Aileron Therapeutics, Inc., a clinical stage biopharmaceutical company that is developing first-in-class therapeutics based on its proprietary Stapled Peptide drug platform, announced today that it has secured $30 million in Series E equity financing with full participation by all existing investors including Apple Tree Partners, Roche Venture Fund, Novartis Venture Funds, Lilly Ventures, SR One and Excel Venture Management. Proceeds from the financing will be used to advance Aileron's pipeline of clinical candidates as well as advance further platform development. In particular, the financing will accelerate Aileron's proprietary oncology clinical candidate, ALRN-6924, into clinical development in 2014 as a highly potent and specific re-activator of p53, a tumor suppressor protein that represents one of the most important oncology drug targets. In addition, Aileron will continue to advance ALRN-5281, its novel long-acting growth-hormone-releasing factor (GRF) agonist currently in phase 1 clinical development for orphan endocrine disorders. In conjunction with the financing, Scott Kapnick, CEO of Highbridge Capital Management, LLC, will become Chairman of the Board.

'These funds will enable Aileron to build on the first successful clinical trial of a stapled peptide this year and expand its clinical pipeline of first-in-class therapeutics. We now have the opportunity to advance ALRN-6924 into the clinic as the first full re-activator of wild-type p53, and our therapeutic approach has the potential to address up to 50% of all cancers including breast cancer, leukemia, liposarcoma, melanoma and colon cancer. We will also continue trials of ALRN-5281, a novel GRF for orphan endocrine disorders including adult growth hormone deficiency and other age-related diseases where growth hormone replacement therapy has substantial liabilities,' said Joseph A. Yanchik III, president and chief executive officer of Aileron Therapeutics. 'Aileron is distinguished as a biotechnology company in our unique ability to translate this novel Stapled Peptide science into drug candidates, and we are honored to have a dedicated syndicate of investors, including four of the top global pharmaceutical companies, who continue to provide very substantial support for our efforts.'

'Aileron's founders, management team and investors have done an outstanding job of creating a leading company in the rapidly emerging field of Stapled Peptide drug development and research,' said Mr. Kapnick. 'Aileron's lead programs, as well as its research and development capabilities in the area of stabilized peptide drugs, promise to create substantial value for both patients and investors.'

The financing follows on recent progress by Aileron in its p53 program where preclinical efficacy data showed that its Stapled Peptide precursor to clinical candidate ALRN-6924 restored p53 activity through direct inhibition of both MDM2 and MDMX, the two key endogenous suppressors of p53, as published in Proceedings of the National Academy of Sciences (PNAS).

About P53 and ALRN-6924

P53, known as 'the guardian of the genome' because it repairs damaged DNA or triggers cell death in pre-cancerous cells, is one of the most important known tumor suppressor proteins, as it is shown to be inactivated in virtually all human cancers. As half of all cancers circumvents p53's protective mechanisms by the over-expression of the inhibitory proteins MDM2 and MDMX, Aileron's stapled peptide is novel in that it can selectively bind to and inhibit both proteins equally, thereby restoring p53 function. Examples of p53-dependent cancers include breast cancer, leukemia, liposarcoma, melanoma, and colon cancer. ALRN-6924, Aileron's proprietary Stapled Peptide re-activator of the wild type p53 tumor suppressor protein, is planned for entry into Phase 1 clinical testing in 2014 for both liquid and solid tumor patients who test for wild-type p53. Aileron recently acquired the rights to ALRN-6924, which was originally developed in partnership with Roche.

About Stapled Peptides

Stapled Peptides are an emerging class of drugs with a unique set of properties that fully capitalize on 25 years of genetic research to attack the critical drivers of complex diseases, including cancer, endocrine/metabolic disorders and inflammation. Aileron's proprietary Stapled Peptide drug platform locks peptides into their biologically active shape and imparts unprecedented pharmaceutical stability within the body. Stapled Peptide drugs are derived from natural peptides and are designed to potently and specifically target protein-protein interactions both inside and outside the cell. This new class of drugs represents a fundamentally new therapeutic approach to modulate signaling pathways to treat human disease.

About Aileron Therapeutics

Aileron Therapeutics is a clinical stage biopharmaceutical company that is developing first-in-class therapeutics based on its proprietary Stapled Peptide drug platform. With its proprietary Stapled Peptide platform, Aileron aims to dramatically improve the treatment of a wide range of diseases -- including cancer and metabolic and endocrine conditions -- and positively impact the lives of millions of patients. Aileron's lead drug development programs are its p53 re-activator for the treatment of cancer, ALRN-6924, and ALRN-5281, a long-acting, growth hormone releasing factor (GRF) for adult growth hormone deficiency that is currently in Phase 1 clinical trials. For more information, please visit www.aileronrx.com.