") Nasdaq: ALRN has acquired Lung Therapeutics, Inc. ("Lung Tx")
• Lung Tx has multiple clinical stage candidates targeting orphan pulmonary and fibrosis indications
• Aileron announced a concurrent private placement of approximately $18 million which is expected to close on November 2, 2023
• Securities to be issued in the private placement consist of Series X non-voting convertible preferred stock and warrants to purchase Aileron common stock
• Aileron intends to seek shareholder approval of the conversion of the Series X non-voting preferred stock into common stock
• On a post-conversion basis (excluding any potential exercise of warrants issued in the private placement), shares of common stock outstanding is expected to be approximately 32.2 million, notwithstanding certain beneficial ownership limitations set at, and not to exceed 19.99%
• As of September 30, 2023, on a pro forma basis to give effect to the receipt of gross proceeds of the private placement, the combined company cash and cash equivalents was approximately $29 million.
• Proceeds from the private placement will primarily be used to complete the ongoing Phase 1b clinical study of LTI-03 and for general corporate purposes
• Expected to support runway into fourth quarter of 2024
• Aileron to continue to be led by Aileron Chief Executive Officer, Manuel C. Aivado, M.D., Ph.D and Susan Drexler, M.B.A., C.P.A., Interim Chief Financial Officer, and by Brian Windsor, Ph.D, former CEO of Lung Tx, who has been appointed as President and Chief Operating Officer of Aileron
• Board of Directors will be comprised of four continuing directors from Aileron: Chairman Josef H. Von Rickenbach, Manuel C. Aivado, M.D., Ph.D, Reinhard J. Ambros, Ph.D, and Nolan Sigal, M.D., Ph.D. and two directors from Lung Tx who have been appointed to the Aileron Board: William C. Fairey and Alan A. Musso

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Clinical-stage Biotech with Pulmonary Pipeline

Therapies for Underserved Fibrosis and Pulmonary Conditions

LTI-03	Phase 1b
Idiopathic Pulmonary
Fibrosis
LTI-01	Phase 2b
Loculated Pleural Effusions	ready
LTI-05	PC
Cystic Fibrosis

• Preclinical evidence supporting the ability to protect healthy lung epithelial cells and to reduce pro-fibroticsignaling
• Demonstrated ability to increase sRAGE, a prognostic biomarker of IPF
• Potentially fatal disease with no approved drugs
• Completed Phase 1b and Phase 2 trials; similar mechanism as existing, off label therapeutic use
• ENaC inhibitor intended for the 15-20%of CF pts. who do not respond to
  CFTR modulators
• 100% inhibition and localized activity (safety profile) in preclinical studies

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Members of Advisory Board and Consultants to Company are Leading KOLs in Targeted Indications

Idiopathic Pulmonary Fibrosis

Toby Maher, M.D., Ph.D.		Andreas Gunther, M.D.
Univ. of Southern California; National Lung		Justus-Liebig University, Giessen,
and Heart Institute at Imperial College London		Germany

Fernando J. Martinez, M.D., M.S.		Ganesh Raghu, M.D.
Weill Cornell Medical College		Univ. of Washington Medical Center

Loculated Pleural Effusions

Najib M. Rahman, M.D.

Oxford Centre for Respiratory Medicine,

UK

Jason Akulian, M.D., M.P.H.

UNC School of Medicine

Fabien Maldonado, M.D.

Vanderbilt University Medical Center

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Multiple Orphan Disease Programs with Upcoming Milestones

Preclinical

Phase 1

Phase 2

Phase 3

Upcoming Milestones

LTI-03

Idiopathic Pulmonary Fibrosis

LTI-01

Phase 1b topline data Q2 2024

Loculated Pleural Effusion Malignant Pleural Effusion

Ready for Phase 2b initiation

LTI-05

Cystic Fibrosis

Other Programs

Multiple fibrotic indications

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LTI-03: A Novel Treatment for

Idiopathic Pulmonary Fibrosis

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LTI-03 is a Peptide Region of Caveolin-1 Protein Indicated for Idiopathic Pulmonary Fibrosis

• Multiple preclinical studies support dual mechanism of Cav1 - ability to inhibit multiple pro-fibrotic pathways and protect lung epithelial cells
• We believe current SOC treatment options offer modest clinical benefit, have significant side effects and intolerance, and are not curative
  o ~100,0001 IPF patients in the U.S. with expected median survival 2-5 years2 from diagnosis
• Successfully completed Phase 1a randomized, double-blindplacebo-controlled study in healthy normal volunteers
  o Currently in a Phase 1b randomized, double-blindplacebo-controlled study
• sRAGE - prognostic biomarker of IPF disease preferentially increased in ex-vivo IPF tissue samples and Phase 1a treated patients
  o RAGE is primarily expressed by epithelial cells in lung tissue

1 United States National Library of Medicine website.

2 Nathan et al. Long-term Course and Prognosis of Idiopathic Pulmonary Fibrosis in the New Millennium. Chest Journal Volume 140, ISSUE 1, P221-229, July 2011

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Caveolin-1: a Key Regulator in Fibrosis

Fibroblasts, epithelial cells, endothelial cells,

myocytes, adipocytes, & immune cells.

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Caveolin-1 Modulates Multiple Fibrosis-Related Pathways

Adapted from Gvaramia et al, Matrix Biology, 2013

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