aibioParabilis Medicines closes private placement of 4,166,666 shares to Regeneron alongside IPO
Tickers PBLS
Parabilis Medicines (Nasdaq: PBLS) sold shares to Regeneron at 90% of the $20.00 IPO price under a Stock Purchase Agreement dated June 9, 2026. The placement closed June 11, 2026.
Key facts
- Company
- Parabilis Medicines, Inc. (NASDAQ: PBLS)
- News type
- Financings
- Primary source
- Parabilis Medicines, Inc. Form 8-K filed June 11, 2026 (SEC EDGAR)
Parabilis Medicines, Inc. (Nasdaq: PBLS) sold 4,166,666 shares of its voting common stock to Regeneron Pharmaceuticals, Inc. in a private placement that closed on June 11, 2026, alongside its initial public offering. The company disclosed the closing in a Form 8-K signed June 11, 2026, by chief financial officer Thomas Kotarakos. The shares were sold under a stock purchase agreement dated June 9, 2026, filed as Exhibit 10.1.
The price and the size
The agreement sets the placement at $75,000,000. The number of shares is that amount divided by the IPO-based purchase price, rounded down to a whole share. The price is 90% of the initial public offering price, which the agreement says will be the price on the cover of the final prospectus. The 8-K gives the IPO price as $20.00 a share. The share count of 4,166,666 is the result of that formula.
Regeneron therefore bought below the price public IPO buyers paid, and the share count followed from the final IPO price rather than a fixed number.
Who arranged it
The 8-K names no placement agent for the private placement. The agreement says the company alone is responsible for any placement agent's fees, financial advisory fees or broker's commissions, except for anyone engaged by Regeneron. The filing identifies no such person.
The agreement does name the underwriters of the IPO. It recites that the company will enter into an underwriting agreement with Leerink Partners LLC, BofA Securities, Inc., Evercore Group L.L.C. and Guggenheim Securities, LLC, as representatives of the several underwriters. The agreement does not say who holds a lead or sole role among them, and it does not say which law firm acted as counsel to the company or to the underwriters.
The terms for Regeneron
Regeneron represented that it is an institutional accredited investor under Rule 501 of Regulation D, and that it is buying for investment and not for resale. The 8-K says the shares were offered without general solicitation. They were issued under Section 4(a)(2) of the Securities Act and are not registered.
Regeneron gets piggyback registration rights. Those rights are granted under the company's sixth amended and restated investor's rights agreement, dated January 6, 2026, and they carry that agreement's restrictions and waiver provisions. The company must pay the expenses of those registrations, other than selling expenses. That gives Regeneron a route to sell the shares in a later public offering, which the agreement does not time.
The agreement also bars the company from integrating the placement with any other offering in a way that would require the shares to be registered. Regeneron's transfer of the shares is limited by the lock-up it signed in connection with the IPO.
Closing conditions
The closing was set to occur concurrently with the IPO closing. The agreement says it terminates automatically if the underwriting agreement is terminated before any shares are sold to the underwriters, if the IPO registration statement is withdrawn, or if the closing has not occurred by June 25, 2026. Either party may also walk away if a closing condition fails, and that release does not cover fraud or willful breach.
The charter and bylaws
Alongside the placement, the company filed a seventh amended and restated certificate of incorporation in connection with the IPO. It authorizes 800,000,000 common shares, including 600,000,000 voting and 200,000,000 non-voting shares, and 10,000,000 undesignated preferred shares. The certificate removes all references to the company's earlier preferred stock series.
The company also adopted amended and restated bylaws, including an advance notice procedure for stockholder proposals and director nominations.
What the filing does not say
The 8-K and the agreement describe the placement and the IPO structure, but they do not describe the company's business, its clinical programs, its cash balance, its losses or its use of the proceeds. The filing gives no net proceeds figure after fees, and it does not state the number of shares outstanding after the IPO.
The 8-K cites File No. 333-296032 for the Form S-1 covering the IPO.