Aileron Therapeutics Announces Presentation of New Preclinical Data at Upcoming AACR-NCI-EORTC International Conference on Molecular Targets and Cancer Therapeutics 2021

BOSTON, Sept. 30, 2021 (GLOBE NEWSWIRE) — Aileron Therapeutics (Nasdaq: ALRN), a chemoprotection oncology company focused on fundamentally transforming the experience of chemotherapy for cancer patients, today announced it will present new preclinical data at the upcoming AACR-NCI-EORTC International Conference on Molecular Targets and Cancer Therapeutics demonstrating a potential secondary application of its novel, selective chemoprotective agent ALRN-6924 to also protect against radiation-induced toxicities.

Aileron is currently developing ALRN-6924, a first-in-class MDM2/MDMX dual inhibitor, to selectively protect healthy cells in patients with cancers that harbor p53 mutations to reduce or eliminate chemotherapy-induced side effects while preserving chemotherapy’s attack on cancer cells. ALRN-6924 is designed to activate p53 in normal cells, which in turn upregulates p21, which pauses cell cycle in normal cells but not in p53-mutated cancer cells. A Phase 1b randomized, double-blind, placebo-controlled study is currently underway in the United States and Europe evaluating ALRN-6924 in patients with advanced p53-mutated non-small cell lung cancer undergoing treatment with first-line carboplatin plus pemetrexed with or without immunotherapy. Aileron is pursuing a clinical development strategy designed to advance its vision to bring selective chemoprotection to all patients with

p53-mutated cancer regardless of type of cancer or chemotherapy.

In the AACR-NCI-EORTC poster presentation, Aileron will share data showing ALRN-6924’s activity as a radioprotective agent in preclinical models of acute radiation toxicity, leveraging the same mechanism of action that enables ALRN-6924 to protect against chemotherapy-induced toxicities. The poster details are as follows:

Poster Title:

The Investigational Chemoprotection Drug ALRN-6924, a Dual Inhibitor of MDMX and MDM2, Shows Potential for Radioprotection

Poster #:

P211

Date/Time:

All poster presentations will be made available by the conference at the opening of the meeting on October 7, 2021 at 9:00 a.m. ET.

About Aileron Therapeutics

Aileron is a clinical stage chemoprotection oncology company focused on fundamentally transforming the experience of chemotherapy for cancer patients. ALRN-6924, our first-in-class MDM2/MDMX dual inhibitor, is designed to activate p53, which in turn upregulates p21, a known inhibitor of the cell replication cycle. ALRN-6924 is the only reported chemoprotective agent in clinical development to employ a biomarker strategy, in which we exclusively focus on treating patients with p53-mutated cancers. Our targeted strategy is designed to selectively protect multiple healthy cell types throughout the body from chemotherapy while ensuring we do not protect cancer cells. As a result, healthy cells are spared from chemotherapeutic destruction while chemotherapy continues to kill cancer cells. By reducing or eliminating multiple chemotherapy-induced side effects, ALRN-6924 may improve patients’ quality of life and help them better tolerate chemotherapy. Enhanced tolerability may result in fewer dose reductions or delays of chemotherapy and the potential for improved efficacy.

Nearly 1 million patients in the U.S., across all cancer types, are diagnosed annually with p53-mutated cancer. Our vision is to bring selective chemoprotection to patients with p53-mutated cancers regardless of type of cancer or chemotherapy. Visit us at

aileronrx.com

to learn more.

Forward-Looking Statements

Statements in this press release about Aileron’s future expectations, plans and prospects, as well as any other statements regarding matters that are not historical facts, may constitute forward-looking statements within the meaning of The Private Securities Litigation Reform Act of 1995. These statements include, but are not limited to, statements about the potential of ALRN-6924 as a chemoprotective agent or a radioprotective agent and Company’s strategy and clinical development plans. The words “anticipate,” “believe,” “continue,” “could,” “estimate,” “expect,” “intend,” “may,” “plan,” “potential,” “predict,” “project,” “should,” “target,” “would” and similar expressions are intended to 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 whether Aileron’s cash resources will be sufficient to fund its continuing operations for the periods anticipated or with respect to the matters anticipated; whether initial findings or results of clinical trials will be indicative of final results of those trials or results obtained in future clinical trials, including trials in different indications or with different chemotherapies; whether ALRN-6924 will advance through the clinical trial process on a timely basis, or at all; whether the results of such trials will be accepted by and warrant submission for approval from the United States Food and Drug Administration or equivalent foreign regulatory agencies; whether ALRN-6924 will receive approval from regulatory agencies on a timely basis or at all; whether, if ALRN-6924 obtains approval, it will be successfully distributed and marketed; uncertainties as to the impact the coronavirus pandemic may have on the timing of our clinical development, clinical supply and our operations; and other factors discussed in the “Risk Factors” section of Aileron’s annual report on Form 10-Q for the quarter ended June 30, 2021, filed on August 11, 2021, and risks described in other filings that Aileron may make with the Securities and Exchange Commission. Any forward-looking statements contained in this press release speak only as of the date hereof, and Aileron specifically disclaims any obligation to update any forward-looking statement, whether because of new information, future events or otherwise.