Rapport Therapeutics Stock Falls 18% as It Launches Stock and Convertible Notes Offerings

Rapport Therapeutics, Inc. (Nasdaq: RAPP) fell 18.3% on Wednesday, Oct. 28, 2026, closing at $22.50 from a previous close of $27.54, on volume about 18.5 times normal. The S&P 500 ETF (SPY) rose 0.34% over the same session.

The move came a day after the company filed two prospectus supplements on Oct. 27. In a 424B5 filed at 4:52 p.m. ET, Rapport proposed a public offering of common stock, with the price left blank in the preliminary document. A second 424B5, filed at 4:55 p.m. ET, covers a concurrent offering of convertible senior notes due 2032.

Concurrent offerings

The filings show the two offerings are linked but not contingent on each other. Morgan Stanley, Leerink Partners and Evercore ISI are named on the notes, and Morgan Stanley, Leerink Partners and Evercore Group are also placement agents for a concurrent private placement tied to the stock offering. The stock offering's underwriters are Morgan Stanley, Leerink Partners, Evercore ISI, BTIG and Citizens Capital Markets. The preliminary documents leave the offering size, price and note coupon blank. The stock offering listed a last reported sale price of $25.33 on Oct. 26, which is above Wednesday's close.

Cash and losses

Rapport reported cash and equivalents of $63.6 million and short-term investments of $372.5 million as of June 30, 2026, $436.1 million in all. For the quarter ended that date, the company reported an operating loss of $60.8 million, wider than the $29.5 million loss a year earlier. Net loss for the quarter was $56.6 million, compared with $26.7 million a year earlier. For fiscal 2025, the company reported a net loss of $111.5 million.