Business Acquisition	9 Months Ended
Sep. 30, 2024
Business Combination, Asset Acquisition, and Joint Venture Formation [Abstract]
Business Acquisition	3. Business Acquisition On October 31, 2023, Aileron acquired 100% of Lung, pursuant to the Lung Acquisition Agreement. At the closing of the Lung Acquisition, Aileron issued to the stockholders of Lung 344,345 shares of its common stock (excluding 221 fractional shares from the total 344,566 shares pursuant to the Lung Acquisition Agreement) and 19,903 shares of its newly designated Series X non-voting convertible preferred stock (the “Series X Preferred Stock”) (excluding 238 fractional shares from the total 20,141 shares pursuant to the Lung Acquisition Agreement). Each share of Series X Preferred Stock is convertible into 1,000 shares of common stock. The Company paid $290 cash in lieu of fractional shares of both common stock and Series X Preferred Stock. In addition, Aileron assumed all of Lung’s stock options (1,780,459) and all warrants (726,437) exercisable for Lung common stock immediately outstanding prior to the closing of the Lung Acquisition, each subject to adjustment pursuant to the terms of the Lung Acquisition Agreement. Immediately following the closing of the Lung Acquisition, on October 31, 2023, Aileron entered into a Stock and Warrant Purchase Agreement (the “Purchase Agreement”) with a group of accredited investors, pursuant to which Aileron issued and sold (i) an aggregate of 4,707 shares of Series X Preferred Stock, and (ii) warrants (the “PIPE Warrants”) to purchase up to an aggregate of 2,353,500 shares of Aileron common stock (the “PIPE Warrant Shares”), for an aggregate purchase price of approximately $18,429, which included the conversion of certain convertible promissory notes in the aggregate principal amount of $1,553 issued by Lung to Bios Partners, the majority stockholder of Lung prior to the closing of the Lung Acquisition, at a 10% discount to the per share price of the Series X Preferred Stock (collectively, the “PIPE Financing”). The PIPE Financing closed on November 2, 2023. Each share of Series X Preferred Stock is convertible into 1,000 shares of common stock. At the 2023 annual meeting of stockholders (the “2023 Annual Meeting”), the Company’s stockholders approved the issuance, in accordance with Nasdaq Listing Rule 5635(a), of shares of common stock, upon conversion of the Company’s outstanding Series X Preferred Stock. On March 5, 2024, subject to then existing beneficial ownership limitations, 11,957 shares of Series X Preferred Stock were automatically converted into 11,957,000 shares of common stock. The Lung Acquisition was accounted for under the acquisition method of accounting under ASC 805, Business Combinations. Under the acquisition method, the total purchase price of the acquisition is allocated to the net tangible and identifiable intangible assets acquired and liabilities assumed based on the fair values as of the date of the acquisition. Consideration transferred is the sum of the acquisition-date fair values of the assets transferred, the liabilities incurred by the acquirer to the former owners of the acquiree, and the equity interests issued by the acquirer to the former owners of the acquiree (except for the measurement of share-based payment awards). The Company recorded the assets acquired and liabilities assumed as of the date of the Lung Acquisition based on the information available at that date.

Business Acquisition

9 Months Ended

Sep. 30, 2024

Business Combination, Asset Acquisition, and Joint Venture Formation [Abstract]

3. Business Acquisition

On October 31, 2023, Aileron acquired 100% of Lung, pursuant to the Lung Acquisition Agreement. At the closing of the Lung Acquisition, Aileron issued to the stockholders of Lung 344,345 shares of its common stock (excluding 221 fractional shares from the total 344,566 shares pursuant to the Lung Acquisition Agreement) and 19,903 shares of its newly designated Series X non-voting convertible preferred stock (the “Series X Preferred Stock”) (excluding 238 fractional shares from the total 20,141 shares pursuant to the Lung Acquisition Agreement). Each share of Series X Preferred Stock is convertible into 1,000 shares of common stock. The Company paid $290 cash in lieu of fractional shares of both common stock and Series X Preferred Stock. In addition, Aileron assumed all of Lung’s stock options (1,780,459) and all warrants (726,437) exercisable for Lung common stock immediately outstanding prior to the closing of the Lung Acquisition, each subject to adjustment pursuant to the terms of the Lung Acquisition Agreement.

Immediately following the closing of the Lung Acquisition, on October 31, 2023, Aileron entered into a Stock and Warrant Purchase Agreement (the “Purchase Agreement”) with a group of accredited investors, pursuant to which Aileron issued and sold (i) an aggregate of 4,707 shares of Series X Preferred Stock, and (ii) warrants (the “PIPE Warrants”) to purchase up to an aggregate of 2,353,500 shares of Aileron common stock (the “PIPE Warrant Shares”), for an aggregate purchase price of approximately $18,429, which included the conversion of certain convertible promissory notes in the aggregate principal amount of $1,553 issued by Lung to Bios Partners, the majority stockholder of Lung prior to the closing of the Lung Acquisition, at a 10% discount to the per share price of the Series X Preferred Stock (collectively, the “PIPE Financing”). The PIPE Financing closed on November 2, 2023. Each share of Series X Preferred Stock is convertible into 1,000 shares of common stock.

At the 2023 annual meeting of stockholders (the “2023 Annual Meeting”), the Company’s stockholders approved the issuance, in accordance with Nasdaq Listing Rule 5635(a), of shares of common stock, upon conversion of the Company’s outstanding Series X Preferred Stock. On March 5, 2024, subject to then existing beneficial ownership limitations, 11,957 shares of Series X Preferred Stock were automatically converted into 11,957,000 shares of common stock.

The Lung Acquisition was accounted for under the acquisition method of accounting under ASC 805, Business Combinations. Under the acquisition method, the total purchase price of the acquisition is allocated to the net tangible and identifiable intangible assets acquired and liabilities assumed based on the fair values as of the date of the acquisition. Consideration transferred is the sum of the acquisition-date fair values of the assets transferred, the liabilities incurred by the acquirer to the former owners of the acquiree, and the equity interests issued by the acquirer to the former owners of the acquiree (except for the measurement of share-based payment awards). The Company recorded the assets acquired and liabilities assumed as of the date of the Lung Acquisition based on the information available at that date.